Regarding Dewalts...
The BMS only controls the LVC and OCP during discharge. If we bypass the BMS we run into the problem of longevity. Bypassing the BMS and using the Cycle Analyst gives US control over the DOD and current output and hurts longevity if we increase DOD and over current. But, I'm not sure we want control over them? Homostupidous? The built in Dewalt BMS protects the pack from us. We can only increase the amount of packs we use to a 2s setup? Not much better. Like this?
At 36V/2.4Ah each, this setup would be 72V/4.8Ah? And if 2s is the most they can handle and I need 36V, 2s2p is the best I can do with unaltered Dewalts?
How much voltage the BMS can take is dependent on what FETs are used to provide LVC. The higher voltage the FETs are rated for, the higher voltage system can be used.
This and 2s max may be why several people are taking apart Dewalts for the cells. They are eliminating the 15A fuse too.
No, that's a disaster. Eliminate all the grey wires and then you have a 4s string.
Damn it. I keep doing that. Sorry, I was tired :(
You got the parallel right, though.
I finally did something right :)
Easiest way to keep the packs from trying to supply more than 15A is to use enough so that the controller ends up limiting the C-rate to 7 or less (e.g. you'd need about 60Ah worth of packs on your 400A controller).
LOL 60Ah with Dewalts? How? 25 packs in series? 2.4Ah x 25 = 60Ah. That would be sweet, a 36V/60Ah Dewalt A123 25s1p pack :)
Regarding LiFePO4 PHEV and BEV...
Okay in lameman terms, dont we need the BMS to limit usage of the batteries to only the middle 50% to get 100,000 miles out of the batteries. So to get the longevity necessary and to make it useful in a PHEV or BEV can we simply increase the size of the bank and the Ah of the LiFePO4 pack?
30kWh is what the average car would need for 100-150mi range).
30,000Wh? HOW?
Why medium sized? You planning on having lots of kids soon? What Year? Make? Model? Give me your 1st and 2nd choice.
Have you seen the new Ka-dill-e-ak Escalade hybrid? A whopping 12 MPG in the city! Whoohoo! The rich are trying to be environmentally conscience at least. *cough* No wonder GM is bankrupt!
Regarding Pinglikes...
Is combining different voltages okay? Like combining a 24V pack with a 36V pack in series, totalling 60V. Or is this another disaster?
Combining different AH levels may/will hurt the lower Ah pack?
Regarding Kelly controllers...
My present controller is 24V-36V/400A. I can theoretically run 100s of Ah's through it, right? Can I theoretically run a 1000A to it without hurting it? Will it simply cut out or only allow 400A max or will it be a little melted hunk of metal fused to the road. If I hook up a 48V pack to my controller, will the controller OVP kick in and shut down, or will it only allow 36V to flow somehow?
LiFe is just getting started.
Your life is :)
If they can make more money on something else, they will kill LiFers.
Prices HAVE been slowly coming down as more competition comes on the market.
Seems like it. I found 48V/20Ah pinglike Lifers for $88. Dont ask me how many you have to buy though :)
LiCo too dangerous? LOL You are assuming that big business and our government cares. Ever heard of a Corvair, Pinto, gas tanks on the outside of the frame rails on Chebby trucks, firestone, single hull Exxon Valdez, DCB, alcohol, cigarettes, prescription medicines, over-the-counter medicines, DDT, insecticides, red dye #5, flouride, preservatives, global warming, tap water, HMOs, war, etc. etc. etc.....
Yes, the chance of something going wrong is slim,
Thats why they do an Actuarial Analysis... Share holder profits versus Lawsuit judgments and settlements...
There will just be a melted hunk of metal fused to the road.
LiCo Police BEV half way into a hot pursuit car chase. :)
$10/gal would be peanuts overall.
Life will be like Mad Max when that happens. WWIII is almost here. Why do you think we are in Iraq? 911? Nope, that was the excuse they needed. At least their will be lots of LiFers to power the guidance systems on the nukes. When its over we will have access to cheap LiFers, but they may have a little dried blood on them.
you can already build a BEV with 300mi+ range if you've got the money.
Not me yet, but thats that the plan someday. Right after my pyramid :)
I still think I don't have near enough power to win.
Good! I want to win the drag race. You win the 50 mile marathon... for now :)
I think I've seen 3s before, for 99V nominal. "Think" being the key operative word. You can put as many in parallel as you want.
That's a 2s4p. 66V 9.6Ah.
Second try's the charm. :)
1s25p. :P
You're fine without the BMS for this reason: The cells are capable of 30C continuous, meaning that they can be discharged completely in 2 minutes. Nobody but drag-racers are going to get any use out of C rates that high. I'm guessing you're going to want runtimes of more than 2 minutes, so even a relatively small 20Ah (600A continuous) pack would be more than able to handle your controller.
Yeah. That's kind of why I expect even my duct-tape pack to last a really long time; I'll only very rarely use more than 10Ah of it. Typically only around 5Ah.
Of course, the tradeoff is that doubling the pack size for really long life also doubles the cost. Plus (and more importantly) you may not even be able to fit a pack that big into whatever you happen to be building.
However, given that current-generation LiFe should have approximately 5x the cycle life of NiMH, our primary concern would be the calendar life of the batteries, since it'd take a loooooong time to drive 500,000 miles.
30kWh is the estimate I hear based off of the 300Wh/mi guess that seems to be so popular for conversions. IMO, that's more accurate for a heavier car or hilly environments. A good, light, aerodynamic car could get down to 100Wh/mi or less. I forget what I translated the Aptera's 300mpg figure into. Think it was like 36Wh/mi, which is extremely impressive for a car; some faster ebikes have equal or even lesser efficiency figures.
Medium because I'm considering something the size of a Smart Car to be small. I want some leg room and a place to stuff my bike. :)
No idea on what sort of car. I know almost nothing about them (unless it comes to repair, where I know at least how to keep it running), except that Ferraris, Porsches, Corvettes, and Bugattis are fast. :/
But it prolly won't be a 90's car. I don't know why, but I've noticed that if I'm looking around on the road, I can identify almost all the 90's cars because I find them ugly and boxy.
The pinglikes need either a BMS upgrade or some diodes to protect them if they're being put in series. Otherwise it's okay.
Interestingly, because of the way the BMS/diode thing works, two different Ah packs can be used in series. When one cuts out, the diode starts passing the power from only the second pack until that one runs out of power and cuts out.
Technical time:
Controllers use something called PWM (pulse-width modulation) to vary the power they output. All PWM is is the modulation of a DC-biased square wave power signal. The lower the duty cycle, the less time the power is on. This is often compared to flipping a switch and leaving it on a certain percentage of the time about 18,000 times per second.
The motor effectively sees a varying voltage across its terminals depending on the duty cycle. Because of a combination of BEMF and Ohm's law, this causes it to draw less or more amps.
There is also a shunt inside the controller. A shunt is basically a big, low-value (say, 0.001 Ohms) resistor. Power passes through this resistor on its way to the motor. This produces a voltage potential across its ends, which the controller monitors. If the voltage gets too high because there's too many amps flowing through it, the controller scales back the duty cycle of the PWM. Because this lowers the apparent voltage to the motor, it also lowers the amps. The limiting happens almost instantly (we're talking millisecond-long delays or less), so any overcurrent doesn't last nearly long enough to damage anything.
Basically, the batteries won't have more than 400A drawn from them because the controller doesn't let it happen.
As for 48V, it depends. If the controller doesn't have an overvoltage protection built in (I think most golf cart controllers do), then it just wont run. If it doesn't, then it will depend on the components used. If they can handle the increased voltage, then 48V can be safely used. Because the amp limit is independent of voltage, you still will have the same 400A limit.
And my oh-so-accurate actuarial analysis is that the bad PR generated from any accidents would offset anything else a car maker using LiPo/Co could do by an irreparable degree. I mean, look at the laptop fires: There were hardly any of them but the general populous is STILL wary of any battery with "Li" in its chemistry. Manufacturers would do well to point out the differences between battery chemistries. The advantages of LiFe (intrinsic safety; long life) make good selling points.
Heh. I know that's not really a LiCo powered BEV because there's too much of it left. :D
Hmm...Marathon, FTW. ;)
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Marketing math makes it 33V + 33V = 72V.
Oh!! 2.4Ah x 4p = 9.6Ah Duh! Damn!
Would you believe me if I said I was referring to only the middle 4.8Ah 50%Ah SOC that we actually get to use? :)
I think I finally got it...
Xs (positives connecting to negatives)
+
Xp (positives connecting to positives)
=
total amount of batteries
Okay, Link 312, JY 88. Im catching up fast. You may ask yourself how you dropped to 312 and I got up to 88 so fast? I used a ^1.3 peukert effect on your score and marketing math on mine :)
OMG!!!
Okay, Homostupidous (me) Technical time...
C x Ah = A
30C x 9.6Ah = 288A Hmmm, so if I draw 288A on a 2s4p pack of 33Vn/2.4Ah A123 Dewalts they will only last 2 minutes? You're kidding right?
T = C / I^n
.033h = 30C / 288A^1.01 . . . . . .033 = 2 minutes = 1/30 hour, 1.01 = A123 Peukert exponent
.033h = 30C / 304.78
.033 = .098 ???
I^n x T = C
288A^1.01 x 0.033h = C
304.78 x 0.033h = C
10.06 = C ???
How about ~6 minutes at 30C Teach?
I^n x T = C
288A^1.01 x 0.1h = C . . . . .1h = 6 minutes
304.78 x 0.1h = C
30.48 = C ???
JY 127???
Twice the bang for twice the buck. Makes sense. We want to use just enough batteries to meet our distance and MPH goals without hurting the cycle life of the batteries. Spending twice as much to get twice as many batteries is better than having a small pack of junk batteries in a short period of time because we wore them out and have to buy another small pack.
On a 60 pound bicycle I agree, but on a Etank, or in a Ecar there is lots of room. That must be why the hot set up is to tow a little battery trailer behind their bicycles?
http://www.youtube.com/watch?v=ooTwoJeEVxE&feature=related
Ecars...
Calender life? LOL the LiFers will die of old age before they wont hold a charge. So we cruise around for 100 miles at time at an average 5Ah, using the middle 50%, for 5 years doing everything we are supposed to do to protect the batteries and then they suddenly die of a heart attack? LOL
Wow! And still cruise at 55MPH on flat land?
That is amazing! I gotta check it out!
I would want a pre 70s (Cobra kit car, Sunbeam, MG, Fiat, or Triumph convertible, Austin Mini Cooper, 914, bug, or Honda 600) or 2000+ (BMW Z3, Metro, Mini, or Fit) small car and no damn bicycle. Bad knees. Buy a clamp on bike rack. IIRC, some genuius said it takes 10 times as much power to go twice as fast because of aerodynamic drag. Small car = less weight and lower aerodynamic drag.
On to the Pinglikes...
Upgrading the BMS is not an option for me.
Assuming I drew this damn 2s4p correctly :) Where do the diodes go on this set up
Great! Because of the way the BMS/diode thing work I can use unmatched Ah batteries if necessary with just the BMS and diodes that come with the Pinglikes?
