LIPO gone fat

[Bernie]

I have a 3s lipo and it is puffing up over a period of 3 weeks .haven't used it for months.been stored .I'm a bit jittery about it going pop like they do! what should I do .?  Cheers Bernie

Edited By Bernie on 09/10/2013 15:55:36

Edited By Bernie on 09/10/2013 15:56:04

[crispin church]

check on meter if 3 cell still charged ok then use it a little puffing up dont hurt

if its flat try a slow charge and see what happens just dont charge it on the wifes new dinning room tabble

[Bill_B]

LiPos are cheap enough these days so I wouldn't continue using it as it's only a matter of time before it's completely u/s. Why take the risk of it possibly destroying a plane, or worse, your property. It's time for it to have two weeks holiday in a salt bath until dead! It can then be safely disposed of.

[PatMc]

About 6 years ago I emailed these photos to Hobbycity (now Hobbyking) at their request after I'd complained about them swelling.

Although they were all replaced FOC I kept using them. After a few months the replacements also swelled but both the new & originals continued to perform OK. I was always careful about charging them under supevision & how they were stored. The 1300s have only been used at low rates in vintage models & are still in use.

This is the final 3 of the 2200s that were scrapped a couple of months ago. Out of curiosity I removed the outer heat shrink from one of them (guess which one ).

[Capt Kremen]

Like PatMc, I've had LiPo packs from all vendors, (cheap and expensive so called 'superior' brands), used them in Vintage and sports models at very modest current, they've all eventually puffed up. Some sooner than others.

Have monitored individual cells, balanced packs, balance charged at 1C or less and stored at 'storage voltage' if not flying, still all brands have puffed. I have come to accept this fact as almost an inevitability.

Strange as my EDF high current packs have shown no sign (yet) of swelling despite their 'hard' use.

I wonder whether I care too much and should just charge (high rate), fly (high discharge current), and not bother pack balancing other than when attached to the charger. TLC doesn't seem to have paid off for me. Any thoughts experts?

[Bernie]

Thanks for all you'r inputs .This one was a cheapy off ebay but still works I tried it this afternoon and it was perfect ,I must admit just before starting this thread I freaked out a bit as I don't want it bursting into flames in my workshop with all my models so I deposited it in my BBQ it sat there for a couple of hours and seemed to go down slightly . I take on board everything said and thanks.

[PatMc]

Bernie, I always store my lipos in the garage in a couple of pyrex casserole dishes with the lids in place - bought them in either Aldi or Lidl quite cheaply.

[Richard Cooper]

What a great help these posts have been: I have one fat Hyperion Lipo and one slightly swollen. Both are charged but not used for 4 months or so. They are working well with minimal heating on test runs to 60% discharge at 50% C.

Bill_B Please explain the Salt bath for the disposal of a bad LIPO! Do you discharge it first?

The Pyrex dish idea sounds excellent, well done.

[Toni Reynaud]

I seem to recall reading somewhere that if you take a puffed LiPo and place it under a housebrick when charging, it tends to make the internals re-absorb the gas and return the cells to a hard state. I haven't tried it, but I have been using slightly puffed packe for a couplke of years with no problems. As insurance, they are always charged/balanced outside, and stored in the workshop inside a thick metal toolcase. I also take them to the field in an insulated box with a handwarmer in it to keep the temperature up.

[Masher]

But Toni - you then put your puffed pack into a model and fly it where it is under more stress - is it worth the risk?

As somebody else said they are so cheap, just replace

Edited By Masher on 08/03/2014 08:54:28

[Toni Reynaud]

I'm not talking using them puffed to the state shown in the pictures above, just slightly puffed. I'm happy with doing that. I check the cell voltages and when one cell gets to be too far out of line with others, that's the time for the battery to be consigned to the tip. I have yet to see a LiPo go up in smke and flames. Ive seen several bent and unuseable after crashes, but that's a differnt ballgame altogether.

[John Privett]

Posted by Richard Cooper on 08/03/2014 06:41:02:

Bill_B Please explain the Salt bath for the disposal of a bad LIPO! Do you discharge it first?

The idea is that salt water conducts electricity, so dropping the battery into it means that all the cells slowly discharge to zero - which is why Bill says to leave it there for a couple of weeks.

[Braddock, VC]

Rats! I threw away 3 batteries for my radian as they were puffed up.