Development of a Li ion battery safety risk assessment tool

Frequent Li-ion battery (LiB) field safety incidents on the officially approved models have caused big concerns on its safety and certification, however, little attention and study have given to the potential safety risk of the certified battery. We developed a battery safety risk assessment tool by using a modified FMEA method with the RPN concept. To validate this concept we applied the tool to the CTIA LiB safety certification program and evaluated the latent safety risk level of the approved battery models, which enable us to predict the probability of a model's safety incident in the field. To realize this idea we adopted concepts of “system integration effects” and “add additional evaluation factors” to the standard's test items. In conclusion the RPN of the each cell model shows the latent safety risk level of the battery.