Your Technical time:
It sounds like you are saying...
1. The controller uses PWM to adjust the volts going to the motor, causing the motor to draw less or more amps. The controller monitors the resistor volts to determine the speed and duration it sets the PWM at???
2. The controller doesnt care what volts come into it as long as the volts are within the range of its LVC and OVP???
3. If I put 48V into a 36V controller w/o OVP the controller will run but it may hurt the controller??? I looked at the Curtis manual and it makes no mention of OVP. Just the LVC. Interestingly, the manual says, "Optional Precharge Resistor" on the contactor.
4. If I put 48V into a 36V controller with OVP the controller wont run???
5. I can run a 24V battery in series through a 36V battery to get 60V???
6. I can run a 24V an 36V together in parallel to get who knows how many volts??? LOL 30V???
Is oh-so-wrong, unfortunately. Facts mean nothing in corporate marketing and governmental disinformation. A few LiFePO4 cars mysteriously kill 20 people right before Exxon announces it has discovered a new, revolutionary, intrinsically safe, and long lasting LiFeBloS2 technology. Coincidence?
The general populous are sheep... Homostupidous!
But, I love your pollyanna belief system Link. Hold on to your innocense as long as you can.
Man, they are giving away 2005 Prius batteries for $400 on ebay, 50 miles from my house. How can I pass them up at this price? I have to go back and look at everything you said about them.
Hey, what do you think about a universal motorcycle conversion kit that converts virtually any ICE chain driven motorcycle to electric? Linkjy's first EV kit?
No, I wouldn't. :P
Well, what if I use some twisted version of inductive current warping to boost my score to 312 x (sqrt)88 = ~2,900?
Far too lazy to check work. I don't even bother to factor in that "exponent" for lithium. IRL, choice of wiring gauge and efficiency of the motor at different amp draws accounts for far more that the batteries' internal resistance.
Actually, by doubling pack size and thereby halving typical DOD, you get a lot more than double the cycle life. (Think it's around triple, but I've never seen anything official.)
Yeah, the trailer thing is popular for those who want long range with cheap batts. I've seen a few with generators on them, too.
Yup. Batteries degrade slowly over time even if you don't use them. Not actually sure of the calendar life on LiFe, but A123 claims 15 years on their cells.
I'm gonna steal this from Fechter for a minute:
You can use mismatched batteries, but I don't see why you'd want/need to...
1. Yah. 'Cept the frequency of the PWM is constant. Irritatingly, it's around 18kHz, which I can still hear.
Useful piccy:
2. Pretty much. I'd imagine there's a slightly reduced cycle life with higher voltage, but I don't think anyone's managed to ride enough to figure out if that's true or how much of a difference it makes. ;)
3. Most cheap scooter controller's don't have OVP. However, the ones that do just won't run. Not sure of how it's usually implemented, but it'll still blow if you go too high.
4. Yah.
5. Yah again.
6. Neva eva put different-voltage packs in parallel. The higher one will try to drain into the lower one, definitely destroying the lower one and possibly the higher one.
Hmm...Don't think it could work that way. It's the initial stages that are sketchy. If they tried to pull something like that right before a new chemistry was introduced, it would be dismissed as a fluke. People are convinced NiMH and NiCD are safe, though they can vent pretty violently if provoked.
And you can bet the "intrinsically safe/long lasting" points are going to be very exaggerated by manufacturers. Would seem kind of odd if they just suddenly announced they were wrong. Odd enough so that they might lose business in favor of someone else's chemistry...
I wonder how EEStor's caps go off. Caps normally explode very, VERY violently, despite having relatively tiny amounts of energy in them. It's been theorized that a cap with the energy density of an EESU would go off roughly the same way TNT does. Wonder how they manage to solve THAT problem.
Oh, yeah, I figured out why that guy said you needed a special charger for Prius NiMH. Apparently, their dV (a dip in voltage at the end of their charge cycle) is so subtle that most chargers miss it.
That'd be an awesome kit, but I'm not sure how easy it would be to pull of in a technical sense. The main issue would be the batteries and how to mount them.
The author of this post isn't responsible for any injury, disability or dismemberment, death, financial loss, illness, addiction, hereditary disease, or any other undesirable consequence or general misfortune resulting from use of the "information" contai
Only I get to cheat. You dont need the help.
Link 215, JY 350 Woohoo, Im in the lead! FTW!
Method of scoring used: Reverse twisted inductive current warping. :jawdrop:
I doubt that you are lazy. Except at doing chores around the house? }:)
Thats why I went with 2/0 wire. One problem out of 100 solved. 99 more to go!
Not much we can do about that, short of switching to a better motor. Or controlling the amps.
I am starting to understand the batteries' internal resistance/impedance thingy a little better.
http://visforvoltage.org/forum/batteries-and-chargers/1449
Seems like a battery may need some amount of resistance. Some internal resistance my help prolong the calender life and avoid mioelectrical infarction before their 15 years is up. I guess we want to have access to all of a batteries' available power (0 resistance) and control it externally, hopefully without killing it IRL.
Ah, triple the bang for twice the buck, even better! Two packs sounds better!
Hmm, a generator on the trailer. :? I was reading about serial generator Hybrids. Has me thiking about a BEV with a parallel generator to recharge the batteries and run the motor when necessary (no AC plug around or no time to sit 8 hours for the batteries to charge)... GEV? More on this when I get out of kindergarten, EVwise.
Well since you didnt spank me for my last 2s4p drawing, I will keep using it
Where is the BMS in Fecther's drawing? Does the diode go between the BMS and batt, or after the BMS? I used my superior deductive reasoning (guessed) and put the diode in between...
The only reason I can think of to use mismatched Ah (matched V) batts is because of price. Say I have two 36V/20Ah pinglikes already. Then I steal a 36V/20AH batt during the last 4 seconds of an auction. "Because of the way the BMS/diode thing works, two different Ah packs can be used in series."
In this case, I would have 108V/20Ah??? 15Ah??? 13.3Ah??? or 10Ah???
Also, I can hook up a 36V/20AH batt and a pair of 36V/10Ah batts in parallel giving me 36V/40Ah without any additional diodes, right???
You cant smell much (SBDs), but at least you can still hear good. My hearing, sight, smell, taste, and a few other things I used to have are shot. Mi mined stiwl wurks gud ;)
1. Oh, I was thinking that the duty cycle was cyclical somehow. Its kinda Cyclothymic. Linear over a time scale, like a interval wave.
3. Okay, do not overvolt the controller.
5. Does it matter whether the 36V or 24V batt in series is closest to the controller?
6. Thats interesting, Different Vs can be in series but neva eva in parallel. Okay, that will save a big headache.
7. Interesting debate starting over mixing (charging and discharging) SLAs and Pinglikes in parallel with different Ah without diodes. I want to do the same thing basically. Keep my SLAs and add a pack or two of Pinglikes.
Cant wait to read your reply over on that thread
http://visforvoltage.org/forum/4554-paralleling-23-48v-20ah-pingping-batteries
Dear Polly, (my moms name BTW)
People are easily convinced to believe whatever they want them to believe.
They will blame it on the dead guy. Or on a patsy, right after the patsy mysteriously commits suicide or has a freak accident LOL
They will just blame it on the democrats and give the company CEO $700,000,000,000. 8)
Geez! What do caps do? Split the atom? Does the extra E stand for Einstein? :) They will just include an on-board fire extinguisher with the cap cars and increase the auto insurance rates for cap cars and blame it on those axis of evil LiFeBlos2 batteries. Or, blame it on the dead guy or the democrats? ;)
Hmmm, so the charger keeps trying to pump more and more charge into the NIMH? This can cause the thermal runaway? Perhaps that is also why the Prius keeps the max charge at 80%? Longevity and fire prevention?
Now that we are on NIMHs...
Since charging in parallel is a problem, can they just be unparalled for charging? Also, since the cell that charges first hogs all the current to the point of exploding, we cant charge them in series either? Then how do they (Toyota) charge them. With 240 Schottky diodes?(whatever that means) And, they have to be wrapped tightly in steel, or something strong, so they are under compression, otherwise the may expand and vent gas through the sidewalls??
This is probably old news to you, but I just read about all the LiFePO4 lawsuits for the first time.
A123's LiFePO'4 Dewalt packs may not be around much longer...
Goodenough, UoTexas Regents and Hydro-Quebec sued A123 (MIT spin-off) in '06 for "spiking" the cathode.
Hydro-Quebec is also suing Valence in Canada. Valence is suing Phostech. Hmmmm, is Valence suing Phostech for alledgedly stealing the technology that UoT is allegedly accusing Valence of stealing? LOL
Its amazing how many of these companies are in bed together via licensing agreements.
A123's LiFePO's are supposedly made by China-BAK. I wonder if Mr. Ping has any relatives at BAK? Cousin Li Bak Po the 4th? :)
Damn, why didnt you patent Phosphate cathodes in 1998? We could have sued everybody!!!
Dont tell me that you were only 7. Thats no excuse LOL
Have you seen these?
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=280271582136
Emotorcycle conversion kits...
Proprietary info below (My lawyer made me say this :)
Okay, figure on a kit for a chain driven 500lb street legal setup (750CC and up). <100 lbs additional for the optional LiFePO4 batt pack. The weight of the single motor is offset with the weight of the ICE removal. We need 20 to 30HP peak from a motor that will last forever. Make it powerful enough for larger bikes to cruise at 55MPH, and it will make smaller bikes fly. One size fits all. The 500 pounder will need to be able to travel 100 miles on a full charge with 150lb rider and 150lb passenger. The charger comes with 20' retractable cord that goes where there bike goes, so they can plug it in whereever they are that has AC.
The batteries could be in a strong self-contained carbon fiber module (you build the batt box), so they can be easily painted to match their bike and mounted in the engine compartment with a few brackets. The motor mounts on the swingarm. Toss in a good controller, a Magura, a contactor activated with a key switch, a few brackets, 20' of 2/0 stranded black cable and connectors, roll of small gauge black wire, 5' of chain, bag of assorted bolts, nuts, washers, and connectors, deadman fuse, dc to dc convertor so they can use the existing lights on their bike. A little noise maker that goes, "Potato, potato, potato!" for Harley conversions. And one that goes, "Wurrrrrr, wurrrrr, wurrrr" for Asian 4 stroke bikes. And one that goes, "Wing!.. Ding! Ding! Ding!" for 2 strokers. :) Keep the gas tank so the bike looks cool.
Everything for under $2000 cost, $3000+ retail plus shipping plus batteries.
Customer demographics... 30 million used motorcycles on the road today.
Start up cost.... $2000 to $200,000
Your thoughts?
Motor type?
100 mile battery pack size V/Ah?
Controller?
Eww chores...'Cept laundry. Laundry's okay.
"Myoelectrical infarction"? What does muscle activity or necrotic tissue have to do with anything?
Also, I've also wondered what would happen to a battery with 0 internal resistance shorted through a 0 resistance load. Best I can come up with is some sort of super-powerful EMP that does who-knows-what to anything close by and destroys every IC in the state.
