Young Seung Na, In Seob Song, Young Soo Joung, Mi Jeong Song, Hye Jung Cho, China Patent: CN101853957, (2013-02-20).
The present invention has been made in an effort to provide a fuel cell system having an advantage of stably supplying fuel with low power. According to a first aspect of the invention, there is provided a fuel supply unit for a fuel cell system. The fuel supply unit includes a concentration control unit comprising: a fuel storage chamber configured to provide a stored fuel; a recovered fuel passage member configured to allow passage of a recovered fuel; and a fuel permeation membrane positioned between the fuel storage chamber and the passage member, the fuel permeation membrane being made of a material which is permeable for the stored fuel by diffusion.
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