Lithium-supplementing slurry for anode, anode and lithium secondary battery

Patent metadata

Field	Value
Publication number	US-2017158903-A1
Application number	US-201615335397-A
Country	US
Kind code	A1
Filing date	Oct 26, 2016
Priority date	Dec 7, 2015
Publication date	Jun 8, 2017
Grant date	—

Abstract

The present invention provides a method of supplementing lithium for an anode used for lithium secondary battery. Particularly, the present invention relates to lithium-supplementing slurry and a method for preparing the same, as well as an anode prepared with the slurry and a lithium secondary battery including the same. In the present invention, the prepolymer is used as a binder for supplementing lithium, the process for preparing the prepolymer is easy to operate and has low cost; the lithium-supplementing method using said prepolymer is easy to operate and has low cost, and it is easy to control the amount of lithium supplemented.

First claim

What is claimed is:

1 . A lithium-supplementing slurry for an anode, comprising a lithium metal powder and a prepolymer.

2 . The slurry of claim 1 , wherein a mass of prepolymer is 5˜95% of total mass of said slurry.

3 . The slurry of claim 1 , wherein mass ratio of the lithium metal powder and prepolymer is 2:1˜1:100.

4 . The slurry of claim 1 , wherein the slurry further comprises a non-aqueous organic solvent; the mass of the non-aqueous organic solvent is 20˜89% of total mass of said slurry.

5 . The slurry of claim 4 , wherein the non-aqueous organic solvent is at least one selected from the group consisting of chain alkanes, cyclic alkanes, aromatics, chain ether, cyclic ether, ester, sulfoxide, amide, ketone, fluoroalkanes and fluoro carbonate.

6 . The slurry of claim 5 , wherein the non-aqueous organic solvent is at least one solvent selected from the group consisting of n-hexane, cyclohexane, benzene, methylbenzene, ethyl acetate, N,N-dimethyl formamide, N,N-dimethyl acetamide, dimethyl sulfoxide, tetrahydrofuran, diethyl ether, acetone, N-methylpyrrolidone, ethylene carbonate, methyl ethyl carbonate, dimethyl carbonate, fluoro n-hexane, fluoro cyclohexane, fluoro ethylene carbonate and propylene carbonate.

7 . The slurry of claim 1 , wherein the anode comprises an anode active material which is at least one material selected from a carbon based material, a tin based material and a silicon based material.

8 . The slurry of claim 7 , wherein the carbon based material is at least one selected from the group consisting of natural graphite, artificial graphite, meso-carbon microbeads, amorphous graphite, hard carbon and soft carbon.

9 . The slurry of claim 1 , wherein the average particle size of the lithium metal powder is less than 200 μm.

10 . The slurry of claim 1 , wherein the viscosity average molecular weight of the prepolymer is between 500˜100000.

11 . The slurry of claim 1 , wherein the prepolymer is synthesized from prepolymer monomer through a prepolymerization reaction.

12 . The slurry of claim 11 , wherein the prepolymer monomer is at least one selected from the group consisting of benzene alkene, alkyl acrylate, aliphatic alkene, fluorinated alkene, cyanide-containing alkene, polyurethane acrylate and epoxyalkane compounds.

13 . The slurry of claim 12 , wherein the prepolymer monomer is at least one selected from the group consisting of styrene, 4-nitrostyrene, methyl methacrylate, copolymer of methyl methacrylate and acrylonitrile, and 4-fluorostyrene.

14 . The slurry of claim 11 , wherein the reaction time of prepolymerization is between 0.1˜48 hours.

15 . The slurry of claim 11 , wherein the prepolymerization is performed at a temperature between −15˜150° C.

16 . The slurry of claim 11 , wherein an initiator is added during the prepolymerization.

17 . The slurry of claim 16 , wherein the initiator is at least one selected from the group consisting of 2-hydroxy-2-methylpropiophenone, diphenylmethanone compounds, azo compounds, preoxide compounds and redox compounds.

18 . The slurry of claim 17 , wherein the initiator is at least one selected from the group consisting of azo-bis-iso-butyronitrile (AIBN), azo-bis-isoheptonitrile, dimethyl azobisisobutyrate (AIBME), hydrogen peroxide, ammonium persulfate, potassium persulfate, sodium persulfate, benzoyl peroxide, tert-butyl benzoyl peroxide, methyl ethyl ketone peroxide and diacyl peroxide.

19 . An anode for a lithium secondary battery, wherein the slurry of claim 1 is used in the preparation of the anode.

20 . A method of preparing the anode for a lithium secondary battery of claim 19 , comprises the following steps: coating the lithium-supplementing slurry on an anode; treating the slurry coating by ultraviolet (UV) lighting or heating to carry on polymerization of prepolymer; rolling the coated anode to yield the anode used in lithium secondary battery.

21 . The method of claim 20 , wherein the reaction time of the polymerization is between 0.01˜600 seconds.

22 . The method of claim 20 , wherein the reaction temperature of the polymerization is between 0˜150° C.

23 . The method of claim 20 , wherein an initiator is added during the polymerization.

24 . The method of claim 23 , wherein the initiator is at least one selected from the group consisting of 2-hydroxy-2-methylpropiophenone, diphenylmethanone compounds, azo compounds, preoxide compounds and redox compounds.

25 . The method of claim 24 , wherein the initiator is at least one selected from the group consisting of azo-bis-isobutyronitrile (AIBN), azo-bis-isoheptonitrile, dimethyl azobisisobutyrate (AIBME), hydrogen peroxide, ammonium persulfate, potassium persulfate, sodium persulfate, benzoyl peroxide, tert-butyl benzoyl peroxide, methyl ethyl ketone peroxide and diacyl peroxide.

Assignees

• Microvast Power Systems Co Ltd

Inventors

• Mattis Wenjuan Liu
• Zang Xufeng
• Yin Jiawei

Classifications

• H01M4/386

  Silicon or alloys based on silicon · CPC title

• C08K3/08

  Metals · CPC title

• C08K2201/001

  Conductive additives · CPC title

• H01M4/134

  Electrodes based on metals, Si or alloys · CPC title

• H01M4/0435

  Rolling or calendering · CPC title