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Metal hydride electrodes with copper-encapsulated alloys and non-coated alloys were fabricated using suitable conductive and binding agents. The charge-discharge characteristics of three kinds of hydride electrodes were comparatively investigated. The encapsulated alloy electrode is remarkably superior to the non-coated LaNi5-based one, discharging at a high rate and exhibiting a smaller capacity decay at the stage of cycle tests. The hydride alloy quality of hydride electrodes can be effectively determined by measuring rate capability. The results of vented cell experiments confirm that the capacity decay of non-coated alloy electrodes in sealed cells is not due to the oxidation of oxygen from the nickel hydroxide positive electrodes. The relationship between the equilibrium potential of hydride electrode and the equilibrium hydrogen pressure has been deduced by a succinct thermodynamic method, without consideration of the unknown activity of water and fugacity coefficient of hydrogen.

The flexible plaque of porous nickel is crucially important for the cycle life of nickel/cadmium, nickel/hydrogen and nickel/metal hydride batteries. The use of hollow fiber can increase the flexibility of porous plaque. The sintered porous plaque containing hollow nickel fiber is fabricated by a traditional. slurry-scraping technology. The pore-creating agent and the pore-strengthening additive are applied to increase the plaque porosity and optimize the pore structure. Nickel hydroxide is used as a pore-strengthening agent and it also assists the gasification of organic pore-creating agent to some extent. The plaque porosity reaches more than 88% when using thinner skeleton and large amount of hollow fiber.