Verfahren zur Herstellung einer Kontaktplatte für eine elektrochemische Zelle sowie deren Verwendungen

Contact plate in an electrochemical cell having electrodes comprises an injection molded basic body having a through plane conductivity of at least 20 S/cm, and formed of a plastic-graphite composite having a thermoplastic plastic component. The body has at least one plate surface, a media distribution structure recessed in the plate surface, and a contact structure with contact structure elements. Contact plate (7) in an electrochemical cell having electrodes (2, 3) comprises an injection molded basic body (7') having a through plane conductivity of at least 20 S/cm, and formed of a plastic-graphite composite having a thermoplastic plastic component and a mass percentage of at least 70%. The body has openings for supply paths and discharge paths of media reacting at the electrodes. It has at least one plate surface, a media distribution structure recessed in the plate surface defining flow paths for distribution of the medium reacting at adjacent electrodes, and a contact structure protruding from the media distribution structure with contact structure elements for providing electrical contact with an electrode adjacent the basic body. Connections between the media distribution structure on the plate surface and the supply path and discharge path for the media reacting at the adjacent electrodes. The flow paths in the media distribution structure have base surfaces, wall surfaces, and first transitions from the base surfaces to the wall surfaces. The contact structure elements (16) have surfaces in contact with the adjacent electrodes, defining second transitions from the wall surfaces of the flow paths to the surfaces of the contact structure elements. The transitions are all rounded. Independent claims are also included for: (a) a process for producing a contact plate for an electrochemical cell, which comprises: (1) providing the second rounded transitions of the contact structure elements with a rounding radius; (2) constructing the contact structure elements with the second rounded transitions to be at least higher by the rounding radius than required for fitting in a cell stack; and (3) reducing the contact structure elements by at least the rounding radius for avoiding a loss of the surfaces of the contact structure elements; (b) an injection mold for producing a contact plate for an electrochemical cell, which comprises two mold halves defining a parting surface between the halves, and rectangular ejectors having reliefs engaging behind the basic