The survey instrument of the lithium ion accumulator, in the survey instrument of the lithium

摘要

The present invention provides an inspection method for a lithium ion secondary battery in which an electrolyte and an electrode group are disposed in one container, the electrode group including a positive electrode, a negative electrode, and a separator, wherein a sensor for detecting acoustic emission is attached to the outside of the container and acoustic emission generated in the battery container is detected upon provision of charge or discharge current and stopping of provision thereof between the positive electrode and the negative electrode. Specifically, the amplitude intensity of the acoustic emission is measured that is generated upon provision of charge-discharge currents having different values, linear approximation is conducted for the charge-discharge current value and the amplitude intensity of the acoustic emission, and the number of times of charge-discharge cycles that has been provided so far to the battery is estimated.