METHOD OF CHECKING DEFECT OF LITHIUM ION SECONDARY BATTERY AND LITHIUM ION SECONDARY BATTERY MANUFACTURED BY THE SAME METHOD

摘要

The lithium ion secondary battery defect screening method according to the present invention is a method for selecting the internal micro-short defect of the lithium ion secondary battery in the aging process during the manufacturing process of the lithium ion secondary battery,After manufacturing the lithium ion secondary battery, performing primary charging and degassing; After secondary charging and discharging the lithium ion secondary battery, measuring at least one of OCV (Open Circuit Voltage) and IR (Internal Resistance) of the lithium ion secondary battery cell; a pressure aging step of aging the lithium ion secondary battery in a state in which a pressure of a certain size or more is applied; and a defect selection step of re-measuring at least one of OCV and IR of the lithium ion secondary battery cell, and then selecting a defect of the lithium ion secondary battery by comparing it with previously measured OCV and IR.