Patent ID: 7438984

Claim:
An electric system for a fuel cell, comprising: a fuel cell for generating electric power by being supplied with a reactive gas; a first power supply line connected to said fuel cell; a first electric accessory serving as at least part of a fuel cell accessory for operating said fuel cell, said electric accessory being connected to said first power supply line for being supplied with electric power from said first power supply line; an auxiliary electric system operable under a voltage lower than a voltage output from said fuel cell; and a first DC-to-DC converter for performing bidirectional voltage conversion, said first DC-to-DC converter connecting said auxiliary electric system to said first power supply line; said auxiliary electric system comprising: a first electric storage device; a second power supply line connecting said first electric storage device and said first DC-to-DC converter to each other; and a second electric accessory serving as an electric accessory other than said fuel cell accessory, wherein a portion of said second electric accessory being connected to said second power supply line through a second DC-to-DC converter, wherein the second electric accessory is supplied with electric power from said second power supply line.