Has there ever been an Mten3 fire?

[deltaEV]

I'm new to EUCs. I thought I'd done my research and landed on purchasing a Gotway Mten3 so I ordered from ewheels last week.   FedEx is having some sort of delay, so with nothing else to do while waiting for my new wheel, I've been reading the forum and FB gouprs and watching a ridiculous number of YouTube videos about EUCs. Now I've seen enough stuff about Gotway and lithium ion battery fires that I'm freaking out. I've got kids! I can't bring a bomb into my home! 

Has there ever been an mten3 fire? Do I need to be this worried??

[Scottie888]

I haven't seen nor heard of a Mten3 fire & I've cutoff mine & tossed it a number of times. As in anything powered with Li-ion, there's always a possibility of thermal runaways resulting in fires. If you're losing sleep over it, I'd get a fireproof steel safe for charging & storage duties if it were me. IMO the best would be a nuclear proof underground doomsday bunker😁

[meepmeepmayer]

1. Haven't heard of an mten3 fire
2. The latest round of fires seem to be related to the 21700 type of cells used in all the current wheels (in my opinion, at least). The mten3 has 18650 type cells, as were used before. There never were any fire issues with those. The "mass" of EUC fires is a newer phenomenon, and I blame the 21700s.

That's not a guarantee, but I wouldn't specifically be worried about a fire with the mten3.

[Chriull]

39 minutes ago, meepmeepmayer said:

• Haven't heard of an mten3 fire

Didn't some mten3 once have a battery pack internally split in two and just connected with a single nickel strip - which got very hot?

Quote

• The latest round of fires seem to be related to the 21700 type of cells used in all the current wheels (in my opinion, at least). The mten3 has 18650 type cells, as were used before. There never were any fire issues with those. The "mass" of EUC fires is a newer phenomenon, and I blame the 21700s.

+1.

Although some fires seem to be just from low quality battery manufacturing. Like seen in the teardown of a not GW battery pack from aliexpress resellers in a GW wheel (bad welds) which started smoking. And one (some?) more fire of such a modded wherl.

From the reports i saw i'd tend to blame more such badly made mods than gw 21700 cells.

Afair there is not too much heard from KS or Inmotion 21700 cells?

18650 fires were afair just one or two old ninbot one e+. And the very first fire video of one riding in a hallway. And probably some more i forgot again. Would be interesting to make a collection of fire reports!

And not to forget water ingres - seems to be catastrophic for some wheels. Especially with the delay - nothing to notice and then days or weeks later a "spontanous combustion"...

Edit: just found 

 

Edited May 16, 2021 by Chriull

[meepmeepmayer]

24 minutes ago, Chriull said:

Didn't some mten3 once have a battery pack internally split in two and just connected with a single nickel strip - which got very hot?

Yes and no. The too thin strip simply acted like a fuse under high stress. No fire. They put in a better connection from then on, and that was it - mten3 good!

[Tawpie]

I just got mine! If you’re worried, store it in an old barbecue, out of the rain obviously.

While bad things can happen to any battery powered device, the mTen doesn’t have a reputation for problems. I’m not worried at all.

Still, it’s prudent to not charge it (or any device with a large Li Ion battery) unattended. Unless it’s in the BBQ.

[Gasmantle]

The Mten3 has the big advantage that it's relatively small battery charges quickly and shouldn't really need leaving unattended or overnight. I found that with mine a couple of hours was usually enough.

 

[deltaEV]

Thanks for the replies and extra info. It helps calm my fears. 

We got an electric car (Chevy Bolt) last year and when we were hooking up the L2 charger in the garage, we found out there was a problem with our fuse box and it had been arcing in the wall for months. We fixed it but the idea that we had been so close to a housefire was pretty terrifying. Of course, then within a few months, the reports of Bolts bursting into flames came out... fortunately, those also seem rare and there's a software fix until they figure out what's going on there. We keep it outside the garage regardless...

[Killface]

I am visiting the inlaws with an Mten3 and had been charging it outside because all the talk of fires had me super nervous. Probably not needed but you know. Unfortunately the tubless tire lost air and doesn't seem to hold air when i inflate it so not sure what I am going to do about that. 

 

[RagingGrandpa]

On 5/15/2021 at 11:16 PM, deltaEV said:

Has there ever been an mten3 fire?

Yes.

On 5/15/2021 at 11:16 PM, deltaEV said:

Do I need to be this worried?

No.

[.....]

1 hour ago, RagingGrandpa said:

Yes.

No.

The mten is a nice little battery pack mounted in a good spot. Its not much power (comparatively) to have to charge, so you can use low amps and it wont take long. At least my 67v mtens are just dead simple and solid format. The less in it, the less to go wrong. I'd say the chance of an mten fire is VERY low.

@Gasmantle also nailed it. I let mine cool from charge before ride and cool from ride before charge. Probably no need to, but it charges so fast, it doesnt take much planning.

@Killface Not much to think about. Find the leak by inflating and spray with dish soap. If its in the tire, its either replace or repair. Probably be iffy to patch an mten tire tho, they suffer a LOT of deflection in use. Some people like to use slime, so thats also an option. Check the valve and core too.  Using a tube is not a good option. I've a vid of my mten tire swap. It doenst take much for tools at all.

