Glossary of fuel cell terms

The Glossary of fuel cell terms lists the definitions of many terms used within the fuel cell industry. The terms in this fuel cell glossary may be used by fuel cell industry associations, in education material and fuel cell codes and standards to name but a few. Activation loss See overpotential Adsorption Adsorption is a process that occurs when a gas or liquid solute accumulates on the surface of a solid or a liquid (adsorbent), forming a film of molecules or atoms (the adsorbate). Alkali In chemistry, an alkali is a basic, ionic salt of an alkali metal or alkaline earth metal element. Alkali anion exchange membrane An alkali anion exchange membrane (AAEM) is a semipermeable membrane generally made from ionomers and designed to conduct anions while being impermeable to gases such as oxygen or hydrogen. Alkaline fuel cell Alkaline fuel cell (AFC) also known as the Bacon fuel cell. Alloy An alloy is a solid solution or homogeneous mixture of two or more elements, at least one of which is a metal, which itself has metallic properties. Alternator An alternator is an electromechanical device that converts mechanical energy to alternating current electrical energy. Alternating current An alternating current (AC) is an electric current which reverses direction cyclically, as opposed to direct current, the direction of which remains constant. Ambient Air The air surrounding a given object or system. Ambient temperature Ambient temperature is the temperature within enclosed space. Ampere The ampere, in practice often shortened to amp, (symbol: A) is a unit of electric current, or amount of electric charge per second. Anion A negatively charged ion; an ion that is attracted to the anode. Anode An anode is an electrode through which electric current flows into a polarized electrical device. Aqueous phase reforming APR is the production of hydrogen from biomass-derived oxygenated compounds (such as glycerol, sugars and sugar alcohols). Artificial membrane An artificial membrane, also called a synthetic membrane, is a membrane prepared for separation tasks in laboratory and industry.