Fuel Cells: Hydrogen-Oxygen Fuel Cell

What is a Fuel Cell?

• A type of electrochemical cell.
• Converts energy between electrical and chemical forms.
• Transforms chemical energy into electrical energy.

Hydrogen-Oxygen Fuel Cell

• Most common type of fuel cell.
• Combines hydrogen and oxygen to form water and generate electrical energy.

Structure

• Electrolyte: Central solution allowing ions to move; commonly potassium hydroxide.
• Electrodes:
  • Negative anode (left), positive cathode (right).
  • Made of porous carbon containing a catalyst.
• Compartments:
  • Anode compartment (left) with hydrogen inlet.
  • Cathode compartment (right) with oxygen inlet.
  • Outlets for water and heat at the cathode.

Operation

1. Hydrogen Oxidation:
   • Hydrogen enters the anode compartment.
   • Oxidized by the anode (hydrogen atom loses an electron).
   • Electrons travel through the wire to the cathode.
   • Hydrogen ions move through the electrolyte.
2. Reaction at Cathode:
   • Electrons and hydrogen ions react with oxygen.
   • Form water, leaving the cell via outlet.
3. Key Equations:
   • Oxidation of hydrogen.
   • Reduction of oxygen.
   • Overall equation: Combines oxygen and hydrogen to produce water.

Electrical Energy Generation

• Driven by the movement of electrons through the wire.
• Powering electrical devices via chemical reactions.
• Key points:
  • Fuel (hydrogen) is oxidized.
  • Sets up potential difference across the cell.
  • Drives electron flow to generate electricity.

Pros and Cons of Hydrogen-Oxygen Fuel Cells

Advantages

• Use of abundant hydrogen and oxygen.
• No carbon dioxide or pollutants produced.
• Simplicity leads to longer lifespan than batteries.
• Less polluting disposal compared to batteries.

Disadvantages

• Storage issues due to hydrogen being a gas.
• Safety concerns as hydrogen is explosive when mixed with air.
• Production of hydrogen fuel requires energy typically from fossil fuels.

Conclusion

• Potential use as replacements for fossil fuel engines and batteries in vehicles.
• Highlighted benefits and challenges in adopting hydrogen-oxygen fuel cells.