AFC Components and Configurations

The AFC can be categorized into three main configurations, static electrolyte, mobile electrolyte, and charged electrolyte systems. The Bacon fuel cell is an example of a mobile electrolyte system. In this system, the electrolyte is 

One of the main issues with AFC is that of electrolyte and electrode degradation caused by the formation of carbonate/bicarbonate (CO /HCO3) in the liquid alkaline electrolyte on reaction of OH ions with carbon dioxide contamination in the oxidant stream. Unless pure oxygen is used, CO2 has to be scrubbed from air and electrolyte needs to be replaced often. 

One disadvantage of the mobile electrolyte is it requires extra equipment. A pump is needed to pump the corrosive fluid. The extra pipework means more possibilities for leaks, and the surface tension of the KOH solution 

An alternative to a free electrolyte, which circulates, is for each cell in the stack to have its own separate electrolyte that is held in a matrix material between the electrodes. 

This dissolved fuel t5q e of cell can be used with other liquid fuels such as methanol (Muller et al., 2000 Sinor J. E. Consultants, 1997). An advantage of a liquid fuel like methanol is its high theoretical capacity per volume and weight. 

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