XM-3500

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Mik
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Re: XM-3500

Mik, if you read this do you have any tests showing how much regen can extend your range?

http://visforvoltage.org/forum/2547-vectrix-reports#comment-14284

http://visforvoltage.org/forum/2547-vectrix-reports#comment-14331

There are some more that I cannot find right now.

Overall, in my regular commute the difference is hard to detect.

But Regen makes a good ABS for the rear wheel!

I would definitely not want a "Binary", "All-or-nothing" Regen system.

Mr. Mik

This information may be used entirely at your own risk.

There is always a way if there is no other way!

HalfMooner
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Re: XM-3500

:) HI: Halfmooner your post of quotes are great and I agree with you 100% on everything written. I too came to this forum after I placed a order for the Xm3500Li wich now I hear is XB3500Li or am I wrong again? The amount of missled spec's and statements For the Ah, ah, 3500Li moped should make X-treme and the dealers very upset for, they are the ones that will have to take the brunt of it. A few more missled-statements that are really a gigle, (DOT Approved 60+ mph)(2 speed automatic shift trans) (Rear wheel hub motor/No chains), now that statment can be believed. SO halfmooner I like your style,thanks for posting and Mik,the same for you post below, great job.

Thank you, joek. I believe it's possible to have strong opinions while sticking to the facts and issues at hand, and not flaming personalities. Most people here on both sides of issues are pretty good at that.

HalfMooner
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Re: XM-3500

Halfmooner - I guess we just need to agree to differ. I left off two of the four because (a) it does have ABS

I thought it didn't have ABS. If it does, which I am now assuming, I'm more than one quarter happier. ABS is far more important to me than regen.

& (b) if one takes the reading on the speedo it does do 55mph. Again, I'm not trying to convince anyone you're wrong and I'm right. Just putting forth another point of view.

When merging with 55+ mph traffic, a speedo indication of 55 is trumped by the physics of an actual 50 mph.

I really don't think a difference of 5mph transitions a vehicle from practical to "dangerously slow", nor to "illegal" - the bike has less than 5HP so it's not allowed on restricted access roads regardless of top speed.

Okay, duh, I did not know that about the 5 HP lower limit for freeways. (I'll cross that item off in my ever-growing Book of Personal Ignorance.) Still, advertised specs are advertised specs, and I persist in thinking that using an inaccurate speedo to justify a speed claim is sloppy at best, specious at worst. But maybe that's just me. ;)

BTW, what is the HP of the XM-3500Li?

I tell you what - I'll be more accurate in my accounting of missing features if you will be more specific than referring to "all these mythical features". ;-) (that's meant as good natured teasing - yes I was wrong to boil things down in that way, but your statement of the situation seemed a little "over the top" to me).

Well, I did list the four that made up that "all." I now am assuming I was wrong about ABS, so my personal revised (v2.0) "all those mythical features" list presently include only BMS, 55 mph speed, and regen. Typically, any number of things more than two can be referred to as "all." (And things one is told or that one reads which are untrue in the physical world can be called "mythical.")

Above all - we just have a different point of view. I'm not happy either that X-Treme's advertisements are written the way they are. That's just one of the many reasons I hope to create my own brand early next year. I don't wish to argue with you - but I do have an interest in seeing counter balancing view points aired.

I appreciate the civilized exchange of viewpoints. Good fortune with your own branding. May you succeed in establishing a higher level of quality control and ethics than is often found along this bleeding edge.

ebabs
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Re: XM-3500

John,

Thanks for your comments! I do believe they are all very good comments/replies to mine. You've been active for a long time with great input, so I'm not at all surprised by this. The overall point I was trying to make is that many people do base decisions based on marketing of the product and by "overstating" things or stating items to be included that are later not included does NOT help in the long run. That's all. Not sure that I'd want to drive one on the freeway, at least for this generation, but some will based on what is being advertised. There was no agenda other than hoping that continual improvement will be made.

