I have been watching mine and have not seen any swelling during or after charging on any of them

CemAygun Posted at 5-30 17:00
Hopefully this is a new battery / break-in thing and it will go away... If not, I also think you should be entitled to a replacement.

I don’t know if it’s just placebo but it does seem like the swelling effect is much lower after the first few charges...

Ice_2k Posted at 5-30 23:14
I don’t know if it’s just placebo but it does seem like the swelling effect is much lower after the first few charges...

They’re not swelling, mine were similar, I have now charged each 5 times they’re exactly the same and nothing like what we seen in M2 batteries, I’m wondering if they allowed a bit more expanding room inside the battery.

Ice_2k Posted at 5-22 02:19
since all 3 batteries in the FMC behaved in the exact same way, I'm assuming it's normal... seems unlikely to get 3 defective batteries....

how close  are they in the serials? Could be a bad charge.

OK, yesterday I was flying in over 90F air and full sun for 25 minutes. I did notice a very slight bulge but not as much as in the photo above. Immediate charging did not exacerbate the slight bulge but the slight bulge did remain after cooling for a day.
The battery uses every bit of depth in it's cavity in the drone (17.6mm). But the cavity bottom is very flexible, so I think the battery would have to swell dramatically before defeating the latch.