An electrochemical cell, in particular fuel element, with electrodes made of pulverfoermigen, optionally with binders solidified catalyst material and the same maes strength pore structure

摘要

1,236,872. Electrochemical devices. SIEMENS A.G. 6 Aug., 1969 [6 Aug., 1968], No. 39446/69. Heading H1B. The potential of an electrode consisting of pulverous catalytic material in electrochemical devices, such as fuel cells or batteries, can be made substantially constant over the whole area by compressing the catalytic material hydrostatically or aerostatically in the device by cushions which can be filled with a gas or liquid, and which when there is one cell are disposed outside electrically conductive lead-out gauzes adjacent each electrode, and when there are two or more cells, are disposed at least outside the outermost gauzes, and which when fluidfilled press the gauzes against their adjacent electrodes, thus exerting substantially uniform pressure. A member in which electrolyte is contained is disposed between the electrodes and may comprise a porous supporting structure which is separated from the electrodes by liquid permeable, gas impermeable membranes e.g. asbestos, or the member may be an ion-exchange resin separated from each electrode by a gauze. Other gauzes e.g. a metal or plastics material, may be provided between each of the lead-out gauzes and the cushions adjacent thereto. Preferred devices are those which include means for circulating the fluid through the cushions, means for cooling circulating fluid and/or means for varying the pressure of the fluid in the cushions. As shown, a fuel cell comprises a supporting structure of a coarse-meshed nickel gauze 45, on both sides of which are situated asbestos diaphragms 46 and 47 for the electrolyte, on the outside of which are pulverous electrodes 48, 49 and current lead-outs 50, 51 of nickel gauze. Spacing members 52, 53 consist of metal gauzes and the two end plates 54, 55 are provided with pressure cushions 56 and 57. In a fuel cell described the anode consists of pulverous Raney Ni and the cathode of pulverous Raney Ag, the electrolyte is KOH and the reactants are hydrogen and oxygen.