Major battery melt down

One of IB 4200 eight cell packs melted today. The packs have about ten charge cycles through them. None of the wires melted and weren't even warm.
Appears that two cells actually melted. When I approached the vehicle it was hissing and smoking. Did some damage to my FLM chassis too :031:
Im not sure why this happened. Do these packs just go bad like this?

[Serum]

The main reason why i advice not to use the 4200's...

Sorry to see this happened.

[BrianG]

Yeah, sorry to see that.

It doesn't look like the chassis is bad in any way. Just a matter of a little cleaining.

Why do you advise against using the 4200's Serum? Is it because they don't have as high a discharge current (or "C")? I thought it was just the GP 4300's that weren't as good...

[mwe-maxxowner]

That's why I don't swear by ib like everybody else. Nothing as proven as gp cells. I'll stick with gp no matter what.

[squeeforever]

Well don't go with GP4300's....There not good AT ALL. The IB 3800's are great...

[mwe-maxxowner]

I still love my matched gp3300's I bought nearly 3 years ago. Also enjoy my gp3700s, which are matched as well.

Just ran the truck again with GP 3700's and all is well. Thank goodness the speed control isn't damaged. What are the chances this shorted on the aluminum chassis? Maybe the shrink wrap wore through, i dunno know.

Well, maybe this is an exuse to go LIPO :027:

Anyone want to buy one IB 4200 eight cell pack, like new! :005: :D

[BrianG]

It's hard to say. For the chassis to short out any cells, the shrinkwrap would have to wear in two places. To be safe, I always use adequate (maybe too adequate) padding. It doesn't weigh much and is cheap insurance. I've used firm rubberized weatherstripping (good electrical insulator) and adhesive-backed craft foam. The weatherstripping is a bit thick though, but obviously cushions better. The craft foam I use is 2mm thick, which should be more than enough.

Even so, I don't see any arcing points on the chassis which would indicate shorted cell(s). It could be you were just drawing too much current for too long for those cells to handle and they just heated up too far.

If you go Lipo, make sure you get cells that have a high enough continuous discharge C rating.

[Serum]

Well Brian;

the reason why is because the 4200's have got an exploding nature. It was in the very beginning that Alex from BoomBoomBatts took them of his site, because of this.

[glassdoctor]

Then they sound perfect for "Boomboombatts" hee hee

It's possible they were very mis-matched and two cells were way out of balance... or they shorted...

I've never seen or heard of this happening at the races etc.... everyone running matched 6 cell packs though. (with IB or GP) Only thing I have seen is a pack that makes some sizzling/popping noises while charging.... that's it.

[Serum]

I have got the experience that the IB cells tend to get unbalanced after a while.

[glassdoctor]

I have noticed that my packs appear to "need" the discharge trays more than my old 3300 packs, which would back up what you are saying....

[Dafni]

Originally Posted by Serum

I have got the experience that the IB cells tend to get unbalanced after a while.

Do you mean after a while of sitting or running them?

[Serum]

sitting, while charging them every now and then.

This never happened to my GP's.

[coolhandcountry]

I had good luck with the ib 3800. Ran them for a good bit. I did melt a gp 3300
and a gp 3700. Nothing like that though. I gone lipo now. I don't want no more nimhs.