I have 6 batteries and I had a location shoot without a place to plug in my chargers.  Needless
to say I used them all and barely got what I needed.  On the DJI store site it shows a car charger for
the P2 but not the P3 batteries.  I went to a nearby auto parts store but the 100 watt inverter wouldn't
work with the charger.  Any ideas, other than buying more batteries?

There is a very low cost car charger available via eBay: http://www.ebay.com.au/itm/Car-C ... :g:32cAAOSw5ZBWFenF

I bought one and it works just fine, although slower than the mains charger.

You can use an inverter to run the DJI charger, but people report varying issues with them, some will not work, some say it must be a pure sine wave inverter, just a suck it and see exercise really. However it is not an efficient way of doing it as there are accumulated losses in using an inverter.

I got this one and it works really well:
http://www.amazon.com/gp/product ... _detailpage_o07_s00

Order a 200 watt inverter. I would trust the DJI charger many more times than one of these after market chargers that could be supplying incorrect voltage or current to the $150 battery. Besides, it'll likely charge it faster and some inverters have 2 plugs so you can get 2 to charge at once!

Gamerfanatic Posted at 2015-11-5 12:07
Order a 200 watt inverter. I would trust the DJI charger many more times than one of these after mar ...

Yes, the DJI charger is certainly faster, but the one I linked to is not that much slower. Using an inverter is a waste of power, as the after-market device can supply the voltage required directly. There is nothing in the DJI charger that is critical, all the battery requires is a raw supply of around 17.5 volts, all the smarts for controlling the charge are in the battery itself.