Positive electrode for non-aqueous electrolyte secondary battery and non-aqueous electrolyte secondary battery using the same

Patent metadata

Field	Value
Publication number	US-9716266-B2
Application number	US-201414776270-A
Country	US
Kind code	B2
Filing date	Mar 13, 2014
Priority date	Mar 15, 2013
Publication date	Jul 25, 2017
Grant date	Jul 25, 2017

Abstract

[Object] Provided is a means for improving cycle characteristics by suppressing electrode deterioration resulting from non-uniformity of voltage across an electrode plane in a high-capacity and large-area non-aqueous electrolyte secondary battery that includes lithium nickel-based composite oxide as a positive electrode active substance.
[Solving Means] Disclosed is a positive electrode for a non-aqueous electrolyte secondary battery used in a non-aqueous electrolyte secondary battery in which the ratio value of battery area (projected area of the battery including the battery outer casing body) to rated capacity is 5 cm 2 /Ah or more and the rated capacity is 3 Ah or more, the positive electrode comprising a positive electrode current collector and a positive electrode active substance layer that is formed on a surface of the positive electrode current collector and has a positive electrode active substance containing a lithium nickel-based composite oxide and a spinel type lithium manganese composite oxide, in which, when the average secondary particle diameter (D50) of the lithium nickel-based composite oxide is D50(A) [μm], the content ratio of the lithium nickel-based composite oxide in the positive electrode active substance layer is A [% by mass], the average secondary particle diameter (D50) of the spinel type lithium manganese composite oxide is D50(B) [μm], and the content ratio of the spinel type lithium manganese composite oxide in the positive electrode active substance layer is B [% by mass], the positive electrode satisfies the following Mathematical Formula 1 and Mathematical Formula 2:
[Math. 1]

2.0< D 50( A )/ D 50( B )≦15  Mathematical Formula 1

B /( A+B )≧0.05  Mathematical Formula 2.

First claim

The invention claimed is:

1. A non-aqueous electrolyte secondary battery comprising:
a power generating element including a positive electrode, a negative electrode, and a separator, the positive electrode comprising:
a positive electrode current collector; and
a positive electrode active substance layer that is formed on a surface of the positive electrode current collector and has a positive electrode active substance containing a lithium nickel-based composite oxide and a spinel type lithium manganese composite oxide,

wherein the positive electrode satisfies the following:
2.0 <D 50( A )/ D 50( B )≦15, and

B /( A+B )≧0.05,

where an average secondary particle diameter of the lithium nickel-based composite oxide is D50(A) [μm], a content ratio of the lithium nickel-based composite oxide in the positive electrode active substance layer is A [% by mass], an average secondary particle diameter of the spinel type lithium manganese composite oxide is D50(B) [μm], and a content ratio of the spinel type lithium manganese composite oxide in the positive electrode active substance layer is B [% by mass];
wherein a ratio value of a battery area to a rated capacity of the non-aqueous electrolyte secondary battery is 5 cm 2 /Ah or more, the battery area being a projected area of the non-aqueous electrolyte secondary battery including a battery outer casing body, and the rated capacity of the non-aqueous electrolyte secondary battery is 3 Ah or more; and
wherein the spinel type lithium manganese composite oxide is LiMn 2 O 4 .

2. The non-aqueous electrolyte secondary battery according to claim 1 , wherein the lithium nickel-based composite oxide has a composition represented by a general formula Li a Ni b Mn c Co d M x O 2 ,
wherein a, b, c, d, and x satisfy the following:
0.9≦a≦1.2,

0<b<1,
0<c≦0.5,

0<d≦0.5,

0≦x≦0.3, and

b+c+d =1, and

wherein M represents at least one element selected from the group consisting of Ti, Zr, Nb, W, P, Al, Mg, V, Ca, Sr, and Cr.

3. The non-aqueous electrolyte secondary battery according to claim 2 , wherein b, c and d satisfy the following:
0.44≦b≦0.51,

0.27≦c≦0.31, and

0.19≦d≦0.26.

4. The non-aqueous electrolyte secondary battery according to claim 1 , wherein the positive electrode active substance layer has a rectangular shape and an aspect ratio of an electrode defined as a longitudinal/transversal ratio of a rectangular-shaped positive electrode active substance layer is 1 to 3.

5. The non-aqueous electrolyte secondary battery according to claim 1 , wherein the separator has a heat resistant insulating layer.

6. The non-aqueous electrolyte secondary battery according to claim 1 , wherein the non-aqueous electrolyte secondary battery is a flat stack type laminate battery in which the power generating element is enclosed in the battery outer casing body which is formed of a laminate film containing aluminum.

Assignees

• Nissan Motor

Inventors

• Ohara Kenji
• Nitta Yoshiaki
• Ichikawa Satoru
• Kano Gentaro
• Nishijima Manabu
• Shimamura Osamu
• Kawamura Fumihiro
• Hagiyama Kousuke
• Ibuka Shigeo
• Kaseda Manabu
• Suenaga Masanori
• Hirai Tamaki
• Takaya Masahiro
• Nomoto Kuniharu

Classifications

• H01M4/131

  Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx · CPC title

• H01M4/364 Primary

  as mixtures · CPC title

• H01M4/525

  of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy · CPC title

• H01M2220/20

  Batteries in motive systems, e.g. vehicle, ship, plane · CPC title

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title