Development of high-capacity Ni(OH)2 electrode using granulation process

A large-size battery for future industrial applications requires a higher capacity and longer cycle-life than that for the consumer applications. The Ni(OH)2 was granulated with conductive and binder materials, and the granulated particles were sandwiched between two nickel-foam pieces to form a plate-like positive electrode. The capacity was estimated to be 54 mAh/cm2, which was higher than that of the conventional paste-type one (36 mAh/cm2), loading the Ni(OH)2 slurry on the nickel-foam substrate. In this electrode structure, the granulated particles can be easily maintained on the substrate in the electrolyte. The battery test using the granulated Ni(OH)2 electrode showed that the cycle-life performance could be improved by increasing the amount of separator compression. The high compression suppressed the electrode expansion by electrolyte absorption, which causes electrolyte loss during the charge and discharge processes.