| 摘要 |
1521319 Air electrodes for fuel and metal air cells WESTINGHOUSE ELECTRIC CORP 20 Oct 1975 [23 Oct 1974] 42903/75 Heading H1B An air electrode comprises a hydrophilic layer containing (1) about 1 part by weight of oxygen absorption/reduction carbon, (2) 0À5-4 parts of a low oxygen overvoltage material selected from CuWO 4 , NiWO 4 , CoWO 4 , WS 2 , WC and WC containing 1-20% Co and (3) a bonding/non-wetting agent containing PTFE, a metal current collector being moulded into the composite, and a hydrophobic layer laminated to the hydrophilic layer. The electrode may be bifunctional, in which case the carbon is a non-activated carbon such as C black of particle size 0À005-0À13 micron, and surface area 30-600 sq. m./gm., or acetylene black; where the electrode is unifunctional activated C may be used. For the bifunctional electrode, (2) is WC, WC/Co or WS 2 , and is a tungstate or WC/Co for a unifunctional one. Compound (3) may also contain fluorinated ethylene propylene, and the electrodes may contain 0-1À5 weight parts of a catalyst, e.g. Ag, Pt or Ag/Hg; the ingredients are made into a paste with deionized water, pressed on to an expanded metal mesh, wire screen, or fibrous mesh collector of Ni or Ni-plated steel wire, dried, pressed, and then a hydrophobic layer, e.g. containing PTFE, polypropylene and fluorinated ethylene propylene fibres, is hot-pressed to make the laminate; the hydrophilic layer may be 5-100 mil and the hydrophobic 5-20 mil thick; the composite electrode is then placed in a frame of ABS plastics. The electrodes may be used in a hydrogen-oxygen fuel cell, or in a metal air cell; in this case the hydrophobic layer is in contact with the air and the other layer contacts an electrolyte of LiOH, KOH or NaOH; the other electrode is of Fe, Zn or Cd. |