HalfMooner
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Re: XM-3500

Please excuse this somewhat OT digression, but the quote below refers rather humorously to the topic of the differences between advertised and real claims.

I'm reading the late science fiction author Isaac Asimov's 1979 autobiography, In Memory Yet Green. I happened to read the following just after posting my last comment, above. Asimov is writing of a childhood experience in 1920's Brooklyn, from about the time he was in the first grade:

What I remember most clearly is the box of Bon Ami, a powdered cleanser . . . I would make out as much of the advertising spiel as I could and was particularly impressed by the picture on the can, which was that of a just-born chick with the broken eggshell behind it and the legend "Hasn't Scratched Yet."

I knew that Bon Ami was a scouring powder and I was very impressed with the thought of the people who made it being very conscientious and checking on all the users to make sure it had never scratched. I was quite convinced that if they ever discovered a scratch, the legend would be changed to "Scratched Only Once."

I suppose we are born with an instinctive assumption of honesty that must be beaten out of us by life, more or less painfully.

PJD
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Re: XM-3500

Actually, using a typical coefficient of drag for a motorcycle (0.80) if the scooter is reaching 50 mph, it must be producing more than 5 hp. On level ground, it would probably take a bit over 6 hp to go 50 mph or close to 11 hp to go 60 mph.

ebabs
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Re: XM-3500

Dave,

It's all good, this is opinions and experience/perspectives mixed with humor hopefully!
I was simply addressing my viewpoint on many of the issues that have come to the fore here.
BTW, whether or not you use Gillette products, it's all good! ;-)

jdh2550_1
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Re: XM-3500

Actually, using a typical coefficient of drag for a motorcycle (0.80) if the scooter is reaching 50 mph, it must be producing more than 5 hp. On level ground, it would probably take a bit over 6 hp to go 50 mph or close to 11 hp to go 60 mph.

Oops, PJD is right. Sorry guys - it likely does have more than 5HP.

If we assume an 80A peak and a 60V battery pack that gives us 4800 Watts, which google tells me is 6.43hp. Given PJDs calculations that would seem to support that (this is just a rough calculation and doesn't take into account any efficiency losses). I'll be rigging up an ammeter as part of the data acquisition for the 5 way comparison and will record peak amps seen.

Although I still wouldn't take it on the freeway...

Halfmooner & ebabs - "no harm, no foul" - we're all good. Sorry if I appeared a little too defensive (I do tend to get that way!).

All the best - and happy riding.

John H. Founder of Current Motor Company - opinions on this site belong to me; not to my employer
Remember: " 'lectric for local. diesel for distance" - JTH, Amp Bros || "No Gas.

Henry42
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Re: XM-3500

I just received the paperwork to get the title, registration, etc. The certificate states H.P. (S.A.E.): 1.9
No Cyls (I guess this means number of cylinders): 1.

I went to the following web site http://vacu-lift.net/document/company/Reference%20Guides/power.html and typed in 3.5 in the kW field and clicked calculate. The response was 4.694 hp. (I thought someone might find the number interesting).

PJD
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Re: XM-3500

Exactly, there are 746 watts (n-m/s) in a horsepower (550 ft-lb/s). But if the number in question is electrical watts going into the motor, so as John mentioned, you have to apply an efficiency to get mechanical power. Electric motor efficiency varies with RPM, but at the optimum RPMs, they are usually 90% efficient or a bit better.

The wattage rating of a motor is usually a conservative rating that the motor can be run under continuously duty use without exceeding a certain harmful temperature. The motor can put out a lot more power than it's wattage rating under shorter periods or cooler temperatures. So, it is a mistake to compare the motor's power rating with the power rating of an IC engine, which is the maximum power the engine can physically produce. They are two very different things.

