Electrically conductive gas distribution structure for a fuel cell

: Ledjeff, K.; Peinecke, V.

Abstract
An electrically conductive gas distribution structure (4) for a fuel cell is arranged between a power distribution element (5) and an electrode (3) connected to a diaphragm electrolyte (1). It is arranged flat and disposes of fibres (28) of an electrochemically stable metal, e.g. titanium. It is treated with an abrasive agent to roughen its surface structure (31, 33), e.g. oxalic acid, prior to coating with a hydrophobic polymer layer. As a result of the abutment of the interfaces (43, 44) of the adjacent electrodes (3) and the power draining element (5) with the hard grain areas (33) of the fibres (28), excellent conductivity results across the electrochemical cell formed with this structure (3), whereby a complete hydrophobia of the gas distribution structure (4) is retained through the polymer layers which slide together at these places (43, 44), such that they cannot run together with the water formed in the electrochemical cell acting as a fuel cell. This increases the efficiency of this cell in two ways, the cell being usable as a reversible cell at the same time.