We mentioned storing electricity in a battery. A battery stores energy electrochemically, meaning that electrons are “stored” in a chemical with high energy. Any chemistry that involves electrons as reactants and products is electrochemistry. A fuel cell is similar to a battery: both have two electrodes (anode and cathode) and an electrolyte.
There is more than one way to distinguish a battery and a fuel cell:
- Batteries store their chemicals inside the battery, while fuel cells are fed from outside.
- Fuel cells often involve catalysis, while batteries may not.
- Fuel cells operate continuously. Batteries operate in a batch manner, i.e. charge/discharge.