The Electric Car Road Trip Problem - do you have a solution?

The beauty of alternators in the cars we are used to (gasoline powered) is that they charge the battery as the gas keeps the vehicle and the alternator on. So the double battery suggestion is a viable option. One running the vehicle while the other charges off its kinetic energy. Also, for emergency purposes, a rudimentary, somewhat primitive means of "recharging" the vehicle can be implemented (such as a wind-up energy boost for the engine, used in early Fords)