Composition comprising a fluorinated polymer bearing polar groups and a polymer additive comprising phosphorus atoms and binder for electrodes for a li-ion battery

Abstract

The present invention relates to a composition comprising a fluorinated polymer bearing polar groups P1 and a polymer additive P2 comprising at least one functional group containing a phosphorus atom, and to the use thereof as a binder for electrodes for a Li-ion battery.

Description

[0001] COMPOSITION COMPRISING A FLUORINATED POLYMER CARRYING POLAR GROUPS AND A POLYMER ADDITIVE COMPRISING PHOSPHORUS ATOMS AND BINDER FOR ELECTRODES FOR LI-ION BATTERIES

[0002] Technical field

[0003] The present invention relates generally to the field of electrical energy storage in rechargeable secondary batteries of the Li-ion type. More specifically, the present invention relates to a composition comprising a fluoropolymer and an additive. The composition can be used as a binder to the electrode.

[0004] Technological background of the invention

[0005] In recent years, there have been remarkable developments in electronic technology, and the functionality of miniature mobile devices has become increasingly advanced, creating a demand for smaller and lighter power supplies (to have higher energy density) for use in such devices. As high energy density batteries, non-aqueous electrolyte secondary batteries such as lithium-ion secondary batteries are widely used.

[0006] An electrode for lithium-ion secondary batteries can be obtained, for example, by the following means: First, a formulation is obtained by mixing powdery electrode materials such as an electrode active material and a conductive agent, which can be added if necessary, with a binder and dissolving or dispersing the mixed material in a suitable solvent. Subsequently, an electrode for lithium-ion secondary batteries can be obtained by covering a current collector with the obtained electrode mixture slurry, evaporating the solvent.

[0007] The active materials used in electrodes are generally nickel-based and more specifically contain a majority of nickel. However, when the ratio of nickel in the active material of the electrode increases, the electrode mixture slurry becomes prone to gelation. For example, document EP3795430 is known, which describes an electrode composition comprising a vinylidene fluoride-based polymer comprising a polar group and at least 10% of an acrylic polymer. However, it has been observed that the electrode composition is much too viscous (above 40,000 cP initially) to be implemented on an industrial scale. Also known from document EP2147029 is a copolymer between vinylidene fluoride and acrylic acid which has a strong tendency to sediment over time.Generally speaking, an electrode composition must be industrially processable, stable (not sediment) and not gel over time. There is therefore always a need for electrode compositions with a good compromise between the different properties. The present invention aims to solve all or part of the disadvantages of current electrode compositions by providing a particular polymer composition.

[0008] Summary of the invention

[0009] According to a first aspect, the present invention relates to a composition comprising a fluorinated polymer carrying polar groups PI and a polymer additive P2 comprising repeating units derived from a monomer M2 of formula (I), (II), (III), (IV), (V), (VI), (VII) or a mixture thereof R 1 R 2 C=C(R 3 )((X 2 )pC(O)R 4 ) (I) R 5 R 6 C=C(R 7 )(OC(O)R 8 ) (II)

[0010] R 9 R 10 C=CR 11 C(O)OC(O)CR 12 =CR 13 R 14 (lll)

[0011] R 30 R 31 C=CR 32 (CN) (VI)

[0012] R 33 R 34 C=CR 35 (C(O)NR 36 R 37 ) (VII) in which

[0013] R 1 , R 2 and R 3 are independently of each other selected from the group consisting of H, CO2H and C1-C5 alkyl;

[0014] R 4 is selected from the group consisting of -NHC CHshCI-hC OjCHs and -OR 25 with R 25 selected from the group consisting of H and Ci-Cis alkyl optionally substituted with one or more group(s) selected from the group consisting of -OH, -CO2H, SO3H, - OPO3 2- , -C(O)OR 25 , -OC(O)R 25, and a five- or six-membered heterocycle comprising at least one nitrogen atom in its ring chain;

[0015] R 25 is selected from the group consisting of C1-C5 alkyl and Cg-Cu aryl substituted with one or more CO2H functional groups;

[0016] X 2 is selected from the group consisting of -[-C(O)OC(R 26 )(R 27 )C(R 28 )(R 29 )-] W I- and a C1-C10 alkyl hydrocarbon group optionally carrying one or more -OH, -CO2H or ester group(s); with wl being an integer from 1 to 50, advantageously from 1 to 25, preferably from 1 to 10, in particular from 1 to 5; R 26 , R 27 , R 28 , R 29 are independently of each other, independently for each wl unit, selected from the group consisting of H and C1-C5 alkyl; p' is 0 or 1;

[0017] R 5 , R 6 and R 7are independently of each other selected from the group consisting of H and C1-C5 alkyl;

[0018] R 8 is C1-C5 alkyl;

