6.11 Hydrogen Fuel Cells

• A hydrogen fuel cell converts chemical energy from hydrogen into electrical
• The overall reaction in a hydrogen fuel cell is2H_{2} + O_{2} \rightarrow 2H_{2}O</latex>
• At the anode of a hydrogen fuel cell, hydrogen is split into protons and electrons
• The electrolyte in a hydrogen fuel cell allows electrons to pass through.

  False
• One type of hydrogen fuel cell is the Proton Exchange Membrane (PEM) fuel cell, which uses a polymer membrane
• Solid Oxide Fuel Cells (SOFCs) operate at high temperatures around 800-1000°C.
• Alkaline Fuel Cells (AFCs) use a potassium hydroxide solution
• PEM fuel cells are commonly used in vehicles due to their quick start-up time.
• The chemical reaction in a hydrogen fuel cell produces electricity and water
• Match the type of hydrogen fuel cell with its electrolyte:

  PEM ↔️ Polymer membrane

  SOFC ↔️ Solid oxide material

  AFC ↔️ Potassium hydroxide solution
• The electrons in a hydrogen fuel cell flow through an external circuit to generate electricity.
• What is the working principle of a hydrogen fuel cell?

  Electrochemical conversion
• At the anode, hydrogen is split into protons and electrons
• In a hydrogen fuel cell, protons flow through the electrolyte.
• What combines with oxygen at the cathode in a hydrogen fuel cell?

  Protons and electrons
• The byproduct of a hydrogen fuel cell is water
• The anode in a hydrogen fuel cell splits hydrogen into protons and electrons.
• What is the function of the cathode in a hydrogen fuel cell?

  Combines protons and electrons
• The electrolyte in a hydrogen fuel cell allows protons to pass through
• What is the overall reaction in a hydrogen fuel cell?

  2H_{2} + O_{2} \rightarrow 2H_{2}O</latex>
• Match the type of hydrogen fuel cell with its electrolyte:

  PEM ↔️ Polymer membrane

  SOFC ↔️ Solid oxide material

  AFC ↔️ Potassium hydroxide solution
• PEM fuel cells operate at low temperatures.
• What is the operating temperature range of SOFC fuel cells?

  800-1000°C
• The electrolyte in a fuel cell determines the type of ions that move
• Match the energy source with its primary emission:

  Hydrogen Fuel Cells ↔️ Water vapor

  Fossil Fuels ↔️ CO2, pollutants

  Solar Power ↔️ None
• What is the efficiency range of fossil fuels as an energy source?

  30-40%
• Hydrogen fuel cells produce only water vapor
• Hydrogen fuel cells have an efficiency of 40-60%
• Fossil fuels produce water vapor as a byproduct.

  False
• Match the energy source with its typical efficiency:

  Hydrogen Fuel Cells ↔️ 40-60%

  Fossil Fuels ↔️ 30-40%

  Solar Power ↔️ 15-20%

  Batteries ↔️ 80-90%
• Hydrogen fuel cells produce only water vapor
• Steps in the working principle of a hydrogen fuel cell:

  1️⃣ Hydrogen is split into protons and electrons at the anode

  2️⃣ Protons pass through the electrolyte

  3️⃣ Electrons flow through an external circuit

  4️⃣ Protons and electrons combine with oxygen at the cathode

  5️⃣ Water is produced
• What is the function of the anode in a hydrogen fuel cell?

  Splits hydrogen
• What is the overall reaction in a hydrogen fuel cell?

  $2H_{2} +$$O_{2} \rightarrow 2H_{2}O$
• PEM fuel cells use a polymer membrane
• Match the fuel cell type with its characteristic operating temperature:

  PEM ↔️ Low (around 80°C)

  SOFC ↔️ High (800-1000°C)

  AFC ↔️ Moderate (150-200°C)
• What is the typical efficiency range of hydrogen fuel cells?

  40-60%
• The only byproduct of hydrogen fuel cells is water vapor
• What are two common methods for producing hydrogen?

  Electrolysis and SMR
• Storing hydrogen gas requires high pressure or low temperatures.