Uh...neither. Sorta. The BMS itself is only on the - side of the battery. It has taps on all of the cells. The + lead is just a wire. One end of the diode diode goes on the + lead of the battery.
Here's a pic of the thing. The other end of the diode (- end) would go on the fat wire closest to the LVC FETs (square black things). Next to "P-"
Three 36V/20Ah packs in series gives you 108V/20Ah.
Same voltage packs of any size can be put in parallel. Not sure how the BMS likes this, though. Diodes to keep the packs from trying to charge each other would be a good idea, but it would cost you some power in the way of voltage drop. Better to just have the cells themselves in parallel with LiFe, as opposed to whole packs.
No. The controller will see the total voltage of the packs regardless of which is closer.
Yah. I was gonna take a vid of overcharging a small 2.5V 1F supercap and see what kind of a bang it made, but I can't find that damn cap anywhere, and I'm not blowing up my 20F or 50F ones. They cost me too much...
Yeah. That dV is a pain. Makes charging a hassle and you can't charge parallel cells because of it.
Most people who run NiMH/Cd in parallel charge each string with a separate charger.
They can be charged in series because the current through each cell in a string is equal (by the laws of electronics, it has to be). They all receive the same charge. They can sort of self-balance, too, by being fed a very low current after the pack is done charging (like 1/10-1/100C).
I've heard they don't have to be bound up, but I've also seen pics of bloated/melted cells that weren't. I'm inclined to believe the pics.
Heard about the A123 and Valence lawsuits. Not interested enough to pontificate on the consequences. As long as the price of LiFe keeps dropping, I'll be happy. :)
LOL, the only electric vehicle I had seen when I was 7 was some guy in the park riding an electric skateboard.
BMI cells are good quality. Not cheap, but good quality.
Noise makers...nyeh...too much noise on the road already. Plus then we'll have them complaining about the sound quality and the added expense of a sound system. :/
Sub-3k$ 100mi can't be done without some radical modification to the motorcycle's aerodynamics. Batteries just cost too much. Sub-10k$ would be more realistic.
Motor type...give them a pick. Brushed PM for the cheapness, BLDC for the maintenance-free, series for the torque whores, sepex for efficiency, and induction for those who want top-of-the-line (see: $) stuff.
Battery pack V/Ah would depend on the motor. 5kWh should be about right, though.
Controller would also depend on the motor.
Oh, and I'm told the defunct gas tank makes a good place for the controller. ;)
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Laundrys cool! 5 minutes work and 1 hours 25 minutes to do somethin else while they are washing and then drying.
Cell heart attack :)
0 resistance, 0 load? An EMP or a Perpetual Motion machine? :?
So this is more what my drawing should look like?
So this is a BMS? The diode is part of the BMS. Like this?
So what exactly does this diode do?
What are the other things???
Either way, this is something I am not able to do. You can repair these and switch parts out?
Im sorry. That was a typo.
I meant 2 36V/10Ah and 1 36V/20Ah in series.
In this case, I would have 108V/20Ah??? 15Ah??? 13.3Ah??? or 10Ah???
NiMHers...
I may own a Prius Gen III battery pack any minute now. 14 modules. An '05, 29K mile, checked OK 3 weeks ago. If the guy accepts my counter offer to his counter offer to my offer :P
I'm trying to figure out how to use the whole damn pack, metal case and all, on my Etank.
Each module has six 1.2Vn/6.5Ah cells in series, 84 cells
So I'm thinkin' for my 24V-36V controller and in parallel with my 36V SLAs...
5 modules in series
5s x 7.2/6.5Ah = 36V/6.5Ah
2 paralleled sets of 5 modules in series
2p x 36V/6.5Ah = 36V/13Ah. . . 30s2p
with 4 modules (24 cells) left over for spares, but left in the case for proper compression.
Do you have any clue how to do this to Prius batteries?
Dont worry, I will be careful and wear thick rubber gloves and a face shield. I dont mind dying on the Etank, but I wont die building the damn thing :)
You remember that bright idea I had to use 450A fuses? The 3 of them arrived today. I was thinkin' they were bout the size of a roll of quarters... Heres a pic with 12.75" ruler.
OMG! They are 10.5" x 2.5" round and must weigh 5 pounds each. LOL Are you sure 451A DC will blow this monster?
Nice pic! Love Dr E! :sick:
Emotorcycle kit...
Okay, noise makers are out.
$2000 our cost w/o batteries is a maximum.
100 miles per charge is too much? Cant go much lower or the kits wont sell to commuters.
Who you callin' a torque whore, you Sepex Slut?
Okay, 5 choices of motors later, I like that. I like the idea of Regen for start-up. That should help meet 100 mile goal?
Okay, 5kWh battery packs available at additional charge.
Controller choices too? Oy!
You are making production too hard and start-up costs too high. To get started, keep it simple. Think big, but start small. For start-up, I'm thinkin' 1 type of motor, 1 type of controller, and 1 type of battery. Off-the-shelf products as much as possible. The less manufacturing the better and cheaper the costs. I am going to have to buy 1000 units of some of the parts to get a descent price.
A simple, easily completeable, almost plug-N-ride, SAFE, dependable kit for ebike upgraders, ecomotorcyclists, commuters, and hobbyists. Complete instructions included. Some minor drilling, cutting, and crimping required. All they need is a motorcycle, simple tools, and desire to build their own electric motorcycle. And $3000 plus tax :) All shipped in one 80 pound box.
You pick the motor, controller, and batteries???
We can have the batteries drop-shipped.
Where they mount the controller is up to them. They can cut the gasoline tank at their own risk.
And possibly a supermagnet capable of halting the rotation of the Earth's core, thereby removing the planet's natural magnetic shield against cosmic rays and reducing the world to a sun-scorched, Riddick-like wasteland? Hmm...
Diodes are backwards. The way they are now, they create a dead short across the batteries' leads.
The small black wire goes to the charger's negative lead. One end of the diode would go just on the fatter wire.
Nobody's bothered to reverse engineer that BMS, so I can only take an educated guess at the parts. The black things, I think, are simple ICs made to measure cell voltage and control power to the bleeder resistors (round blue things). The big black rectangle keeps track of the voltage of the individual cell groups and tells the smaller ICs to feed power to the resistors to lower the highest-voltage cells so it can let power in through the charger and charge the pack. It repeats this until the cells are balanced. The four metal bars are shunts. The BMS uses them to measure current and activate the overcurrent protection if it gets too high.
Okay. In that situation, the lowest-capacity packs would cut out first. Then the diodes would start conducting the remaining pack's power. Of course, since the smaller packs have cut out, you'll only get the voltage of the remaining pack.
Make sure all of those cells are 7V or more. Ones that are less generally aren't good anymore.
Uh...the Prius cells' terminals are all exposed after you take of the lid, I think, so it should just be a matter of unscrewing a few of the connecting strips of metal and putting wires in their place.
Hehe...yeah, those fuses are pretty big. I watched and episode of "How it's Made" (I think) where they showed the construction of some HV fuses made for grid use. The biggest one I saw looked somewhere around 20" long and about as fat as my calf.
No, 451A probably won't blow it. Typical fuses are designed to carry their rated capacity indefinitely, fry after something like 5 (or was it two?) seconds of double their rated capacity, and exponentially less time as currents get higher. Also depends on the type (fast/slow blow), brand, and make of the fuse. It WILL, however, blow almost instantly from the type of current three 125Ah batteries will make in a dead short, which is what matters.
100 mile range is good, but I'm saying you can't do it on a $3,000 budget. Maybe if it was a light motorcycle and it was a $3k budget for the batteries alone, but, otherwise, I haven't found any battery cheap enough to pull that kind of thing off with.
LOL, torque FTW. 'Member the comment I made about a twin-X5 bike with a scant 25-30mph top speed but 1G of thrust off the line? :P
I like sepex for the good torque at low speed, but also for the ability to weaken the stator field and gain top speed at the cost of a little efficiency.
After all I've read about regen, I don't think it's really worth the extra $ to pay for a controller capable of it. It's a good novelty, saves on brake wear, and DOES extend your range a little, but it just doesn't do it by very much. Someone did a 1600ft descent with regen on their ebike and only gained 0.35Ah out of it. They used 4.6Ah going up the hill.
Keeping it simple? Etek-RT, Alltrax controller, and a crapload of cheap Thunder Sky LiFe. We'd have to attach the connectors on the fat wires, since few have the equipment or skill to crimp/solder wires that big.
Problem is, a couple places already have a kit like that, sans the batteries. :/
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LOL. You must have watched Riddick tonight too. I like him!
Pings in series
Damn! Thats what I thought. Aerowhat pointed me to Fetchers post
http://endless-sphere.com/forums/viewtopic.php?f=16&t=1312
Now I think I get it
Reverse engineering is how I try to figure a lot of things out. It usually doesnt work.
Huh? Oh, the diode wasnt shown in your BMS pic?
Kinda like this?
Pings in parallel
That makes sense. Until the lowest-capacity packs cut out, I will have more power. Then the large-capacity pack does all the work. Thats better than without the extra pack.
Im confused. Just so we are on the same page... We are talking about three Ping packs (2-36V/10Ah and 1-36V/20Ah) in parallel without additional diodes? It seems to me that when the two smaller packs of Pings get too low they will just shut down and the remaining pack will provide the only power???
Why does a diode have to start conducting at all in this case???
Prius NiMH Battery...
I asked the guy what the resting voltage was, but but I dont think the pack has been opened. He said that he couldn't test the resting voltage.
Sounds legit. And, hes local. No word on my counter offer yet as of 8am Sunday norning.
Fuse...
I was thinking I could use them to power the pyramid LOL
Okay, add 5 more damn pounds to the weight of the Etank. I will use them.
Ekits...
The battery budget is up to them. The $3000 kit does not include Batteries. So we just say, "Up to 100 miles between charges, depending on terrain, weight of bike, weight of riders, and type of battery used." They can buy a 40 grand battery pack (Valence Technology Inc. 18 lithium phosphate rechargeable batteries valued at $2,030 each) and go 200 miles if they want to. Or, buy 4 $50 SLAs and go 1-1/2 miles LOL
Cant they just crimp the 2/0 cable connectors with a hammer, so they can cut the cables to the length they want? If we preassemble the cable ends, they may be too long or too short for their bike.
I used a 3' bolt cutter and squeezed til the connector was flat, without cutting the connector. Worked great! I tried to pull an end off with a 2' screwdriver crowbar with the wire in a vise and it didnt budge.
Etek-RT and Alltrax controller? Those two alone are 2 grand! Maybe as an upgrade from the basic kit option? And a crapload of cheap Thunder Sky LiFers if they choose them at additional charge. Just how many is a crapload? What size is a 5kWh crapload? Custom made battery box available at additional cost.
Hmmm, 4.6Ah used going up the 1600' hill and 0.35Ah gained from regen going down the hill. 7.6% regen. Selling point or waste of money?
Im thinkin'
Brushed PM and 48V Curtis base kit... $3000 plus batteries and shipping
Or, my new GE GC motor that I can now get for 100 bucks each in quantity?
