I have 3 batteries for my P4P, a power inverter in the car and the DJI Battery Charging hub that will charge one battery at a time. It works ok unless I'm flying a lot. Today I started with 3 full batteries. I'd put the one I just used on the charger when I grabbed a fresh one. That worked for a little while. Then I got to a point when I couldn't grab a full battery. Are there any chargers that will take care of 2-3 batteries at once?