Hi,
I have accidentally dropped Li-Po battery of my Quad on asphalt. It fell from about half a meter height. Now I opened up a protective plastic sheet and there is a sign of a damage on one of the corners, see pics.
I am not sure if it is still safe to keep it and fly with it. Should I keep it or should I take it to recycling station?
Replies
I though I would update my post with the latest status. I changed my mind and decided not to destroy the battery instead give it a chance and see what happens.
It has gone 3 months and I am still using the battery without any noticeable changes. I charge always using balance mode and I don't get any difference in the cells beside 0.01 v from time to time, that is 4.19v instead of 4.20v in some cells when fully charged. This is totally acceptable.
I have another undamaged battery from the same batch which I use as a reference. I can say that the damaged battery got slightly bigger in the place where the damage is. I am talking about 1mm at most. I know it because I need to apply more force to push it into the battery holder. Undamaged battery is still sliding in OK.
Here is the latest picture. Since then I charged the battery about 15-20 times. Overall I can say that the flight time has decreased for both damaged and undamaged batteries from 20-25 minutes to around 15-20 minutes which is still OK but I though they would keep their capacity much longer.
Thanks guys for your replies. The battery has not puffed or burned, not yet at least. But I consider it to be a higher risk to charge, discharge or otherwise use it. So I have decided to get rid of it.
I am planning to do a short circuit test with it on the field sometime in the near future. Pic, videos will be posted.
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puffing happens when the battery gets overdrained. It then develops gases inside the protective container which make the cell look more puffed. It may also happen when you leave a battery fully charged over a long time due to temperature fluctuations.