Inspection apparatus and inspection method for lithium ion secondary battery, and secondary battery module

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.

主权项

1. An inspection apparatus for a lithium ion secondary battery in which an electrolyte and an electrode group are disposed in a container, the electrode group including a positive electrode, a negative electrode, and a separator, the inspection apparatus comprising:
a charge-discharge power supply for providing a plurality of charge and discharge currents to the lithium ion secondary battery; an AE sensor for detecting an acoustic emission generated in the container when charge current or discharge current is provided between the positive electrode and the negative electrode; and an AE analysis device for judging a state of the lithium ion secondary battery based on an amplitude intensity of the acoustic emission detected by the AE sensor; wherein the AE analysis device conducts a linear approximation for a value of the charge current or a value of the discharge current and the amplitude intensity of the acoustic emission, and estimates a number of charge-discharge cycles that have been provided to the lithium ion secondary battery.