Boosting the rate performance of primary Li/CF_x batteries through interlayer conductive network engineering

As an attractive cathode material with an ultra-high theoretical capacity and energy density, graphite fluoride (CFx) is a promising option for lithium primary batteries. However, its application in high-power-demanding scenarios is limited by its poor rate performance, mainly due to its intrinsic low electrical conductivity and sluggish electrochemical kinetics. Herein, we demonstrate an innovative method that could improve the electron-transport properties and electrochemical kinetics of CFx simultaneously. This was achieved by exfoliating CFx into quasi-2D flakes and constructing conductive networks within the interlayers. The strong electronic interaction between CFx and the conductive network enabled facile charge transfer, as reflected by photoluminescence quenching and electrochemical characterization tests. This newly designed CFx cathode outperformed conventional ones in a lithium primary battery, delivering a specific capacity of 580 mA h g(-1) at a high discharge rate of 2C, which was 77% of the charge capacity at 0.1C.