I haven't found any explanation for "ether" but can't totally discount what Tesla was doing either. 80 hp from a 12 volt battery would only take a few seconds to discahrge any battery I ever ran across.
Also the guy had an error in that Edison was a DC man and it was George Westinghouse who backed the AC. AC is far more practical in power distribuition since the Edison system needed boost generators about every 8 miles. It was Westinghouse who built the first Electric Chair and Willie Baumer was its first victim.
Check out these solar electric powered cars.
http://www.mit.edu/activities/solar-cars/past.htm