A fuel cell is an electrochemical cell ( Device that generates electrical energy from chemical reactions ) that converts the chemical energy of a fuel and an oxidizing agent ( It has an affinity for electrons and is ready to accept from other substances ) into electricity through a pair of redox ( Type of chemical reaction in which the oxidation state ( measure of degree of oxidation, loss of electrons of that element ) of substrate change ) reactions.
Hydrogen Fuel Cells
Fuel cell technology involves the reaction of hydrogen with oxygen in the presence of an electrolyte to produce electricity without combustion and mechanical work.
This works like a battery, but it doesn’t want recharging and produces electricity constantly. The efficiency of this is more than combustion fuels.
It consists of 2 plates separated by an electrolyte membrane ( This can be a solid one like a Proton-exchange membrane fuel cell (PEMFC) also called polymer electrolyte membrane(PEM) ). Anode(-ve) and cathode(+ve). Hydrogen passed to the Anode and Air (21% of this is oxygen ) flows over the Cathode. At the anode, hydrogen molecules are split into electrons and protons by a catalyst ( usually carbon materials coated with Platinum). A polymer electrolyte membrane only allows positively charged ions to pass through it, but negative ions can’t. However, an atom needs an equalizing charge to achieve this electron must change its path. At that time electrons are forced through the circuit and generate electric current and heat (electrons flow from the anode to the cathode through an external circuit, producing direct current electricity.). The end product of this is water (4H+4e+O2=2H2O). In the Cathode the hydrogen protons, electrons, and oxygen combine to produce water molecules.
