Nonaqueous electrolyte secondary battery

Patent metadata

Field	Value
Publication number	US-9640798-B2
Application number	US-201314434317-A
Country	US
Kind code	B2
Filing date	Oct 25, 2013
Priority date	Oct 30, 2012
Publication date	May 2, 2017
Grant date	May 2, 2017

Abstract

A nonaqueous electrolyte secondary battery according to one aspect of the present invention contains a dispersant in a positive electrode mixture layer. The content of a positive electrode active material in the positive electrode mixture layer is 97% by mass or more, and the content ratio of a conductive agent to a binder in the positive electrode mixture layer is 1.00-1.67. The binder is composed of a polyvinylidene fluoride which has a carboxyl group or a carboxyl group derivative as a terminal functional group.

First claim

The invention claimed is:

1. A nonaqueous electrolyte secondary battery comprising:
a positive electrode plate having a positive electrode mixture layer formed thereon, the positive electrode mixture layer containing a positive electrode active material which stores and releases a lithium ion, a conductive agent, a binder, and a dispersant,
a negative electrode plate having a negative electrode mixture layer formed thereon, the negative electrode mixture layer containing a negative electrode active material which stores and releases a lithium ion,

a nonaqueous electrolyte solution, and
a separator;
the dispersant being selected from the group consisting of methyl cellulose, hydroxyethyl methyl cellulose, hydroxypropyl methyl cellulose, and polyvinyl propanol, a content of the positive electrode active material in the positive electrode mixture layer being from 97% by mass or more to 98.25% by mass;
a content ratio of the conductive agent to the binder in the positive electrode mixture layer being 1.00-1.67; and
the binder being composed of a polyvinylidene fluoride having, as a terminal functional group, one selected from the group consisting of a carboxyl group and a carboxyl group derivative.

Assignees

• Sanyo Electric Co

Inventors

• Maekawa Masanori
• Iwami Yasunobu
• Kinoshita Akira

Classifications

• H01M4/62

  Selection of inactive substances as ingredients for active masses, e.g. binders, fillers · CPC title

• H01M4/623 Primary

  fluorinated polymers · CPC title

• Y02T10/7011

  Cross-Sectional Technologies · mapped topic

• Y02E60/122

  Cross-Sectional Technologies · mapped topic

• H01M4/625

  Carbon or graphite · CPC title