You can't take into account the fuel used to produce electricity to charge a battery as a way to claim it as not 100% emission free. If you did, then you are not 100% emission free as the fuel you use has to be processed, in a facility that is using electricity. Then it would have to be transferred by some means , and ultimately delivered in a truck burning fossil fuels. Thus, by your reasoning it makes your system not 100% zero emission either.