The Safety Evaluation Test of Lithium Ion Batteries in Vehicles - Investigation of Overcharge Test Method

摘要

We conducted overcharge tests on various types of lithium-ion batteries as single cells and battery modules and compared the test results. In single cell tests, test results differed depending on the presence or absence of restraining plates, the restraining plate material, and the presence or absence of heat insulators. Furthermore, when heat dissipation was inhibitory, test results were similar to those for a battery module. A battery module is composed of stacked single cells and has more inhibitory heat dissipation than an independent single cell. Therefore, when conducting an overcharge test on a single cell, it is necessary to select the restraining plate material and restraining plate form considering the heat dissipation of an assembled battery, such as a battery module or pack, in order to simulate the restricted state in a battery module and avoid large differences in the test results for a battery module or pack.