I have a P3P which is still on firmware 1.4 and have just bought another battery.
The firmware is still on the SD card. Do I need to do any thing other than charge the battery and put it in the phantom and turn it on? I have tried to check the battery firmware on the Go App, but can't see it? Am I safe to fly?!
Thanks.

Hello cookec2, it is recommended to keep the firmware up to date.Besides, the battery's firmware could not be checked separately.

I leave the .bin file on the SD card.  When you start-up, the AC will check if an update is needed for the battery.  I think it take's a moment more than if the .bin isn't on the card but don't know.  Either way - it's a non-event to me and I know everything is up-to-date on the AC and batteries every time I start up.