Composite carbon material of negative electrode in lithium ion battery and its preparation method
US8993170B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 29, 2006 |
| Grant date | Mar 31, 2015 |
| Priority date | — |
| Expiry date | Feb 28, 2028 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E60/10
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A composite carbon material of negative electrode in lithium ion, which is made of composite graphite, includes a spherical graphite and a cover layer, wherein the cover layer is pyrolytic carbon of organic substance. Inserted transition metal elements are contained between layers of graphite crystal. Preparation of the negative electrode includes the steps of: crushing graphite, shaping to form a spherical shape, purifying treatment, washing, dewatering and drying, dipped in salt solution doped by transition metal in multivalence, mixed with organic matter, covering treatment, and carbonizing treatment or graphitization treatment. The negative electrode provides advantages of reversible specific capacity larger than 350 mAh/g, coulomb efficiency higher than 94% at first cycle, conservation rate for capacity larger than 8-% in 500 times of circulation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.