Nonaqueous electrolyte secondary battery

Patent metadata

Field	Value
Publication number	US-2021036321-A1
Application number	US-201916981753-A
Country	US
Kind code	A1
Filing date	Jan 22, 2019
Priority date	Mar 30, 2018
Publication date	Feb 4, 2021
Grant date	—

Abstract

A nonaqueous electrolyte secondary battery includes a positive electrode, a negative electrode, and a nonaqueous electrolyte. The positive electrode includes lithium composite oxide particles A and B containing Ni and Mn. The lithium composite oxide particles A include secondary particles a2 that are aggregations of primary particles a1, and contain at least one of zirconium and boron. The lithium composite oxide particles B include at least one of primary particles b1 and secondary particles b2, the primary particles b1 having a larger particle size than the primary particles a1, the secondary particles b2 being aggregations of the primary particles b1 and having a smaller particle size than the secondary particles a2. The mass ratio of the lithium composite oxide particles A to the lithium composite oxide particles B is within the range of 8:2 to 4:6.

First claim

1 . A nonaqueous electrolyte secondary battery comprising:
a positive electrode, a negative electrode, and a nonaqueous electrolyte, wherein the positive electrode includes lithium composite oxide particles A and B containing Ni and Mn, the lithium composite oxide particles A include secondary particles a2 that are aggregations of primary particles a1, and contain at least one of zirconium and boron, the lithium composite oxide particles B include at least one of primary particles b1 and secondary particles b2, the primary particles b1 having a larger particle size than the primary particles a1, the secondary particles b2 being aggregations of the primary particles b1 and having a smaller particle size than the secondary particles a2, and a mass ratio of the lithium composite oxide particles A to the lithium composite oxide particles B is within a range of 8:2 to 4:6.

2 . The nonaqueous electrolyte secondary battery according to claim 1 , wherein a Ni content is higher in the lithium composite oxide particles B than in the lithium composite oxide particles A.

3 . The nonaqueous electrolyte secondary battery according to claim 1 , wherein when the battery is stored in an environment at 60° C. for 14 days after being charged to a battery voltage of 4.3 V, an amount of Mn deposited on the negative electrode is within a range of 20 to 60 μg per gram of the negative electrode.

4 . The nonaqueous electrolyte secondary battery according to claim 1 , wherein the primary particles a1 of the lithium composite oxide particles A have an average particle size within a range of 0.3 to 0.9 μm, and the primary particles b1 of the lithium composite oxide particles B have an average particle size within a range of 3.0 to 5.0 μm.

5 . The nonaqueous electrolyte secondary battery according to claim 1 , wherein the secondary particles a2 of the lithium composite oxide particles A have an average particle size within a range of 8.0 to 17.5 μm, and the secondary particles b2 of the lithium composite oxide particles B have an average particle size within a range of 3.0 to 6.0 μm.

Assignees

• Panasonic Ip Man Co Ltd

Inventors

• Donoue Kazunori
• Watanabe Hiroki
• Miyazaki Shinya

Classifications

• H01M2004/021

  Physical characteristics, e.g. porosity, surface area · CPC title

• H01M4/525 Primary

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

• H01M2004/028

  Positive electrodes · CPC title

• H01M4/364

  as mixtures · CPC title

• H01M10/0525

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