文档介绍：Fuel Cells and Applications
S. K. Wang
Dept. of Mechanical and Automation Engineering
I – Shou University
Spring, 2005
1
Chapter 1
Topics:
Introduction, Basic Principles
Efficiency and Open Circuit Voltage, Electrochemistry of Fuel Cells
Operational Fuel Cell Voltages – Real Cell Voltages
Proton Exchange Membrane Fuel Cells (PEMFC)
Alkaline Electrolyte Fuel Cells (AFC)
Medium and High Temperature Fuel Cells (PAFC, MCFC, and SOFC)
Fueling Systems
ponents of Systems
2
Chapter 1
Why fuel cells?
What is a fuel cell?
How does a fuel cell work?
What are concepts of “fuel” and “cell”?
What are the characteristics of fuel cell systems?
What kinds of fuel cells are under developing?
What are the applications of fuel cells?
3
Chapter 1
1 Why Fuel Cells?
Limitation of energy resources: Coal resources can last ~100 years while petroleum can last ~40 years – we are running out of the energy resources.
Environment changes and pollution: Exhaust of carbon dioxide – green house effect, air pollution.
Quest for convenient, safe, and stable energy applications – eg., a handy, non-explosive, and recharge-free battery for cell phones, personal PCs.
Quest for un-centralized, mobile, smaller-capacity electricity generation.
4
Chapter 1
Fuel Cells offer:
A reliable source of energy supply so long as the fuel is available.
A quiet power generation – no moving parts such as engine.
A high efficiency of energy conversion – fuel cell can reach an efficiency of 70% while a Rankine cycle reaches ~35%.
Nearly zero emission – hydrogen fuel cells produce only water.
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Chapter 1
2 What is a Fuel Cell?
A fuel cell is defined as a device which can directly convert chemical energy into electricity through an electrochemistry process.
Indirect conversion: heat engine.
fuel heat doing work
(combustion) (heat engine)
The efficiency of a heat engine is limited by Carnot cycle.
Direct conversion: animal digestion, fuel cells.
food, fossil fuel energy, electricity
(digestion, ele