My battery tray has what appear to be cooling fins on the bottom to direct airflow up into the battery case. Does your E-Spirit have that? For starters, I have thought about sealing off those cooling ducts in the winter. Today it was about 68 F when I went riding, and again my range is down significantly from what I see when riding in our 95-115 F temps. Installing a heating mechanism is not a bad idea, but I can imagine how much power that might consume. If I could relocate my controller inside the battery compartment during the colder weather, that thing alone would heat up the batteries. (assuming a pretty air tight compartment) And then I would relocate the controller back outside during the 100+ temps.
It is very odd. The controller and hub motor like the cool weather. The batteries like the hot weather.
Yes tearing down even the 4000li to get to the battery compartment is a huge project. I have done it once and will be doing it again in a few months.
If your charger will give the pack a bit of a "pre-charge" (also called "forced charge") right before you ride, that should warm the batteries. That, plus an insulating blanket, should make a difference.
I can't stand a long enough ride in Winter for range to be an issue, even with the 10 year old SLA pack on the Lepton. If I were going to take a longer ride on it, the Zantrex charger it uses will do forced charging - I've used that feature for years to extend range.
Sorry to take so long. I haven't located the resistor values yet but I'll try to answer the other questions.
If your charger is charging 80 volts it's way out of specs for a 20 cell charger or your voltmeter is off. That would be charging the cells to 4 volts each. Not good. My modified charger goes to just 80 volts and charges to a bit over 3.6 per cell. If you are going to try to add cells and string charge without a BMS I would expect the new cells to have a lower internal resistance and might not balance with the old ones but you could try it if you have an easy way to monitor all the other cells. It will only be a problem at the top of the charge and you would need to have the new and old cells charged to the same voltage to start with. It would be safer to charge the new cells with a separate charger. There is no need to disconnect them from the rest of the cells.
The DC DC converter might not take the extra voltage. My bike had a new one installed by the previous owner after the stock one blew. If you just add two cells in the string and hook the controller and Charger and DC DC converter positive to the most positive cell the charger and controller and DC DC converter with all be getting the increased voltage on the total pack. That is how my bike is wired. The other way to do it is to leave the charger and controller positive on the same cell they are on now and add the new cells between the last original cell and the circuit breaker. This way the charger will charge the original 20 cells and the controller logic side and the DC DC converter will be running on 20 cells just like before. A separate two cell ( or how ever many you want to add, certainly not over 8 cells )charger charges the new cells. They should balance ok with each other. Is that all as clear as mud ?
Yes, it's always easier to leave things the way they are ( if you can,Ha ) Things can go bad when you start modifying stuff.
As far as getting all the cells replaced on warranty after two years I doubt that the warranty works that way unless they all go bad mysteriously a week before the date the warranty is up. It sounds like the cells are going strong !
Hope this helps
PS On some of the other things you have been discussing. The controller usually does not limit speed although it is possible. The voltage limits speed. The amperage doesn't limit the speed either except up a hill where the controller is reaching its max amps. On the flat the amperage goes well below the max the controller can put out. If you increase the amperage of the controller you will have better acceleration and hill climbing but no more speed on the flat.
The speedo on my bike and I imagine yours is the same is just a cable driven mechanical unit driven off the front wheel. Nothing very mystical.
Hope this helped. Have fun. Garry
My battery tray has what appear to be cooling fins on the bottom to direct airflow up into the battery case. Does your E-Spirit have that?
The body panel in the front wheel well has a grill that air could get into, but behind that is a sheet metal barrier where the battery tray front ends, so not much cooling air comes in there anyway.
I have the controller sitting above the battery pack, but with the charger in between. However, the controller heat will not really get down into the battery.
But as has been alluded to further up, charging full shortly before the ride is a tremendous help in bringing the battery chemistry up to speed and heating up the whole thing from the inside. I have seen battery temp. rise some 5°C during a charge, even close to freezing temp. The best is when I have another appointment in the evening: When I come home from work the battery has heated up around 5°C too, then I charge while having supper, and by the time I need to get going again some 2h later the battery is not only fully charged again, but another 4 to 5°C warmer, and I can get the best of both worlds - excellent battery performance at close to or above 15°C battery temp., and controller and motor bask in the cold and the bike goes off like a rocket despite close to freezing ambient temp. :-) And that heat even remains till the next morning to a certain extent and gives me less trouble accelerating.
The heating is only around 115W and will encompass insulation too. And I have even figured out a way to get that in without having to take out all 6 battery blocks, two at the back were enough so I can slide my whole sandwich in from the back. Things will begin to get interesting now, as long as I can squeeze some time out of family activites...
