Hybrid-Type Graphite Fluoride as Cathode Material in Primary Lithium Batteries
Résumé
A graphite fluoride (CF(LT)-T) series with singular physicochemical properties were prepared by a refluorination treatment between 100 and 600°C of a low-temperature (LT) fluorinated graphite. The most striking feature of these materials is the coexistence of sp2- and the sp3-type hybridizations of the carbon atoms, which gives the materials an unusual hybrid covalent/semicovalent character. This hybrid structure leads to outstanding electrochemical performances as cathode materials in primary lithium batteries. In particular a very high energy density of 2277 Wh kg–1 was achieved with the CF(LT)550 material. The discharge voltage and capacity are refluorination temperature dependent.