Hydrogen Fuel Cells

Hydrogen Powered Fuel Cell Specification

1. General Description

• Type: Proton Exchange Membrane (PEM) Fuel Cell
• Application: Suitable for vehicles, stationary power generation, and portable devices.
• Advantages:
  • High power density
  • Quick start-up
  • Low operating temperature

2. Performance Specifications

• Power Output:
  • Nominal Power: 5 kW - 100 kW (scalable based on stack size)
  • Peak Power: Up to 120% of nominal for short durations
• Efficiency:
  • System Efficiency: Approximately 50-60% (LHV - Lower Heating Value)
  • Peak Efficiency: Up to 65% under optimal conditions like full load and ideal temperature
• Voltage:
  • Nominal Voltage: Variable, typically around 40-60 V per cell stack
  • Operating Voltage: 0.6-0.8 V per cell, depending on load and hydrogen quality
• Current Density:
  • Max Current Density: 1.5 A/cm², can vary with membrane and catalyst efficiency
• Response Time:
  • Startup Time: Cold start less than 30 seconds (from -20°C to operational with pre-heating)
  • Load Response: Immediate response to load changes due to quick proton exchange

3. Fuel Specifications

• Hydrogen Quality:
  • Purity: ≥99.97% to prevent catalyst poisoning
  • Maximum Impurities:
    • Water: <5 ppm
    • CO: <1 ppm, as it can poison the platinum catalyst
    • O₂: <2 ppm
    • Other hydrocarbons: <2 ppm
• Fuel Pressure:
  • Operational Pressure: 1-5 bar (variable by system design for optimal diffusion)
• Fuel Storage:
  • Type IV composite hydrogen cylinders for high-pressure storage
  • Liquid hydrogen tanks for larger systems or long-duration storage

4. Environmental & Operating Conditions

• Operating Temperature:
  • Cell: 60°C to 80°C for efficient proton exchange
  • System: -20°C to 50°C (ambient) with appropriate cooling and heating mechanisms
• Humidity:
  • Operating Humidity: 20% to 95% RH, membranes require hydration for conductivity
• Altitude:
  • Operational: Up to 2,000 meters without derating, higher altitudes may require pressure adjustments

5. Durability & Lifetime

• Lifetime:
  • Expected: >5,000 hours for automotive; up to 40,000 hours for stationary applications
  • Degradation Rate: <10 µV/h under normal operation
• Cycling:
  • Start/Stop Cycles: >10,000 for automotive applications due to frequent use

6. Physical Specifications

• Dimensions:
  • Varies by application; for a 100 kW system, approximately 1 m³ including auxiliaries
• Weight:
  • Approximately 50-100 kg per 50 kW (excluding hydrogen storage, varies with materials used)

7. Safety Features

• Hydrogen Leak Detection: Integrated sensors for immediate action
• Thermal Management: Cooling systems to maintain optimal temperature and prevent overheating
• Overpressure Protection: Pressure relief valves and system shutdown capabilities
• Electrical Safety: Compliance with IEC 62282-3-100 for fuel cell systems to ensure no electrical hazards

8. Standards Compliance

• ISO 22734: Hydrogen generators using fuel processing technologies
• ISO 14687: Quality of hydrogen for PEM fuel cells
• IEC 62282: Fuel cell technologies

9. Maintenance

• Service Intervals: Annual inspection recommended; component-specific maintenance as per manufacturer's guidelines
• Maintenance Tasks:
  • Replacement of air filters
  • Cleaning or replacement of humidifiers
  • Inspection of electrical connections

10. Environmental Impact

• Emissions: Water vapor as primary byproduct; zero CO2 emissions during operation, contributing to reduced greenhouse gas emissions