[0019] R 9 , R 10 , R 11 , R 12 , R 13 , R 14 , R 15 , R 16 , R 17 , R 18 , R 19 , R 20 , R 21 , R 22 , R 23 , R 24 , R 30 , R 31 , R 32 , R 33 , R 34 , R 35 are independently of each other selected from the group consisting of H and C1-C5 alkyl, preferably selected from the group consisting of H and CH3;

[0020] R 36 and R 37 are, independently of each other, selected from the group consisting of H and C1-C10 alkyl optionally substituted by one or more group(s) -OH, -CO2H, SO3H, -OPO3 2 -C(O)OR 38 , -OC(O)R 38 ; R38 is selected from the group consisting of C1-C5 alkyl and C6-C12 aryl substituted by one or more CO2H functional groups; characterized in that said polymer additive P2 also comprises at least one functional group containing a phosphorus atom.

[0021] The applicant surprisingly found that the specific composition according to the present invention exhibited a very good compromise between the various properties required for its use in applications such as electrode compositions. The composition has an ideal viscosity to be industrially processable, does not sediment over time and does not gel over time.

[0022] According to a preferred embodiment, the phosphorus content in said polymer additive P2 is between 0.01 and 15 mol% per mol of polymer additive P2.

[0023] According to a preferred embodiment, the functional group containing a phosphorus atom is selected from the group consisting of -P(O)(OX + )-, -P(O)(OX + )2 and -P(O)(O _ X + )H with X selected from the group consisting of H, Na, Li and K.

[0024] According to a preferred embodiment, the mass ratio between said fluorinated polymer PI and said polymer additive P2 is greater than or equal to 1, advantageously greater than or equal to 5, preferably greater than or equal to 10, more preferably greater than or equal to 15, in particular greater than or equal to 20.

[0025] According to a preferred embodiment, the mass ratio between said fluoropolymer PI and said polymer additive P2 is less than or equal to 1000, preferably less than or equal to 400. According to a preferred embodiment, said polymer PI comprises repeating units derived from a monomer Mla selected from the group consisting of vinyl fluoride; vinylidene fluoride (VDF); trifluoroethylene (TrFE); chlorotrifluoroethylene (CTFE); 1,2-difluoroethylene; tetrafluoroethylene (TFE); hexafluoropropylene (HFP); perfluoro(alkyl vinyl) ethers such as perfluoro(methyl vinyl) ether (PMVE), perfluoro(ethyl vinyl) ether (PEVE) and perfluoro(propyl vinyl) ether (PPVE); perfluoro(1,3-dioxole); perfluoro(2,2-dimethyl-1,3-dioxole) (PDD); the product of formula CF2=CFOCF2CF(CF3)OCF2CF2X in which X is SO2F, CO2H, CH2OH, CH2OCN or CH2OPC>3H; the product of formula CF2=CFOCF2CF2SO2F; the product of formula F(CF2)nCH2OCF=CF2in which n is 1, 2, 3, 4 or 5; the product of formula R1 CH2OCF=CF2in which R 1 is hydrogen or F(CF2)m and m is 1, 2, 3 or 4; the product of formula R 2 OCF=CH2in which R 2 is F(CF2)p and p is 1, 2, 3 or 4; perfluorobutylethylene (PFBE); trifluoropropene, tetrafluoropropene, hexafluoroisobutylene, perfluorobutylethylene, pentafluoropropene, bromotrifluoroethylene, chlorofluoroethylene, chlorotrifluoropropene and 2-trifluoromethyl-3,3,3-trifluoro-l-propene or a mixture thereof.

