Hydrogen storage alloy for alkaline storage battery, and alkaline storage battery and alkaline storage battery system each including negative electrode having the alloy

• Main Authors: OCHI, MAKOTO, SUGII, HIROMASA, KITAOKA, KAZUHIRO, KATAYAMA, YOSHINOBU, YOSHIDA, SHUUHEI, TAKEE, MASAO
• Format: Patent
• Language: English; French; German
• Published: 21.09.2011
• Subjects: ALLOYS; BASIC ELECTRIC ELEMENTS; CHEMISTRY; COMPOUNDS THEREOF; ELECTRICITY; FERROUS OR NON-FERROUS ALLOYS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; INORGANIC CHEMISTRY; METALLURGY; NON-METALLIC ELEMENTS; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY; REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGYGENERATION, TRANSMISSION OR DISTRIBUTION; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE; TREATMENT OF ALLOYS OR NON-FERROUS METALS

To provide a hydrogen storage alloy for an alkaline storage battery that improves output power by pulverization of the alloy in the initial stage of partial charge and discharge cycles and that maintains its surface condition to improve the amount of lifetime work (Wh), and an alkaline storage battery and battery system. A hydrogen storage alloy for an alkaline storage battery includes a composition expressed by La x Re y Mg 1 - x - y Ni n - m - v Al m T v (Re: rare earth element(s) including Y; T: Co, Mn, Zn; 0.17‰¤x‰¤0.64, 3.5‰¤n‰¤3.8, 0.06‰¤m‰¤0.22, v‰¥0), and a main phase of an A 5 B 19 type crystal structure. A ratio of X/Y of the concentration ratio X of Al to Ni in a surface layer and the concentration ratio Y of Al to Ni in a bulk layer is 0.36‰¤X/Y‰¤0.85. An alkaline storage battery includes the hydrogen storage alloy in its negative electrode. An alkaline storage battery system performs partial charge and discharge control.