NiMH Battery "self-combustion" query

ambro25

A battery I recently sold was allegedly received "hot to the touch and melted around the bottom battery" (that's all the info I have at the time of this post).

Now, this battery was placed in a standard paper/cardboard packaging, not connected to anything whatsoever, and in perfect condition. The connector and short wire were secured against the battery pack by a small rubber band, to make sure they wouldn't flay about in the packaging.

It's a standard Firefox 8.4v 1500 mAH, which I had used in my DBoys M4A1 and SIG 552 with no issues whatsoever, and which was last charged and used at the HRTA Birthday shoot, again with no issues whatsoever.

In all, it's probably had 9 charges maximum (the number of times I've been to HRTA, so the regulars will have an idea) and always using a DLP charger, btw.

Can I ask for thoughts, as to what could possibly have happened?

Anyone heard of such "spontaneous heating" issues for NiMH batteries?

ED E

The "tamiya"(?) connector, was it in any way damaged? It mush have shorted so the only thing I can think of is if the connector was damaged and the pins touched...or if a cell ruptured:rolleyes:

ambro25

The battery pack was not damaged in any way, nor the short cable length, nor the mini (Tamyia) connector.

Unless it got damaged in transit

How hard would it have to be knocked about, to cause the kind of damage you suggest ?

ED E

ambro25 wrote: »

The battery pack was not damaged in any way, nor the short cable length, nor the mini (Tamyia) connector.

Unless it got damaged in transit

How hard would it have to be knocked about, to cause the kind of damage you suggest ?

The tamiya would have to be smashed so the contacts met. Otherwise its in the actual pack. Option 1= Stabbing them. Option 2: Dropped significantly causing a cell to burst and shortin the current. Could just be a leak(Ever had white powder in the batt compartment of a remote or somtheing when you went to change the batteries?) but that shouldn't happen with new batteries. What state was the package in?


PS: This is my "novice" opinion. Dex is the man for electronics round here.

ED E

Dad just mentioed something, could well be the cause; Moisture. Postman out in the rain. If it did get wet, or even damp that could cause it.

johnboyire

the envelope was not wet just hot from the battery when it arrived the plugs appear fine

but as you can see im not to keen to put this near an aeg

ED E

Any kind of residue?

johnboyire

none except for looks like condensation near the end on one side but its on the inside of the plastic

ED E

I'm not sure what caused it but one thing I do know, its royally screwed. Bin it, actually, recycle it.:D

PS: WTF is up with boards tonight, lots of 404s

Masada

if the envelope was hot when ya got it then the damage must have happened fairly shortly before the post man arrived with it and was probably in perfect condition when ambro sent it, id say get in touch with an post about claiming them for damaging it maybe.., ive had some packages come im that looked like a dog chewed it or something., there not exactly careful with them.,:(

johnboyire

whatever happend to it its done for thanks all