Slight swelling on battery

[eligri]

Hey'a!

Got back from my first flight in a long time with my Mavic Air (1). Noticed the battery was a bit warm (not like HOT, but certainly warm) and perhaps a tad bit swollen. Not golfball swollen but a little swollen.

Is this normal? Can't remember if they always did so. Most of my airplane batteries do, but unsure if my DJI batteries did.

Attached pictures of swelling, taken 5-10 min after flight (about same level of swelling as instantly after).

Was informed that it was normal to have slight swelling, but to keep an eye on it just to be safe.

 

[MAvic_South_Oz]

Has the swelling gone after it's completely cooled ?
If not, then I'd be a bit worried about using it, both from a cell voltage perspective, and from the swelling causing the battery to potentially eject in flight.

I'm not 100% sure if that seemingly minor cell deviation is something to worry about, others might know.

Flying the drone hard, climbing a lot (up and down), in sports mode, or in high wind can make it work a lot harder, draw more current, and cause batteries to heat / swell more.

I would probably test it if the swelling has gone, and take it easy for a flight or two.
If it's a concern, retire it for flights and just use it on the ground for updates and setting changes etc.

 

[eligri]

Has the swelling gone after it's completely cooled ?
If not, then I'd be a bit worried about using it, both from a cell voltage perspective, and from the swelling causing the battery to potentially eject in flight.

I'm not 100% sure if that seemingly minor cell deviation is something to worry about, others might know.

Flying the drone hard, climbing a lot (up and down), in sports mode, or in high wind can make it work a lot harder, draw more current, and cause batteries to heat / swell more.

I would probably test it if the swelling has gone, and take it easy for a flight or two.
If it's a concern, retire it for flights and just use it on the ground for updates and setting changes etc.

I'd say the cells are pretty balanced, atleast compared to other lipo's i've owned.

The battery might still have a slight swelling, hard to say. But certainly not enough to eject it mid-flight. Talking a millimeter deviation, at the most.

Won't be doing any ground work or buying new batteries, I use this drone very seldomly. Mostly just want to know if I need to be very cautious or not

 

[dave canada]

Keep an eye on it if one cell goes bad in it, it will cause a problem and usually only one time but the craft will most likely need repair

 

[eligri]

Keep an eye on it if one cell goes bad in it, it will cause a problem and usually only one time but the craft will most likely need repair

All cells seem decently balanced and no noticable voltage sag. Not talking major swelling for a Lipo here, just a little chunky perhaps.
Ill fly it carefully next time and check if swelling is noticably worse.

Cheers

 

[4006448]

Has the swelling gone after it's completely cooled ?
If not, then I'd be a bit worried about using it, both from a cell voltage perspective, and from the swelling causing the battery to potentially eject in flight.

I'm not 100% sure if that seemingly minor cell deviation is something to worry about, others might know.

Flying the drone hard, climbing a lot (up and down), in sports mode, or in high wind can make it work a lot harder, draw more current, and cause batteries to heat / swell more.

I would probably test it if the swelling has gone, and take it easy for a flight or two.
If it's a concern, retire it for flights and just use it on the ground for updates and setting changes etc.

I’ve just had a similar experience yesterday (18th Dec). It was just after 11am and air temp was around the 30C mark - so it was a hot day. Battery was very warm swapping out and when I put new (cooler) battery in the AC, got message unable to fly (or similar). I’m putting that down to heat. The only thing I can notice with the battery that did suffer slight swelling is that the case has maybe a mm of give; as if the plastic swelled and hasn’t gone back to size. It charged up normally today, just haven’t taken it back out yet. I’m thinking mornings and afternoons in summer here to fly.

 

[MAvic_South_Oz]

I’ve just had a similar experience yesterday (18th Dec). It was just after 11am and air temp was around the 30C mark - so it was a hot day. Battery was very warm swapping out and when I put new (cooler) battery in the AC, got message unable to fly (or similar). I’m putting that down to heat. The only thing I can notice with the battery that did suffer slight swelling is that the case has maybe a mm of give; as if the plastic swelled and hasn’t gone back to size. It charged up normally today, just haven’t taken it back out yet. I’m thinking mornings and afternoons in summer here to fly.

Sure, I think in warm weather like 30c+, it's best to just fly cinematic, nice and slow.
Leave the sports mode, and a lot of ascent etc for cooler weather.

It's just usually too uncomfortable to go outside flying when it hits 35c or more.
I agree, early morning or late afternoon twilight is a great time to fly anyway.