摘要 |
The present invention relates to a negative active material for a lithium rechargeable battery and a method of preparing the same, and the negative active material prepared by coating a carbon source with a coating liquid, and drying the carbon source, and the negative active material comprises a core having a carbon source with surface-treatment layer formed on the surface of the core, the surface-treatment layer having at least one compound of coating element selected from the group cosnsisting of amorphous, semi crystalline, or crystalline hydroxides, oxyhydroxides, oxycarbonates, and hyd roxidecarbonates. The present invention provides a negative active material coated with a surface-treatment layer of a coating-element-included hydroxide, a coating-element-included oxyhydroxide, a coating-element-included oxycarbonate, or a coating-element-included hydroxycarbonate, and thereby a battery having the negative active material has less change in thickness after expansion of the active material, that is, from 12.2% to 5.3%, and furthermore, cycle-life characteristics are improved (7% or more improvement at the 200th cycle) and voltage characteristics are improved (0.04 V or more improvement at the 200th cycle).
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