A FUEL CELL is a special galvanic cell that produces electrical energy with a chemical reaction between hydrogen and oxygen. A fuel consists of electrodes separated by membrane or electrolyte.
The fuel cell produces electricity and heat. Because of its high capacity and efficiency, the fuel cell with a membrane made of polymeric electrolyte is especially suitable for use in cars. In it, the plastic membrane of PEM works in the role of electrolyte, which can transfer protons, its operating temperature of about 80 Celsius.
So a fuel cell is a device that allows us to convert the chemical energy of the fuel directly into electrical energy. In the case of hydrogen, it is combined with oxygen into water or water vapor. This produces electricity that charges the battery or drives the vehicle.