Patent ID: 6811913
Filing Date: 2004-11-02
Classification: C25B,H01M,Y02E

Abstract:
An electrochemical system adapted to operate between a fuel cell mode, an electrolysis mode, and a mode alternating between said electrolysis mode and said fuel cell mode operating on a fuel gas mixture and an oxygen-containing gas mixture, said system comprising:at least one hollow planar cell arranged to form an electrochemical stack, said stack including an electrical contact structure at each end of said stack; an electronically conductive, substantially impervious, hollow planar separator for separating each cell from an adjacent cell within said stack and electrically connecting each cell to an adjacent cell; a hollow planar, substantially impervious, electrolyte within each cell; a hollow planar fuel electrode contacting said electrolyte, said electrode being on one side of the electrolyte; a hollow planar oxygen electrode contacting said electrolyte and on the opposite side of electrolyte from said fuel electrode; an electronically conductive fuel diffusion layer contacting said fuel electrode, said fuel diffusion layer adapted to allow fuel and oxidized fuel transport via gaseous diffusion between the edge of said layer and said fuel electrode; an electronically conductive oxygen diffusion layer contacting said oxygen electrode, said oxygen diffusion layer adapted to allow oxygen transport via gaseous diffusion between the edge of said layer and said oxygen electrode; a first seal preventing said oxygen-containing gas mixture from accessing said fuel electrode and said fuel diffusion layer; and a second seal preventing said fuel gas mixture from accessing said oxygen electrode and said oxygen diffusion layer.