BIPOLAR ELECTRODE FOR NICKEL-METAL HYDRIDE STORAGE BATTERY AND NICKEL-METAL HYDRIDE STORAGE BATTERY

摘要

PROBLEM TO BE SOLVED: To provide a bipolar electrode for a nickel-metal hydride storage battery, which has excellent charge/discharge performance and can suppress peeling-off or falling-off of an active material layer from a metal foil and an increase in internal pressure of the battery, and a nickel-metal hydride storage battery provided with such a bipolar electrode.SOLUTION: A bipolar electrode 1 includes a metal foil 2, a first active material layer 3 provided on the front side surface of the metal foil 2, and a second active material layer 4 that has a larger area than the first active material layer 3 and is provided on the back side surface of the metal foil 2. The second active material layer 4 includes a low density region 41 disposed at a peripheral part in a plan view from the thickness direction of the metal foil 2 and a high density region 42 disposed on the inner side than the low density region 41 and has a lower porosity than that of the low density region 41.SELECTED DRAWING: Figure 2