[0026] According to a preferred embodiment, said fluoropolymer PI comprises repeating units derived from the monomer Mla and repeating units derived from a monomer Mlc and optionally repeating units derived from a monomer Mlb; said monomer Mla being vinylidene fluoride; said monomer Mlb selected from the group consisting of vinyl fluoride; trifluoroethylene (TrFE); chlorotrifluoroethylene (CTFE); 1,2-difluoroethylene; tetrafluoroethylene (TFE); hexafluoropropylene (HFP); perfluoro(alkyl vinyl) ethers such as perfluoro(methyl vinyl) ether (PMVE), perfluoro(ethyl vinyl) ether (PEVE) and perfluoro(propyl vinyl) ether (PPVE); perfluoro(1,3-dioxole); perfluoro(2,2-dimethyl-1,3-dioxole) (PDD); the product of formula CF2=CFOCF2CF(CF3)OCF2CF2X in which X is SO2F, CO2H, CH2OH, CH2OCN OR CH2OPO3H; the product of formula CF2=CFOCF2CF2SO2F; the product of formula F(CF2)nCH2OCF=CF2in which n is 1, 2, 3, 4 or 5; the product of formula R 1CH2OCF=CF2in which R 1 is hydrogen or F(CF2)m and m is 1, 2, 3 or 4; the product of formula R 2 OCF=CH2in which R 2 is F(CF2)p and p is 1, 2, 3 or 4; perfluorobutyl ethylene (PFBE); trifluoropropene, tetrafluoropropene, hexafluoroisobutylene, perfluorobutylethylene, pentafluoropropene, bromotrifluoroethylene, chlorofluoroethylene, chlorotrifluoropropene and 2-trifluoromethyl-3,3,3-trifluoro-l-propene or a mixture thereof; said monomer Mlc being selected from the group consisting of formula R a R b C=C(R c )((X 3 ) P "HORN d ) in which the substituents R a , R b and R c are independently of each other selected from the group consisting of H, CO2H and C1-C5alkyl; R d is selected from the group consisting of -NHC(CH3hCH2C(O)CH3 or -OR d ' with R d' selected from the group consisting of H and Ci- Ci8 alkyl optionally substituted by one or more group(s) -OH, -CO2H, -SO3H, - PO3H, -OC(O)R d ", -C(O)OR d " or a five- or ten-membered heterocycle comprising at least one nitrogen atom in its ring chain; R d " being selected from the group consisting of C1-C8 alkyl or C1-C12 aryl optionally substituted by one or more group(s) -OH, -CO2H, -SO3H, -PO3H; p" is 0 or 1; X 3 is selected from the group consisting of -[- C(O)OC(R 26 ')(R 27 ')C(R 28 ')(R 29 ')-]W2- and a C1-C10 alkyl hydrocarbon group optionally carrying one or more -OH, -CO2H or ester group(s); with w2 being an integer from 1 to 50, advantageously from 1 to 25, preferably from 1 to 10, in particular from 1 to 5; R 26 ', R 27 ', R 28 ', R 29are independently of each other, independently for each w2 unit, selected from the group consisting of H and C1-C5 alkyl.

[0027] According to a preferred embodiment, said Mlc monomer is present in said PI polymer in a molar content of 0.01% to 5%.

[0028] According to a preferred embodiment, said monomer Mlb is present in said polymer PI in a molar content of 1% to 25%.

[0029] According to a preferred embodiment, said polymer additive P2 has a molar mass by weight of between 500 g / mol and 50000 g / mol, preferably between 500 g / mol and 25000 g / mol.

[0030] According to a preferred embodiment, said polymer additive P2 comprises repeating units derived from a monomer M2 of formula (I), (III) or (IV) which

[0031] R 1 , R 2 and R 3are independently of each other selected from the group consisting of H, CO2H and C1-C3 alkyl;

[0032] R 4 is -OR 25 with R 25 selected from the group consisting of H and C1-C15 alkyl optionally substituted with one or more group(s) selected from the group consisting of -OH, -CO2H, SO3H, -OPO3 2 -C(O)OR 25 , -OC(O)R 25 , and a five- or six-membered heterocycle comprising at least one nitrogen atom in its ring chain;

[0033] R 25 is selected from the group consisting of C1-C5 alkyl and Cg-Ci2 aryl substituted with one or more CO2H functional groups;

[0034] X 2 is selected from the group consisting of -[-C(O)OC(R 26 )(R 27 )C(R 28 )(R 29 )-] WI- and a C1-C10 alkyl hydrocarbon group optionally carrying one or more -OH, -CO2H or ester group(s); with wl being an integer from 1 to 50, advantageously from 1 to 25, preferably from 1 to 10, in particular from 1 to 5; R 26 , R 27 , R 28 , R 29 are independently of each other, independently for each wl unit, selected from the group consisting of H and C1-C5 alkyl; p' is 0 or 1;

[0035] R 9 , R 10 , R 11 , R 12 , R 13 , R 14 , R 15 , R 16 are independently of each other selected from the group consisting of H and C1-C5 alkyl, preferably selected from the group consisting of H and CH3.

[0036] According to a preferred embodiment, said polymer additive P2 comprises repeating units derived from a monomer M2 of formula (I), (III) or (IV) in which R 1 , R 2and R 3 are independently of each other selected from the group consisting of H, CO2H and C1-C3alkyl;

[0037] R 4 is -OR 25 with R 25 selected from the group consisting of H and C1-C10 alkyl optionally substituted with one or more group(s) selected from the group consisting of -OH, -CO2H, SO3H, -OPO3 2 -C(O)OR 25 , -OC(O)R 25 , and a five- or six-membered heterocycle comprising at least one nitrogen atom in its ring chain;

[0038] R 25 is selected from the group consisting of C1-C5 alkyl and Cg aryl substituted with one or more CO2H functional groups;

[0039] X 2 is selected from the group consisting of -[-C(O)OC(R 26 )(R 27 )C(R 28 )(R 29 )-] WI- and a C1-C5 alkyl hydrocarbon group optionally carrying one or more -OH, -CO2H or ester group(s); with wl being an integer from 1 to 5; R 26 , R 27 , R 28 , R 29 are independently of each other, independently for each wl unit, selected from the group consisting of H and C1-C5 alkyl; p' is 0 or 1;

[0040] R 9 , R 10 , R 11 , R 12 , R 13 , R 14 , R 15 , R 16 are independently of each other selected from the group consisting of H and C1-C5 alkyl, preferably selected from the group consisting of H and CH3.

