Difference Between Fuel Cell And Battery- Fuel Cell System Efficiency -voltage Efficiency Of Fue Cel.pptx

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1. Difference Between Fuel Cell And Battery- Fuel Cell System Efficiency -voltage Efficiency Of Fue Cel SlideMake.com

2. Introduction to Fuel Cells and Batteries Fuel cells and batteries are both devices that store and convert energy for various applications. They differ significantly in their operational principles and components. Understanding these differences helps optimize their use in energy systems and transportation.

3. Basic Definition of a Battery A battery stores chemical energy and converts it into electrical energy through electrochemical reactions. It is composed of multiple electrochemical cells connected to produce voltage. Batteries are typically rechargeable or single-use (primary batteries).

4. Basic Definition of a Fuel Cell A fuel cell converts chemical energy from a fuel, such as hydrogen, directly into electricity through electrochemical reactions. It requires a continuous supply of fuel and oxidant to operate. Fuel cells are generally used for continuous power generation applications.

5. Operating Principles of Batteries Batteries generate electricity via reversible or irreversible electrochemical reactions within their cells. They store energy internally and release it when needed. The voltage and capacity depend on the cell chemistry and design.

6. Operating Principles of Fuel Cells Fuel cells produce electricity by combining fuel with oxygen, generating water and heat as byproducts. They operate continuously as long as fuel and oxidant are supplied. The electrochemical process is highly efficient compared to combustion-based power generation.

7. Key Differences in Energy Storage Batteries store energy chemically within their cells, with limited capacity per charge. Fuel cells generate electricity on-demand, requiring external fuel supply. Batteries are generally portable and self-contained, while fuel cells need fuel infrastructure.

8. Efficiency Concepts in Power Systems System efficiency measures the ratio of useful electrical power output to the energy input. Higher efficiency indicates better energy utilization and lower losses. Efficiency varies based on device type, operating conditions, and design.

9. Fuel Cell System Efficiency The overall fuel cell system efficiency includes electrochemical conversion, fuel processing, and auxiliary losses. Typical efficiencies range from 40% to 60% for practical systems. Advanced systems and operational optimizations can improve efficiency levels.

10. Factors Affecting Fuel Cell Efficiency Operating temperature influences reaction kinetics and efficiency. Fuel purity impacts electrochemical performance and longevity. Proper system design and heat management are essential for maximizing efficiency.

11. Voltage Efficiency of Fuel Cells Voltage efficiency refers to the ratio of the actual operating voltage to the theoretical (equilibrium) voltage. It is affected by activation, ohmic, and concentration overpotentials within the cell. Higher voltage efficiency indicates less energy loss during electrochemical reactions.

12. Calculating Voltage Efficiency in Fuel Cells Voltage efficiency (η_v) = (Actual cell voltage) / (Theoretical voltage) × 100%. For example, if the theoretical voltage is 1.23 V and the actual voltage is 0.7 V, then η_v ≈ 56.9%. Improving voltage efficiency involves reducing overpotentials and optimizing cell design.

13. Comparing Battery and Fuel Cell Efficiencies Batteries typically have round-trip efficiencies of 80-90%, depending on technology. Fuel cells exhibit lower system efficiencies but can operate continuously with fuel supply. The choice between them depends on application needs, including energy density and operational duration.

14. Advantages of Fuel Cells over Batteries Fuel cells can provide longer continuous power without recharging. They have higher energy density when fueled properly. Fuel cells produce fewer pollutants and greenhouse gases compared to combustion engines.

15. Disadvantages of Fuel Cells Fuel cell systems require infrastructure for fuel supply and management. They tend to be more complex and costly to manufacture and maintain. Operational efficiency can decrease under partial load conditions.

16. Advantages of Batteries over Fuel Cells Batteries are compact, portable, and easy to install without fuel infrastructure. They have faster response times and are suitable for short-term energy storage. Battery systems generally have higher round-trip efficiencies.

17. Disadvantages of Batteries Limited energy capacity and shorter operational durations without recharging. Reduced performance at low temperatures and aging effects. Environmental concerns related to battery manufacturing and disposal.

18. Practical Applications of Fuel Cells and Batteries Batteries are commonly used in portable electronics, electric vehicles, and grid storage. Fuel cells are favored in transportation (e.g., hydrogen cars), stationary power, and backup systems. Each technology plays a vital role depending on energy demands and infrastructure availability.

19. Future Trends and Developments Advances in materials and system design aim to improve fuel cell efficiency and reduce costs. Battery technology continues to evolve with higher energy densities and faster charging. Hybrid systems combining both technologies are emerging for optimized performance.

20. Summary of Key Differences Batteries store and release energy internally, while fuel cells convert fuel into electricity continuously. System efficiencies vary, with batteries generally having higher round-trip efficiencies. Voltage efficiency in fuel cells is influenced by internal losses and operational parameters.

21. Conclusion and Takeaways Understanding the differences in efficiencies helps in choosing the right technology for specific applications. Improving both system and voltage efficiencies remains a focus for future research. Integrating these technologies can lead to more sustainable and efficient energy solutions.

22. References Fuel Cell Technologies Office. "Fuel Cell System Efficiency." U.S. Department of Energy. Zhang, L., et al. "Comparison of Battery and Fuel Cell Energy Storage Systems." Journal of Power Sources. Larminie, J., & Dicks, A. "Fuel Cell Systems Explained." John Wiley & Sons, 2003.