Shriram et al. performed a systematic study of the internal short circuit mechanism inside a lithium-ion battery . They found short circuit between lithiated anode material and aluminum current collector, resulting in maximum heat generation.
In order to establish the internal short-circuit model of lithium-ion batteries, this paper refers to the research of Feng et al. 18, 19 introduces the internal short-circuit resistance (Rshort ) of the battery, and then couples it with the electrochemical model.
Cai et al. studied the experimental simulation of internal short circuit of lithium-ion battery polymer . They found that the risk of thermal runaway during an internal short circuit increases as the battery’s state of charge (SOC) increases.
Therefore, the severity of the internal short circuit of the lithium-ion battery can be analyzed and diagnosed by the CNN model. Table IV. Performance comparison of battery internal short circuit diagnosis model.
As a result, when the lithium-ion battery was short-circuited externally, the battery temperature rose rapidly to the maximum temperature that the battery can rise. The highest temperature caused by external short circuit appeared in the case of a single battery. The higher the SOC, the faster the battery temperature rose.
External short circuit would accelerate the rate of increase in internal resistance of lithium-ion battery. Normally, the internal resistance of the battery doubled at approximately 350 cycles. After external resistance, when number of cycle reached 170 times, internal resistance doubled.