Cathode materials for lithium-ion secondary cells
US6017654A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 4, 1997 |
| Grant date | Jan 25, 2000 |
| Priority date | — |
| Expiry date | Aug 4, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E60/10
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Crystalline lithiated transition metal oxide materials having a rhombohedral R-3m crystal structure includes divalent cations selected and added in amounts so that all or a portion of the divalent cations occupy sites in transition metal atom layers within the materials' crystal lattice. The lithiated transition metal oxides are useful as cathode materials in lithium-ion secondary cells. The materials include, but are not limited to, Li.sub.1+x Ni.sub.1-y M.sub.y N.sub.x O.sub.2(1+x) and Li.sub.1 Ni.sub.1-y M.sub.y N.sub.x O.sub.p, wherein M is a transition metal selected from titanium, vanadium, chromium, manganese, iron, cobalt, and aluminum, and N is a group II element selected from magnesium, calcium, strontium, barium, and zinc. The materials provide improved cyclability and high voltage capacity as cathodes in lithium-ion secondary cells. Processes for producing the divalent cation-containing lithium transition metal oxide materials of the invention are also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.