Abstract: A nickel metal hydride secondary battery comprises an outer can and an electrode assembly housed in the outer can together with an alkaline electrolytic solution, wherein the electrode assembly is such that a positive electrode including a positive electrode mixture and a negative electrode including a negative electrode mixture are superimposed with a separator interposed therebetween, the positive electrode mixture includes nickel hydroxide forming a solid solution with zinc as a positive electrode active material and zinc oxide as a positive electrode additive, the negative electrode mixture includes hydrogen absorbing alloy particles and a negative electrode additive, the negative electrode additive is a composite in which yttrium fluoride is supported on carbon black, and a surface of the hydrogen absorbing alloy particles is partially coated with the composite.

Abstract: A hydrogen absorbing alloy negative electrode is provided. The hydrogen absorbing alloy negative electrode has a hydrogen absorbing alloy, and an additive including yttrium fluoride. A mass of the yttrium fluoride is 0.1 parts by mass or more and 0.2 parts by mass or less based on a hydrogen absorbing alloy powder of 100 parts by mass.

Abstract: A negative electrode for an alkaline storage battery that achieves both an improvement in cycle life and an improvement in low temperature discharge characteristics, and an alkaline storage battery including the negative electrode are disclosed. The negative electrode for an alkaline storage battery includes a negative electrode core body formed of metal, and a negative electrode mixture layer which contains at least a hydrogen storage alloy and yttrium fluoride, and is carried on the negative electrode core body. Particles of the yttrium fluoride are formed so that the average particle size thereof is equal to 1 ?m or more and 7 ?m or less.

Abstract: A nickel-metal hydride secondary battery includes an outer can and a group of electrodes housed in the outer can together with an alkaline electrolytic solution. The group of electrodes includes a positive electrode and a negative electrode that are superposed with a separator interposed therebetween, and the negative electrode includes a hydrogen absorbing alloy for nickel-metal hydride secondary batteries, the hydrogen absorbing alloy having a single composition and composed of a plurality of crystal phases.