Inmotion V13 Speculation

[HEC]

45 minutes ago, Josiah said:

voltage going all over the place in real time.  I’ll keep it in the fire pit for now. 

Those changes are fairly quick for the actual two sets of cells (there are more than one in each monitored group, 4 I think in this case) to actually charge and discharge that fast. Not technically impossible but less likely I'd say. I'm more inclined to believe it's down to loose solder / weld point. Either the one used by BMS to measure the voltage at the point between those two sets, or the actual connection between them. If the latter, increased resistance and possibly even intermittent break in the connection might correlate with the behaviour you've described so far. Either way, as battery packs are sealed tight, I don't think you'll able to avoid replacing the "funny" one (or perhaps even the whole wheel) ...

Edited March 5, 2023 by HEC

[HEC]

42 minutes ago, Tawpie said:

Take the bad pack off, if it goes up in flames your entire wheel doesn't have to be toast too. Although, this wheel has had enough quirks a full replacement might be just fine too!

19 minutes ago, Josiah said:

Maybe I wait to see what Jason wants me to do first.  I think I can manage that if he gives me the go ahead. 

If nothing else I'd probably at least try to unplug both packs, so no voltage is being drawn from the faulty one or "balanced" between both packs.

Edited March 5, 2023 by HEC

[Josiah]

Is there a short cut to unplug the packs or do you need to slide out the whole motor first?

[chanman]

If the readings are all over the place most likely the problem is not in the actual cells but in the sensing. One of the downsides of the smart BMS I guess, if the sensing isn't completely reliable you get the possibility for something like this. 

I also have the impression 5.1V isn't a real possible reading for a lithium ion cell, more than 4.3-4.4V it starts to break down.

Edited March 5, 2023 by chanman

[HEC]

1 minute ago, Josiah said:

Is there a short cut to unplug the packs or do you need to slide out the whole motor first?

I think you might be able to unplug at least two plugs from the tail light board without any disassembly simply by reaching into the gap above inner fender.

[Punxatawneyjoe]

1 hour ago, Josiah said:

Kids added water to the mix for further precautions.

lol, great back yard. Sucks to see it sitting there but you can't be too sure. I think @Tawpieis right. I would ask for a replacement pack. They should ship one out right away. I'm sure they would rather get yours back and check it than have a fire on their record. No cheating either, you have to get you honey from the supermarket like most everyone else...

I do feel like it's more of a sensor problem though since the voltage is all over the place. Also one should never have been allowed to get to 5.1v so it must have happened instantaneously. OFC i'm no battery expert.

[Punxatawneyjoe]

21 minutes ago, Josiah said:

Is there a short cut to unplug the packs or do you need to slide out the whole motor first?

pull the rear bar then the handle and top cover and you can just unplug them, they are right on top, don't forget the screws under the rubber shock plugs but don't touch the shock rods just the 4 Phillips head screws. There is also one on the side under a sticker.

Edited March 5, 2023 by Punxatawneyjoe

[HEC]

45 minutes ago, chanman said:

I also have the impression 5.1V isn't a real possible reading for a lithium ion cell, more than 4.3-4.4V it starts to break down.

 

26 minutes ago, Punxatawneyjoe said:

I do feel like it's more of a sensor problem though since the voltage is all over the place. Also one should never have been allowed to get to 5.1v so it must have happened instantaneously.

Agreed. I've suspected / mentioned here the possible issue with BMS or wiring right away after @Josiah posted the first time about this, and as more details unravel, it looks more likely. 

And, if that's the case, the likelihood or fire or any other "destructive" behaviour is much less likely. It's still best to not attempt to charge or use wheel any further though. Also, discuss with eWheels how to secure the wheel or faulty pack to safe shipping back.

Edited March 5, 2023 by HEC

[Cerbera]

47 minutes ago, HEC said:

Agreed. I've suspected / mentioned here the possible issue with BMS or wiring right away after @Josiah posted the first time about this, and as more details unravel, it looks more likely. 