Another great selling point is that we will offer a 24 hour technical hotline (your cell phone number). Can you answer business calls at skool? :jawdrop:
Ive searched and cant find any. Where?
No problem though, our lawyer
will sue them for patent infringement violations.
And, those other places dont have our special hotline guy... YOU! I am too funny!
Nope. Been scouting the Super Smash Bros. board for competition. Prolly came up with that because I read a LOT of sci-fi in general. Whole working-at-a-library thing and all. :/
Can't see either of the pics...?
Uh...no? In parallel, the internal resistance of the packs will make the bigger pack supply about 1/2 of the total current supplied by the four packs, so they should all shut down around the same time. My problem is with the LVC FETs. If they can't take a few volts backwards (the difference between the pack they control and the highest pack in the parallel group), they'll fry. Using a diode in series with the P- lead on the BMS would protect against this, but would rob a volt or two. Diodes are notorious for this. It's why I'd favor a paralleling of all the cell groups and using a single BMS. It would take a while for all the cells to get balanced in a pack that large (that BMS only balances at something like 100mA), and would need two chargers to charge in a reasonable amount of time (BMS can only handle 5A charging current, so you'd need something like a 20-40A SLA charger to bulk charge the pack first, and then use another charger to finish charging and balancing the pack), but it solves all the problems with the BMSs interfering with each other.
In series, the diodes across both of the battery leads are what protect the LVC. In normal operation, a pack's voltage keeps much, if any, current from flowing through the diode. Once a pack cuts out, the diode doesn't see that voltage anymore and starts acting as a bridge for the rest of the series string, bypassing the pack it's on.
There seems to be something of a long-standing debate on the conductivity/strength difference between crimping and soldering. I stand on the soldering side if I have to pick one, or both if the connector allows for it. Crimping is easy enough, but heavy copper wiring is such an effective heatsink that you basically need an acetylene torch and quick hands to solder a connector onto them. Also it's a good way to get 3rd-degree burns if you're not careful.
I can't prove a solder joint is better than a crimped one without some really sensitive equipment, but I know it'd be awful hard to make stronger than a solder joint. I soldered part of a brake cable to itself to attach my bike's torque arm with, and can lever it out of a tightened vice with an automotive screwdriver and not have it break.
Would probably help the kit look more like a kit, too. Makes it look like there's less work involved, which is really only true in a technical sense. ;)
$2k? Eh? Etek-RT can be had for $500 and a pretty powerful Alltrax can be had for another $500-$600 depending on voltage...
A 5kWh crapload of TS batteries is 16 (48V) 100Ah cells at like $240 and 3kg each. So 80kg and nearly $4,000. Or 24 (72V) 70Ah cells for faster bikes (see: faster than 55mph).
Problem is, TS cells are only capable of 2C. 200A isn't all that much for a motorcycle, especially on only 48V.
Regen is definitely a selling point, but the question is whether or not it's enough of one to warrant the extra expense for the controller.
LOL, GC motor too much of a pain without built-in faceplates.
I don't even own a cell phone. Dunno why?
Electric Motorsport sells a kit. As does Cloud EV. And EVs USA, albeit kind of overpriced.
I think our lawyer's frikkin' laser-equipped sharks might be able to do something about them, though. B)
Back to scouting for competition...
The author of this post isn't responsible for any injury, disability or dismemberment, death, financial loss, illness, addiction, hereditary disease, or any other undesirable consequence or general misfortune resulting from use of the "information" contai
Must be nice to get paid to read at work. I suspect you read more than just science fiction and play video games. They dont teach the kind of stuff that you know and do in Hi Skool.
You were replying while I was rererererereediting. Should be able to see all the pics now.
Paralleling with a Single BMS...
Since you said that it would be okay... Im thinkin, just parallel all (SLA and Ping) together, then disconnecting all for charging them individually. Its too technical for me to put them in series or paralleling them with just get one big BMS for all the cells. Charging individually would charge them all faster and the cells on each pack would balance faster.
Series with Diodes...
I finally realized what you were saying when I saw Fechter's drawing. I was just confussing myself with my drawings.
Okay, P- to P-? Or?
Does this look correct so far?
Ekits...
In racing, I hear they use 5 ohms resistance at every crimped connector as a guide. Not sure what I am going to do with the Anderson 350s. I bought another one. Didnt know they are genderless and I need two. Looks like they have to be soldered. Soldering is better. Crimping is just easier. I have an oxy/acetylene torch. I have gotten a 3rd-degree burn using it. Didnt realize I was burning/melting my flesh til I smelled flesh burning. Took a year to heal. Silver dollar white scar 20 years later on my forearm.
Would have to come up with some universal cable lengths and solder them up to put in the kit. I guess just make all them cables a little longer so one length fits almost all motorcycles?
Etek-RT and Alltrax would eat over half of the production budget of $2000 per unit, at $1100 for both. Might be able to get the rest for $900.
What about if they are paralleled. That would double it to 400A, right?
I think we would have to work in the 48V range max. Higher voltage controllers cost big bucks. Harder on motors at higher voltage?
Sepex Slut!
Are Etek-Rts regen capable?
Gotta check out these kits closer, but I dont see any of them offering the Etek-RT. It doesnt look like their kits are complete, plug and ride? No motor mounts? No battery mounts. No custom LINK battery box!!! Those kits seem awefully cheap from my POV. We may be out of business before we even get started. We cant compete with their prices. They are selling their kits for less then we can put ours together for. Not enough profit margin for all the work involved. And, you want the best damn motor and controller on the market. Why havent you mentioned twin X5s yet, you G freak? :)
Why should customers buy our kit at twice the price, instead of EMs, Clouds, or EV USAs?
We have to either offer a niche hi end product at twice the price or undercut their price.
I am hearing an Hylian accent in your typing. Where do you live? Roxbury, MA? Hell, you can ride that awesome S-Go that you are riding again, CONGRATS, to MIT then.
Im in Los Angeles, California, USA, Earth (3rd rock in the) Sun Solar System, Milkey Way Galaxy, The Universe or Multiverse (whichever theory you choose to belive).
The arrow points to my house :)
http://home.honolulu.hawaii.edu/~pine/phil120/galaxy.mov
May the force be with you Sir Link Skywalker of Hyrule!
Reach for the stars! You can defeat Ganondorf with your mystical Master Sword, Boomerang, and Light Arrows!
You possess legendary humbleness, bravery, and knowledge. You are the rightful bearer of the Triforce of Courage.
Thanks for rescuing me electrically, Sir Link! :)
Heh. Yeah, I read stuff like technical manuals when I'm assigned to be cleaning up the nonfiction area.
Don't know if any BMS like that exists. However, the Cycle Analyst has a LVC feature if the throttle is routed through it. This could be used to cutout the packs if you were to bypass the BMSs.
The BMS only occupies the negative wire. Like so:
(Discovered how hard it is to draw with a trackpoint...)
Diode like that would go on the negative wire, forward biased. I'd prefer the Cycle Analyst approach, though. Simpler, and doesn't cost voltage. Not to mention diodes that big tend to be pricy.
5 ohms would be pretty bad for a power connection. I'd expect a join the size of a SB-350 contact would be somewhere around 0.0001 ohms at the most. Prolly could add another zero or two.
Likely. Figure a foot or two of excess wouldn't be too hard to deal with.
Yeah, except for the batteries, the motor and controller are the most expensive single components in a conversion. $900 would be more than enough for everything else (wires, throttle, fuses, connectors). Even $200 should be enough.
Yeah, then they'd be capable of more, but the pack would also be twice the size. I think we might be well over the limit of what can be fit in the average motorcycle at 200Ah.
Higher voltage is only a tiny bit harder on BLDCs, but brushes have to be replaced more often at higher voltage. Not really a problem, since it should only be a yearly thing at MOST at reasonable voltages.
Hey, I originally coined "torque whore" for use in describing myself. Hence a 25mph twin 5305 bike. ;)
Brushed motors, BLDCs (brushless), and sepex motors can easily be combined with regen. Little harder with induction, but their controllers are far more complex, anyway. I hear it's possible with series, but difficult and not very effective. I think it has to have power applied, removed, and then quickly stuck into regen before the field collapses. This is repeated lots of times per second.
Problem with mounting is that it really has to be done on a per-frame basis. The number-one challenge of a conversion is placement of the batteries, the number-two is mounting the motor. The rest is really just a bit of wiring and bolting stuff down.
Haven't mentioned twin X5s 'cause even they aren't really capable of the power output a real motorcycle requires. I put the cap on an X5 at 10kW peak. One of the new Mars motors (Etek-R/RT) is probably capable of 30kW peak.
Um...Prolly could get away with same-priced stuff if we offered good customer support. 'Cept I hear Electric Motorsport and Thunderstruck already do, and I'm either at school or work most days.
Yes, hearing an accent in typing makes total sense. :P
LOL, I was wondering if Roxbury was a real place...*hums "What is Love?"*
The author of this post isn't responsible for any injury, disability or dismemberment, death, financial loss, illness, addiction, hereditary disease, or any other undesirable consequence or general misfortune resulting from use of the "information" contai
The Etank lives!!! I ran the bike off the ground tonight. Kinda hot wired it... No Andersons, no fuse, and no deadman. Just a loose positive battery cable so I can pull it off if something went wrong.
Wired the 12V/50A toggle switch at 36V to activate controller and contactor together, and bypassed the fuse. Pigtailed in another connector for powering 36V accessories later.
The used controller, contactor, and potentiometer worked flawlessly. I got lucky, $150 for all 3. You never know on ebay.
I haven't ever checked the batteries, but I had tons of power! I tried to hold the rear tire from spinning even at 1 RPM... Impossible! Once the power is put to the motor, the wheel spins. Can you say TORQUE WHORE? :)
Seemed like the rear wheel was spinning 100 mph at WOT. It scared me to leave it wide open for more than a few seconds at a time.
The rear wheel is so out of balance and flat that I had to hold the 400lb bike to keep it from hopping off the stand.
I need to neaten up the wiring, add some fuses, fix the rear flat, true up the rear rim, balance the rear wheel assembly, charge the batteries, fabricate foot pegs and rear brake foot lever. AND THEN I CAN RIDE IT!
Thats fechter's BMS series drawing. Okay, the BMS only occupies the negative lead.
LOL!!! Delete your ugly drawing. In fact, would you please delete all pictures that you posted so the page will load faster on my end.
I will take care of all the drawings for our kit's assembly manual.
It was .sumthin5 ohms resistance for crimped connectors. I cant remember. That was back in the late 70's.
Well, Torque Whore is MY term now. What type is your hub motor on the S-Go?
Ekits...
2/0 stranded cable is ~$4 a foot.
I'll handle mechanical stuff (mounts for motor and batteries), you handle the technical electrical stuff.
We can use email for technical advice and good customer support.
I think Sepex motors are more trouble than they are worth.
Okay, any motor with brushes may be out. Customers are not going to want to change brushes.
What motors dont have brushes?
Obviously Brushed PMs do.
What about
Brushless PMs? Duh! is there such a thing?
Brushless BLDCs for maintenance-free? <--- Sounds like it doesnt have brushes LOL
Series for the torque whores?
