The effect of the reactive milling of graphite with boron nitride, tin and antimony on lithium insertion

Boron-, tin-, and antimony-based graphite composites were studied as potential materials for negative electrodes in lithium-ion batteries. The materials were prepared by the reactive milling of mixtures of graphite (90 wt. %) with boron nitride (10 wt. %), tin (10 wt. %), or antimony (10 wt. %). Milling was performed for 2 h, 4 h, 6 h, or 8 h. The composites were characterized by X-ray diffraction and nitrogen adsorption at 77 K (BET). A gradual development of surface area during milling was observed as well as the appearance of amorphous forms. The galvanostatic characteristics of lithium insertion–deinsertion for these new composite materials were investigated. Graphite-tin composites exhibit the best reversible capacity. Modification by milling leads to a significant particle size reduction, good association of the metallic phase with graphite crystal grains, and consequently to an increase of the reversible capacity. A significant enhancement of the irreversible capacity for the composites is also observed due to the development of specific surface area. Key words: lithium-ion cell; graphite; milling; anodic material 1