ABSTRACT
A key word for the Internet revolution was “concentration to
dispersion” at the end of the 20th century; that is, a large-scaled
computer that dominates everything was converted into a personal
computer or workstation. Recent developments of technology
transmogrified a computer with high performance, for example, to
a portable phone, in the same way as the dispersion launched in the
field of energy, in which fuel cells have an important role. Fuel cells,
which are a generation device made by using the electrochemical
reaction between a fuel (H2) and air (O2), are divided into four
cells on the basis of the kind of electrolytic solution: polymer
electrolyte fuel cell (PEFC), phosphoric acid fuel cell (PAFC), molten
carbonate fuel cell (MCFC), and solid oxide fuel cell (SOFC). Their
characteristics are summarized in Table 10.1. MCFC is currently
being developed and marketed, whereas PEFC that can be easily
operated at low temperature and SOFC with high efficiency have
also attracted attention. In particular, a solid oxide from fuel cells
is an ultimate power generator, which can expect the highest
Ta bl e 10
.1 C h a ra ct e ri st ic s o f v a ri o u s fu e l ce ll s
power generation efficiency among power generators, and since it
is able to collect waste of heat simultaneously, its technology has
attracted attention as a new energy supply system that contributes
to realization of a low-carbon society, in addition to the promotion of
energy saving. Section 10.2 deals with SOFC consisting of Co oxides
as a cathode material.