Cathode electroactive material, production method therefor and secondary cell
US6699618B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 20, 2001 |
| Grant date | Mar 2, 2004 |
| Priority date | — |
| Expiry date | Jan 20, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E60/10
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A cathode electroactive material for use in lithium ion secondary cells, process for producing the material, and lithium ion secondary cells using the cathode electroactive material, wherein the electroactive material predominantly comprises an Li—Mn composite oxide particles with the spinel structure and particles of the electroactive material have an average porosity of 15% or less, the porosity being calculated by employing the following equation:Porosity (%)=(A/B)×100  (1)(wherein A represents a total cross-section area of pores included in a cross-section of one secondary particle, and B represents the cross-section area of one secondary particle), a tapping density of 1.9 g/ml or more, a size of crystallites of 400 å-960 å, a lattice constant of 8.240 å or less.The cathode electroactive material of the present invention is formed of particles which are dense and spherical and exhibit excellent packing characteristics to an electrode, and exhibit high initial capacity and capacity retention percentage at high temperature.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.