Is this LiPo in trouble?

[911hillclimber]

Bought a battery for the plane 5 years ago, but never used it.

Noticed today the outer casing has swollen and is soft to the 'squeeze'.

Have put it out in the middle of the garden to be safe, but should i discard it?

[J D 8]

   Unusual for an unused lipo to puff up so something is odd about it. Best got rid of I recon.

[911hillclimber]

Agree, and the other models that are rapidly accumulating are on 2200 3 cells, so will use this battery size for the Stol as and when it takes to the air.

Thanks for the reply.

Graham.

[Kim Taylor]

Discharge it completely using a lightbulb other load so that it can't combust, then dispose of it in whatever way you feel comfortable.

Which reminds me - I've got a 3200 3s which has dropped a cell which I need to dispose of...................

There's always something!!

As you've already realised, it's best to use the same battery size across as many models as you can

Kim

[Chris Walby]

I had a rather tied and well used 4S3300 that had gone a bit puffy. Capacity was down and it lacked punch (used in a yak and edf), but ok for most models so I popped it in the IC starter.

 

It was used many times over the next few months until it lacked a bit of go, checked it and its was about 15% so put it on the clubhouse battery supply to charge at 1C. Went out for as fly with the IC, 10 min max and returned to the clubhouse to find an acrid smell and a very puffy lipo on the Melamine table. Needless to say it was removed at arm's reach with the fire extinguisher at the ready.

 

My lipo rule, if its not suitable for a model then its time it met the recycler and dropping them below 20% is a good way of shortening their life. 

[MattyB]

8 hours ago, Kim Taylor said:

Discharge it completely using a lightbulb or other load so that it can't combust, then dispose of it in whatever way you feel comfortable.

That is the correct way to dispose of lipos, but before you do check the cell voltages via the balance lead - you may well discover the pack was stored at an elevated state of charge I.e. >4V/cell) which over time will kill it.
 

Re: disposal, some still espouse the saltwater method, but it’s incredibly ineffective (the contacts corrode faster than the pack discharges resulting in a partially discharged pack with no way to discharge further, the worst result) and results in lithium pollution of the water. This method needs to be consigned to the dustbin of history! Instead just fully discharge over a load, cut off the connector, twist the wires together and dispose of in battery recycling or your general refuse bin.

Edited June 2, 2021 by MattyB

[Philip Lewis 3]

I agree 99% with what Matty B said above, personally I don't cut the connectors off as I'm not going to reuse old connectors anyway, I plug them together to show the recyclers that the pack is dead (pretty much the same as twisting bare wires together I agree).

 

Just the last three words, Lithium is a finite resource, it's an element, it can't be made but it's very recyclable, so recycle it and please don't just put it in with the general refuse and risk it being sent to landfill, who knows if we recycle enough of it then the price might even come down.

 

Our local recycling plant bizarrely won't take wood but they are quite happy taking Lithium batteries, go figure that one!.   

[Andy Stephenson]

When LiPos first became popular for Eflight a puffed battery signalled the end of life but more recently I have seen plenty of puffed packs that perform perfectly satisfactorily. Before disposing of the battery I would test the voltage of all the cells and if they are close then I would charge it in a safe place. More often than not the gas causing the puffing will be absorbed and will look normal again.

[J D 8]

           While I mostly agree with the above [ I have a couple of hard worked overlander 2200's that are a bitt puffed but still work in a lower demand plane and balance fine ] The OP's batt had puffed up in storage, not normal.

 

When it comes to battery's of all types including large lead acids [ Tractor bat's] if they start behaving outside of their normal operation its time to think of replacement.

[MattyB]

 

1 hour ago, Philip Lewis 3 said:

Just the last three words, Lithium is a finite resource, it's an element, it can't be made but it's very recyclable, so recycle it and please don't just put it in with the general refuse and risk it being sent to landfill, who knows if we recycle enough of it then the price might even come down.

 

Agreed, but unfortunately in some places that isn't possible - when I asked the guys at the local recycling centre where to put lipos he said where I live they are not currently recycled, so they had to go in general refuse ☹️

[MattyB]

1 hour ago, Cassandra said:

The last time I took a pack apart, I am pretty sure that the tabs on the cells were stainless steel. I feel an experiment coming on.

 

Experiment if you wish, but at the end of the day any method that requires puncturing and/or disassembly of packs in order to work seems to me to be extremely unwise for several reasons, most obviously the chance of fire (especially with a puffed pack that has a decent amount of gaseous oxygen present). Slow discharge over a suitable load is so much safer and more consistent; you can get device that plugs straight in to the connector to do this now (though they would take a long time to discharge a big pack).

 

Some more options for safe discharging...

 

Edited June 2, 2021 by MattyB

[Ace]

Regarding recycling, there could be more options than just a council recycling center? 

See here for responsibilities for anyone who currently sells over 32kg of batteries PA. That should cover a lot of retail outlets increasing opportunities to dispose/recycle safely.

[Lima Hotel Foxtrot]

2 hours ago, MattyB said:

 

 

Agreed, but unfortunately in some places that isn't possible - when I asked the guys at the local recycling centre where to put lipos he said where I live they are not currently recycled, so they had to go in general refuse ☹️

Hmmmm. Methinks they are misinformed. If they recycle laptop and phone batteries, they should take a lipo. They're all lithium batteries after all. My local tip/recycling place just has a big bin for that purpose along with separate bins for domestic nickel and lead acids. 

[MattyB]

1 hour ago, Lima Hotel Foxtrot said:

Hmmmm. Methinks they are misinformed. If they recycle laptop and phone batteries, they should take a lipo. They're all lithium batteries after all. My local tip/recycling place just has a big bin for that purpose along with separate bins for domestic nickel and lead acids. 

 

Yes, I was surprised and suspect you are right, but at the end of the day they did not have anywhere for them as loose lipos (despite there being a large stack of electronic devices conteining batteries right next to him!).

[john davidson 1]

A not very old 4,000Mah 5cell of mine went sick , on test one cell was duff and I had previous bad experience trying to convert a 5cell to four by trying to physically separate one.  I actually found  a good use in a 12volt lantern torch , one of the ones with a tungsten car bulb , and powered by a lead acid.The bulb tolerates the  slight overvoltage and you can heat your hands too. Used for two years so far so a good use for an ex £50 battery

[911hillclimber]

New charger from 4-Max arrived today.

Not all that simple, but looks good.

Hope to use both my 2200 LiPo's tomorrow down to 20% and see how we fare.

[MattyB]

10 hours ago, 911hillclimber said:

New charger from 4-Max arrived today.

Not all that simple, but looks good.

Hope to use both my 2200 LiPo's tomorrow down to 20% and see how we fare.

 

Based on your previous information I suggest you set your timer to 6 mins, land and check the cell voltages at that point. If they are still above 3.6V/cell add a min to the timer and repeat until you get to the 3.6V mark. This is a reasonable cell cut-off voltage, and allows a littel headroom for the loss of capacity that occurs in cold weather.