I acquired a P3 Advantage which uses a 4480mAh (68Wh) 15.2V battery.
I have several P3 Standard batteries which fit, but give a battery signal error.   These batteries are 5200mAh (57.72Wh) and 11.1 V

So wven though they fit in the battery compartment.... is there a compatibility concern?
Thanks.  Mark

Hello Mark, I think the 5200mAh and 11.1 V battery should be Phantom 2 battery.
It's not compatible with Phantom 3 series.