Lithium secondary battery and cathode active material therefor
AssigneeNGK Insulators, Ltd.
InventorsShohei YOKOYAMA, Nobuyuki KOBAYASHI, Tsutomu NANATAKI, Koichi KONDO, Yukinobu YURA, Kei SATO
Life of this patent
Estimating the term…
Abstract
The lithium secondary battery cathode active material having a layered rock salt structure is characterized in that the material is formed of a plurality of primary particles having a mean particle size of 0.01 to 5 μm, and contains secondary particles having a mean particle size of 1 to 100 μm and an aspect ratio, which is a ratio of long axis diameter to short axis diameter, of 1.0 or more and less than 2; and that the primary particles forming the secondary particles have a (003) plane orientation degree of 50% or higher.
Claims8
A lithium secondary battery cathode active material having a layered rock salt structure, characterized in that
- the material is formed of a large number of primary particles having a mean particle size of 0.01 to 5 μm;
- the material contains secondary particles which have a mean particle size of 1 to 100 μm and an aspect ratio, which is expressed as a value calculated by dividing a long axis diameter by a short axis diameter, of 1.0 or more and less than 2;
- and
- the primary particles forming the secondary particle have a (003) plane orientation degree of 50% or higher.
A lithium secondary battery having a cathode including a cathode active material layer and an anode including an anode active material layer, characterized in that
- the cathode active material layer contains a cathode active material in the form of secondary particles each being formed of a mass of a plurality of singe-crystal primary particles of a lithium complex oxide having a layered rock salt structure;
- the primary particles have a mean particle size of 0.01 to 5 μm;
- and
- the secondary particles have an aspect ratio, which is expressed as a value calculated by dividing a long axis diameter by a short axis diameter, of 1.0 or more and less than 2, a mean particle size of 1 to 100 μm, and a (003) plane orientation degree of 50% or higher.
Dependencies are inferred from the claim text.