Lithium-ion secondary battery inspection method and lithium-ion secondary battery inspection program

摘要

PROBLEM TO BE SOLVED: To provide an inspection method and an inspection program for a lithium ion secondary battery capable of quickly and appropriately determining the precipitation tendency of lithium in a negative electrode. SOLUTION: The inspection method of a lithium ion secondary battery is based on a measurement step of measuring a resistance value for each of a region 35 in which a negative electrode active material layer 32 is divided in a grid pattern, and a resistance value R of a region 35 to be determined. A resistance difference calculation step of calculating the resistance difference R-Rn, which is a value obtained by subtracting the resistance value Rn of another region 35 adjacent to the region 35, for each of the other regions 35, with all the regions 35 as determination targets. When the number of resistance difference regions, which is the number of other regions 35 having a resistance difference R-Rn of a predetermined value or more among the plurality of other regions 35 adjacent to the region 35 to be determined, is a predetermined number or more. The determination step of determining the region 35 to be determined as the region 35 having a high tendency to precipitate lithium is included, and the determination step is performed with all the regions 35 as the determination targets. [Selection diagram] FIG. 10