Electrolyte, electrochemical device, secondary cell, and module

Patent metadata

Field	Value
Publication number	US-9755277-B2
Application number	US-201515122812-A
Country	US
Kind code	B2
Filing date	Mar 16, 2015
Priority date	Mar 28, 2014
Publication date	Sep 5, 2017
Grant date	Sep 5, 2017

Abstract

Provided is an electrolyte solution for secondary batteries that are less likely to generate gas and excellent in high-temperature storage characteristics; an electrochemical device using the electrolyte solution; and a module using the electrochemical device. The electrolyte solution contains a solvent and an electrolyte salt, the solvent containing a fluorine-containing acyclic carbonate represented by the formula (1) and a fluorine-containing succinic anhydride represented by the formula (2). The electrolyte solution contains not less than 0.001 mass % but less than 90 vol % of the fluorine-containing acyclic carbonate, and the electrolyte solution contains 0.001 to 20 mass % of the fluorine-containing succinic anhydride.

First claim

The invention claimed is:

1. An electrolyte solution comprising a solvent and an electrolyte salt,
the solvent comprising a fluorine-containing acyclic carbonate represented by the formula (1) and a fluorine-containing succinic anhydride represented by the formula (2),
the electrolyte solution containing not less than 0.001 mass % but less than 90 vol % of the fluorine-containing acyclic carbonate,
the electrolyte solution containing 0.001 to 20 mass % of the fluorine-containing succinic anhydride, the formula (1) being:
Rf 1 OCOORf 2   (1)

wherein Rf 1 and Rf 2 are the same as or different from each other and individually represent a C1-C4 alkyl group or a C1 -C4 fluorine-containing alkyl group, but at least one of Rf 1 and Rf 2 is C1-C4 fluorine-containing alkyl group, the formula (2) being:

wherein Rf 3 to Rf 6 are the same as or different from one another and individually represent a hydrogen atom, a fluorine atom, or a C1-C10 fluorine-containing alkyl group, but not all of Rf 3 to Rf 6 are hydrogen atoms.

2. The electrolyte solution according to claim 1 ,
wherein the fluorine-containing acyclic carbonate is at least one selected from the group consisting of CF 3 CH 2 OCOOCH 2 CF 3 , CF 3 CH 2 OCOOCH 3 , and CF 3 CF 2 CH 2 OCOOCH 2 CF 2 CF 3 .

3. The electrolyte solution according to claim 1 ,
wherein the fluorine-containing succinic anhydride is at least one selected from the group consisting of compounds represented by the following formulas (3) to (5):

4. The electrolyte solution according to claim 1 ,
wherein the solvent further comprises at least one selected from the group consisting of a non-fluorinated saturated cyclic carbonate, a fluorinated saturated cyclic carbonate, and a non-fluorinated acyclic carbonate.

5. The electrolyte solution according to claim 1 ,
wherein the electrolyte salt is at least one lithium salt selected from the group consisting of LiPF 6 , LiBF 4 , LiSO 3 CF 3 , LiN(SO 2 C 3 ) 2 , LiN(SO 2 C 2 F 5 ) 2 , lithium difluoro(oxalato)borate, lithium bis(oxalato)borate, and a salt represented by LiPF a (C n F 2n+1 ) ) 6-a wherein a represents an integer of 0 to 5 and n represents an integer of 1 to 6.

6. An electrochemical device comprising the electrolyte solution according to claim 1 .

7. A secondary battery comprising the electrolyte solution according to claim 1 .

8. A module comprising the electrochemical device according to claim 6 .

Assignees

• Daikin Ind Ltd

Inventors

• Taeda Mayuko
• Yamazaki Shigeaki
• Arima Hiroyuki
• Kuwajima Yoshiko
• Miura Toshirou
• Kinoshita Shinichi
• SHIMADA Tomo

Classifications

• H01G11/62

  characterised by the solute, e.g. salts, anions or cations therein · CPC title

• Y02E60/13

  Energy storage using capacitors · CPC title

• H01M10/0569 Primary

  characterised by the solvents · CPC title

• H01G11/06

  with one of the electrodes allowing ions to be reversibly doped thereinto, e.g. lithium ion capacitors [LIC] · CPC title

• H01M10/0568

  characterised by the solutes · CPC title