I've not flown my PHV3 in a few weeks.  Just launched it to test something and the app said a 'battery upgrade' was required.  Never seen that before.  had 62% charge so I did my launch and no problems.  

What is it asking for?

Your battery need to be updated. Put the Firmware last update on the card (not in the directory, on the root path) and in the P3, turn it on and after about 90 sec (When you hear 4 beep repeatetly. When your hear the Beep [silence] Beep,Beep repeatetly) your battery will be updated.

novoweb Posted at 2015-8-24 10:06
Your battery need to be updated. Put the Firmware last update on the card (not in the directory, on  ...

Thanks.  Had no idea batteries need that

tonycorsoimages Posted at 2015-8-24 23:30
Thanks.  Had no idea batteries need that

So... when you do a firmware update on the P3, if you have more than one batterie, update your batteries also.

novoweb Posted at 2015-8-25 06:36
So... when you do a firmware update on the P3, if you have more than one batterie, update your bat ...

That certainly explains why one of my three batteries works fine then.
Thanks