Bloated Lipos

[PMX13]

Hello,

A couple of my batteries get 'puffy' or bloated after long runs. It's as though they've been inflated with air, with about 1/8" to 1/4" of air space between the batteries and the outer skin.

They aren't getting real hot, maybe 120-130F.

Venom 5400 2s2p 7.4v

Dangerous?

[Jay Turner]

Do they go back down after they cool off? What "C" rating are they? Several of us had 2S ThunderPower packs do the same thing a few years ago, no problems as they deflated when cool. The Venom packs may be from the same vintage. Watch them but if they deflate you are probably fine.



.

[Dwyer]

Depends on if it's the cells or the shrink that is puffing due to pressure build up. If it's the shrink it will pretty much stay puffed once it cools off. If the lipos' stay firm on the sides and after things cool off and you can push for a bit and then it gets firm then it's the shrink that puffed from the air pressure caused by the heat.

[PMX13]

Thanks for the replies.

They do go down when they cool. So I won't stress about it.

I think it started happening after removing some velcro that was glued to the skins.

(They are 20C btw)

Thanks again!