Sepex for efficiency?
Induction top-of-the-line? Is induction AC?
What type of the above motors are Mars motors, Etek-R/RT?
Still wondering about batteries. Once we narrow it down to one motor for all, most liely the Etek-RT, then we can narrow down the controller and battery pack options.
If we only sell hi end kits we illiminate 95% of our potential customers.
We have to undercut everybody elses price to sell in volume. Less profit per kit, but more profit overall.
What is Love? Love is doing crap you hate to do for people you love. Thats what love is.
LOL, wouldn't be surprised if it WAS spinning close to 100mph. RPM dependent on load and all. ;)
Can only delete the BMS one. The others are being used elsewhere.
*yells to moderator* DAVID! We need pages up in this forum, plskthx. :)
It's a Golden Motor. Quite heavy at like 20-25lbs. Doesn't get hot, though.
Brushless PM (aka BLDC [brushless DC]; technically 3-phase AC) and induction (VFAC). Don't think it's really too much to ask for a brush change now and then, though. It's really all the technical maintenance an e-motorcycle should need, and it's way, way less than what a gas needs.
The Mars motors are brushed PM. The RT (ME709) is the same as the R (ME708), but with more windings (and therefore a lower RPM/V but higher lb/A).
Oh, and it looks like something of a solution in regards to balancing/charging a bunch of LiFe showed up here:
http://visforvoltage.org/forum/4885-introduction-hipwoer-lifepo4-balancing-charger-bms-bms-charger-not-cells
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I am like a kid learning to walk for the first time here. This is fascinating. There is so much info that I am overwhelmed by it all. I have learned so much (crawling), but I really know very very little. You have been so patient with me for over 7 months now.
I sincerely thank you Link for all your help. I think we have developed a friendship? I know I like you and its not because I am so impressed with you knowledge and ability.
I was very careful not to overrev the motor since you said it could spin faster and faster until it blew apart. The test sure was alot different than with the little twin brushed PM motor test. They maxed out quickly and stayed there. I am curious to know what the MPH/RPM is so I bought one of the $5 cycle computers to mount on the rear wheel.
I was doubtful about potentiometers at first. Lets say I was optimistically skeptical :) I can understand how a 1-5V throttle can change the RPMs... more voltage from the throttle equates to the controller outputting an upscaled amount of voltage to the motor. But this ohms thingy shouldn't work. There is nothing actually flowing through it. Just potential resistance. The name itself says it just has potential, but nothing is really there :) Its cool how the controller measures the different resistance levels (nothing) somehow from the potentiometer and then it adjusts the voltage output to the motor accordingly.
So, in a 0-5k controller, 0 is stopped and 5k is WOT? And, in a 5-0k controller, 5k is stopped and 0 is WOT?
I see a potential problem with potentiometers. No pun intended. If the pontentiometer malfunctions and the 0-5k controller senses too much nothing, then the motor will just keep going faster and faster, thanks to nothing. "Nothing from nothing means somethin'!" But, if the potentiometer doesnt send enough nothing, then the controller will do nothing.
No problem. I delete all my pictures, once I think you have seen them, to save time loading. If this page gets too long... Cell phone video test 3? I like hiding here in the test area. BTW, you stalked me. I was here first. I need an adult! :)
Golden Motor hub motor... Heavy and doesnt get hot equals longevity. Good choice.
Hub motor Emotorcycle kits? Just kidding :)
Have you seen this site?
http://www.instructables.com/id/Electric-Bike-Hub-Motor---How-to-Replace-a-Hall-ef/
Just out of curiosity, why did you grind down your rear axle shaft and add those big wires?
Oh, BLDC means brushless DC. Makes sense. :)
I think ACs are too involved for startup kits.
I disagree. I dont want to change the brushes. Customers who cant change their own brushes can ship the motor to you and you can change the brushes after skool and ship the motor back to the customer. Now that would be great customer service. :)
So, I am down to an Etek-RT (extra torque) or a big BLDC PM (simple, durable).
I know. You like the Etek. But give me your top two choices of BLDC PMs... please?
That sounds like an awesome charger, as long as it comes with the BMS and 32 prewired wired cells. Where can we get these complete setups in 48V cheap?
Sounds like several chineese sellers are doing self cell charging
These are cool.
http://www.goldenmotor.com/batterypack.htm
If I were going to build a battery pack for my own Emotorcycle or Ecar, if I knew how to, I think I would like to use BMIs. Screw terminals! No soldering, whoopee! "M6 threaded terminals so they are easy to bolt together to form battery packs of any voltage or capacity (no need for a battery tab spot welder). Simply bolt them together with copper link bars (available separately) or eye terminals and wire."
3.3V10Ah. Rated discharge is 200 amps peak (20C) and 120 amps continuous discharge rating (12C).
"fast re-charge capability which is rated at 3C (30amps)."
You likey Linky??? Me likey!!!!
THE PERFECT BATTERY FOR MY ETANK!
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=280274842272
I wrote the seller inquiring about the price of 12 cells, link bars, connectors, VMS, and charger with shipping. He wrote me back... Ouch!
Wanna buy a ton of cousin PoLi's slightly used batteries cheap?
http://www.electricrider.com/batteries/eonyx.htm
Regarding your balancing/handling problem on the S-Go...
If you are BOW-LEGGED you can do this :)
Ha ha ha ha, I'd forgotten about that pic. Fly, Shamu, fly! XD
I suppose as much as is possible over the internets.
As for the pots, the 3-wire ones act as voltage dividers. There's 0V on one end and 5V on the other. The controller measures the voltage potential across the 0V lead and the wiper. At rest, the wiper is close to the 0V lead, so there's no potential difference. As you move it, it gets closer to the 5V lead and has a potential against the 0V lead.
For the 2-wire pots, they work on the same concept, but the other part of the divider circuit is in the controller.
Eh...you posted before I saw it, but I was here first. Mutual stalking? Hmm...
The hub idea isn't bad at all. I've seen hubs made for it, and it would defnitely ease installation by a lot. Not to mention make more room for the batteries.
Halls I can replace. Figuring out whether it's a bad hall or a bad connection is the question. I figured it was a connection at first, given the sporadic behavior, but I'm starting to think it might have blown one of the halls, too. Test for that later...
Hmm, I dunno. Anyone capable enough to actually put the thing together is definitely capable of changing the brushes. It's pretty much just a matter of taking off the dust cover and unscrewing a few screws. I guess a good difficulty equivalent would be changing an air filter.
Uh...there's only one BLDC big enough that I know of that can move a motorcycle. It's another one of the Mars motors, known sometimes as the "brushless Etek". Problem is, there aren't many controllers that can use it to it's full potential, and not enough of them have been used to really figure out how well they work. Initial tests put it as being somewhat anemic when it comes to performance, but that's with the somewhat underpowered Sevcon controllers. Kelly makes more powerful ones, but I don't know how capable the motor itself is. Either way, the controller is going to be a lot more than an equivalent brushed, given that there are roughly six times the power components in a brushless controller.
The chargers ARE the BMS. You shouldn't need overcurrent protection if the packs are matched to the controller. All that's needed for the batteries is an LVC board. Prewired, I think, won't be happening. Besides, nut/bolt terminals are used on all the bigger batteries, which is easy to deal with.
We don't know where Golden Motor's stuff is coming from, but it's definitely coming used. Someone went through like three packs, all of which had scratches and dents. Same with ebikes.ca. They were going to stock them, but all the crap they sent them wasn't new.
Yah, BMI's good stuff. You'll pay for it, though. I was thinking about making a pack out of their cells, but, yeah...not enough cash for a decent pack of raw cells alone, let alone charger and BMS. Plus shipping from Australia would be no small sum. Plus you'd want at least 3 parallel for good range.
Damn, I didn't know LiFeBatt's stuff was so pricy. Over $2/Wh! Le gasp!
Heh. That wasn't entirely ruled out before I started building the thing. I figured it would take too much effort to make up a sturdy mounting bracket.
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Mutual stalking? I think that is called marraige :sick:
Pots...
So both Pots and Voltage throttles use voltage. Voltage throttles complete a 0-5 Volt circut to the controller.
With Pots, the controller measures the potentional difference in the internal voltage between the wiper and 5 Volts?
Like this?
Ekits...
Okay, okay, Im convinced. BLDCs are out. Are we narrowed down to the Mars ME-0709 brushed PM Etek RT?
Do you know the RPM and torque (lb/A) differences in the R (ME708) and RT (ME709)? Is it enough to make the $50 price difference worth it?
In those seller's kits, they all basically come with the same accessories, except EVUSA offers the $80 PB-5 Lever/Cable Throttle...
EM kits plus $50 shipping
Mars ME-0708 Motor and Alltrax AXE 4834 24-48V Controller (300A)..... $1050
Perm-132 Motor and Alltrax AXE 4834 24-48V Controller (300A)............ $1455
Perm-132 Motor and Alltrax AXE 4844 24-48V Controller (400A)............ $1520
Perm-132 Motor and Alltrax AXE 7234 24-72V Controller (300A)............ $1610
Perm-132 Motor and Alltrax AXE 7245 24-72V Controller (450A)............ $1720
Perm-132 Motor and Sevcon Millipak 4QD 24-48V Controller (325A)....... $1580
CEV kits plus $?? shipping
Mars ME-0708 Motor and Kelly ???? 24-36V Controller (300A).................. $999
Mars ME-0708 Motor and Kelly Rgn KD36301 24-36V Controller (300A).. $1029
Mars ME-0708 Motor and Alltrax AXE 4834 24-48V Controller (300A)...... $1119
Mars ME-0708 Motor and Alltrax AXE 2434 12-24V Controller (300A)...... $1234
Mars ME-0709 Motor and Kelly ???? 24-72V Controller (500A)................. $1099
Mars ME-0709 Motor and Alltrax AXE 7234 24-72V Controller (300A)...... $1269
Mars ME-0709 Motor and Kelly Rgn KD72301 18-90V Controller (300A)... $1049
Perm-132 Motor and Kelly ???? 24-72V Controller (400A)........................ $1999
Perm-132 Motor and Kelly Rgn KD72401 24-72V Controller (400A).......... $2049
Perm-132 Motor and Alltrax AXE 7245 24-72V Controller (450A).............. $2269
ADC-L91 Motor and Kelly ???? 24-72V Controller (500Amp)..................... $1899
D&D ES67A Motor and Kelly ???? 24-72V Controller (500Amp)................. $2269
EVUSA kits plus $41 shipping
Mars ME-0708 Motor and Alltrax AXE 4834 24-48V Controller (300A)....... $1250
Perm-132 Motor and Alltrax AXE 4844 24-48V Controller (300A).............. $1495
Perm-132 Motor and Alltrax AXE 7234 24-72V Controller (300A).............. $1995
Okay, question time...
1. Based on the motor and controller combo, not the price, which kit would you buy if your were building an Emotorcycle? Why?
2. Based on the motor and controller combo, for the best price, which kit would you buy if your were building an Emotorcycle? Why?
