Patent · US Expired

Method of manufacturing lithium composite oxide as positive active material for lithium secondary batteries

US6241959A · kind A · utility

30Cited by
9References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 28, 1998
Grant dateJun 5, 2001
Priority date
Expiry dateOct 28, 2018

Classification

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

Abstract

A lithium composite oxide (Li.sub.a Ni.sub.(1-x-y) Co.sub.x M.sub.y O.sub.2, where M is at least one metal atom selected from the group consisting of Al, Ca, Mg and B, a=0.97.about.1.05, x=0.1.about.0.3, and y=0.about.0.05), prepared by a method including the steps of: (a) coprecipitating a Ni--Co composite hydroxide by adding an aqueous ammonia solution as a complexing agent, and an alkaline solution as a pH-adjusting agent, to an aqueous mixed solution containing a cobalt salt and a nickel salt; (b) adding lithium hydroxide to the composite hydroxide and thermally treating the mixture at 280.about.420.degree. C.; and (c) thermally treating the resultant of the step (b) at 650.about.750.degree. C. The average particle diameter of the lithium composite oxide decreases, or the tap density thereof increases, depending on the coprecipitation time. When the lithium composite oxide is used as a positive electrode active material, a lithium ion secondary cell having a high capacity can be obtained.

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