Dramatic improvement enabled by incorporating thermal conductive TiN into Si-based anodes for lithium ion batteries

Abstract

Building stable SEI film is highly desirable for high-performance Si-based anode materials used in high energy-density lithium ion batteries (LIBs), which is strongly related with the generated-heat distribution in the electrode. Herein, Si/graphene@carbon embedding with TiN nanoparticles (Si/G@C/TiN) are prepared via a facile ultrasonic spraying method. The Si/G@C/TiN delivers a reversible discharge capacity of 660 ​mAh▪g−1 ​at 10 A▪g−1 and 776.5 ​mAh▪g−1 ​at 5 A▪g−1 after 400 cycles. High electronical conductivity of TiN embedding in the porous carbon framework can not only facilitate electrons transfer in the electrode, but also improve Li-ion kenetic diffusion. High thermal conductivity of TiN would be helpful to faster heat-dissipation and uniform heat-distribution in the electrode during the charging/discharging process, resulting in balanced growth of stable SEI film and excellent cycling stability especially at elevated temperature. Moreover, Si/G@C/TiN pouch cells using LiNi0.5Co0.2Mn0.3O2 as cathode, deliver impressive energy density of ~476 ​Wh▪kg-1 based on the total weight of active materials, suggesting its promising application in the high energy-density LIBs.