[0041] According to a preferred embodiment, said composition has a sedimentation factor S of between 0.8 and 1.1; calculated according to the protocol detailed in the present application.

[0042] According to another aspect, the present invention provides a binder for a Li-ion battery comprising said composition according to the present invention.

[0043] According to another aspect, the present invention provides an electrode composition comprising an active material and said binder according to the preceding claim.

[0044] According to another aspect, the present invention provides an electrode for a lithium-ion battery comprising a metal collector at least one face of which is coated with said electrode composition according to the present invention. According to another aspect, the present invention provides a Li-ion secondary battery comprising an anode, a cathode and a separator, wherein the anode or the cathode is an electrode according to the present invention.

[0045] Detailed Description of the Present Invention

[0046] According to a first aspect of the present invention, a composition is provided. Said composition may be in powder form or in the form of a latex or a solution in the presence of an organic solvent. Preferably, said composition is in powder form. Said composition comprises a fluoropolymer PI and a polymer additive P2 which are detailed below. According to a particular embodiment, said composition consists of a fluoropolymer PI and a polymer additive P2 which are detailed below. Said polymer PI carries polar groups.

[0047] In said composition, the mass ratio between said fluoropolymer PI and said polymer additive P2 is greater than or equal to 1, advantageously greater than or equal to 5, preferably greater than or equal to 10, more preferably greater than or equal to 15. Advantageously, the mass ratio between said fluoropolymer PI and said polymer additive P2 is greater than or equal to 20, advantageously greater than or equal to 21, preferably greater than or equal to 22, more preferably greater than or equal to 23, in particular greater than or equal to 24, more particularly greater than or equal to 25, preferably greater than or equal to 26. The mass ratio refers to the ratio of the mass contents in the composition of the two compounds considered.Preferably, the mass ratio between said fluorinated polymer PI and said polymer additive P2 is greater than or equal to T1, advantageously greater than or equal to 28, preferably greater than or equal to 29, more preferably greater than or equal to 30, in particular greater than or equal to 31, more particularly greater than or equal to 32, preferably greater than or equal to 33, advantageously greater than or equal to 34, preferably greater than or equal to 35, more preferably greater than or equal to 36, particularly preferably greater than or equal to 37, more particularly preferably greater than or equal to 38.

[0048] The content of polymer additive P2 in said composition influences the viscosity in the electrode composition with which it is prepared. Thus, it has been found that when the ratio between the fluoropolymer PI and the polymer additive P2 is less than 19, the viscosity of the electrode composition is too high to be processable on an industrial scale. Advantageously, in said composition, the mass ratio between said fluoropolymer PI and said polymer additive P2 is less than or equal to 1000, preferably less than or equal to 900, more preferably less than or equal to 800, in particular less than or equal to 700, more particularly less than or equal to 600, preferably less than or equal to 500, advantageously preferably less than or equal to 400.

[0049] According to a particular embodiment, in said composition, the mass ratio between said fluoropolymer PI and said polymer additive P2 is less than or equal to 375, preferably less than or equal to 350, more preferably less than or equal to 325, in particular less than or equal to 300, more particularly less than or equal to 275, preferably less than or equal to 250, advantageously less than or equal to 225, preferably less than or equal to 200. It has been found that when the mass ratio between the fluoropolymer PI and the polymer additive P2 is too high, the electrode composition prepared with said composition sediments over time. Thus, in order to improve the stability of the electrode composition over time and thus avoid sedimentation thereof, it is preferable to have a mass ratio P1 / P2 as expressed above.

[0050] According to a particular embodiment, when said composition is in powder form, it comprises at least 95% by weight of said fluoropolymer PI based on the total weight of the composition, advantageously at least 96% by weight, preferably at least 97% by weight, more preferably at least 98% by weight, in particular at least 98.5% by weight of said fluoropolymer PI based on the total weight of the composition.

[0051] According to a particular embodiment, when said composition is in powder form, it comprises less than 5% by weight, advantageously less than 4% by weight, preferably less than 3% by weight, more preferably less than 2% by weight, in particular less than 1.5% by weight, of said polymer additive P2 based on the total weight of the composition.

[0052] According to a particular embodiment, when said composition is in powder form, it consists of from 0.01% to 5%, advantageously from 0.05% to 4%, preferably from 0.1% to 3%, more preferably from 0.5% to 2.5%, in particular from 0.5 to 2.0%, more particularly from 0.75 to 1.5% by weight of said polymer additive P2 based on the total weight of said composition; the remainder being said fluoropolymer PI.

