Fuel Cell Stacks and Systems

Stacks

As with all electrical devices, the output power is equal to the current multiplied by the voltage. Individual fuel cells typically generate less than one volt per cell. To achieve a useful voltage, cells are combined in a series into a fuel cell stack.

A stack's total voltage output depends on the number of cells in a stack. The available current depends on the total surface area of individual cells.

System

Producing usable power from a fuel cell requires more than a fuel cell stack. A working fuel cell system includes many components for performing various functions, such as

• Storing hydrogen or other fuels
• Reforming natural gas, methanol or gasoline to obtain hydrogen for the stack
• Pumping hydrogen into the fuel cell stack anode
• Pumping air into the fuel cell stack cathode
• Purging the water produced in the stack
• Monitoring safety and control systems
• Conditioning power output to make the power generated usable
• Cooling the stack and potentially recovering heat for area heating

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