Page 41 - Introduction to Transfer Phenomena in PEM Fuel Cells
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30 Introduction to Transfer Phenomena in PEM Fuel Cells
1.2.1.9. Metal–air fuel cell
The most common fuel cells in this category are zinc–air batteries,
although aluminum–air or even magnesium–air batteries are also
commercially available. In all cases, the operations (reactions) that take
place are all the same and the specialists have got into the habit of calling
them Zinc Fuel Cells or Zinc–Air Fuel Cells (ZAFC) [LAR 03].
Figure 1.12. Operating principle of a ZAFC
The ZAFC shares some of the characteristics of other fuel cells as well as
batteries. The electrolyte of a ZAFC cell is a solid ceramic material and the
–
ionic conductivity is ensured by the transfer of ions (OH ) (see Figure 1.12).
The ZAFC operates at a temperature of 700°C, which allows it to reform a
large number of hydrocarbons inside the fuel cell, thus avoiding the use of
