Negative active material for rechargeable lithium battery, method of preparing same, and rechargeable lithium battery including same
AssigneeSamsung SDI Co., Ltd.
InventorsDoori OH, Chul YOUM
Life of this patent
Estimating the term…
Abstract
A negative active material for a rechargeable lithium battery includes a silicon-carbon composite including a core including a crystalline carbon material, a silicon oxide, and a silicon particle and an amorphous carbon-containing coating layer on the surface of the core. An intensity ratio (Si/SiO2) of a Si peak relative to a SiO2 peak ranges from about 2.0 to about 3.0 as measured using an X-ray photoelectron spectroscopy for the negative active material.
Claims11
A negative active material for a rechargeable lithium battery, the negative active material comprising:
- a silicon-carbon composite including a core including a crystalline carbon material, a silicon oxide, and a silicon particle, and an amorphous carbon-containing coating layer on the surface of the core,
- wherein an intensity ratio (Si/SiO2) of a Si peak relative to a SiO2 peak ranges from about 2.0 to about 3.0 as measured using an X-ray photoelectron spectroscopy for the negative active material.
A method of preparing a negative active material for a rechargeable lithium battery, the method comprising:
- mixing silicon and the antioxidant in a mixing ratio of about 9 wt % to about 11 wt % of an antioxidant relative to 100 wt % of silicon in a solvent to prepare a mixture;
- ball milling the mixture to prepare a silicon mixture of a silicon oxide and a silicon particle coated with the antioxidant;
- mixing the silicon mixture with a crystalline carbon-based material to prepare a silicon-crystalline carbon-based material mixture;
- adding an amorphous carbon precursor to the silicon-crystalline carbon-based material mixture, and
- heat-treating the resultant.
Dependencies are inferred from the claim text.