| 摘要 |
PROBLEM TO BE SOLVED: To provide a nonaqueous electrolyte secondary battery which is high in output in a low SOC and generates a large amount of gas when being overcharged.SOLUTION: In a nonaqueous electrolyte secondary battery, a positive electrode mixture layer 12 includes a first layer 12a including a main surface MS, and a second layer 12b formed closer to a positive electrode current collector 11 than the first layer 12a. In the positive electrode mixture layer 12, the first layer 12a accounts for 20-75 vol.%. The first layer 12a includes a lithium iron phosphate (LFP) 1 and a lithium nickel cobalt manganese complex oxide (NCM) 2. In the first layer 12a, the content of LFP 1 is over 0 to 80 mass% to the total mass of LFP 1 and NCM 2. The second layer 12b includes NCM 2. Further, in the positive electrode mixture layer 12, the content of LFP 1 is 7.5-20 mass% to the total mass of the positive electrode active material. Still further, the maximum pore size of the first layer 12a is 0.50-0.70 μm.SELECTED DRAWING: Figure 5 |
