Nonaqueous electrolyte secondary battery

Abstract

A nonaqueous electrolyte secondary battery 10 according to an embodiment of the present invention includes a positive electrode 11 having a positive electrode active material that can intercalate and deintercalate lithium, a negative electrode 12 having a negative electrode active material that can intercalate and deintercalate lithium, and a nonaqueous electrolyte having lithium ion conductivity. The positive electrode active material is a layered lithium transition metal composite oxide (for example, one represented by Li1+x(NiyCozMn1-y-z)1-xO2 (where 0≦x≦0.15, 0.1≦y≦0.6, and 0≦z≦0.5)) to which an IVa group element (Zr) and a Va group element (Nb) are added. According to these features, it is possible to provide a nonaqueous electrolyte secondary battery with a selected element to be added to the lithium transition metal composite oxide to reduce the I-V resistance (improve the I-V characteristic), and thereby improving the output/input characteristics.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described with reference to the accompanying drawing.

FIG. 1 is a sectional view schematically showing a nonaqueous electrolyte secondary battery according to an embodiment of the invention.

Claims

1. A nonaqueous electrolyte secondary battery comprising: a positive electrode including a positive electrode active material capable of intercalating and deintercalating lithium;a negative electrode including a negative electrode active material capable of intercalating and deintercalating lithium; anda nonaqueous electrolyte having lithium ion conductivity,the positive electrode active material being a layered lithium transition metal composite oxide to which an IVa group element and a Va group element are added.

2. The nonaqueous electrolyte secondary battery according to claim 1, wherein the positive electrode active material is a layered lithium transition metal composite oxide represented by Li1+x(NiyCozMn1-y-z)1-xO2, where 0≦x≦0.15, 0.1≦y≦0.6, and 0≦z≦0.5.

3. The nonaqueous electrolyte secondary battery according to claim 1, wherein the IVa group element is Zr, and the Va group element is Nb.

4. The nonaqueous electrolyte secondary battery according to claim 2, wherein the IVa group element is Zr, and the Va group element is Nb.

5. The nonaqueous electrolyte secondary battery according to claim 1, wherein the nonaqueous electrolyte contains lithium bis(oxalato)borate (Li(B(C2O4)2)).