I would like clarification on my reply from other users..
I would say no, the car charger is rated and designed to charge a 3s battery not a 4s. They will hopefully bring out a new charger for the new batteries.
And this is most likely the wrong forum for this questions, try the P3 forum.
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I think I read in the instructions somewhere that they shouldn't be charged via an inverter through a car 12v cigarette lighter adaptor. May be wrong, I'm too lazy to re-read the manual and bits that came with it but that's where i saw it.