LiPo puffing?...hard or soft?...HELP!

[jsr]

A couple of my LiPos look to have puffed. It didn't happen while in use. It actually happened when they were sitting for a couple of weeks. I've had 1 LiPo puff before and it was hard, meaning I couldn't squeeze it, it didn't have much, if any, give.
These 2 packs that look a bit puffy now are soft and easily squeezable. They give easily and bounce back to a slight puff. It looks like just air in there.
When LiPos puff, are they supposed to be hard and unsqueezable with no give? Or are they soft, squuzable, with give and bounce back?
Just trying to check if the 2 LiPos I have now are actually puffing or perhaps just the hot weather we've had lately.

Thanks.

[emaxxnitro]

they are good. lower quality lipos tend to get mushy after a few uses, my turnagys got mushy but its not a puff

[The Dan]

My Venom X-Packs (5000mAh, 20C 2S) puffed a while back after a little too much run time. They came out of the buggy at 135dF with a few millimeters of puff each, and they were soft at that point. However, after recharging them, the puff went down, and now they are -mostly- hard.

I also have a pair of SMC packs (6000mAh, 28C 2S) that will puff if pushed below 7.8v (approximately). They are slightly soft when they are puffed up as well. Again, when I recharge them, they go down but not completely flat.

[bryan]

No worries mate you will always get minimal expansion w/heat. Just make sure they dont get too hot

[jsr]

Thanks guys. Yeah, the weird thing is they didn't get hot during use and didn't puff afterwards. They puffed after sitting around with no use. However, they were sitting in sunlight, so quite a bit of heat since it easily hits 95F+ here. I've even recharged them and they haven't gotten hard or anything. Still squishy/soft.
Thanks again!

[aqwut]

Originally Posted by jsr

Thanks guys. Yeah, the weird thing is they didn't get hot during use and didn't puff afterwards. They puffed after sitting around with no use. However, they were sitting in sunlight, so quite a bit of heat since it easily hits 95F+ here. I've even recharged them and they haven't gotten hard or anything. Still squishy/soft.
Thanks again!

I had a small pack getting mushy because I didn't realize that it was hooked up to a UBEC. It was completely drained and had 0 voltage...

[jsr]

I'm bumping this just because I keep reading other threads and other forums where people say that once your LiPos puff, it's near the end and they will explode taking your truck with it in a blaze of glorious flames.

So, how much "puffing" is ok and when do you need to worry about exploding LiPos?

Thanks!

[emaxxnitro]

[ZippyBasher]

When you left them sitting for a couple weeks, Were they fully charged?

Leaving charged lipos for extended periods of time will make them squishy also...

Just an FYI so you dont do it again... Happened to my Dads brand new never used Turnigy and flightmax'

[jsr]

emaxxnitro - WOW! Now that is puffing! Mine aren't nearly that bad. Is your cell hard or still squishy?

ZippyBasher - Yeah, I leave my LiPos charged so that when I have time, I can just grab them to go play.

So, is it only when it reaches emaxxnitro's condition that it's time to not use that pack/cell? Mine aren't nearly that puffed. Mine are about as puffed as the cell next to it (the worse one I have). Mine are all still squishy. I don't know if an "about to blow" puffed cell is supposed to be hard and not squishy???

Thanks.

[emaxxnitro]

thats not my pic, its a fellow rcm members. that is a maxamp 6000 2s 2p
when you cell looks like that its time to stop.
i have seen much worse

[jsr]

Yeah, if I saw mine that bad, I'd definitely stop. I guess there's no hard and fast middle-ground limit of puffing that most people go by for what determines "ok" and what's "churnobyl #2" huh?

[simplechamp]

My policy is to dispose of a cell as soon as it shows any signs of puffing. Luckily, haven't had any cells go on me yet, but when it happens, they'll be gone.

Many people probably think that's stupid or a waste or overreacting. That's fine to think that, you can handle your lipos however you see fit. For me though I'm not going to risk torching my house (possibly with me and others inside) to extend the life of a $50 battery. I would feel the same way if the battery was $1 or $1000.

[jsr]

I completely understand that POV. That's why I asked a while back (this thread is a bit old and I brought it back for more clarification) if puffing was ok and was universally (till now) told it was. Same thing in another forum.

[bryan]

STICK A FORK IN THAT THING CAUSE ITS DONE