Originally Posted by KeithLuneau
If the car charger is in fact supplying 5V to pin 4, maybe that's the key to using an external lipo for longer duration? I wouldn't try it unless someone else confirms it, and won't be plugging my car charger into my camera until I know for sure that the red wire does in fact go to pin 4...
Who ever gets the new external battery charger with the AA cell in it might be able to confirm that. It operates in parallel with the internal battery, and both charges the internal battery and powers the camera when it's toggled on (according to My Camera Guy). But checking the pinouts on the mini USB is next to impossible without a mating plug adaptor cable for the larger PC USB plug (or unterminated wires) which can easily be checked for voltage and continuity).