2017 Zero S ZF6.5 11kW, erider Thunder 5kW
Leftie - Thanks for the suggestion! I often do a "forced charge" where I leave the charger plugged in either overnight, or at least an hour or two after both lights have gone green, and it makes sense that doing so would add heat to the pack, which will help in colder weather. The 4000li has a small rubber insulating blanket over the entire pack, and now I understand why.
ScooterGuy - Yes my charger will charge to about 79.5 volts consistently when I let the charger do a "forced charge" as mentioned above. When both lights initially go green, my voltage is around 70.0, confirmed both by my onboard voltmeter and a handheld one. If I leave the charger plugged in over night, or for any long duration after the initial green lights, it goes into pulse mode, or forced charge mode, and will bring all cells up even higher. When I had the bike apart I measured each of my cells individually, and at 79.5 volts, I did have eight cells that were over 4.0 volts....the highest being 4.08. These quickly subsided to 3.88 after the charger was removed. My lowest cells were at 3.67 and 3.80 after forced charge.
This is very important. My cycle has a Dec 2008 manufacture date, so the cells were 2 years old when I received my 4000li (it had 14 miles on it...Showroom Display). As for balance and BMS, after about 20 miles of riding, I measured every one of my cells individually, and with my pack at 65V, every cell measured exactly 3.28. I was pretty stunned, but they balance out really nicely, and consistently. I have 13 months remaining on my battery warranty, 6135 miles on my cycle, and will test them all individually again in a few months.
ME Roller - Well you have explained clearly why my range and acceleration are far better immediately after a charge. If I let my bike sit in the cold garage overnight and then ride, my range is definitely reduced. Those packs just don't like the cold! Yes the ideal situation is a warm battery pack with a cold controller and hub motor.
Amazing..... these batteries are actually made in GBS though their sticker was still TS brand,but actually they come from GBS.
Are you referring to the picture in my post? Those are TS cells, all my batteries are TS. That is an older XM 3500li. I am interested in your batteries and will e-mail you soon. How is the BMS coming? Would love some specific details.
2008 XM3500li Mods/Kelly KBL12251/84v 28cell 40AH pack/ Variable regen brake trigger on left brake handle/Givi/Cycle Analyst/Homemade BMS
KMX Typhoon Home build (recumbent pedelec) with two Astro Brushless 3220motors/twin castle Phoenix ICEHV 160/ Cycl
Yes，mountain chen told me that even old XM3500li is GBS battery,TS don't supply any 40AH,60AH during 2008 and 2009 because all small size OEM in GBS.
GBS changed into blue battery after 2010.
Our active BMS for 20cell is ready now.
My 4000Li is a Dec 2008 model, and I have the same yellow TS 40ah batteries shown in the photo above. Are you saying those are actually GBS cells and not Thundersky? Is there an improved model available now, and will I get more range?
Yes,our CHL battery is better than no matter GBS or TS.
. I am told that with 24 CHL 40 or 50Ah cells top speed is closer to the promised 95km/h / 59mph...
Yep, I have 24x 50Ah CHL cells and I am a big guy at 120kg and I can get 92-93km/h (GPS) on a flat road and I've seen 96km/h (GPS) down a VERY steep hill with a voltage sag only dropping from 79.5v down to 74v but at that high speed I could only put out around 3.5kw because of back EMF and also you can feel the motor vibrate because you've hit the top speed.
eRider 8000w Scooter - PDT Version
72v 50AH CHL battery
350A Sevcon controller
24km: Delivered - 24 September 2011
2490km: Installed dual 35w HID lights Bi-Xenon Projectors - 27 November 2011
8313km: Installed BMS -
Thank you for all your input during the last months,I wish you a very Happy New Year!
Just passed the 7000 mile mark and have made an interesting discovery. When my 4000li sits overnight (at full charge) and then I take it for a ride in the morning in a cold state, the voltage sag is significant under accelaration. However, when I plug in around 10am, let her fully charge until 1pm and then take her for ride immediately after charging, the voltage sag is almost non-existent. Has anyone else seen this? My range is also impressive at around 40 miles, which is what my cycle was doing brand new at these winter temps. My range was up to 47+ miles in warmer May weather, and I am anxious to see if that continues later this Spring.
