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A type of [[electrochemical cell]] where [[hydrogen]] and oxygen combine to make water and energy.  Scientists discovered fuel cells in the early 1900s, and they will be important in establishing the [[hydrogen economy]].

A type of [[battery|electrochemical cell]] where [[hydrogen]] and [[oxygen]] combine to make [[water]] and energy.  Scientists discovered fuel cells in the early 1900s, and they will be important in establishing the [[hydrogen economy]].

[[Category: ecology]]

[[Category: ecology]]