[0053] Said composition may be prepared by mixing the constituents, for example in powder form, in the required proportions. Alternatively, the constituents may be mixed in the form of an aqueous solution or an organic solution (i.e. in the presence of an organic solvent), in the required proportions and then the solution may be dried to obtain a powder or used as such. Said organic solvent is not specifically limited and is chosen so as to solubilize said fluoropolymer PI and said polymer additive P2.Ledit solvant organique peut être de manière non limitative n-methylpyrrolidone (NMP), dimethylsulfoxide (DMSO), N,N-dimethylformamide (DMF), triethylphosphite (TEP), acétone, cyclopentanone, tetrahydrofurane, methyl ethylketone (MEK), methyl isobutyl ketone (MiBK), ethyl acetate (EA), butyl acetate (BA), ethylene carbonate (EC), propylene carbonate (PC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), gamma-butyrolactone and N-butylpyrrolidone ; et les mélanges de ceux-ci.

[0054] According to a preferred embodiment, the ratio between the viscosity V2 and the viscosity VI is between 0.25 and 5.0; the viscosity V2 corresponds to the viscosity obtained from the composition according to the present invention and the viscosity VI corresponds to the viscosity obtained from the fluoropolymer PI. Advantageously, said ratio V2 / V1 is between 0.5 and 4.5, preferably between 0.75 and 4.0, more preferably between 0.75 and 3.5, in particular between 0.75 and 3.0, more particularly between 0.75 and 2.5. Said viscosities VI and V2 are measured according to the protocol described below in the examples. When the ratio V2 / V1 is in the range mentioned above, the electrode composition comprising the composition according to the invention has very good rheological behavior to facilitate the processability thereof during the preparation of an electrode.

[0055] According to a preferred embodiment, the sedimentation factor S of said composition according to the invention is between 0.8 and 1.1, advantageously between 0.82 and 1.05, preferably between 0.84 and 1.05, more preferably between 0.86 and 1, in particular between 0.88 and 1, more particularly between 0.90 and 1. The sedimentation factor S corresponds to the ratio between the solid content of a composition at t = 0 and the solid content of a composition at t = 120h. The sedimentation factor is calculated according to the protocol detailed below in the examples. Said composition according to the present invention makes it possible to avoid sedimentation of the electrode composition comprising it. To ensure good implementation of an electrode, it is preferable for the sedimentation factor S to remain within the range mentioned above.More particularly, thanks to the composition according to the present invention, the sedimentation factor S is between 0.95 and 1, advantageously between 0.96 and 1, preferably between 0.97 and 1, more preferably between 0.98 and 1. The stability over time, that is to say the absence of sedimentation, makes it possible to guarantee homogeneity of the electrode composition during the preparation of an electrode, which improves the quality and performance thereof. The composition according to the present invention makes it possible to achieve this objective.

[0056] Fluorinated polymer PI

[0057] According to a preferred embodiment, said fluoropolymer PI comprises in its chain at least one fluoromonomer Mla chosen from compounds containing a vinyl group capable of opening to polymerize and which contains, directly attached to this vinyl group, at least one fluorine atom, a fluoroalkyl group or a fluoroalkoxy group. As mentioned above, said fluoropolymer PI carries polar groups. These polar groups may be present in said fluoropolymer PI via a monomer carrying said polar groups. Alternatively, said polar groups may be grafted onto a fluoropolymer to give said fluoropolymer PI according to known techniques.Preferably, the polar groups are introduced into said fluorinated polymer PI via a monomer carrying said polar groups, for example via the Mlc monomers as described below in the present application.

[0058] Preferably, said fluoropolymer PI comprises repeating units derived from a monomer Mla selected from the group consisting of vinyl fluoride; vinylidene fluoride (VDF); trifluoroethylene (TrFE); chlorotrifluoroethylene (CTFE); 1,2-difluoroethylene; tetrafluoroethylene (TFE); hexafluoropropylene (HFP); perfluoro(alkyl vinyl) ethers such as perfluoro(methyl vinyl) ether (PMVE), perfluoro(ethyl vinyl) ether (PEVE) and perfluoro(propyl vinyl) ether (PPVE); perfluoro(1,3-dioxole); perfluoro(2,2-dimethyl-1,3-dioxole) (PDD); the product of formula CF2=CFOCF2CF(CF3)OCF2CF2X in which X is SO2F, CO2H, CH2OH, CH2OCN or CH2OPC>3H; the product of formula CF2=CFOCF2CF2SO2F; the product of formula F(CF2)nCH2OCF=CF2in which n is 1, 2, 3, 4 or 5; the product of formula R 1 CH2OCF=CF2in which R 1 is hydrogen or F(CF2)m and m is 1, 2, 3 or 4; the product of formula R 2 OCF=CH2in which R 2is F(CF2)p and p is 1, 2, 3 or 4; perfluorobutylethylene (PFBE); trifluoropropene, tetrafluoropropene, hexafluoroisobutylene, perfluorobutylethylene, pentafluoropropene, bromotrifluoroethylene, chlorofluoroethylene, chlorotrifluoropropene and 2-trifluoromethyl-

