Last Updated: 2/18/19 by Support
A fuel cell is a type of electrochemical system
that converts the potential energy of a fuel (typically either hydrogen, various hydrocarbons, alcohols, or other organic compounds) into electrical energy through an electrochemical reaction with oxygen or a different oxidizing agent.
Fuel cells are normally two-electrode systems
composed of an anode
and a cathode
separated by a solid or polymeric electrolyte,
as well as separate channels along both the anode and cathode sides for continuous flow of fuel and oxidizing agent, respectively. Multiple layers of anode/separator/cathode are often stacked together into one large matrix to increase the deliverable power. External terminals that facilitate electrical contact with the anode and cathode are also present.
Fuel cells, like batteries,
are a power source; however, unlike batteries, fuel cells do not store energy and they also require continuous input streams of fuel and oxidizing agent to function properly. Fuel cells can provide permanent, uninterrupted power as long as streams are supplied to the anode and cathode continuously. However, over extended use the anode and cathode can lose effectiveness or become poisoned, limiting the lifetime and efficiency of a fuel cell.