めっき技術

Fuel cells

Electrolysis of water produces hydrogen (cathode) and oxygen (anode) by giving electrical energy. Contrarily, water is generated and also electrical energy can be taken out by the reaction of hydrogen on the cathode side and oxygen on the anode side. This is the principle of fuel cells.
Type Features Characteristic value
Phosphoric acid
(PAFC)
- Anode (fuel electrode side): Carbon material
Fuel: Hydrogen, methanol, natural gas

- Electrolyte: High-concentration phosphoric acid
Charge carrier: Hydrogen ion

- Cathode (air electrode side): Carbon material

- Catalyst: Platinum or platinum ruthenium
Low-temperature type
Operating temperature: 160 – 210°C
Uses: Dispersed power systems
Molten carbonate
(MCFC)
- Anode (fuel electrode side): Nickel
Fuel: Natural gas, methanol, naphtha, coal gasification gas

- Electrolyte: Lithium

- Potassium carbonate
Charge carrier: Carbonate ion

- Cathode (air electrode side): Nickel oxide
High-temperature type
Operating temperature: 600 – 700°C
Uses: Dispersed power systems, high-efficiency power generation
Solid oxide
(SOFC)
- Anode (fuel electrode side): Nickel/stabilized zirconia
Fuel: Natural gas, methanol, naphtha, coal gasification gas

- Electrolyte: Yttria-stabilized zirconia (YSZ)
Charge carrier: Oxide ion

- Cathode (air electrode side): Lanthanum manganite
High-temperature type
Operating temperature: 900 – 1,000°C
Uses: Dispersed power systems, high-efficiency power generation
Polymer electrolyte - Anode (fuel electrode side): Platinum
Fuel: Hydrogen, methanol, natural gas

- Electrolyte: Hydrogen-ion exchange membrane
Charge carrier: Hydrogen ion

- Cathode (air electrode side): Platinum
Low-temperature type
Operating temperature: 80 – 100°C
Uses: Automotive power supplies, household power supplies, mobile power supplies
採用事例
Fuel cells
Schematic diagram of fuel cell
(From “Nenryo Denchi no Hon” by the Association of Fuel Cells;
Nikkan Kogyo Shimbun Ltd.)

 

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