Carbon monofluorides derived from sponge and shot cokes

Abstract.

Carbon fluoride compounds, CF _x , are used as cathode materials in commercially important primary Li/CF _x electrochemical power sources. New CF _x compounds were prepared, apparently for the first time, from sponge and shot cokes by direct fluorination. The carbon starting materials and CF _x products were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, and elemental analysis for total fluorine. The discharge capacity of shot coke CF _x was unexpectedly low and is probably related to the heterogeneous nature of that form of coke. CF _x prepared from sponge coke that had been heated to 1930 °C exhibited the highest capacity, exceeding the capacity of a commercially available, battery grade CF _x . The discharge results show that CF _x from heated sponge coke has favorable electrochemical properties that render it attractive for lithium electrochemical power sources.