Patent · US Active

Cathode active material for lithium secondary battery

US7935444B2 · kind B2 · utility

6Cited by
5References
22Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 23, 2009
Grant dateMay 3, 2011
Priority date
Expiry dateOct 28, 2029

Classification

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

Abstract

Disclosed herein is a cathode active material for a lithium secondary battery, in particular, including a lithium transition metal oxide with a layered crystalline structure in which the transition metal includes a transition metal mixture of Ni, Mn and Co, and an average oxidation number of all transition metals other than lithium is more than +3, and specific conditions represented by the following formulae (1) and (2), 1.1<m(Ni)/m(Mn)<1.5 and 0.4<m(Ni2+)/m(Mn4+)<1, are satisfied. The inventive cathode active material has a more uniform and stable layered structure by controlling the oxidation number of transition metals contained in a transition metal oxide layer to form the layered structure, compared to conventional substances. Accordingly, the active material exhibits improved overall electrochemical characteristics including battery capacity and, in particular, excellent high rate charge-discharge features.

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