Non-aqueous electrolyte secondary battery

Patent metadata

Field	Value
Publication number	US-10868299-B2
Application number	US-201716343227-A
Country	US
Kind code	B2
Filing date	Oct 19, 2017
Priority date	Oct 31, 2016
Publication date	Dec 15, 2020
Grant date	Dec 15, 2020

Abstract

The present invention relates to a non-aqueous electrolyte secondary cell comprising: a positive electrode having a positive electrode mixture layer that contains a first positive-electrode active material and a second positive-electrode active material; a negative electrode containing a lithium-titanium composite oxide as a negative-electrode active material; and a non-aqueous electrolyte. The volume per mass of pores in the first positive-electrode active material having a pore diameter of 100 nm or less is four or more times the volume per mass of pores in the second positive-electrode active material having a pore diameter of 100 nm or less. The content of the first positive-electrode active material is 30 mass % or less with respect to the total amount of the first positive-electrode active material and the second positive-electrode active material.

First claim

The invention claimed is:

1. A non-aqueous electrolyte secondary battery comprising:
a positive electrode having a positive electrode mixture layer containing a first positive electrode active material and a second positive electrode active material;
a negative electrode containing a lithium-titanium composite oxide as a negative electrode active material; and
a non-aqueous electrolyte, wherein
the first positive electrode active material has a pore volume, of pores each having a pore diameter of 100 nm or less, per mass of 8 mm 3 /g or more,
the second positive electrode active material has a pore volume, of pores each having a pore diameter of 100 nm or less, per mass of 5 mm 3 /g or less,
the pore volume, of pores each having a pore diameter of 100 nm or less, per mass of the first positive electrode active material is 4 or more times the pore volume, of pores each having a pore diameter of 100 nm or less, per mass of the second positive electrode active material, and
the content of the first positive electrode active material is 30 mass % or less based on the total amount of the first positive electrode active material and the second positive electrode active material.

2. The non-aqueous electrolyte secondary battery according to claim 1 , wherein the content of the first positive electrode active material contained in a region ranging from the surface to the center in the thickness direction of the positive electrode mixture layer is 60 mass % or more based on the total amount of the first positive electrode active material contained in the positive electrode mixture layer.

3. The non-aqueous electrolyte secondary battery according to claim 1 , wherein both the first positive electrode active material and the second positive electrode active material are lamellar lithium transition metal oxide represented by a general formula (1): Li 1+x M a O 2+b , wherein x, a, and b meet conditions: a=1, −0.2≤x≤0.4, and −0.1≤b≤0.4, and M represents a metal element including at least one element selected from the group consisting of Ni, Co, Mn, and Al.

Assignees

• Panasonic Ip Man Co Ltd

Inventors

• Baba Yasunori
• Ko Takashi
• Niina Fumiharu
• Yanagida Katsunori

Classifications

• H01M4/131 Primary

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

• H01M10/0525

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

• H01M4/505

  of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy · CPC title

• H01M4/485

  of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy (H01M4/505, H01M4/525 take precedence) · CPC title

• H01M2004/028

  Positive electrodes · CPC title