Effect of groove width of modified current collector on internal short circuit of abused lithium-ion battery

Abstract

In lithium-ion battery (LIB), mechanical abuse often leads to internal short circuits (ISC) that trigger thermal runaway. We investigated a thermal-runaway mitigation (TRM) technique using modified current collector. By generating surface grooves on the current collector, the area of electrodes directly involved in ISC could be largely reduced, which decreased the ISC current. The TRM mechanism took effect immediately after the LIB was damaged. The testing data indicate that the groove width is a critical factor. With optimized groove width, this technique may enable robust and multifunctional design of LIB cells for large-scale energy-storage units.

Significance of Current Collectors for High Performance Conventional Lithium‐Ion Batteries: A Review

“…This approach has shown promising results in improving the safety performance of LIBs and minimizing the risk of accidents. [ 107 ]…”

“…The experimental results proved that this groove‐pretreated surface structure reduced heat generation and improved the safety of the battery. [ 107a,b ] In addition, they also pointed out that the electrode made of a sigmoidal‐shaped structure CC can more effectively promote the cracking of the active material and increase the impedance of the battery during battery self‐heating, and further alleviate the thermal runaway of the battery. [ 107c ]…”

“…The experimental results showed that the EPON material has an obvious thermal response phenomenon at high temperatures (>80 °C), thus destroying the conductive layer (Cu) on the SMCC surface, preventing the transmission of electrons, and improving the safety of the battery. [ 107d ]…”