9. What are fuel cells? How do they different from battery? Why using ethanol in fuel cells would be better than using it in gasohol E10 or E85?
Fuel cells and batteries are similar because they use a chemical reaction to provide electricity. A battery stores the chemical reactants, usually metal compounds like lithium, zinc or manganese. Once used up, you must recharge or throw away the battery. A fuel cell creates electricity through reactants (hydrogen and oxygen) stored externally. A fuel cell will produce electricity as long as it has a fuel supply. In short, a fuel cell vehicle is refueled instead of recharged.