Bulging batteries

[OldNick]

I have maybe 1/2 dozen LiPo batterties. Two of them have bulged. Neither of them has had hard use or charging. They have both sat for maybe 3-4 months unused innside the house at a max temp of 30-32 C. Same as the others. But they have bulged. One is a Turnigy and the other is a Chinese-bought no-name. The TG has bulged maybe 2-3mm of soft gas and the other about 1mm.

So why are they bulging, and should I dump these?

Thanks for any help.

Nick

 

[SilverFox]

Hello Nick,

When they bulge it indicates that damaged has occurred internally. One cause of this can be rough handling. I know of one case where someone ran their fingernail across the cell (not very hard but enough to make a small crease) and it bulged. Note that this damage can happen before you take possession of the battery.

The bulge is due to a build up of gas inside the cell. Some have given the cell a pin prick to release the gas then sealed up the hole but if you push the pin too far in you can short out the cell and have a much better problem on your hands. This is not recommended. Not at all.

If you keep close track of your batteries performance you will notice a fall off when the cells start to bulge.

The safest thing to do is to properly dispose of the battery.

Tom

 

[OldNick]

Thanks for that. Boy these batteries are a bit drama queen aren't they? I have certainly not done anything to either of these. I did badly under discharge another one, though and it's fine!

Shrug