3. Which seller do you think sells the most kits? Why?
4. Which kits do you think are each seller's best selling kit? Why?
5. Which kit do you think has been sold the most of all of the kits? Why?
Batteries...
Oh. "..And we have built the BMS into the charger"
I believe dy-power is selling those hi-powers on ebay
http://cgi.ebay.com/36V-20AH-LiFePo4-BATTERY-BIKE-MOTOR-SCOOTER-Hi-POWER_W0QQitemZ170269499482
How do I match the batt pack to my 400A controller? Batt packs use Volts/Ah and controllers use Volts/A???
Is there some Nuetonian formula? ((Ah^3.9/A^.007) X W/D)^2/(Pi X EM^2)? :?
Doesnt most of the controllers have an LVC built in? Or, are you talking about prewired individual cell LVC?
Me likey nut/bolt terminals !!! :)
BMI's... US Dollar
Cells 3.3V/10Ah $42
VMS $60
Charger $335
Shipping $40
I hear that 14Ah will be replacing the 10Ah, thanks to the Electric Car company changing their requirements. Armin at BMI confirmed this in an email to me.
http://www.aeva.asn.au/forums/forum_posts.asp?TID=265&PID=2439
Trying to find out the new specs now.
Oh really? 3? For what? Ebuses :) EVs? Emotorcycles? Okay, hmmm....
Thats 36 cells at 39.6V/30Ah. Thats a $2500 battery pack with 3 VMSs and 3 Chargers.
My plan is to build a pack setup that I can I can expand in parallel to 2, 3, or 4 packs and transfer to the next prototype.
Apples and oranges? I am beginning to think that $/Wh is shortsided thinking...
Shouldn't we be looking at the cycle life... 10,000 cycles?
Shouldn't we be looking at the years of service... 25 years?
Shouldn't we be looking at the Peak Amps... 200A peak?
Shouldn't we be looking at quality..... no duct tape or celophane?
For a 1 or 2 year bicycle, no.
But for a 100,000+ mile PHEV, BEV, GEV, or MEV, then yes.G
GEV and MEV are my terms, soon to be patented designs and copyrighted acronyms. Can you guess what they mean?
These are interesting...
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=280274445654
What the heck are these?
http://cgi.ebay.com/A123-6-6V-4600mAh-30C-LiFePo4-Battery-Free-Gift_W0QQitemZ350104002477
Shockley?
http://cgi.ebay.com/Shockley-LifePO4-Complete-Battery-Pack-Kit-24v-10ah_W0QQitemZ150301872661
The Etank...
Top racers realize that using a low amp switch creates resistance and actually reduces power.
I did some research on my monster K-1 450A fuses and it looks like they will work fine.
I am leaving out the Anderson connectors. Too much trouble. Instead, I am going to buy one of these 190A/1000A switches as a deadman switch.
Golden Motors...
They could be reconditioning their defects? Or, maybe because most of the major cities in China are now outlawing bicycles within city limits, they are dismantling new and used Ebicycles and selling them to the US? There are more bicycles in China than people in the US. :)
Speaking of "HalfLiFe" packs, what brand did you buy from the fellow ESer that had damaged cells?
The S-Go... Link---->
Most ebikes I have seen have the pack on the back rack. Seems like a sturdy mounting bracket is simple... 4 "L" brackets from the hardware store and bolt/mount them on the crossbar? Twin packs in parallel!? 114 mile marathon?!
Are you doing good in school, young man?
The Future...
Heres an interesting high-end Emotorcycle link that Armin included in his email. There is a cool vehicle comparison calculator at the bottom of the page.
http://www.enertiabike.com/
Updated PRs on the big batt companies...
http://www.aortacity.se/Items/Li-jonTillverkare.htm
I am probably heading to Vegas to play some poker for a few days soon.
See you later, my internets friend.
Ya. It's a simple circuit used a lot in electronics to obtain a precise voltage, too. Most are technically "voltage" throttles, in that the controller uses the varying potential of the signal wire to determine throttle, they just have different methods of varying the voltage. The only one that isn't, I think, is an inductive throttle. I haven't actually looked up how it works, but I have a pretty good idea based just on its name.
The voltage constant difference between the ME motors isn't important so much as the implications of being able to run higher voltage with a lower constant. 36V isn't enough to run a motorcycle period, and even 48V is kinda pushing the lower limit. I'd bet the 708 could be run on 72V, but gearing would become an issue. I'd pick the 709.
1. D&D ES67A Motor and Kelly ???? 24-72V Controller (500Amp)................. $2269
I'm guessing it's more powerful than a Perm (which is slightly small for anything but a commuter bike), though likely not as efficient. If I had my pick of parts I'd use twin Agnimotors and a 96V 1,000A Kelly.
2. Mars ME-0709 Motor and Kelly ???? 24-72V Controller (500A)................. $1099
It's a good motor, and 500A makes for a decent, semi-sporty bike.
3. EVUSA's stuff is a tad overpriced, so mebbe not them. Since EM doesn't have much in the way of choice, probably Cloud.
4. EM: The first one. There isn't much difference between that and the higher-priced ones, IMO.
CE: The one I picked.
EVUSA: The 708. There isn't going to be much difference between an Mars on 300A and a PMG on 300A.
5. Probably the one I picked. That's about as powerful as it gets for that amount of money, and the efficiency isn't bad, either.
By "matching" I meant picking a controller that won't overtax the batteries. Like a 200A Alltrax on 100Ah of Thundersky.
Most have an LVC, and some even have programmable ones (like the Kellys). An LVC on the individual cells is better, however, since it keeps the weakest cell from being overtaxed and getting weaker. In a pack that has all of the cells closely matched (like it should), it won't affect range any since the difference should be so small that a 1mph headwind would be a far greater hindrance. Of course, having both is best. Reliability by redundancy and all.
Only need 1VMS and charger. LiFe cells in a parallel group behave and are treated like one cell. It would only charge 1/3 as fast as a single p string, though.
And that had better be the best charger evar for that much money.
We're using your bike for reference. ;) Car would need around 24s10p or more. Average bike only needs 1p. 2p would get some really good range, though.
Yes, straight $/Wh numbers are inaccurate over the lifetime of the vehicle. Problem with $/Mi is that it's so hard to figure out. Proper BMS, drain rates, charge rates, and typical DOD levels all affect how many cycles you get. And, of course, manufacturers specs are not to be trusted. :)
I'm guessing "GEV" is "ghetto electric vehicle", and MEV is...uh..."mega-ghetto electric vehicle"?
Looks like Headways. Not sure, though, it's hard to tell (often impossible) with Chinese cells.
A 2s2p pack of A123 18650 cells. Same that comes out of the DeWalts.
Middle-end (almost an oxymoron? :P) cells. The price is about right.
But use too big a switch and the weight offsets the power gain. I hear a lot of people who see the Killacycle's connectors think they're too small, but they're actually the perfect balance between power and weight. Bill Dube was/is a member of the ES, and there was a bit of convo a while back about what to use for the contacts. I think he was using the usual silver oxide, be looking at using gold. Don't know if he ever did, but I do know that the contacts were going to cost something like $127 each. O_O
Kay. Manual contactors are often used as deadmans. They can be had in big, red button format, too. ;)
Eh. Possibly, but I didn't want to have anything that could scratch up my leg in the event I hit them while pedaling without using the batteries. This was before I found out how much cogging the motor had, of course. Plus there's still the fact that I'm not bow-legged.
I have to beat the would-be cheaters off with a stick. Actually, it's my math teacher's foam bat, but you get the idea.
Seen the Enertia. Nice, but they need to fix that 50mph top speed.
Eh. I'm not sure whether I just suck at poker or that the people I play with are so bad that they're impossible to figure out. Probably a combination of the above.
Good fortune on ya, in any case. :D
The author of this post isn't responsible for any injury, disability or dismemberment, death, financial loss, illness, addiction, hereditary disease, or any other undesirable consequence or general misfortune resulting from use of the "information" contai
Period?
Okay Sifu,
I guess I am missing some primary, fundamental law of electricity... again.
As I am understanding it, which is probably wrong as usual,
Volts effects RPMs...If I dont need to go 80MPH then why are the extra volts necessary?
Amps effects torque... Necessary for starting and hills.
Amphours effects duration... Distance!
MPH effects duration... Distance again!
And, higher Volts effects cost... $$$
Is this wrong, or just imcomplete?
I eagerly await your teachings, Sensei.
50MPH is plenty of MPH for me. Why do you want to obtain Autobaun speeds?
I agree, RT 709 is probably worth 50 bucks more.
1. D&D ES67A Motor? Ha! I knew you would pick the biggest, most powerful, FASTEST, and most expensive kit (See Autobon above) Also interesting is that you picked a "93 pound series wound motor for small to mid Sized Electric Vehicle Conversions" to mount on a motorcycle. Series wound? I rest my case. So much for the waffle motors. CEV sells that motor for $1400, but its $1220 at BPS.
93 pounds! My motor is almost as good as a D&D ES67A and its only 56 pounds. And, I can get them for 100 bucks each!!!
Oh great! There goes another three hours of my time researching twin Agnimotors and a 96V 1,000A Kelly. But I'm sure it will go 100MPH, at least :)
Why two? 1000A? 150MPH? You must know Cedric and his awesome 80MPH Aprilla with a single Agnimotor. His site states "up to 60 Volts." How much are Agnis?
OMG! 1000A kelly controller $1895!!!
So lets see, $???? motor, $1895 Controller, $3000 LiFe pack setup, plus acc... $7000 kit
Okay, back to reality...
2. Im thinking that a 709 might be too small for a 750CC chassis, but I agree as far as being the best cheapest kit available. Sounds like alot of bang for only $1100. I wonder why all the mystery with the controller. Supplier price and availability, most likely. As long as it is 500A, I guess it doesn't really matter.
3. Okay, variety is definitely in CEV's favor.
4. The top sellers
EM's Mars ME-0708 Motor and Alltrax AXE 4834 24-48V Controller (300A)..... $1050
CEV's Mars ME-0709 Motor and Kelly ???? 24-72V Controller (500A)................. $1099
EVUSA's Mars ME-0708 Motor and Alltrax AXE 4834 24-48V Controller (300A)....... $1250
5. The best seller
CEV's Mars ME-0709 Motor and Kelly ???? 24-72V Controller (500A)................. $1099
Small/Medium Motorcycle Base kit: 708 and 300A controller, ??V/??Ah Lifes $????
Small/Medium Motorcycle Upgrade kit: 709 and 500A controller ??V/??Ah Lifes $????
Sport bike/Cruiser kit: ES67A 500A controller ??V/??Ah Lifes $????
Monster kit: Agni and 1000A controller ??V/??Ah Lifes $7000+
LOL thats a huge pack with low Amp controller. Thats matching? Well, that should go 200 miles or so. But Im thinkin its nice to have available short blasts of 400A+ too. Why cant the controller be bigger and just NOT drive like a maniac, so you save the batteries?
Alot of factors must go into matching batteries with the controller?
I put a feeler out on Alibaba for my 48V/133A setup and have been emailing with a salesrep from a major China battery company:
"(name omitted): After discussing with our engineer. We think the parallel connecting with 3 packs of 48v 45AH can settle your problem."