[0059] 3.3.3-trifluoro-l-propene or a mixture thereof. Among the trifluoropropenes we can cite

[0060] 3,3,3-trifluoropropene. Among the tetrafluoropropenes, we can cite 2, 3,3,3-tetrafluoropropene, 1,3,3,3-tetrafluoropropene. Among the pentafluoropropenes, we can cite

[0061] 1.1.3.3.3-pentafluoropropene or 1,2,3,3,3-pentafluoropropene. Chlorofluoroethylene may refer to either 1-chloro-1-fluoroethylene or 1-chloro-2-fluoroethylene. The 1-chloro-1-fluoroethylene isomer is preferred. Chlorotrifluoropropene is preferably 1-chloro-3,3,3-trifluoropropene or 2-chloro-3,3,3-trifluoropropene.

[0062] In particular, said fluoropolymer PI comprises at least repeating units derived from a monomer Mla being vinylidene fluoride. The fluoropolymer PI is preferably a copolymer of vinylidene fluoride.

[0063] According to another particular embodiment, the fluoropolymer PI is a polymer comprising repeating units derived from a monomer Mla being vinylidene fluoride and repeating units derived from a monomer Mlc and optionally repeating units derived from a fluoromonomer Mlb. In said fluoropolymer PI, the mass content of repeating units Mla is at least 50%, preferably at least 60%, more preferably greater than 70% and advantageously greater than 80%.

[0064] According to another embodiment, said fluorinated polymer PI comprises repeating units derived from a monomer Mla being vinylidene fluoride and repeating units derived from a monomer Mlc.

[0065] In this case, said monomer Mlc may be of formula R a R b C=C(R c )((X 3 ) P "HORN d ) in which the substituents R a , R b and R c are independently of each other selected from the group consisting of H, CO2H and C1-C5 alkyl; R d is selected from the group consisting of - NHC(CH3hCH2C(O)CH3 or -OR d ' with R d ' selected from the group consisting of H and Ci-Cis alkyl optionally substituted by one or more group(s) -OH, -CO2H, -SO3H, -PO3H, -OC(O)R d ", -C(O)OR d " or a five- or ten-membered heterocycle comprising at least one nitrogen atom in its ring chain; R d " being selected from the group consisting of C1-C8 alkyl or C6-C12 aryl optionally substituted by one or more -OH, -CO2H, -SO3H, -PO3H group(s); p" is 0 or 1; X 3is selected from the group consisting of -[- C(O)OC(R 26 ')(R 27 ')C(R 28 ')(R 29 ')-]W2- and a C1-C10 alkyl hydrocarbon group optionally carrying one or more -OH, -CO2H or ester group(s); with w2 being an integer from 1 to 50, advantageously from 1 to 25, preferably from 1 to 10, in particular from 1 to 5; R 26 ', R 27 ', R 28 ', R 29are independently of each other, independently for each w2 unit, selected from the group consisting of H and C1-C5 alkyl. Said heterocycle may be saturated or unsaturated or aromatic. Said heterocycle may be monocyclic or bicyclic. Said heterocycle may be a pyrrole, pyrrolidine, pyridine, piperidine, pyrimidine, pyrazine, 1,4-dihydropyridine, indole, oxindole, isatin, quinoline, isoquinoline, quinazoline, imidazoline, pyrazolidine, 2-pyrrolidone, deltalactam, succinimide, 2-imidazolidinone, 4-imidazolidinone ring. Said heterocycle may be substituted by one or more C1-C5 alkyl groups. As mentioned above, the C1-C5 alkyl is optionally substituted by said heterocycle. The latter can be linked to the alkyl chain by the nitrogen atom or any other atom forming the heterocycle. Preferably the heterocycle is 2-pyrrolidone, delta-lactam, succinimide, 2-imidazolidinone, 4-imidazolidinone.

