Abstract
Forming an ultrathin conducting layer on a fluorinated carbon(CFx)surface for reducing severe elec-trochemical polarization in lithium/fluorinated carbon pri-mary batteries(Li/CFx)remains a considerable challenge for achieving batteries with excellent rate capability.Herein,CFx was modified by using acetylene/argon mix-ture plasma combined with MnO2 particles.The CFx/C/MnO2 composite effectively reduced the voltage hysteresis and improved the electrochemical performance of Li/CFx.The excellent rate performance of CFx/C/MnO2 was due to the high electrochemical activity provided by the atomic-scale conductive carbon layer and ultrafine MnO2 particles.Compared with pristine CFx,the charge transfer resistance of the optimized CFx/C/MnO2 decreased from 218.5 to 48.2 Ω,the discharge rate increased from 2C to 10C,and the power density increased from 3.11 to 13.44 kW·g-1.The intrinsic reason for the enhanced rate performance was attributed to the fact that the ultrathin carbon layer acted as a conductive bridge to reduce the voltage hysteresis at the initial stage of the Li/CFx discharge,and the high electro-chemical activity of the ultrafine MnO2 particles provided a faster lithium-ion diffusion rate.
基金项目
国家自然科学基金(51972045)
中央高校基本科研业务费专项(ZYGX2019J025)
NETL
NSTL
万方数据