So even a machine as well built as the V13 isn't immune to problems then... seems there are small patches of shade on the sunny side of the street ! :/

[HEC]

6 minutes ago, Cerbera said:

So even a machine as well built as the V13 isn't immune to problems then... seems there are small patches of shade on the sunny side of the street ! :/

Hard to avoid on such fairly complex device with multitude of suppliers. Inmotion doesn't manufacture the battery packs themselves (or the bolts for example), the Huizhou Blueway Electronics does as commissioned by Inmotion. Lose or poor quality solder / weld point is pretty tricky to discover without some really advanced diagnostic equipment, and even then it might not demonstrate until after shipping and or some initial use, where the vibrations will contribute to the future developing of the fault. Something like impurity in the soldering flux or some grease residue on soldering or welding point is all what's needed to cause this, especially in "budget" assembly environment far from perfection of "clean room".

[supercurio]

6 hours ago, Josiah said:

5.1V is dangerous, please don't keep the wheel indoors or in an apartment if you can.

If that measurement is correct if could self ignite any moment.

 

Edit: I caught up with the updates, it looks like the BMS had bad, inconsistent readings indeed, which can lead to making poor decisions in how to drain cells to balance them. Over time it means it could heavily discharge a cell seen as 5.1V and and damage it, which then can become a fire risk in itself (if charged again)

This pack needs replacement and a full investigation, hopefully with a report we get access to for transparency sake.

Edited March 5, 2023 by supercurio

[Josiah]

voltage reading
https://m.youtube.com/shorts/VfzAj91n1cA

Got the wheel near an exterior door, away  from the main living area and three other exits.  Not sure if I want to leave it outside over night.

[Cerbera]

46 minutes ago, Josiah said:

Not sure if I want to leave it outside over night.

I feel the dilemma, but 5.1 is mental high voltage (if it is true info), and the fact that it fluctuates like that is equally concerning. If you don't know if those reading are real or not it's gotta go outside dude. You might be OK if the readings are false, but if not you are in coffin corner with that pack - it is the very holotype proverbial 'accident waiting to happen' so if you don't know, it a risk not worth taking to keep it indoors.

Edited March 6, 2023 by Cerbera

[mrelwood]

5 hours ago, chanman said:

If the readings are all over the place most likely the problem is not in the actual cells but in the sensing.

I agree. It looks like whenever the high cell group gets a higher reading, the low cell next to it gets a lower one. Seems as if the one sensing point intermittently loses one of it’s connections, or has a failing component.

5 hours ago, chanman said:

One of the downsides of the smart BMS I guess

I don’t think so. All EUCs have the same voltage sensing mechanisms for overvoltage recognition, the V13 only lets also the user see the individual voltages. No reason why the same components couldn’t fail in a traditional EUC as well, causing intermittent failures and engaging protection mechanisms.

 

33 minutes ago, Josiah said:

voltage reading
https://m.youtube.com/shorts/VfzAj91n1cA

Yeah, I also think that the change is too fast to be actual battery voltages. But handling the wheel as a fire risk still makes good sense at the moment.

I hope you get the wheel fixed soon!

[Forwardnbak]

just got the call mines ready!

Chuffed.

In next while i’ll meet the wheel. 

 

[Forwardnbak]

hello you

 

[Paul A]

3 hours ago, Josiah said:

Got the wheel near an exterior door, away  from the main living area and three other exits.

 

If the wheel does self immolate, it is explosive.

Positioning it near an exterior door might be futile.

V13 has very large capacity battery.

 

The following occurred today.

 

E-bike battery sparks 5-alarm fire in the Bronx: FDNY

36K views · 6 hours ago...more

PIX11 News

192K

 

 

[2disbetter]

I hope companies are seeing things like the above. The shoddy manufacturing and QA is going to get their products banned. I am happy that Inmotion sees the writing on the wall and is trying to meet the quality requirements these things deserve. 

