How do you convert electric energy to chemical energy?
-- charge a battery
-- plate your silver
a battery is a device used to convert chemical energy into electric energy and has not an indefinite timespan, when whole of chemical energy is converted into electric energy which is used in one way or the other, then their is no more interchangable chemical energy left. So we have to recharge the battery which converts the applied electrical energy back into chemical energy which can later be reused as described earlier.