Edited May 20, 2021 by ShanesPlanet

[Chriull]

On 5/16/2021 at 5:16 AM, deltaEV said:

Has there ever been an mten3 fire? Do I need to be this worried??

Seems it just happened

 

 

Edited May 20, 2021 by Chriull

[GothamMike]

14 hours ago, RagingGrandpa said:

Yes.

No.

Yesterday. Gotway has issues. They may want to ensure their supply chain is sending them real batteries and not counterfeits. 

[.....]

I've got a spare mten I could sell for about $1500. Why so much? Because it takes charge and hasnt caught fire...  Quickly becoming more and more rare it seems..

[deltaEV]

Well, I *was* feeling better. Frick. I just spent a bunch of money on that thing...

[.....]

21 minutes ago, deltaEV said:

Well, I *was* feeling better. Frick. I just spent a bunch of money on that thing...

I wouldnt worry too much about it. Maybe turn it on and charge it outside for the FIRST charge. I'd still say this is a low failure rate. However, the damages for a low failure rate can be high. You're in North Carolina at least, we do have plenty of water

A bunch of money is when you watch the new BIG gotway wheels go up in smoke. Some of those cost more than my cars...

Edited May 21, 2021 by ShanesPlanet

[GoGeorgeGo]

Anecdotally, it seems to me fires occur in 3 situations.

1) new wheels defective essentially from the factory. They dont last long before something goes wrong, often times within the first day of ownership it seems. First time its plugged in or ridden it can present an issue

2) when charging. Whether the cells get over volted, or they where so severely under volted that charging got to hot and causes a fire. Monitoring your chargers and batteries regularly should theoretically prevent this from happening to you unexpectedly as you will know immediately your batteries a off, or your charger is mis tuned.

3) while riding. Lose connections happen on drops and bumps, overheating causes a short, something goes haywire while its in operation and causes a thermal runaway to occur. These seem to be the most common as you often hear ," after dropping a small curb" or "going uphill", or "after a crash"

My advice, be very cautious the first couple days you get the wheel. Keep a close eye for abnormal activity, monitor.the voltage of the battery and charger. Take it for a good ride or 3. Once your sure there is no factory defects, simply keeping an eye on the voltage routinely should be safe enough. Just make sure to use the factory supplied charger and routinely balance your battery cells to a full voltage. If it goes up whike your riding at least the chances of it doing any major damage are low (unless your out in the woods , knock on wood thank god no one has started a forest fire .. yet) 

[meepmeepmayer]

@GoGeorgeGo I see it like that - dangers are:

• Defective from factory right away (bad weld or some other electrical connection somewhere)
• Water intrusion leads to a fire directly, or water damage (rust etc.) causes damage (worsening some electrical connection) that leads to a fire later
• Serious mechanical impact
• (Some cell types just seem to be susceptible... or not, I don't know)

I don't think charging itself is a problem. The charging current is below what even the standard charging rate is for the battery cells. They shouldn't get hot at all (discharge when riding is higher, and the batteries don't go up in flames mid-ride). What can happen though is bad electrical connections (welds) from the factory or due to damage over time (maybe from water) getting hot and thus causing the fire.

Also I think fires from a dead wheel (= a short) after a curb... are these really common? Not sure.

This is just my speculation.

-

Be careful and observant with new wheels, and any time a wheel shows unexplainable or inconsistent behavior. But once the wheel hasn't caught fire in the first month, I think it is very unlikely to catch fire later without some extra cause.

Edited May 21, 2021 by meepmeepmayer

[Gasmantle]

Clearly these batteries do have potential risks but that risk is minimal and it shouldn't deter anyone from buying a wheel if a bit of common sense is used.

Provided you don't go out and leave the wheel on charge unattended for hours then you aren't going to have much trouble. Sure the wheel could still suffer damage but that risk is small and you will notice a problem before a serious fire risk occurs.

In over 3000 miles of riding I've no idea how many charging cycles I've done but I never leave the wheel unattended while charging - I don't need to sit in the same room watching it charge but I do make sure I'm nearby / in the next room etc.

[Camenbert]

3 hours ago, meepmeepmayer said:

I don't think charging itself is a problem.

On the case of that brand new, 0 km, Mten ending in flame while charging yesterday, I'm wonder if the charger (new as well, so untested) is innocent.
But then the bms?!
 

[RagingGrandpa]

23 minutes ago, Camenbert said:

Mten ending in flame while charging yesterday

Please let's discuss specifics on that in its thread:
https://forum.electricunicycle.org/topic/23245-brand-new-mten3-charging-first-time-in-my-house-started-smoking-burst-into-flames/
 

22 hours ago, conecones said:

The OP could not get the unit to self-balance upon taking it out of the box and turning it on. After sending a video of the issue to EUCO, they advised that there is no transportation lock on the MTEN3 and instead to charge it as the battery indicator looked low. After about 3 hrs on the charger, it exploded. The OP did connect the wheel to an APP prior to charging but does not recall the voltage reading.