Positive electrode material for non-aqueous electrolyte lithium ion battery and battery using the same
A positive electrode material for non-aqueous electrolyte lithium ion battery ( 31, 41 ) of the present invention has an oxide ( 11 ) containing lithium and nickel, and a lithium compound ( 13 ) which is deposited on a surface of the oxide ( 11 ) and covers nickel present on the surface of the oxide ( 11 ). By this structure, it is possible to suppress decomposition of an electrolysis solution as much as possible and drastically reduce swelling of the batteries ( 31, 41 ).
1. A positive electrode material for non-aqueous electrolyte lithium ion battery, comprising:
an oxide containing lithium and nickel; and
a lithium compound deposited on a surface of the oxide,
wherein the lithium compound is lithium sulfate.
2. A positive electrode material according to claim 1 , wherein the lithium compound is deposited to cover substantially an entire surface of the oxide, and a thickness of a cover layer of the lithium compound ranges from 5 nm to 1 μm.
3. A positive electrode material according to claim 1 , wherein the lithium compound is deposited to sprinkle on the surface of the oxide, and a volume of the lithium compound ranges from 0.5 to 10% with respect to a volume of the positive electrode active material.
4. A non-aqueous electrolyte lithium ion battery, comprising:
a positive electrode active material layer comprising a positive electrode material according to claim 1 ;
a negative electrode active material layer comprising a negative electrode active material; and
an electrolyte layer disposed between the positive and negative electrode active materials layers.