Novel Silica -Coated Cathode to Realize Internal-Short-circuit Proof, High-Interface-stabilized, High-Safety Lithium Batteries

Lithium-Ion Batteries (LIBs) are currently used in more and more places where safety and reliability are necessary. To protect LIBs from short-circuiting, extend their life, and improve their safety, we propose a novel SiO2-nanoparticle-coated cathode. The coating can prevent short-circuiting of the lithium-ion battery when the separator fails. The SiO2 nanoparticles form a coating with high porosity, good electrolyte compatibility, and increased interfacial stability of the cathode material. In this way, the coating reduces the internal resistance of the cell to a certain extent, thus improving cycle performance and Coulombic efficiency. The thermal safety performance of the assembled pouch batteries is investigated. The results show that the pouch cell assembled with a protective layer of cathode prolongs the occurrence time of thermal runaway, reduces the amount of heat released by thermal runaway, and improves batteries safety.