I'm in Oregon so low temps are common for me. I have a 3500 Li with about 4500 miles on it. I have noticed the same thing but have never done any very accurate testing. I did try to test how hard riding verses easy riding affects the range. One day I rode up to and along a ridge with an elevation climb of about 700 feet and back down with lot's of wot riding. The next day I rode on the flat and never over 30 mph with very easy acceleration and was surprised to find that the voltage started to drop off at almost the same mileage of around 30 miles. I was really expecting to get much farther going slower. When it's cold ( cold is 40 degrees for me ) I have noticed that if I just hit it hard and ride at full throttle for a few miles that the speed and power seems to increase a bit. My theory is that the batteries in the morning are very close to the nighttime low. Starting off riding hard creates some internal heat, the air temp is warming up too and warmer ( relative to batt temp )air is passing around the battery box. Then charging the pack will also cause internal heat and by 1:00 PM the air temp is up so the batteries are warming up in three different ways which will increase voltage and capacity.
I wish I could get a 40 mile range. It never gets 110 here. If it ever does I will try a range test. Most of my riding is done with temps between 50 and 80.
LiFePO4 Batteries tend to loose power drastically below a battery (not ambient!) temperature of about 15°C / 59F. At freezing temp. in the battery the voltage sag can already reach very worrying levels.
Hard riding may heat them up somewhat, maybe 3 to 4 °C / 2-3F, and charging for 2.5h at 10A can bring double to three times as much heating up. It's all got to do with battery temperature. If you cannot heat your batteries it is at least good to time the charge so it is done shortly before the ride starts.
Okay, that coincides completely with what I am seeing. When I ride immediately after the charge completes, my voltage sag is almost non-existent under acceleration. But when the cycle sits for several hours after charge, the voltage sag is significant, and range is reduced. Thank you for that explanation!! Starting in April/May here in Phoenix the ambient air temp is around 95 or 100+ Farenheit, so no wonder I see no voltage sag during that time of year. I will test my range again once it warms up and will let you know. So far this 4000li has been a dream, with 7031 trouble free miles.
So far this 4000li has been a dream, with 7031 trouble free miles.
Wow! 11,249km without any problems. I'm impressed! I have the Erider 8000w scooter (same sort of body) and I've had very few problems too. I only had a little problem yesterday where the bike 'stalled' on me. It was a one off thing, I just had to turn off and on and it worked fine again. I have about 4600km (2875 miles) of pretty much trouble free riding in 4 months.
We had a cold winter with temps around 1°c and I didn't notice any sag with the CHL batteries. But when I had thundersky batteries, anything under 10°c they REALLY sagged from 79v to 65v in no time, even at 85Amps!! I can pull 185Amps from the CHL batteries and I only see a minimum voltage of 73.5v on the cycle analyst. During normal riding at 90km/h I used about 100Amps and the voltage sits around 75.5v. I have 24 cells to make a 72v pack, but hot off the charge it's 87.6v but settles around 79.6v at rest.
I will let you know how they go when we come into winter. It's summer here at the moment in Australia.
Just an update. 7,722 miles (12,427 km) trouble free and running strong. Range is right around 40 miles, even in this cooler weather, so the lithium cells seem to be holding up very well.
Turned 9,600 miles on my 4000li today. Just replaced the brake pads and both tires a few days ago. Still have a 40 mile + range. This is the most reliable vehicle I have ever owned. The temperatures are warming up here in Phx (90 degrees) and the lithium cells seem to operate more efficiently at these temperatures.
Turned 10,000 miles yesterday and have a range of just over 40.0 miles in normal riding. (hills, stoplights) Temps around 85 degrees. I am very impressed with these Lithium cells. 40ah, Thundersky. I had expected to have replaced a few of them by now.
Is it 20cell of 40AH or 21cell of 60AH ? 40mile GPS speed range or odometer ?
20 cell of 40AH. And the 40 mile range is GPS, although the odometer is very close.
40 miles (64km) is very good. I get about 43 miles (70km) from my CHL 50Ah 24 cell (72v) pack. But I am a big guy at 120kg+. I am very happy to see you have passed 16,000km!!! That is a LOT of driving. I am hoping to get the same sort of reliability from my 50Ah CHL cells. I live in Canberra, Australia and we are now just coming into winter and this morning was VERY cold and the battery sagged to 71v under full power (8300w) just a few kilometers from home. But most of my roads here are 80km/h (50mph) and this uses a fair bit more power.
This Mr CHL guy seems to post a lot of comments about his batteries on this forum and so far I must say, they really do live up to what he claims! My 40Ah thundersky cells at 6000w would drop to around 65v and hit the low voltage cut-off. Plus in the cold weather I could only get 22Ah out of the 40Ah cells.
I still don't have a BMS on the CHL cells so I don't drain them too much.