[0066] Advantageously, said monomer Mlc may be of formula R a R b C=C(R c )((X 3 ) P "HORN d ) in which the substituents R a , R b and R c are independently of each other selected from the group consisting of H, CO2H and C1-C5 alkyl; R d is -OR d ' with R d ' selected from the group consisting of H and Ci-Cis alkyl optionally substituted by one or more group(s) - OH, -CO2H, -SO3H, -PO3H, -OC(O)R d ", -C(O)OR d " or a five- or ten-membered heterocycle comprising at least one nitrogen atom in its ring chain; R d " being selected from the group consisting of C1-C8 alkyl or C1-C12 aryl optionally substituted by one or more group(s) -OH, -CO2H, -SO3H, -PO3H; p" is 0 or 1; X 3 is selected from the group consisting of -[-C(O)OC(R 26 ')(R 27 ')C(R28 ')(R 29 ')-] W 2- and a C1-C10 alkyl hydrocarbon group optionally carrying one or more -OH, -CO2H or ester group(s); with w2 being an integer from 1 to 50, advantageously from 1 to 25, preferably from 1 to 10, in particular from 1 to 5; R 26 ', R 27 ', R 28 ', R 29 ' are independently of each other, independently for each w2 unit, selected from the group consisting of H and C1-C5 alkyl.

[0067] Preferably, said monomer Mlc may be of formula R a R b C=C(R c )((X 3 ) P "HORN d ) in which the substituents R a , R b and R c are independently of each other selected from the group consisting of H, CO2H and C1-C5 alkyl; R d is -OR d ' with R d' selected from the group consisting of H and C1-C15 alkyl optionally substituted with one or more group(s) - OH, -CO2H, -SO3H, -PO3H, -OC(O)R d ", -C(O)OR d "; R d "being selected from the group consisting of C1-C5 alkyl or Cg-Cio aryl optionally substituted by one or more group(s) -OH, -CO2H, -SO3H, -PO3H; p" is 0 or 1; X 3 is selected from the group consisting of -[-C(O)OC(R 26 ')(R 27 ')C(R 28 ')(R 29 ')-] W 2- and a C1-C10 alkyl hydrocarbon group optionally carrying one or more -OH, -CO2H or ester group(s); with w2 being an integer from 1 to 50, advantageously from 1 to 25, preferably from 1 to 10, in particular from 1 to 5; R 26 ', R 27 ', R 28 ', R 29 ' are independently of each other, independently for each w2 unit, selected from the group consisting of H and C1-C5 alkyl.

[0068] More preferably, said monomer Mlc may be of formula R a R b C=C(R c )((X 3 ) P "HORN d ) in which the substituents R a , R b and R c are independently of each other selected from the group consisting of H, CO2H and C1-C3 alkyl; R d is -OR d ' with R d ' selected from the group consisting of H and C1-C10 alkyl optionally substituted with one or more group(s) -OH, -CO2H, -SO3H, -PO3H, -OC(O)R d ", -C(O)OR d "; R d " being selected from the group consisting of C1-C5 alkyl or Cg aryl optionally substituted by one or more group(s) -OH, -CO2H, -SO3H, -PO3H; p" is 0 or 1; X 3 is selected from the group consisting of -[-C(O)OC(R 26 ')(R 27 ')C(R 28 ')(R 29 ')-] W2- and a C1-C5 alkyl hydrocarbon group optionally carrying one or more -OH, -CO2H or ester group(s); with w2 being an integer from 1 to 5; R 26 ', R 27 ', R 28 ', R 29 ' are independently of each other, independently for each w2 unit, selected from the group consisting of H and C1-C3 alkyl.

[0069] In particular, said monomer Mlc may be of formula R a R b C=C(R c )(HORN d ) in which the substituents R a , R b and R c are independently of each other selected from the group consisting of H, CO2H and C1-C3 alkyl; R d is -OR d ' with R d ' selected from the group consisting of H and C1-C10 alkyl optionally substituted with one or more group(s) - OH, -CO2H, -SO3H, -PO3H, -OC(O)R d ", -C(O)OR d "; R d" being selected from the group consisting of C1-C5 alkyl or Cg aryl optionally substituted by one or more group(s) -OH, -CO2H, -SO3H, -PO3H.

[0070] Said monomer Mlc may also be of formula R e R f C=C(R g )(OC(O)R h ) ; R i R j C=CR k C(O)OC(O)CR l =CR m R n ; R°R p C=CR q (CN); R r R s C=CR'(C(O)NR u R v ) ; in which

[0071] R h is C1-C5 alkyl;

[0072] R e , R f , R g , R h , R 1 , R j , R k , R 1 , R m , R n , R°, R p , R q , R r , R s , R', R u , R vare independently of each other selected from the group consisting of H and C1-C5 alkyl, preferably selected from the group consisting of H and CH3.

[0073] Said Mlc monomer may also be of formula in which R aa , R ab , R ac , R ad , R ae , R af , R ag , R ah , R ai , R aj , R ak , R al are independently of each other selected from the group consisting of H and C1-C5 alkyl, preferably selected from the group consisting of H and CH3.

