Nonaqueous electrolyte secondary battery

Patent metadata

Field	Value
Publication number	US-11764403-B2
Application number	US-201816754784-A
Country	US
Kind code	B2
Filing date	Oct 15, 2018
Priority date	Oct 16, 2017
Publication date	Sep 19, 2023
Grant date	Sep 19, 2023

Abstract

A nonaqueous electrolyte secondary battery disclosed herein includes a positive electrode plate including a positive composite layer, a negative electrode plate including a negative composite layer, and a nonaqueous electrolyte, in which the negative composite layer is composed of a facing portion facing a surface of the positive composite layer, and a non-facing portion that is on the same surface as the facing portion and does not face the surface of the positive composite layer, and the area ratio of the non-facing portion to a combined area of the facing portion and the non-facing portion of the negative composite layer is 7% or more, and the nonaqueous electrolyte contains a fluorinated carbonate and a cyclic sulfone compound.

First claim

The invention claimed is:

1. A nonaqueous electrolyte secondary battery comprising:
a power generating element configured by winding a positive electrode plate including a positive composite layer and a negative electrode plate including a negative composite layer with a separator interposed therebetween; and
a nonaqueous electrolyte containing a fluorinated carbonate, wherein
the negative composite layer comprises a facing portion facing a surface of the positive composite layer, and a non-facing portion that is on the same surface as the facing portion and does not face the surface of the positive composite layer,
the area ratio of the non-facing portion to a combined area of the facing portion and the non-facing portion of the negative composite layer is 7% or more and 13% or less,
the nonaqueous electrolyte contains a cyclic sulfone compound,
the fluorinated carbonate consists of a fluorinated cyclic carbonate, and
the cyclic sulfone compound is at least one of cyclic unsaturated sultone compounds represented by general formula (1) or cyclic sulfonic acid ester compounds represented by general formula (2):

wherein R 1 , R 2 , R 3 , R 4 and R 5 are each independently hydrogen, fluorine or a hydrocarbon group having 1 to 4 carbon atoms which may contain fluorine, and n is an integer of 1 to 3, R 6 is a group represented by formula (3), formula (4) or formula (5) and R 7 is an alkyl group having 1 to 3 carbon atoms which may contain a halogen.

2. The nonaqueous electrolyte secondary battery according to claim 1 , wherein a positive electrode potential based on lithium during charge reaches 4.4 V (vs. Li/Li + ) or more.

3. The nonaqueous electrolyte secondary battery according to claim 1 , on the surface of the non-facing portion, a peak intensity (IS) of peak due to 2p orbital of S and a peak intensity (IC) of peak due to 1s orbital of C in an X-ray photoelectron spectroscopy spectrum have a relationship of 0.05<(IS/IC).

4. The nonaqueous electrolyte secondary battery according to claim 1 , wherein the content of the fluorinated carbonate is 5% by volume or more and 30% by volume or less, based on the total amount of the nonaqueous electrolyte excluding an electrolyte salt.

5. The nonaqueous electrolyte secondary battery according to claim 1 , wherein the area ratio of the non-facing portion to a combined area of the facing portion and the non-facing portion of the negative composite layer is 7% or more and 9% or less.

6. The nonaqueous electrolyte secondary battery according to claim 1 , wherein the cyclic sulfone compound is at least one of 1,3-propene sultone or diglycol sulfate.

7. The nonaqueous electrolyte secondary battery according to claim 1 , wherein the fluorinated cyclic carbonate is monofluoroethylene carbonate.

8. The nonaqueous electrolyte secondary battery according to claim 7 , wherein the nonaqueous electrolyte further contains ethyl methyl carbonate.

Assignees

• Gs Yuasa Int Ltd

Inventors

• Kawasoe Yudai
• Nagamine Kenta
• Anami Keisuke

Classifications

• H01M10/0525 Primary

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

• H01M10/0569 Primary

  characterised by the solvents · CPC title

• H01M10/0567

  characterised by the additives · CPC title

• H01M10/0587

  of accumulators having only wound construction elements, i.e. wound positive electrodes, wound negative electrodes and wound separators · CPC title

• H01M10/0431

  Cells with wound or folded electrodes (H01M10/045 takes precedence) · CPC title