Electrolyte additive and use thereof

Patent metadata

Field	Value
Publication number	US-2016233545-A1
Application number	US-201514963096-A
Country	US
Kind code	A1
Filing date	Dec 8, 2015
Priority date	Feb 6, 2015
Publication date	Aug 11, 2016
Grant date	—

Abstract

The present application discloses an electrolyte additive comprising a thiophene compound. When used in a lithium ion battery, the additive can inhibit a sustained electrochemical oxidation reaction between an electrolyte and a positive electrode material, thereby improving the electrical conductivity of the positive electrode material, enhancing the cycle performance and high-current discharge performance of the battery, and improving the safety performance and rate performance of the battery.

First claim

What is claimed is:

1 . An electrolyte additive, comprising a thiophene compound selected from at least one of a compound having a chemical structural formula as shown by Formula I and a compound having a chemical structural formula as shown by Formula II:

wherein R 10 , R 11 , R 12 , R 13 , R 20 , R 21 , R 22 , R 23 , R 24 and R 25 are respectively independently selected from hydrogen, fluoro, chloro, bromo, iodo, nitro, a sulfonic acid group, hydrocarbyl having 1-10 carbon atoms, and a group having 1-10 carbon atoms and containing at least one element selected from fluorine, chlorine, bromine, iodine, nitrogen, oxygen and sulfur.

2 . The additive according to claim 1 , wherein R 10 , R 11 , R 12 , R 13 , R 20 , R 21 , R 22 , R 23 , R 24 and R 25 are respectively independently selected from hydrogen, hydrocarbyl having 1-3 carbon atoms, and a group having 1-3 carbon atoms and containing fluorine and/or alkoxy.

3 . The additive according to claim 1 , wherein the thiophene compound is selected from at least one of 2-methyl-2,3-dihydrothieno[3,4-b][1,4]dioxane, 2-methoxymethyl-2,3-dihydrothieno[3,4-b][1,4]dioxane, 3,4-propylenedioxythiophene, 3,4-ethylenedioxythiophene, 3,4-(2,2-dimethylpropylenedioxy)thiophene and 3,4-(2,2-diethylpropylenedioxy)thiophene.

4 . The additive according to claim 1 , wherein the additive comprises a film former of a solid electrolyte interface film.

5 . The additive according to claim 4 , wherein the film former of a solid electrolyte interface film is selected from at least one of vinylene carbonate, fluoroethylene carbonate, chloroethylene carbonate, propane sultone, butane sultone and adiponitrile.

6 . An electrolyte, comprising at least one of the additives according to claim 1 .

7 . The electrolyte according to claim 6 , wherein the thiophene compound has a mass percent content of 0.1-10% in the electrolyte.

8 . The electrolyte according to claim 6 , wherein the thiophene compound has a mass percent content of 1%-8% in the electrolyte.

9 . The electrolyte according to claim 6 , wherein the film former of a solid electrolyte interface film has a mass percent content of 0.1-10% in the electrolyte.

10 . A lithium ion battery, comprising at least one of the additives according to claim 1 .

Assignees

• Ningde Amperex Technology Ltd

Inventors

• Chen Peipei
• Long Bing
• Wang Kefei

Classifications

• C07D495/04

  Ortho-condensed systems · CPC title

• H01M2220/30

  Batteries in portable systems, e.g. mobile phone, laptop · CPC title

• H01M10/0567 Primary

  characterised by the additives · CPC title

• H01M10/0525

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

• H01M2300/0025

  Organic electrolyte · CPC title