Saint-v

Ok this just happened to me last night. I have 2 six cell packs of matched IB 4200. they are about 3 moths old and have less than 50 charges on them. anyways, the last couple of times i charged them i had noticed one of the packs was getting a little hotter then the other one. Well i was charging the pack that gets hot last night while me and my brother were watching TV. Well we are sitting there and i keep hearing this pssssst pssssst pssssssst. and i kept asking him if he heard it and he didnt well, i just figured my mom was boiling water to cook with or something. well i get up and i notice the boiling sound is coming from my battery pack while it was on the charger!!!!!!

I figured it was going to vent or whatever ad leak acid out so i carried it outside and put it in the middle of the driveway. I was pissed too cause they were new and definatly not abused and I use a very good charger and built them perfectly. Anyways after i put the pack outside i came back in and just as i sat back down to watch tv, me and my brotehr both hear this BANG!! not like a poof but like a gun or something. i go wasnt sure what the hell it was but went out side and sure enough my battery pack was blown to peices. it wasn't a little explosion either, it was like a dam bomb went off. all teh connectors got blown off. the cells were split apart,a nd the one cell that was making the sizzling sound was completly gone, there was absolutlely nothing left of it like it had been vaporized. there was all these black pieces of shrinkwrap shrapnel laying around but i never actually found the metal casing of the cell.

I am just glad i took the battery pack outside when i did, it could have been a disaster if this lil bomb went off in my house with people around it. I wish i would have had the idea to take a picture of the aftermath this morning when i went outside to see exactly what happened. but yeah be careful with these things and dont charge them unattended and ESPECIALLY NOT AROUND PEOPLE!!!

I didnt know Ni-mh could violently explode like thisi thought they were completely safe!! I guess if im going to have exploding batteries i might as well buy some Lipos

lee172

sounds nasty, do you have any pics of the aftermath?

Saint-v

I know...... just as i finished sweeping up all of the shrapnel and crap that was left over from the explosion, i was wishing i had taken a picture. I threw away 2 of the batteries that were completely separated from the pack, and the one cell that exploded is completely gone but ii did save the other batteries so i can get a picture of those. just imagine a trashed looking battery pack with the shrink wrap melted off. oh i can take a picture of the big black spot it left on the drive way haha

cornel4web

my friend happends the same...one cell explode into a 6 cell from hot bodies...stock battery from a savage truck...and the boom was inside of an c klasse merc...[:-][:-][:-]

I think, if the battery are completly depleted, one cell is changing polarity...and then disaster stroke...hmmm I was think the lipo is the dangerous one...[:-][:-][:-]

Yub, yub, cmdr!

[:@] I buy EP4200 now...

J-Cube

Wow. No explosions here so far. I once had an NiMH pack melt (fall apart) on me but thankfully, there was no fire or explosion. Just out of curiosity, what charger were you using? How many amps were you charging the batteries on? You said they've gotten hot before, how hot? Let me know some more so I can determine the cause of the explosion and how to avoid doing it myself.

skidooguymxz550

wow!!! i had the same issue in a boat. probally 25 runs on a 6 cell wcib 4200. i was driving it by the dock and out of nowere there was a boom like a shotgun. only one cell blew but the whole but was cover in stinging black powder and this screen door like material.

it blew my motor off it's mount put a hole in the freeboard and put hair line cracks all over the gelcoat.

i got pictures and a video of it but when i load the pics onto the harddrive it doesn't recognize the last 50 pics

Saint-v

well, all i can say is that the last few times i pulled it off the charger, the battery was warmer than it should have been, actually pretty hot.

I charge them @ 4 amps, and i use a Tekin bc112 charger

Saint-v

wow, thats sucks it damaged ur boat. but yea i had the same black screen door stuff all over the place when my pack went boom. kinda like black cloth stuff

skidooguymxz550

i though i was just pulling to many amps but hearing that one blew up on the charger worrys me. the only batts i have are ib4200's

the funny thing is i had the boat cleaned and running three hours latter.
i found my metal casing. it was lodged in the foam flotation in the front. looked like a spent shotgun shell. ripped the pack apart

MonkeyFist

I see this alot, people are miss informed about the dangers of NiMh batteries. I see people talking about LiPo saftey all the time, but they forget that a NiMh cell is actually more dangerous. A LiPo cell is dangeropus because of the flames they produce during a failuer event, but the packaging of a LiPo pack actually keep it from having a violent explosion. This is because the packs are bacically foil wraped, and woun't hold that much pressure. A NiMh cell is usually made with a steel shell, which can contain much higher pressures. If you have a NiMh failure event the chances of a violent explosion are much higher than with a LiPo cell. The flames from a LiPo cell are hotter, but the lack of flying steel shrapnel actaully make them a bit safer. Over in the RCtech forums there were pictures of bits of a NiMh canister embedded into a concrete wall. If you want the safest non babysitting style charger, you need to have one that will monitor pack temps and kill the charge.

hands without shadows

You say you built the packs yourself, was it your first time? Im betting you damaged the seal in the cell that blew up.

