Trouble with batteries puffing? Potential help

[CactusJackSlade]

Moderator: If you feel this is in the wrong section, feel free to move - but this should apply to most batteries, so i posted here.

Anyway, I sent back my first battery with only 14 cycles on it. It was "puffed" to the point I was scared to use it or even have it around.

I was about to send my second one back as it was showing signs of puffing at 16 cycles. BTW, I do not abuse my batteries - I even posted this video to show them my typical flights: https://www.youtube.com/watch?v=PYxAhsafOBM

Anyway, I went back to my old school days when Li-Ion batteries first came out. They would get really hot, and that killed them fast. So for no other reason than that I had nothing to lose, I put the Phantom 2 battery in my fridge like we used to do. The swelling "puffing" went down.

Since then I've been refrigerating my batteries after the flight and before charging them - assuming I have access to a fridge. If any battery shows signs of puffing i again put it in the fridge.

This is not a 100% cure as a couple batteries do have slight puffing on occasion, but nothing like before at all.

Give this a try if you are having puffing issues.

Below is one "puffed" battery and one good one:

 

[SteveMann]

Re: Trouble with batteries puffing? Potential fix

There is no "fix" for a puffy LiPo battery - it is trashed. You will quickly watch a battery go from 75% to 15% capacity and autoland wherever it is. Just hope you aren't over water.

 

[CactusJackSlade]

This will (help) keep them from puffing to the extent they get beyond that point.... I have used this method for 3 months now and It has kept my batteries "in check" and the one I thought was on it's way to a "full puff" is still doing well.

But yes, if they are already extremely puffed (like the one in my photo) then it is likely that it is already damaged.... I also changed my title to potential "help" instead of "fix"

 

[Pmcdn]

Re: Trouble with batteries puffing? Potential fix

What causes them to puff up?

 

[CactusJackSlade]

Re: Trouble with batteries puffing? Potential fix

What causes them to puff up?

Well, supposedly:

*when you "abuse them" like running them below 20% capacity on a regular basis
*leaving them at a very low discharge for long periods of time
*leaving them at full charge for long periods of time (supposed to store them at like 50% or so - like when you first got them)
*Charging them when they are hot or charging them too fast
*Poor battery chemistry ("bad batch?")
*storing them in a hot location (store them in a cool place)

There are probably more ways to abuse them, that's off the top of my head and only read about some of them and experienced others. I just try not to do any of those things on the above list...

 

[SteveMann]

Overcharging

 

[crash1sttime]

Overcharging

I thought that the batteries were designed to stop charging when full, thus they wont over charge.

 

[noiseboy72]

There is a subtle but important difference between puffing and swelling.

Swelling is a permanent chemical change within the battery, usually accompanied with internal heating and total loss of battery capacity. The battery will feel hard and will have gained volume, but you will not be able to press the swelling down. This is a total loss and the battery should be safely disposed of asap.

Puffing is a small release of gas from the battery piles into the envelope of the battery. The swelling can be pressed in with a finger. It can be caused by overcharging, but is more often caused by over discharge - in terms of peak current (Going a little beyond the C rating of the battery) or by storing and charging in a hot environment. One of my batteries went like this after being left in a hot car for a couple of days while charged. 3 or 4 discharge cycles and keeping it in a cool room reversed the swelling and 6 months later I am still flying on the same battery without issue and for upwards of 12 minutes - with a heavily loaded 1.4KG P2 & 600mW TX.

I think I am right in suggesting that there are far fewer complaints about battery issues in the cooler months, mainly due to the reduction in puffed batteries from ambient temperature.

 

[GoodnNuff]

Overcharging

I thought that the batteries were designed to stop charging when full, thus they wont over charge.

They are.
And on non smart batteries (i.e. Phantom 1) a quality charger will stop the charge as soon as the battery is full.

Puffing is usually from over discharging then recharging multiple times.

I have a couple of 6S size batteries for my large scale fixed wing, and I've always stored them in the fridge. Seems to prolong their life quite a bit. Storing a charged lipo at room temperature for longer than a week or so is a sure way to shorten the life of the battery. A good quality charger will also allow you to discharge or charge to a safe storage level.

 

[sdtrojan]

I was an EOD troop in the USAF for 12 years and ran our equipment maintenance sections at a couple of units I was assigned to over that time. We had a lot of equipment that was battery operated and we always stored our batteries in a refrigerator. When we deployed, we took a small fridge with us. We liked to keep our beer cold when deployed too.