Introduction To 5 Types Of Fuel Cells

A Proton Exchange Membrane Fuel Cell utilizes a proton exchange membrane as the electrolyte. In this type of fuel cell, hydrogen gas is fed through the anode while oxygen gas is supplied to the cathode, with the proton exchange membrane acting as the electrolyte between them. During the electrochemical reaction, hydrogen gas at the anode is split into protons and electrons. While protons pass through the proton exchange membrane, electrons flow through an external circuit, generating electrical power. At the cathode, oxygen combines with protons and electrons, producing water vapor as a byproduct. PEMFCs offer advantages such as high power density, fast start-up time, and high-efficiency conversion, making them widely used in transportation vehicles like cars and light trucks.

An Alkaline Fuel Cell employs a potassium hydroxide solution as the electrolyte. In AFCs, hydrogen gas is decomposed into hydrogen ions and electrons at the anode. Hydrogen ions traverse the potassium hydroxide solution, while electrons flow through an external circuit, generating electrical power. At the cathode, oxygen combines with hydrogen ions and electrons, resulting in water as a byproduct. AFCs exhibit high-efficiency conversion and durability, but due to the corrosiveness of the potassium hydroxide solution, they find widespread application in specific areas like aerospace and defense.

A Phosphoric Acid Fuel Cell employs phosphoric acid as the electrolyte. In PAFCs, hydrogen gas is split into protons and electrons at the anode. Protons migrate through the phosphoric acid electrolyte, while electrons flow through an external circuit, generating electrical power. At the cathode, oxygen combines with protons and electrons, producing water as a byproduct. PAFCs offer high-efficiency conversion and stability, commonly applied in generator sets and cogeneration systems.

A Solid Oxide Fuel Cell utilizes a solid oxide material as the electrolyte. In an SOFC, hydrogen gas is decomposed into protons and electrons at the anode. Protons migrate through the solid oxide electrolyte, while electrons flow through an external circuit, generating electrical power. At the cathode, oxygen undergoes oxidation as it combines with protons and electrons, generating oxygen ions. These oxygen ions pass through the solid oxide electrolyte back to the anode, where they react with hydrogen gas, producing water vapor as a byproduct. SOFCs offer advantages such as high-efficiency conversion, fuel flexibility, and long lifespan, making them commonly used in generator sets and cogeneration systems.

A Molten Carbonate Fuel Cell (MCFC) is also a high-temperature fuel cell that employs molten carbonate as the electrolyte. In an MCFC, the fuel gas typically consists of a mixture of hydrogen and carbon dioxide. These gases are decomposed into carbonate ions and electrons at the anode reaction zone. Carbonate ions can migrate through the molten carbonate electrolyte at high temperatures and, at the cathode reaction zone, combine with oxygen to generate water, carbon dioxide, and electrons. The electrons flow through an external circuit, producing electrical power. The operating temperature of MCFCs generally ranges from 600 to 700 degrees Celsius.