Patent · US Expired

Graphite materials for negative electrode used in lithium secondary battery

US6287729A · kind A · utility

7Cited by
3References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 19, 1999
Grant dateSep 11, 2001
Priority date
Expiry dateNov 19, 2019

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02E60/10
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

There are disclosed graphite materials for a negative electrode used in a lithium secondary battery which graphite materials have an average specific surface area of 1.5 m.sup.2 /gram to 5 m.sup.2 /gram and comprise (A) milled graphite fibers which are produced by milling and graphitizing mesophase pitch-based carbon fibers, and which have an interplanar spacing of the graphite layer (d.sub.002) of at most 0.337 nm and a specific surface area of 0.8 m.sup.2 /gram to 1.3 m.sup.2 /gram; and (B) graphite materials which have an interplanar spacing of the graphite layer (d.sub.002) of at most 0.336 nm, a degree of graphitization (P.sub.101 /P.sub.100) of at least 2.0 and a specific surface area of 2 m.sup.2 /gram to 15 m.sup.2 /gram, wherein the components (A) and (B) are mixed at a ratio (A)/(B) by weight of 90/10 to 50/50. The above graphite materials comprising the components (A) and (B), when used for a negative electrode in a lithium secondary battery, can enhance the performance of the battery and charge/discharge capacity thereof especially in a high load discharge.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.