OS0406-146 リチウムイオン電池内に存在する長さの異なる内部短絡の電磁場逆解析を用いた検出 : 線状短絡を模擬した試験片を用いた検証

Abstract

Lithium ion battery is generally used in mobile devices for its advantages such as easy downsizing and weight saving due to high energy density. If there is short circuit point in the battery, the abnormal heating will occur because of the high energy density. Therefore, it is necessary to identify the short circuit part in Lithium ion battery. In this study, a new technique of nondestructive detection of short circuit part has been developed by using inverse analysis of current density from the magnetic field around the battery. In the previous study, detection of the point short circuit as a micro short circuit was discussed. However, in the case of a short circuit with length such as the linear short circuit, it is thought that detection of the short circuit becomes difficult because the current density flowing into the short circuit is relatively lower and the induced magnetic flux density is also lower. In this report, the numerical and the inspection experiments were carried out using the specimen with linear short circuit. From the obtained result the effectiveness of the proposed technique and its detection limit of the short circuit length in the proposed technique were discussed.