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4
Thermodynamics of Fuel Cells
Thermodynamics and electrochemical kinetics describe the energy conver-
sion process, performance, and ratings of a fuel cell. As we have described in
Chapter 2, the kinetics associated with the electrochemical reactions are critical
in describing the real performance of an electrochemical fuel cell. While the rate
of a single-step electrochemical reaction is described by the electrode kinetics,
thermodynamics, however, establishes the maximum theoretical limit for the
performance of an electrochemical fuel cell like in any other energy conversion
devices including the heat engine. In an open circuit fuel cel