HalfMooner
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Re: XM-3500

Exactly, there are 746 watts (n-m/s) in a horsepower (550 ft-lb/s). But if the number in question is electrical watts going into the motor, so as John mentioned, you have to apply an efficiency to get mechanical power. Electric motor efficiency varies with RPM, but at the optimum RPMs, they are usually 90% efficient or a bit better.

The wattage rating of a motor is usually a conservative rating that the motor can be run under continuously duty use without exceeding a certain harmful temperature. The motor can put out a lot more power than it's wattage rating under shorter periods or cooler temperatures. So, it is a mistake to compare the motor's power rating with the power rating of an IC engine, which is the maximum power the engine can physically produce. They are two very different things.

Thanks for that. It's nice that some folks here seem to actually be engineers, unlike Yours Truly. Your figures seem to confirm the guesstimate I'd made as to the HP of my old 500-watt Expresso S, which I'd pegged at 2/3 of a horse. (I forget exactly how I'd arrived at that figure. I may have seen an HP rating for another wattage bike, and scaled it to mine.)

Putting engineering exactitude temporarily on hold, could you suggest any rough, ballbark "rule of thumb" for comparing wattage in an electric bike to cc's in an ICE equivalent? (I know things like compression ratios would affect such estimates, but I'm talking "typical" bikes.) I'm wildly guessing that the XM-3500Li might be roughly equivalent to a 90 to 125 cc gas-burner.

sparc5
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Re: XM-3500

Can anyone tell me what the max output of the XM-3500li charger is? I hope to have the prototype XM-3500li BMS ready by week's end.

XM-3000...
-DC-DC converter replaced with a Dell D220P-01 power supply.
-72V mod
-Expensive bank charger until I come up with something better... Still trying.
-

TANWare
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Re: XM-3500

Hi all,
From this source, http://brucelin.ca/scooters/thumb.html , it quotes 0.5 as a scooters drag CoEfficient as a rule if thumb. For these that may be even lower as they are a bit more streamlined than say a Vespa style.

Remember 0.8 is for a naked bike that has practically no aerodynamic qualities.

davem
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Re: XM-3500- How much HP?- The feds have a statement...

While I am NOT one to think the US government understands math ,

They do have a STATED conversion of Watts to hp for electric vehicles -

As I borrowed from iloveebikes link -

http://www.iloveebikes.com/Distributorfiles/FEDregulation.pdf

There the fed says 750 = 1 hp and therefore 3500w= 4.666 hp which is < 5 hp which does mean it can not legally be on most US Interestates ...and I ALWAYS obey the speed limit to ;)

BTW, for some US states this will also make the 3500 a moped.

jdh2550_1
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Re: XM-3500- How much HP?- The feds have a statement...

Folks,

remember, Remember, REMEMBER (just trying to add emphasis - as we keep going back to 3500W as a power output figure - it's not!) - 3500W is the power rating of the motor. A figure suggested by the manufacturer for reliable (read 24/7) operation of the motor without adverse affect. AFAIK, there's no standard for the power rating - it's manufacturer's discretion. Quote too high and unhappy customers will want replacement motors, quote too low and the available power looks too low.

So, repeat after me, 3500W is not the power output. The US government is, AFAIK, most interested in actual power output - there are various different definitions there as well (BHP vs. HP, at the crank vs. at the wheel, with accessory load vs. without etc.).

On an XM-3500Li we have a controller that supposedly (yeah, I know!) puts an 80A limit on current output and has an approximately 60V pack. That gives an approximate power output of 4800W. That's a really rough estimate because it's not power measured at the wheel, doesn't include operating efficiency of motor or controller, not accurate measurement of amps or volts etc.

Really, the only point I'm making is that power output is not related to power rating.

So, if you want to look at comparing power you need to know the amperage limit of the controller and the available voltage. From those figures you can estimate power output.

Ignore the power rating of the motor (well, OK, don't ignore it but don't rely on it too much).

Capiche?

