My P4P batteries are getting really hot in flight (140-155° F)

[timmydjr]

All of my batteries are getting very hot. One got to 155F today. 1-2 weeks ago I had one swell that I had to take out of commission. Is there something in the P4P that could be causing this? This is only recently that this seemed to start happening. Running latest firmware.

Here is one flight for today:

 

[Andy9]

Most likely the cause is the battery. The cell #2 is coming to its end.
I would not fly with this battery any more. If this is the situation with others (you say all of your batteries) then it is the time to buy new. Flying with this one and with similar one is a roulette.