NICKEL ELECTRODE FOR ALKALINE SECONDARY BATTERY AND ALKALINE SECONDARY BATTERY INCLUDING NICKEL ELECTRODE

A battery includes: a container ; and an electrode group housed in the container together with an alkaline electrolyte liquid . The electrode group includes a nickel electrode as a positive electrode and a negative electrode that are combined with a separator interposed therebetween. The nickel electrode includes a positive electrode core and a positive electrode mixture permeated in the positive electrode core. The positive electrode mixture contains nickel hydroxide that is a positive electrode active material. The nickel hydroxide contains a sulfate salt, and a weight rate of a S component contained in the sulfate salt to a Ni component in the nickel hydroxide is 0.28% or more and 1.50% or less.