Patent ID: 10243196

Abstract:
A positive electrode mixture layer (12) includes a first layer (12a) that has a main surface MS and a second layer (12b) formed closer to the positive electrode current collector (11) side than the first layer (12a). A ratio of the volume of the first layer (12a) to the volume of the positive electrode mixture layer (12) is 20 to 75 vol %. The first layer (12a) contains lithium iron phosphate (LFP) (1) and lithium nickel cobalt manganese composite oxide (NCM) (2). A ratio of the mass of the LFP (1) to the total mass of the LFP (1) and the NCM (2) in the first layer (12a) is more than 0 and 80 mass % or less. The second layer (12b) contains NCM (2). A ratio of the mass of the LFP (1) to the total mass of the positive electrode active material in the positive electrode mixture layer (12) is 7.5 to 20 mass %. A maximum pore size of the first layer (12a) is 0.50 to 0.70 μm.