Positive electrode active material for non-aqueous electrolyte secondary battery, production method thereof, and non-aqueous electrolyte secondary battery using the same
A positive electrode active material for a non-aqueous electrolyte secondary battery of this invention includes: a lithium nickel composite oxide containing lithium, nickel, and at least one metal element other than lithium and nickel; and a layer containing lithium carbonate, aluminum hydroxide, and aluminum oxide, the layer being carried on the surface of the lithium nickel composite oxide. The lithium nickel composite oxide is composed such that the ratio of the nickel to the total of the nickel and the at least one metal element is 30 mol % or more. The layer is composed such that the amount of the lithium carbonate is 0.5 to 5 mol per 100 mol of the lithium nickel composite oxide. The total of aluminum atoms contained in the aluminum hydroxide and the aluminum oxide is 0.5 to 5 mol per 100 mol of the lithium nickel composite oxide.
1. A positive electrode active material for a non-aqueous electrolyte secondary battery, comprising:
a lithium nickel composite oxide containing lithium, nickel, and at least one metal element other than lithium and nickel; and
a film layer containing lithium carbonate, aluminum hydroxide, and aluminum oxide, said layer being evenly coated on the surface of said lithium nickel composite oxide,
wherein said lithium nickel composite oxide is composed such that the ratio of the nickel to the total of the nickel and said at least one metal element is 30 mol % or more,
said layer is composed such that the amount of said lithium carbonate is 0.5 to 5 mol per 100 mol of said lithium nickel composite oxide, and
the total of aluminum atoms contained in said aluminum hydroxide and said aluminum oxide is 0.5 to 5 mol per 100 mol of said lithium nickel composite oxide.
2. The positive electrode active material for a non-aqueous electrolyte secondary battery in accordance with claim 1 , wherein said lithium nickel composite oxide is represented by the general formula:
Li a Ni 1-b A b O 2
(0.98≦a≦1.1, 0.03≦b≦0.7, and A is at least one metal element selected from the group consisting of Co, Al, Ti, V, Cr, Mn, Fe and Y).
3. The positive electrode active material for a non-aqueous electrolyte secondary battery in accordance with claim 2 , wherein said lithium nickel composite oxide is represented by the general formula:
Li x Ni 1-y-z Co y M z O 2
(0.98≦x≦1.1, 0.1≦y≦0.35,
0.03≦z≦0.35, and M is at least one metal element selected from the group consisting of Al, Ti, V, Cr, Mn, Fe and Y).
4. A non-aqueous electrolyte secondary battery comprising:
a positive electrode including the positive electrode active material of claim 1 ;
a negative electrode including at least one of lithium metal, a lithium alloy and a material capable of absorbing and desorbing lithium ions; and
an electrolyte comprising a non-aqueous solvent and a lithium salt dissolved in said non-aqueous solvent.