At the cathode, the electrons rejoin the protons and combine with oxygen (usually from the air) to produce the cell's only byproducts: water and heat . Major Fuel Cell Types
Fuel cells are primarily classified by the type of electrolyte they use, which determines their operating temperature and suitable applications. Electrolyte Typical Temp. Common Applications Polymer Membrane 60–180 °C Vehicles (e.g., Toyota Mirai), portable electronics SOFC Solid Oxide (Ceramic) 500–1000 °C Large-scale stationary power, utility plants PAFC Phosphoric Acid 150–200 °C Large-scale stationary power generation MCFC Molten Carbonate Large stationary power, industrial use AFC Space missions (e.g., NASA shuttles) Key Components & Systems Fuel Cell Basics - FCHEA Fuel Cell Fundamentals
Hydrogen fuel is supplied to the anode, where a catalyst (typically platinum) splits the hydrogen molecules into protons ( H+cap H raised to the positive power ) and electrons ( e−e raised to the negative power At the cathode, the electrons rejoin the protons