:-)

John H. Founder of Current Motor Company - opinions on this site belong to me; not to my employer
Remember: " 'lectric for local. diesel for distance" - JTH, Amp Bros || "No Gas.

davem
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Re: XM-3500- How much HP?- The feds have a statement...

John,

per your
"So, if you want to look at comparing power you need to know the amperage limit of the controller and the available voltage. From those figures you can estimate power output.

Ignore the power rating of the motor (well, OK, don't ignore it but don't rely on it too much)."

---------------------------------------------------------------------
I totally agree, BUT I am NOT talking physics, I'm talking law. As per the fed law they look at the rating of the bicyle MOTOR. No other elaborate tests or expectations noted.

My only point here is that you have legal presednce (in the US) of claiming your "vehicle" is under 5hp by federal guidlines.

I am NOT refering to POWER, Work, Force, F=MA, v=IR or anyother "real world" formulation - just how the federal highway department translates motor ratings in Watts to Hp .

Now, you may say "if the law assumedsthat, the the law is an ass", ...and I would agree :)

jdh2550_1
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Re: XM-3500- How much HP?- The feds have a statement...

Hi Dave,

No, don't worry, even I'm not naive enough to assume the law makes sense... ;-)

However, I think the law governing motor vehicles with VINs (not e-bikes) is interested in BHP which is Brake Horse Power, which I think is defined as power at the crank with no accessory load.

I think "power at the crank" is equal to "power at the wheel" for a hub motor with no gearing...

If that's true then the best way to find the BHP for an XM-3500 would be to simply put the bike on a dyno. Anyone have access to a dyno? I'll ask around and see if I can get some "free" time on a dyno somewhere around here (within a 20 mile radius of course! ;-) )

John H. Founder of Current Motor Company - opinions on this site belong to me; not to my employer
Remember: " 'lectric for local. diesel for distance" - JTH, Amp Bros || "No Gas.

Mikie
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Re: XM-3500

Submitted by sparc5 on Tue, 08/12/2008 - 06:19.

Can anyone tell me what the max output of the XM-3500li charger is? I hope to have the prototype XM-3500li BMS ready by week's end.

Hey Sparky I been wondering where you been the last few days, its been awfully quiet your direction....mad scientisting huh? Well it is good news that you believe you are on the scent of a BMS for us. That should give us that 5-10% extra charge that we cannot get without the BMS and also be sweetness on getting 4-7 years out of the battery pack? Sign me up for one of them(of course once I get my paid scooter{of all of us I should be the one bitching the most about not getting what I already PAID for}).However we are going to have to ask John or Henry if they are willing to be the guinea pigs for Sparkies X? 3500 BMS!

ps I am not complaining about the Chinese, it is nothing I would not expect from a new tech and from them, just please give us plenty of parts eg more battery packs etc and lets SUP UP these babies and head out on the freeway, (yes I know we will need to increase the hub Wattage from 3500 to at least say 4800? sorry irony is just so easy to slip out from reading all these banterings) M

mikie

TANWare
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Re: XM-3500

Hi using the formula found here http://gtechprosupport.com/support/AeroDragCalc.htm and assuming 2x4 frontal area at 0.5 cd for 55 mph

0.5x8x55(cubed)
------------
150,000

is 4.43 HP. Since these bikes were tested at 63 mph equivelant and 10% inaccuracy we are just about right there.

Now 60mph needs 5.76HP or now I guess a 4500 watt hub motor.

Now 75mph 11.25 HP or a 8500 watt hub motor.
Again though this is all speculation.

Mikie
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Re: XM-3500

Hey Guys-- When I am going downhill(Seattle has steep ones) on my Kasea 2000 and I can actually hit 40-45mph I find that is way fast enough on that small scooter. The X?3500 is actually less weight than my 2000 and just a little bit larger, I am going to be very cautious going that fast or faster on such a lightweight bike. The ICE's have the advantage of weight and sturdy design to keep their bikes safe and stable. Getting blown by, by a semi at even 50mph or hitting a pothole are just two examples of eye awakening experiences on any small to medium ICE motorcycle. Granted we all want to get on the freeway with an electric but safety is and should be of the utmost importance. Mikie

mikie

PJD
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Re: XM-3500

TANware,

It is unlikely that the CD of a motor scooter is as low as 0.5. 0.7 to 0.8 is probably a generous value. Assuming 0.75 seems to work for the observed speed/power output in my e-max.

