METHOD FOR ANALYZING LITHIUM ION CONCENTRATION DISTRIBUTION IN LITHIUM ION SECONDARY BATTERY ELECTRODE AND CELL FOR EVALUATION

摘要

To provide an analyzing method by which in analyzing a lithium ion secondary battery under a low-temperature environment where a lithium ion concentration distribution in an electrode becomes conspicuous, a length of time until a temperature in the lithium ion secondary battery reaches the same temperature as that of the low-temperature environment can be shortened, and the lithium ion secondary battery can be evaluated rapidly.SOLUTION: A method for analyzing a lithium ion concentration distribution in an electrode of a lithium ion secondary battery comprises the steps of: charging/discharging a lithium ion secondary battery including an electrode, an electrolyte and a constraint plate at a temperature of -30 to -10°C; and a particular step. In the method, the constraint plate applies an external pressure to the lithium ion secondary battery; the constraint plate is 0.0003 K/W or less in heat resistance at 300K; a surface of the constraint plate is covered with an insulator of a volume resistivity of 10Ωcm or more; and the insulator does not react with the electrolyte during the charging/discharging step.SELECTED DRAWING: Figure 2