That sounds okay to me. Waiting on a price.
Its ironic that you just said to parallel 3 packs too :)
Also, a company in Indonesia : "(name omitted): The price for 16 units LiFePO4 48V/100Ah US$4080 including shipping cost. Payment terms Telegraphic Transfer or Bank Wire Transfer. Best regards, (name omitted)"
Great price! 16 48V/100Ah LiFe packs for only 4 grand! We are now in the large Ah battery business!!! How many 48V/100Ah LiFe packs do you want at $255 each plus shipping? I will have (name omitted) drop ship them straight to you. Hell, for that price I will fly there with cash! LOL Must be either a scam or a typo, 10Ah? Most likely the former.
The only things that the BMS does is cell balancing during charging, and LVC and OCP during discharging. Nothing else, right?
Yeah, Thats why I think 3 small chargers is the way to go
LOL Yeah, $2500 for the cells and VMS, $3000 for the charger.
Yeah, forget LINKJY, llc. "Ghetto EV" is our new name!
A free 40
with every conversion kit purchase.
WoW! Gold $127 contacts? You are gonna need those for your twin Agnis
Middle-end? Is that like Butt-face?
Mount the Battery pack on the crossbar and you will become bow-legged from peddling. Peddle extenders? Just dont peddle and it will work like squeezing the gas tank on a motorcycle to hang on. With a 57 mile range you dont need peddles anyway, just footpegs. :)
I dont blame them for cheating off of you. People used to cheat off of me and the teacher would think I was the one who was cheating.
Bad poker players are hard to read. Watch their eyes, breathing, swallowing, and other tells. Just muck til you get high pairs, big slick, etc. if they ont let you see the flop for low investment. I slow play and then nailum on the river.
Thanks
The extra voltage isn't technically required, but I wouldn't try for anything past 35-40mph on 36V. Reason being, resistive losses (the primary source of losses/heat in a motor) go up by the square of the current. To make 3.6kW on 36V, you need 100A. To make 3.6kW on 72, you only need 50A. But, because of the I^2R thing, you only get 1/4 the heat from resistive losses. In a perfect world with perfect motors, you could just have 1 giant 2,000Ah lithium cell and run the motor on 3V and 10,000A. In reality, that would blow up the motor in short order.
As for the amps, consider that a motor running on 72V will be spinning twice as fast as on 36V, meaning that it could be geared twice as low, keeping the torque the same. But, say the batteries aren't the limiting factor and the motor is what the controller is really protecting. If the motor can only draw 100A, then the extra gearing means it's going to be able to produce double the torque at the wheel (PWM multiplication notwithstanding, which would make it even more).
As for cost, Wh is Wh. 72V 50Ah should cost the same (or close to) 36V 100Ah.
Natch. With that motor's winding type and sheer thermal mass, I could mod the controller and make the most wheelie-prone bike in the history of forever. If I was going to be realistic, it'd be twin 709s.
Not sure which Agni is capable of it, but Jozzer on the ES is converting a Ducati with an Agni. Plan at this point looks to be to run 90V.
48V/40Ah. Same as the Quantya, I think.
60V/40Ah. Make it a 300A, though. Wouldn't be able to fit enough batteries to handle 500A unless they're A123s.
72V/50Ah. 70Ah/100Ah options for bikes big enough to fit them.
96V/50Ah high-rate batts (A123's prolly). Same upgrade as the other one.
Though I don't see any benefit over separating motor/controller selection entirely from battery selection. Almost no more work, loads more choice.
It's not for range, it's so you don't exceed the limits of the batteris. The TSkys are only good for 2C (at least the old ones are; don't know about the newer ones), so it fits. A 10Ah A123 pack and a 300A controller would technically be matched, too.
I will envy your range. I really wouldn't be surprised to see 100+ miles out of a pack that size with speeds that low, even if it is fairly heavy and has a series-wound motor. Possibly 150 or higher with light accel and flat roads.
Yeesh, yeah, too-good-to-be-true prices + money wire = scam. No two ways about it. That's what I'd expect to pay for ONE pack that size.
Yeah, that's pretty much it. It should also have overvoltage protection during charge, though.
Yeah, but the added cost of the chargers alone would probably more than offset the cost of one bigger charger, let alone the BMSs.
Nah, normal silver-oxide plated ones are good enough for me. ;)
Butt-face comes out more like a loop or something. Middle-end comes out like you need an extra spacial dimension for it.
Dunno. It's kinda wide for that. Even if I am just using the pegs, anyway. :) Besides, have to work out a way to parallel charge NiCd for the revival of the PackCycle. Thinking I can do it by just undercharging them and avoiding the dV issue entirely, but we'll see how that post plays out...
Heh. Prolly the only reason I never bother cheating is because there's no one worth cheating off.
That's pretty much just what I do any more. They're too n00bish to figure out bluffing or when to fold at all, so the amount they bet is pretty much directly proportional to the worth of their hand. Other problem is it's only the PERCEIVED worth of their hand. E.g. they won't bet much when they have a full house because it's not a flush or a straight. :/
The author of this post isn't responsible for any injury, disability or dismemberment, death, financial loss, illness, addiction, hereditary disease, or any other undesirable consequence or general misfortune resulting from use of the "information" contai
Resistance...
Ah. Higher Volts actually reduces Ohms.
I was thinking that with higher volts is actually cheaper too... since we have so much less resistance, we can lower the Ah of the battery pack and still get equal available power?
Say, at 72V I can travel just as far on a 72V/15Ah pack as I can on a 36V/20Ah pack??? Wishful thinking?
Okay, I now have the 1.44 and .36 Ohms resistancee. What does that mean???
How do we quantify resistance to an actual amount of lost power???
Is resistance part of the efficiency rating of the motor?
Example: The Agni Motor gives up to 93% efficiency
Is efficiency simply measured by 100A in, 93A worth of work out of the motor... 93% efficiency?
What does series wound actually mean? One long wire like a string of batteries in series? Or am I confusing motors and batts? Is there is parallel wound motor?
Sheer thermal mass refers to the motor being heavy, thick, and able to absorb and dissipate heat better?
Material Resistivity (Ω-m) at 20 °C
Silver.......... 1.59×10−8
Copper.......... 1.72×10−8
Gold............ 2.44×10−8
But a big switch (and wires) adds safety! Here is where overkill is a good thing, I think. Thermal melt down is scarey... Runaway bike, customers injured, burned, or worse... lawsuits! Why be at the edge of melt down to get 1/10MPH more? Why be at the edge of melt down to go 1/10 of a mile more?
A few more ounces or pounds of extra weight is well worth a tiny loss in power. IIRC, in racing, 6 pounds less weight frees up 1HP. Better to add 6 pounds of weight than to fry.
LOL What about the inverse? A 2,000Ah lithium cell, 10,000V motor and 3A? It wont blow up, but it wont spin either? Probably wouldnt even hummmmm.
Ekits...
Small/Medium Motorcycle Base kit: 708 and 300A controller, 48V/40Ah Cheap LiFes $????
Small/Medium Motorcycle Upgrade kit: 709 and 300A controller 60V/40Ah Cheap LiFes $????
Sport bike/Cruiser kit: ES67A 500A controller 72V/50Ah Middle-End Lifes $????
Sport bike/Cruiser kit: ES67A 500A controller 72V/70Ah Middle-End Lifes $????
Sport bike/Cruiser kit: ES67A 500A controller 72V/100Ah Middle-End Lifes $????
Monster kit: Agni and 1000A controller 96V/50Ah A123 Lifes $7000+
Monster kit: Agni and 1000A controller 96V/70Ah A123 Lifes $7000+
Monster kit: Agni and 1000A controller 96V/100Ah A123 Lifes $7000+
So offer battery/controller choices seperately for each kit?
A twin 709 kit sounds good too... Wheelie whore!
Revisiting LiFeBatts one last time...
40138 3.3V/10Ah $42 cell
Please define good range? Im thinkin' a good range is 100 miles, but I think you are talking about Wbike at 50 miles? A good range is much different for Ebikes and Ecycles/Ecars. Ebikes that go 50 miles are awesome. Not too many people would want to ride a bicycle more than 50 miles at the most, would they? An Ecycle/Ecar needs at least 100 miles?
Okay, an ebike needs 39.6V/20Ah, 12s1p. 12 cells @ $42... $500 pack
My bike needs a 39.6V/30Ah, 12s3p, 36 cells @ $42... $1500 pack
Ecar needs a 79.2V/100Ah, 24s10p, 240 $40 cells! $9600 pack DAMN!!!
So much for LiFeBatts
What is the cheapest brand of LiFes with screw/nut ends, any size? Headway?
Check these ABF Batts out
Wood box better than Duct tape! And bolts and nuts!
Max. continuous discharging current 800A
Max. pulse discharging current for 10 second 1000A
Standard charging(for 6 hour): 20A.
Total weight Approx. 14Kg
Dimension L X W X H 260mm X 190 X 220mm
All the way up to:
Nominal voltage 3.2V
Nominal capacity: 1000Ah
Max. continuous discharging current 8000A
Max. pulse discharging current for 10 second 10000A
Standard charging(for 6 hour): 200A.
Max. recommend continuous charging current: 600A
Total weight Approx. 70Kg
Dimension L X W X H 1200mm X 500 X 220mm
Perfect for the motor on 3V and 10,000A :)
Optimum quoted me $395 per 48V/15Ah Lifes plus shipping
Really? 150 miles out of a 48V/100Ah LiFe pack?? Whoo hoo! FTW the marathon too!
And, I am keeping the SLAs too, So I am looking at 157 miles! LOL
I dont think you have to worry about me putting a 100Ah pack on the Etank. Your S-Go is the marathon champ.
|------------------------------------------------------------------------------------------|
Low End..........................................Middle..................."Middle End"................High End
Sorry, I have no clue how to parallel charge NiCds, sounds like they have the same problem as NiXXs. Maybe these will help...
Only charge to 90%?
http://www.rcbatteryclinic.com/parallel.html
http://sci.tech-archive.net/Archive/sci.electronics.basics/2004-07/0247.html
Cool Quantya! When you are done riding it for 2-1/2 hours at 45MPH, it folds up into a $10,000 Swiss Army Knife.
LOL, Perception is our own reality. I was in playing Bad Beat, aka Poker, and when it came time to show our hands, I sarcastically said, "I only have two pairs of 4s." The guy who lost was so sure he had won with his set that he got very upset when the dealer pushed the pot to me. He kept insisting that three of a kind beats two pair. :)
I laud you copiously!
Assuming similar speeds, you should be able to go farther, since there's more energy available.
Umm...that formula is for figuring out heat. All that tells me is that 50A going through 1.44 ohms makes 3.6kW of heat.
Take the PMG-132. It has a terminal resistance of 0.025 ohms. If 100A were flowing through it, 100A ^ 2 x 0.025 = 10,000A x 0.025 = 250W of power is being dissipated as heat.
Yah. Mechanical watts out over electrical watts in gives you the momentary efficiency of the motor.
