[WARNING] Gotway Nikola 100v 1800WH Battery Fire

[Murdomeek]

they started using LGM50T cells due to the issue being panasonic 21700a cells they used originally

[alcatraz]

I don't think the panasonic cells are new and that could be the problem. They have uneven wear and might need more balancing than new cells.

It's easier to switch cells than to provide ample and reliable balancing currents, it seems.

[Bacon N Eggs]

On 5/29/2020 at 9:24 PM, Ben Kim said:

the big clue is ewheels fast charger. those have been known to overcharge causing other fire issues (one in nyc) 

Ben

Each cell group in the battery packs has a BMS (Battery Management System) that prevents over charge, over discharge & performs cell balancing. The fast or slow charger cannot cause an over charge condition unless there is a failure somewhere else in the system. 

[RagingGrandpa]

11 hours ago, Bacon N Eggs said:

battery packs has a BMS (Battery Management System) that prevents over charge

True.

But we think the bad thing about the "ewheels fast charger" is its 80% / 90% partial-charge setting. If you leave it set to 80% and use it 20 times, it can result in a badly imbalanced pack, leading to overdischarge of the lowest cells -> cell overheating during riding.

(If you have one of these chargers, I'm jealous! Just leave it on the 100% setting. Or if you're scared, mail it to me, I'll pay shipping.)

Edited September 16, 2020 by RagingGrandpa

[null]

Or, if you have a charger with cutoff, remember to charge to 100% (and eventually with stock charger) every few charges.