Composite electrodes

Patent metadata

Field	Value
Publication number	US-11081692-B2
Application number	US-201515309380-A
Country	US
Kind code	B2
Filing date	May 6, 2015
Priority date	May 7, 2014
Publication date	Aug 3, 2021
Grant date	Aug 3, 2021

Abstract

The present invention pertains to an electrode-forming composition, to use of said electrode-forming composition in a process for the manufacture of a composite electrode, to said composite electrode and to a secondary battery comprising said composite electrode.

First claim

The invention claimed is:

1. An electrode-forming composition [composition (C1)] comprising:
at least one partially fluorinated fluoropolymer [polymer (F)], wherein polymer (F) is a functional partially fluorinated polymer [polymer (FF-2)] comprising recurring units derived from at least one fluorinated monomer [monomer (F)] and at least one hydrogenated monomer comprising at least one hydroxyl end group [monomer (H OH )],
at least one electro-active compound [compound (EA)],
at least one metal compound [compound (M)] of formula (V):
X 4-m AY m   (V)

wherein m is an integer from 1 to 4, A is a metal selected from the group consisting of Si, Ti and Zr, Y is a hydrolysable group and X is a hydrocarbon group, optionally comprising one or more functional groups,
an electrolyte medium comprising at least one metal salt [medium (EL)],
at least one organic solvent [solvent (S)] selected from the group consisting of alcohols, ketones, linear or cyclic esters, linear or cyclic amides and dimethyl sulfoxide, and
optionally, at least one conductive agent [compound (C);
wherein at least one of the metal compounds (M) is grafted to polymer (FF-2) by at least one of the hydroxyl end groups of the hydrogenated monomer (H OH ) through at least one —O-A bond.

2. The composition (C1) according to claim 1 , wherein the polymer (F) is selected from the group consisting of:
polymers (F-1) comprising recurring units derived from vinylidene fluoride (VDF) and, optionally, at least one fluorinated monomer [monomer (F)] different from VDF, and
polymers (F-2) comprising recurring units derived from at least one per(halo)fluorinated monomer [monomer (FX)] selected from tetrafluoroethylene (TFE) and chlorotrifluoroethylene (CTFE), at least one hydrogenated monomer [monomer (H)] selected from ethylene, propylene and isobutylene and, optionally, at least one monomer (F) different from said monomer (FX).

3. The composition (C1) according to claim 1 , wherein the compound is of formula (VI):
R A 4-m′ A(OR B ) m′   (VI)

wherein m′ is an integer from 1 to 4, A is a metal selected from the group consisting of Si, Ti and Zr, R A and R B , equal to or different from each other and at each occurrence, are independently selected from C 1 -C 18 hydrocarbon groups, optionally comprising one or more functional groups.

4. The composition (C1) according to claim 1 , wherein the compound is either a non-functional compound (M) or a functional compound (M).

5. The composition (C1) according to claim 1 , wherein the medium (EL) comprises the at least one metal salt and at least one organic carbonate.

6. The composition (C1) according to claim 1 , wherein the medium (EL) comprises the at least one metal salt, at least one ionic liquid and, optionally, at least one organic carbonate.

7. A process for the manufacture of a composite electrode [electrode (CE)], said process comprising:
(i) providing an electrode [electrode (E)] comprising:
a metal substrate and
directly adhered onto one surface of said metal substrate, at least one layer [layer (L1)] made from a composition comprising at least one functional partially fluorinated fluoropolymer [polymer (FF)], at least one electro-active compound [compound (EA)] and, optionally, at least one conductive agent [compound (C)];

(ii) providing the electrode-forming composition [composition (C1)] according to claim 1 ;
(iii) applying the composition (C1) provided in step (ii) onto the surface of the electrode (E) provided in step (i) thereby providing a surface-coated electrode; and
(iv) drying the surface-coated electrode provided in step (iii).

8. The process according to claim 7 , wherein the electrode [electrode (E)] is obtainable by:
(j) providing a metal substrate;
(jj) applying onto one surface of the metal substrate provided in step (j) an electrode-forming composition [composition (C2)] comprising:
at least one functional partially fluorinated fluoropolymer [polymer (FF)],
at least one electro-active compound [compound (EA)],
at least one organic solvent [solvent (S)] and
optionally, at least one conductive agent [compound (C)]
thereby providing a surface-coated electrode; and

(jjj) drying the surface-coated electrode provided in step (jj).

9. The process according to claim 8 , wherein the composition (C2) is free from an electrolyte medium comprising at least one metal salt [medium (EL)].

10. The process according to claim 7 , wherein the polymer (FF) is a functional partially fluorinated fluoropolymer [polymer (FF-1)] comprising recurring units derived from vinylidene fluoride (VDF), at least one hydrogenated monomer comprising at least one functional end group [monomer (HF)], said monomer (HF) comprising at least one functional end group selected from a hydroxyl end group and a carboxylic acid end group, and, optionally, at least one monomer (F) different from VDF.

11. The process according to claim 10 , wherein the monomer (HF) is of formula (III-A):

wherein R′1, R′2 and R′3 are hydrogen atoms and R″X is a hydrogen atom or a C1-C5 hydrocarbon group comprising at least one hydroxyl group.

12. A composite electrode [electrode (CE)] obtained by the process according to claim 7 .

13. The electrode (CE) according to claim 12 , comprising:
a metal substrate,
directly adhered onto one surface of said metal substrate, at least one layer [layer (L1)] made from a composition comprising at least one functional partially fluorinated fluoropolymer [polymer (FF)], at least one electro-active compound [compound (EA)] and, optionally, at least one conductive agent [compound (C)] and
directly adhered to said layer (L1), at least one layer [layer (L2)] made from a composition comprising at least one partially fluorinated fluoropolymer [polymer (F)], at least one electro-active compound [compound (EA)], an electrolyte medium comprising at least one metal salt [medium (EL)] and, optionally, at least one conductive agent [compound (C)].

14. A secondary battery comprising:
a positive electrode,
a negative electrode and
between said positive electrode and negative electrode, a membrane,
wherein at least one of the positive electrode and the negative electrode is the composite electrode [electrode (CE)] according to claim 12 .

Assignees

• Solvay
• Commissariat A L Energie Atomique Et Aux Energies Alternatives
• Commissariat a energie atomique et aux energies alternatives

Inventors

• Pras Olivier
• Rouault Helene
• Abusleme Julio A

Classifications

• H01M4/13

  Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof · CPC title

• H01M4/133

  Electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx · CPC title

• Y02P70/50

  Manufacturing or production processes characterised by the final manufactured product · CPC title

• H01M4/661

  Metal or alloys, e.g. alloy coatings (H01M4/669 take precedence) · CPC title

• H01M10/052

  Li-accumulators · CPC title