Series means that the current flows through the armature and then the stator, as opposed to it splitting at a common power source and being shared by the two. "Parallel wound" is also known as "shunt wound". You actually know of it already; it's another name for a sepex.
Yah. The bigger the motor, the more heat it can waste and not overheat.
I've seen multi-kV motors before. Like the size of a car or bigger, and well over a million horsepower. Seen the size of some of the generators in a hydroelectric dam? Try to picture that running on 3V. ;)
Good range in the ebiking mindset is enough to get to work with a sidetrip to the store and the ability to go back to either if you forgot something. In other words, relative.
Good ebiking range is 30 miles.
Good driving range prolly above 70. Most people don't drive more than 40 miles in a day, anyway.
Told ya batteries are the most expensive part...
Headway doesn't make n/b terminal batts. That's only really typical of the larger formats, which is what we'd want to be using, anyway.
Only brand that I can think of off the top of my head that might fit the desired cost/performance aspect would be Foxxpower.
LOL, fits the GEV description pretty well at least.
$400 for a 720Wh pack isn't bad at all. Probably around the same quality as Ping's cells for that price, though.
The author of this post isn't responsible for any injury, disability or dismemberment, death, financial loss, illness, addiction, hereditary disease, or any other undesirable consequence or general misfortune resulting from use of the "information" contai
Now I realize the danger of a 36V high Amp system. Thanks to you beating it into my head, over and over. I am grateful. Thank you!
The resistance/heat potential is so great at 36V that thermal meltdown is likely to occur. 36V/100A/1.44ohms eguates to 100A ^ 2 x 1.44 = 10,000A x 1.44 = 14.4kW of power is being dissipated as heat. Thats a hell of alot of heat. Sure is alot less with a 72V/50A/.36ohms setup, only 900W of heat. Even 48V/75A/.72ohms would be alot better at 4kW.
A 36V/100A setup would make a great warehouse sized heater, if you are cold, but it doesnt make a very good battery pack for an EV, period? :)
Out of curiosity, what would thermally meltdown first on my Etank???
My batteries, wires, deadman switch, and motor should be able to handle the ohms? Not sure if the controller and contactor can handle the ohms though?
Heres a thought...
What about setting up a relay to kick in a parallel booster pack at say, 200A and above?
Back to seriesing SLAs and LiFes together and buying a new controller for my Etank to get the Volts up!!!
I was so tired last night and obsessing on that damn I^2R thing that I couldnt even figure out V*Ah=Wh. What I was trying to get at was, with the same amount of energy available, 72V/10Ah (720Wh) will go farther than 36V/20Ah (720Wh), with all other things being equal, because of the increased resistance at the lower voltage of the 36V setup.
I was also trying to figure out which complete setup is actually cheaper, 36V/20Ah or 72V/10Ah? They both use 24 3.2V/10Ah LiFe cells, 36V/20Ah - 12s2p and 72V/10Ah - 24s1p, But, the cost of the two complete setups, Cells-BMS-Charger, are not the same, because the BMS and charger for a 72V setup will be more expensive than the 36V BMS and charger. Right? Not to mention the great additional cost of a 72V controller. 36V is alot cheaper!
The 0.025ohm terminal resistance on the PGM-132 seems really low. Do you know what your S-Go hub motor terminal resistance is? What is the terminal resistance of the Mars 0709? A while back you told me how to check the terminal resistance on my motor. I cant find it. It was something about measuring the resistance across two of the terminals on my motor when it is hooked up?
Do you think $280 total including tax and shipping for 110 of these 3.2V/1400mA 3C Headway LiFePO4 cells is good price?
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=280276750885
The seller just made this offer to me. $.62Wh
I have no idea what to do with them once I received them.
I would need some way to hook them all up in a pack, a BMS and charger.
They dont look like they have solder tabs?
If you had these cells how would you set them up?
Gonna check out Foxxpower. Im checkig out those TS brick LiFes too.
Shipping will add some to it. I think I can beat $.55Wh plus shipping on 19650s.
Speaking of Pinglikes...
I am crunching numbers to figure out just how many 18650s are in those packs.
One 18650 LiFe cell is 3.2V/1100mAh to 1400mAh.
Take for example Pings 36V/15Ah pack
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=320310385630
To get that size how many cells is he using?
3.2V/1400Ah 10s10p = 100 cells = 32V/14Ah?
3.2V/1400Ah 11s11p = 121 cells = 35.2V/15.4Ah?
3.2V/1400Ah 12s11p = 132 cells = 38.4V/15.4Ah?
Are they using the charge max of 3.65V/cell
Is this market math again?
What does my relatives have to do with this? I never go to my relative's house. I dont even like my relatives!
Alright listen, you wheelie whore! GEV does not mean Ghetto EV and MEV does not mean Mega-Ghetto EV.
*My ghetto voice* G stan foe Ginraitur and M stans foe Motasicle sucka. Anz buy duh wey, a ho gits peyed anz a slught gibs it awey. NE1 peying us? Den u a weellie slught :)
Don't think you'd have to worry about a situation like that, since you'd need a lot more than 36V to get 100A through 1.44 ohms of resistance. :)
Could work for a small (like trials bike small) commuter bike. Though 100Ah is far more than you'd need for a commuter bike...
Motor commutator or windings or both. In theory, it's impossible to overheat a properly designed controller that gets even minimal ventilation, and the batteries would probably only get lukewarm in the worst of conditions.
Wouldn't need it. Just having them always in parallel would work. I've heard of SLA/high-rate LiFe hybrid packs being thrown together a few times, too.
Probably, but it wouldn't be all that much of a difference unless it was a really high C-rate system. Heat, however, would likely be a problem.
The pack's capacity is limited by its weakest cell, so this, of course, is brilliant. :P
Yeah, the 36V one is cheaper for BMS and charger reasons. But, in a large pack, it should end up not being all that much of a difference overall.
In a brushless, it's phase resistance, and, no, I never bothered to check.
Dunno about the ME motors'. The old Etek was around 0.033 ohms, so perhaps thereabouts.
You just measure the resistance between the two wires that feed power to the motor.
Based on the discharge specs, they look to be about the same quality as Ping's cells.
For a one-off job, I'd just solder copper strip to them. It takes a big iron (~45W or more), and a quick hand to keep the cells from getting too hot, but it can be done. If I had to do a lot of them, I'd make a capacitive discharge spot welder. A decent one would end up costing around $150.
He's using a different type of cell. Unknown 4Ah foil-pouch cells (he used to use 5Ah cells, but he swapped in favor of these; they're higher quality). They have the advantage of having little packing material and no wasted space between them, so they can be fit in a space very efficiently. Unfortunately this also means that they are rather intolerant of impact, hence my (and everyone else who's bought a Ping pack's) battery box.
Ping's using what seems to now be more or less the standard for LiFe nominal voltage of 3V/cell. So that's a 12s4p pack. Unless he's using 5Ah cells again (which he could be, since I haven't been keeping track since I got my pack), he's underrating the batteries to compensate for any small lack of capacity the cells have.
Um. Nothing if you don't like them, since then you don't have to factor trips to their houses into your prospective range?
I get something or other if I ride my bike or an EV to work (both, in this case ;)), so I'm sorta getting paid. :/
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Huh? Now I dont have to worry about it? What do you mean? First you tell me not to go over 30MPH or I will die! Now... dont worry about it!!! LOL Dont worry about 100A, but I will die at 400A?
What do you mean by through?
Ah, so the motor commutator or windings are the weak Link. Pun intended.
My SLAs do have a high dicharge C rate potential, dont they? My SLAs melted the end completely off of a 12" screwdriver the other day... Ooops! Thats pretty damn high! :)
Thank you! You taught me everything I know. You coalesce the vapor of human experience into a viable and logical comprehension. :sick:
With or without the battery hooked up? Wont measuring the resistance between a live + and - on the motor with a DVM set on Ohms fry the DVM?
Not by me. See screwdriver reference above. :) I would be the first person on earth to blow up a LiFe. Not really the kind on fame that I want.
I searched for VoltPhreak and he sells them for $1.75 in bulk quantities of 50 or more. About $200 for 100 with shipping and tax... $.50Wh... getting better?
//s.p10.hostingprod.com/ [at] www.voltphreaks.com/ssl/catalog/product_info.php?products_id=58&osCsid=3449b3ff95056ed4c3aec9bb8b257ea2">
High capacity LiFePO4 18650
What size/type are Ping's cells and what is the cell Ah?
I like Ping's marketing technique... underrate his packs a little and the customers dont expect as much. Undermarketing math? Their lowered perception makes them happy customers. Ah, reality! :)
On ES...
"BTW, Li Ping (ebay Lifepo4 packs) claims that his new 4Ah cells used in his new packs have under 15mohm resistance, which would equate to about 6mohm per equivalent 10Ah capacity... better than headway IF this turns out to be true."
http://www.endless-sphere.com/forums/viewtopic.php?f=14&t=3374&start=225&st=0&sk=t&sd=a
Optimum LiFe quote:
"1,The price of 1 48V/45A pack with shipping:USD1450 (By UPS)"
The demension is about:W 290mm L 330mm H 140mm
Headway LiFe quote:
"The price of 48v40Ah pack with BMS and charger of 48v6A is 1085USD/pack FOB Shanghai.
The 48v50Ah pack is made up of 5 packs of 48v10Ah built with BMS. The max. discharging current of each single pack is 80A, the max. peak discharging current of 58v50Ah pack can be up to 400A.
The dimensions are 790*220*160mm, the weight is approx. 26.5kgs.
The price of 48v50Ah pack with BMS and charger of 48v6A is 1450USD/pack FOB Shanghai."
What does a C rate of 0.2C5A mean?
No, they have to pay you for just riding a wheelie. They dont, so you are just a wannabe weelie slught. Sorry :)
A motor with 1.44 ohms of resistance on 36V wouldn't be able to draw more than 25A, so an absolute maximum of 900W in, and rather less out. Not nearly enough to move an etank.
Your motor will not have nearly that much resistance. Probably a maximum of 0.1 ohms. Likely less. So the amperage drawn will be much greater.
We're talking about the terminal resistance of the motor. The terminal resistance is the total resistance of the lead wires, commutator, brushes, and windings, all of which the current has to go through. (The windings are the biggest source of resistance.)
Hay! I see what you did there.
You know, I've never found out exactly what kind of discharge rates SLAs are capable of. It doesn't seem to be a limitation for them so much as a question of "How much capacity do you want to lose to Peukert and voltage sag?". My PackCycle ran them up to 7C before, and they were suffering some serious sag (like less than half normal voltage).
And, yes, big SLAs will destroy anything that shorts them out. :)
:D
Without the batts. Resistance is never measured (the way a DVM does it, anyway) with power on. It throws it way off.
I dunno. Managing to destroy a 4110 is considered something like a mark of honor. Destroying an X5 even more so. :P
$0.50/Wh is quite good for LiFe, even if it is low-end. There's still that 1C discharge rate problem, though.
Underrating batts a little is good practice. ;o
Think the 0.2C thing is for charging.
Well. I can't even do a wheelie in anything but a wheelchair. >:|
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