Btw, the psssst is the cell venting.

speedyAK

Dang Saint-v, you got pretty lucky there.
Last night, I charged my Top Qualifier 4.4k sxs pack at 3 amps, and put it in my rustler. When I applied some throttle to test it, the connecter from the ESC to the reciever started smoking and I quickly unplugged the battery. The bottom half of my reciever case was melted and one of those pins that hold the futaba connecter on was pulled out when I disconnected my ESC from the reciever. I have a Novak smart discharger for my sxs packs and when i went to discharge the rest of my unspent charge in my battery, the cells were starting to smoke and my battery was really hot. I knew that my batteries were spent so I just throught them away. They had about 20 charges on them, maybe more. I left them in the cold for a while and there was a bit of moisture in the air so that must have ruined the packs. They didn't have any shrink wrap on them or anything. I just used them like they came. I ordered them from maxamps last year and didn't use them much.

I'm planning on getting another TQ reciever and a servo for my rustler and some tenergy 3800 batts to try them out.

J-Cube

After reading all this, I got to say, I'm going LiPo. For safety of course.

Takedown

My Feedback: (23)

If you guys think lipo battery dangers are the same as nimh/nicd battery dangers there not even close. Its like comparing a firecracker to a grenade. One shoots flames and blows up while the other just blows up with less force.
Heres proof.
Lipo battery explosion- http://youtube.com/watch?v=KpUXuEg3fNE
Nimh battery explosion- couldnt find one...

Here the aftermath of both explosions.

Nimh explosion


Lipo explosion


I personally dont think the damage/aftermath is even close.

Saint-v

its possible i damaged the batteries when i built them but not very likely. I've been building my packs for the last 5 years, never had a problem until this one......

This is what i think happened. I built two of these packs and me and my brother both share them. well he broke his xxxt so he was running one of the battery packs in my xxx buggy, i was out watching and he ran it down only to about 1/2 of batteries charge before he put it away. well my brother is rather careless and he didnt turn off the ESC When he put it away. I know this because I went to go drive car and i saw that the switch was still on. I thought something was wrong with the ESC at first because there was absolutley no juice getting to it, not even enought o light up the ESC's LED light, but then it clicked that my brother was the last to drive it. So what i think happened is when it was left on it got wayyyy over discharged and one of teh cells reversed polarity cause i was able to charge it a few times after that(this is when it got hot) and then it went boom

paintstikker

The black stuff with the holes is metal; it is the screen with usually round holes that is a tube inside the battery.

Probedude

Probably too late, but don't get the Tenergy 3800's. I bought a pair of them, after 6 cycles the best they would do is 2900mAH and that's at 1C discharge rate. I've since put 20 cycles on them and the capacity has dropped to 2800mAH.

They ignore emails and won't replace them either.

Dave

x2o

try talking to TenergyRep on this forum, he'll point you in the right direction.

Almighty ODST

TenergyRep doesn't work at Tenergy anymore...he said the job of pushing papers around about batteries wasn't him so he went back to being some sort of engineer.

maxxdout

I remember one time when i was charging a dynamite 1500 pack for my emaxx,i saw it lighting up inside so i stoped charging it and it never exploded. i jus through it in my garbage can(outside) and forgot about it. ALso, my heli lipo was growing one time and it was really wierd. it would puff up and stuff. thats it the garbage too.

rs670

My Feedback: (1)

Here's a picture of a 4200 Ni-MH 1.2V single cell made by Intellect. After soldering the connector, I put it on my E-Station BC-6 charger for the initial charge. I set it to charge at .8A for 440 minutes. (Just over 7 hrs)

After approximately 4 hours it exploded. There wasn't much left to look at other than the hole in the wall. I'm glad I wasn't in the shop at the time. It literally exploded like a grenade.

I emailed Intellect asking what I did wrong but NO REPLY!

aftermarket

My Feedback: (2)

Alot of people miss this: on the battery packaging or sometimes on the batteries, it'll say, do not trickle charge. I saw that and I got lucky. If I peak my battery (it goes into trickle after it peaks) and I leave it on the charger, it gets hotter than if I just got done driving w/ em, cuz venom bats don't allow trickle charging, if that's the case w/ ur batteries (sorta sounds like it...idk) I'd peak em and take em off immediately. Good luck w/ ur future batteries and stay safe! I'm glad you took ur batteries out in time

bandit racer

my battery exploded after driving it, does that happen often?

john01374

If you are referring to NiMh packs then yes. It happens a lot more than people want to talk about. For years all we've heard is how dangerous LiPo packs are but no one wants to talk about NiCd and NiMh.

In all my years in this hobby I have had tow issues with LiPo but I've had a dozen or more LiMh packs catch fire or explode sending cells flying across the room.