Phil, your CHL batteries sound great! Yes the Thundersky sag under cold temperatures, but here in Phx AZ we are usually in the 60's in the winter, and 100's in the summer, so we have very little cold weather. I am right around 102kg, so fairly heavy for my bike as well, and I am 6'2" and would really like a taller windshield. Have you looked into getting one? I don't have BMS on my cycle either, and now that I have passed 16,000 km I am wondering if that complexity is worth it as these lithium cells appear to do fine without it. I never run them low, or let them overcharge. My battery warranty runs out in 8 months, so I will be watching them closely. May consider converting to CHL when the time comes if you continue to be happy with yours. Keep Riding!!
I think that the 40Ah Thundersky batteries in your scooter are fine for the 4000w system, not an 8000w system.
I went for a ride the other night at 11pm and it was -5 celcius (23F) and the voltage only sagged to 71.2v even under 116Amps! And I still managed to go 61km. The bike was fine but my fingers were freezing by the time I got home!!
Well Phil I wonder how the 5000w or 8000w cycles would do in our 110+ degree F temps which run from June through Sept. I believe the 4000w runs a little cooler (which would make sense), and my motor has never yet hit overheat cutoff in 10,463 miles of riding. My controller has hit overheat, and needs a couple of minutes to cool down when I ride 15 miles or so while climbing in 115 degree temps. I am considering adding a 21st or 22nd cell to my current twenty 40ah thunderskys. I believe you did that in the past. Would that potentially damage my motor or controller?
In answer to that Pete, Lovely. I've ridden during a hot summer day here when it was 51c (124F) and the batteries LOVE it but the motor did run pretty warm. I rode up to a lookout, it was a very steep hill all the way up with no problems. I took a few photo's then on my way down using regen all the way the motor overheated and cut all regen, that was surprising! That was the only time it hit the over temp situation. But the CHL batteries loved the heat. Compared to my ride this morning at -6C (21F) the voltage dropped to 70.8v under full power. But even with the voltage drop I can not detect any drop in performance. During the warm weather under full power, the voltage will only drop from 79.9v (resting) to 75v at full 8400w of power.
From what I've heard, a voltage drop to 70.8v is pretty good during cold weather. There are other batteries that drop even more than that?! Even after 52km yesterday (-5c in the morning and 8c during the day) I was still around 70.4v after 52km and only used 37Ah. The bike still had no problem getting up to 8000 watts.
As for adding more cells, make sure you adjust the final voltage cut-off on your charger and make sure you TIGHTLY wrap that cell to stop it from "puffing" up and destroying itself.
Wow Phil....21 Deg F to 124 Deg F. Both extremes. You are really putting your cycle through the paces, and it sounds like the CHL cells are performing great throughout the temperature range. I would make every effort to put that baby inside for the night, especially with more cold air blowing on it. (sorry wifey, the cycle is coming in) Ok, I will plan on adding a 21st cell when I take her apart again and will be sure to pack it in tightly. My current charger can already push 79 volts, which is far more than enough for 21 cells. I was more concerned about the extra voltage going through my controller. But I guess it already operates at a pretty wide range, correct? (60v to 79v) I will be adding the cycle analyst too. Currently at 10,481 miles.
How's your scooter going? I love the fact you have done 16,000km!! I'm now passing 7280km without a BMS and this morning it was -6°c and I saw the battery dip to 70.0v under full power. But the cycle analyst recorded a Vmin of 69.8v. But the bike still felt as quick as normal. It seems the battery voltage will sag as below from my notes taken over the past few months:
Voltage under full power (115Amps)
-6°c : 69.8v
-5°c : 69.7v
-4°c : 70.3v
-2°c : 70.9v
-1°c : 70.8v
0°c : 71.1v
+4°c : 71.3v
+6°c : 72.1v
I turned 11950 miles on the way to work this morning, which is 19231 Km, over 17 months. It is interesting that you mention voltage sag. In the winter, when temps were under 65F, I saw significant voltage sag and decreased range, although minimally. Now that the daytime temps are 85F on my way to work, and 110F on my way home, I still experience more voltage sag than I did 10,000 miles ago, despite the warmer temps. My range, however, does not appear to have decreased very much over those 19231 Km. Brand new I could do 45 miles, and now right around 40 miles in the same driving conditions.
Our weather is just the opposite of yours. 65 degrees in December, and 110 degrees in July. Have you ever hit low voltage cutoff? I don't believe I have ever come close. Last night after 33 miles I was at 63 volts at rest (not under load), which is 3.15 per cell average. I always stop right around that point. If a 40ah Thundersky cell is at 3.15 volts at rest, does it have significant capacity left ???? I have never chanced it.
I have however hit controller overheat a few times. But at 110F and climbing hills, I suppose that is to be expected. It takes about 10 min to cool off, and then I am on my way. Do you still plan to install BMS? The bottom line is that I am at 19231 and still going strong from what I can tell so far. I have 7 months left on my battery warranty.
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