Regarding Josiah, the only time I've seen this kind of battery im-balancing was because of weather related issues. At cold temperatures cell structures break down. Cold kills lithium batteries. The issue you are seeing could be more than that, but in general never leave your EUC in a space where the temps are at or below freezing. 

That said Chooch has finally gotten the wheel and is, as expected, in love with the thing. Passing traffic on a highway in fact. He mentioned that Inmotion is going to release a software update that will unlock Geek mode, and 60 mph / 100 km/h. 

Edited March 6, 2023 by 2disbetter

[mrelwood]

1 minute ago, 2disbetter said:

He mentioned that Inmotion is going to release a software update that will unlock Geek mode, and 60 mph / 100 km/h. 

There are rumors that it may not be coming after all. If so, my guess is that a certain high speed overlean could’ve been the cause for them backing out.

 But it’s still just a rumor. Let’s wait for official information.

[Paul A]

5 hours ago, Josiah said:

Not sure if I want to leave it outside over night.

 

Spoiler

Could happen when is everyone asleep.

Two EUC fires in Sweden happened at night, destroyed two homes.  Reported by member Mike Sacristan in a YT video, Nov 1, 2021.

An EUC fire in Portland, Oregon, Jan 10, 2021 was at night, when occupants were asleep.

Many others as reported in the fire thread.

 

 

Security cam footage of the Bronx, NYC, supermarket fire, 26 seconds.

 

 

Edited March 6, 2023 by Paul A

[2disbetter]

3 minutes ago, Paul A said:

Could happen when is everyone asleep.

Two EUC fires in Sweden happened at night, destroyed two homes.  Reported by member Mike Sacristan in a YT video, Nov 1, 2021.

An EUC fire in Portland, Oregon, Jan 10, 2021 was at night, when occupants were asleep.

Many others as reported in the fire thread.

They have less capacity and I think they don't output quite as much current but to me switching to lifepo4 batteries would get rid of the fire worries. They will not cause fires. 

Edited March 6, 2023 by 2disbetter

[KiwiMark]

5 minutes ago, 2disbetter said:

They have less capacity and I think they don't output quite as much current but to me switching to lifepo4 batteries would get rid of the fire worries. They will not cause fires. 

You definitely would get less capacity for the same volume/weight. This would definitely be a deal breaker for many riders, with a very noticeable drop in range if they changed battery chemistry. To get the same voltage you would need more cells in series and therefore you would have less cells in parallel on the same size battery - this gives less current handling ability and less capacity.

Just remember, the reported number of fires is a very very small percentage compared to the number of EUCs out there. Similar to the e-bike fires, there are a LOT of e-bikes and a very tiny proportion of them have had the batteries catch fire. Still, it couldn't hurt to store the devices in a location where a fire wouldn't cause a house to burn down, if at all possible. It really isn't going to be practical for everyone though.

[2disbetter]

2 minutes ago, KiwiMark said:

Just remember, the reported number of fires is a very very small percentage compared to the number of EUCs out there. Similar to the e-bike fires, there are a LOT of e-bikes and a very tiny proportion of them have had the batteries catch fire. Still, it couldn't hurt to store the devices in a location where a fire wouldn't cause a house to burn down, if at all possible. It really isn't going to be practical for everyone though.

That is the real issue. Is it easier for people to fire proof store their wheels, or to change battery chemistry? Then again, with the lengths that Inmotion went to with the V13, it might not be necessary to switch. It is just the BMS can't be a shortcut. 

[Forwardnbak]

I had a great first roll. Only 18km but enough to feel it.

FELT IT I DID (the handle kept popping up to say hello and I think wanted to be more than friends!!)

I’m not always that kind of girl on the first date.

Maybe tonight 

[Forwardnbak]

the handle popping up was due to the seat I probably placed slightly wrong (that’s just a bonus tip for anyone wanting more from their wheel)