Ever Had a Battery Overheat? Share Here

Greetings everyone, I have a question for you: have you had any encounters with the issue of VEX batteries overheating while charging or during use in your VEX experience? I am part of a small research team researching batteries, and while I found a couple threads pertaining to this issue, if anyone has any further anecdotes on the matter we would love to hear them. This can include any type of instance from simply being excessively hot to the touch (emphasis on the word excessively, as all batteries do produce heat while in use) to performance issues or even catastrophic failures. If you don’t necessarily have any anecdotes, we would still be interested in your thoughts pertaining to this issue.

EDIT: Sorry, should have been more specific. The kind of thing we’re looking for is a noticeable drop in battery life in situations such as fast-paced competitions in which batteries are continually charged to keep them at maximum, causing a sustained high temperature. Catastrophic failures would include your more extreme cases such as melting components, fires, or explosions. We know this doesn’t happen too terribly often, we’re just trying to see if we can get a semi-statistical grip on how often issues like these occur as a result of overheating.

1, is this a real person, because these forums occasionally have them
2 if this is a real person, congrats, and yes, when charging on fast mode newer batteries seem to get very hot when at competitions

That seems unnecessarily rude. It’s pretty obvious this is a real person; he/she has been on the forums since last year. Just the fact that there is a location and a team number should be dead giveaways that this is a legitimate post. Please be more cognizant of these things in the future.

sorry, i didnt mean for it to be rude, it just kinda sounds like sompthing a bot would post, im sorry i didnt mean for it to be rude at all

Our Batteries have gotten very hot before but I don’t know what you consider overheated, we used a very sketchy charging station with vex chargers so that didn’t help…

We’ve had battery’s over heat countless time we realozed this so mostly likely because we accidentally as a few of our chargers on fast

Quoted from the big red warning sticker on the chargers:


My batteries don’t overheat. Sure, they get hot, but not excessively or anything.

When your battery is in use, it will produce much power and get heat, it is normal; but when you charge your lipo battery, your battery get hot, you should check your charger (high Current charger will produce heat), you should allow the rule of charge battery. If all ways are right, your battery may short circuit, it is a dangerous signal.

I don’t understand. What is the “rule of charge battery”? And what is a lipo battery?

No idea on “rule of charge battery.”

LiPo batteries are lithium polymer batteries.

We have acually set one of our batteries on fire. The battery was an older one and we believe the main problem was that the charger seemed to be broken and was charging in “fast” mode dispite the switch being in the “safe” position. Not fun.

Somehow managed to leave a battery on fast charging overnight. Was hot the next day and now holds its charge for about 30 seconds

In a community of perhaps 100 batteries, we have had 3 incidents in the last 2 months. Two batteries “exploding” on the charger with one being epic. At least one was an old 2010 battery. We also had a motor controller catch fire during a match with no evidence of any other cause. The motor controller in that case was on a power expander.

I’ve had students accidentally set one of the old smart chargers to “fast” when using the smaller VEX 2000mAh batteries for my PLTW class. I still have the charred remains of the two batteries that caught fire up in my “trophy” case.

Nothing charred here. Had plenty get really hot but nothing catastrophic on the battery end. Plenty of ripped wires because people think the wire is a nice swinging handle. These are expensive items. please treat them with care.

Older ones get very hot. Battery Beak is a nice tool for seeing if a battery is still good enough for competition or needs to be retired for practice use only.

One time a battery over heated the white plastic melted itself on to a power expander.

Why is fast mode even a thing then? I don’t understand.

Mainly for comps when teams are rotating batteries so quickly.

But if it’s told that you should never do it…

Includes fast setting