And Mikie, actually, even with the LiFePO4 battery pack, the XM 3500 is probably a bit heavier than a gas version of the same scooter.

But all the Chinese scooters have rudimentary, poorly damped suspensions, which for the electrics are made worse by all the unsprung weight of that 40 lb. hub motor. My rear wheel bounces like a basketball on washboard surfaces. Hub motors are wonderful in their simplicity and reliability, but it will be hard to make them safe at highway speeds. I'm sure that's why the Vectrix doesn't use a hub motor.

Henry42
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Re: XM-3500

The max output of the charger according to the label on the charger is 72.6 volts

I finally got it out on the road. Here is what I found after 20 miles, the volt gauge still was on “H” All the cells were 3.24 volts except one, which was 3.17 V.

I found a potentially hazardous issue. The positive lead of the charging cable is directly under the bolt that attaches the storage compartment to the frame. I think after a while the insulation will wear and cause a direct short of the most positive battery to ground (all 60 volts) If the connector had been mounted 0.5 inches to either side it would not be an issue. I wrapped some electrical tape around it for now.
DSCF1445.jpg

I had someone follow me in a car and what I found was (scooter versus car) 10 mph was 10 mph, 20 mph was 20 mph, 30 mph was 30 mph, 40 mph was 35 mph, and 50 mph was 42 mph. I had the throttle wide open and could not go over 50 mph (42 mph by the car), and this was on a relatively flat road. I weight 180 pounds. I did notice that the scooter accelerated well up the hill. (The one that elevated 70 feet in about 0.2 miles)

I would be happy to be a guinea pig for the BMS (with certain precautions). I took the advice of PJD and installed two 12-connector barrier strips to test the voltages. It makes checking the voltages much easier. (Thanks PJD for the suggestion.)
DSCF1448.jpg

PetroZero
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Re: XM-3500

I had someone follow me in a car and what I found was (scooter versus car) 10 mph was 10 mph, 20 mph was 20 mph, 30 mph was 30 mph, 40 mph was 35 mph, and 50 mph was 42 mph. I had the throttle wide open and could not go over 50 mph (42 mph by the car), and this was on a relatively flat road. I weight 180 pounds. I did notice that the scooter accelerated well up the hill. (The one that elevated 70 feet in about 0.2 miles)

Thanks Henry! This is exactly what I was looking for in terms of actual speed (and more). You've managed in a few words, to clearly convey the actual real world speed in relatable terms.

Something is amiss though, your findings put the top speed at 13 mph less than the advertised "tested" top speed of 55 MPH. Perhaps you've got a problem with your bike? Or was the advertised top speed grossly innacurate?

~ scott
My Blog: <a href="http://www.petrozero.org">PetroZero.org</a>
My Bike: 2007 Lashout Electric Scooter (12mph/12miles)
Considering: xm-3500Li

davem
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Re: XM-3500

The max output of the charger according to the label on the charger is 72.6 volts

I had someone follow me in a car and what I found was (scooter versus car) 10 mph was 10 mph, 20 mph was 20 mph, 30 mph was 30 mph, 40 mph was 35 mph, and 50 mph was 42 mph. I had the throttle wide open and could not go over 50 mph (42 mph by the car), and this was on a relatively flat road. I weight 180 pounds. I did notice that the scooter accelerated well up the hill. (The one that elevated 70 feet in about 0.2 miles)

Thanks Henry. There seems to be a pretty wide spread of max speed in the 3500 that can not be accounted for by the rider size or terrain.

