| 摘要 |
1,195,763. Porous, fuel cell electrodes. COMPAGNIE GENERAL D'ELECTRICITE. 17 May, 1968 [18 May, 1967; 25 May, 1967 and 26 Dec., 1967], No. 23723/68. Heading H1B. [Also in Division C7] Thin porous electrodes having a first, porous layer supporting a second, catalytically active layer of greater porosity is made by depositing on a support by electrostatic projection a finelyscreened powder, sintering the layer of powder thus deposited and compressing it to reduce its porosity and form the first layer, and forming the second layer on the first layer. As shown in Fig. 1, a continuous strip of Ni gauze 1 is coated with carbonyl Ni by electrostatic projector 2 and the coating is then sintered in furnace 3 at 700‹ C. in H 2 and compressed between rolls 4 to form the first layer. The catalytically active layer is then formed by electrostatically projecting a mixture of Ni and Ag 2 O on to the first layer using projector 5, sintering the mixture at 350‹ C. under A in furnace 6, followed by a further sintering under H 2 in furnace 7. Optionally a gas compartment layer can be formed on the strip by depositing more Ni and sintering it using a further electrostatic projector and oven (not shown). Finally, electrostatic projector 8 deposits a waterrepellent such as PTFE on the strip which is cut to size by tool 9. An example describes the preparation of another electrode in which the first porous layer of Ni is sintered on one face of the gauze at 600‹ C., a composition containing a suspension of nickel-boron catalyst and carbonyl Ni in a solution of polystyrene in benzene is coated on the other face of the gauze and the coating is dried at 60‹ C. In another embodiment the first layer is formed by depositing the powder on a metal foil, rolling to compact the powder, stripping the foil from the deposited layer and sintering the layer. |