While that interest (disturbs) me, I am really interested in the torque/hill climbing capabilities. When you hit this hill how fast were you going , were you able to maintain that speed , and do you think the bike could have handled that "indefinitely" ?

dshupp
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Re: XM-3500

Wow -- if that is the real top speed, that is disappointing. With the larger motor and lighter batteries, I expected the performance claims to be true and this bike would perform more like a Vectrix. If 42mph is the actual top speed, it is not any faster than the XM-3000.

David

Henry42
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Re: XM-3500

Two FYIs:
The yellow button (which sounds the horn) is suppose to be the starter button for gas scooters.
The windshield that I thought was opaque is really just very dark (The kind of dark that would be used for arc welding. Please don't use for arc welding, I sure it is not certified for that.) I discovered that as I was looking toward the sun.

After a total of 58 miles (I think I charged it after somewhere between 8 and 20 miles. Sorry I wasn't attentive at that point, I'm logging it now.), I needed to recharge the battery. I noticed that the gauge went from H (meaning full) to the half way mark in about 100 feet (going up a hill). I thought it was strange so I decided to check the batteries (Once again thanks PJD for the tip to get a connector.) I found that all the batteries had around 3.2 volts except one (#11 using my number pattern) which has 1.3 volts. Yesterday all the batteries had 3.3 volts except one (the same one that had 2.8 volts. I have ridden 5 miles today. It might be that the low speed was due to a bad battery. I completed a ticket with Xtreme. I will let you know what they say.

I sent a request to Thunder Sky for the owners manual (Since the charger manual is for a YMC charger) This is the response I received:
my name is Marco Loglio and i am the vice president of Thunder Sky lithium battery . I would like to make clear that the motorcycle you bought has noting to share with our production. Actualy the battery are made in another company ( thunder sky Ningbo, and the charger is not madeor approved by us).
We can warn you that we received several complain about this charger and we have been even inform about some accident because the defective charger.
Actualy a charger for lithium battery should be provided with a temperature sensor to avoid the heating during the recharging time.
Also need a BMS to keep the balancing in the cells.
We, have already in the market a similar motorcycle with all the safety items including special charger with themperature sensor, BMS with screen on the dashboard, interacting with the charger and the controller to give longer life and safety to the battery pack.
You can get more informations on our original products on our web site: www.thunder-sky.com
Please feel free to contact with us for any further informations
Dr. Marco Loglio

HalfMooner
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Re: XM-3500

Thanks again, Henry, for your reports. That reply from Thunder Sky is a shocker, to put it mildly!

Mikie
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Re: XM-3500

Henry--You are going to get alot of goodies from Santa this year for being so damn good! Oh My God
this battery thing is taking on the aspects of a bad horror movie....M
Sparkie where are you? There's more good info on the BMS to piece together....

mikie

Mikie
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Re: XM-3500

Hey Kids: I did some detective work on Google, I entered: thunder sky ningbo Lookie here!
the plot thickens....

http://elitepowersolutions.com/products/product_info.php?cPath=1_4&products_id=35

mikie

PJD
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Re: XM-3500

That IS a shocker! - The cells have the blue and red Thundersky globe/lightning bolt logo, correct? This is supposed to be their registered trademark and these "Thunder-sky Ningbo" cells are counterfeits - they copy their logo, and even their their slogan "one percent progress every day"

Here is the real Thundersky:

http://www.thunder-sky.com/

Here is the counterfeit:

http://www.thunder-sky.cn/

The real Thundersky has been in business since at least the 1990s, Ningbo has been in business since only last year.

And I was very close to buying some spare cells from a US dealer called "elite Power Solutions" which I now recall called their cells "Thundersky ningbo"

Every time I think I've plumbed the depths of unethical behavior on the part of Chinese businesses, something like this come along.

Of course, that cell at 1.3 volts is ruined. Even one excursion below about 2.1 volts - under load, ruins any LiFePO4 battery.

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