[0074] According to a particularly preferred embodiment, said monomer Mlc may be acrylic acid, methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, isobutyl acrylate, t-butyl acrylate, n-dodecyl acrylate, amyl acrylate, isoamyl acrylate, hexyl acrylate, 2-ethylhexyl acrylate, diacetone acrylamide, lauryl acrylate, n-octyl acrylate, hydroxypropyl methacrylate, hydroxybutyl methacrylate, hydroxyethyl methacrylate, hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxybutyl acrylate, methacrylic acid (or methylacrylic acid or methyl acrylic acid), methyl methacrylate, methacrylate ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, t-butyl methacrylate, n-dodecyl methacrylate, amyl methacrylate, isoamyl methacrylate, hexyl methacrylate,2-ethylhexyl methacrylate, lauryl methacrylate, n-octyl methacrylate, ureido methacrylate, maleic anhydride, vinyl acetate, acrylamide, acrylonitrile, methacrylic anhydride of formula CH2=C(CH3)C(O)OC(O)C(CH3)=CH2, monomers of formula CH2=CH(CO2CH2CH2CO2H), CH2=CH(CO2CH2CH2-OC(O)-CH2CH2CO2H), CH2=CH(CO2CH2CH2CH2-OC(O)-CH2CH2CO2H), CH2=CH(CO2CH(CH3)CH2-OC(O)-CH2CH2CO2H),CH2=CH(CO2CH2CH2-OC(O)-C6H4CO2H), CH2=CH(CO2CH2CH2CH2CH(CO2H)CH2CH2CO2H); and mixtures thereof. Among these, said Mlc monomer with an alkyl group having from 1 to 8 carbon atoms is preferred, and an alkyl group having from 1 to 5 carbon atoms is more preferable. Said fluoropolymer PI may comprise one or more repeating units derived from said Mlc monomer as defined herein. Preferably, when containing, said polymer PI comprises from 0.01% to 10%, preferably from 0.05% to 5%, in particular from 0,1% to 5% by mole of repeating units derived from said Mlc monomer based on said PI polymer.,

[0075] Preferably, when the fluorinated monomer Mla is vinylidene fluoride, the molar content of vinylidene fluoride repeating units in said fluorinated polymer PI is at least 50%, preferably at least 60%, more preferably at least 70%, in particular at least 80%, more particularly at least 90%, preferably at least 95%.

[0076] In particular, said fluorinated polymer PI comprises at least 50%, preferably at least 60%, more preferably at least 70%, in particular at least 80%, more particularly at least 90%, preferably at least 95% by mole of repeating units derived from a monomer Mla being vinylidene fluoride and from 0.01% to 5% by mole of repeating units derived from a monomer Mlc as defined above, based on said polymer PI; in particular said monomer Mlc is selected from the group consisting of acrylic acid, methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, isobutyl acrylate, t-butyl acrylate, n-dodecyl acrylate, amyl acrylate, isoamyl acrylate, hexyl acrylate, 2-ethylhexyl acrylate, diacetone acrylamide, lauryl acrylate, n-octyl acrylate, hydroxypropyl methacrylate, hydroxybutyl methacrylate, hydroxyethyl methacrylate, hydroxyethyl acrylate,hydroxypropyl acrylate, hydroxybutyl acrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, t-butyl methacrylate, n-dodecyl methacrylate, amyl methacrylate, isoamyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate, n-octyl methacrylate, ureido methacrylate, maleic anhydride, vinyl acetate, acrylamide, acrylonitrile, methacrylic anhydride of formula CH2=C(CH3)C(O)OC(O)C(CH3)=CH2, monomers of formula CH2=CH(CO2CH2CH2CO2H), CH2=CH(CO2CH2CH2-OC(O)-CH2CH2CO2H), CH2=CH(CO2CH2CH2CH2-OC(O)-CH2CH2CO2H), CH2=CH(CO2CH(CH3)CH2-OC(O)-CH2CH2CO2H),CH2=CH(CO2CH2CH2-OC(O)-C6H4CO2H), CH2=CH(CO2CH2CH2CH2CH(CO2H)CH2CH2CO2H); and mixtures thereof.,

[0077] Optionally, said fluorinated polymer PI also comprises repeating units derived from a fluorinated monomer Mlb. Said fluorinated monomer Mlb is different from the monomer Mla. Preferably, said fluorinated monomer Mlb is selected from the group consisting of vinyl fluoride; trifluoroethylene (TrFE); chlorotrifluoroethylene (CTFE); 1,2-difluoroethylene; tetrafluoroethylene (TFE); hexafluoropropylene (HFP); perfluoro(alkyl vinyl) ethers such as perfluoro(methyl vinyl) ether (PMVE), perfluoro(ethyl vinyl) ether (PEVE) and perfluoro(propyl vinyl) ether (PPVE); perfluoro(1,3-dioxole); perfluoro(2,2-dimethyl-1,3-dioxole) (PDD); the product of formula CF2=CFOCF2CF(CF3)OCF2CF2X in which X is SO2F, CO2H, CH2OH, CH2OCN or CH2OPO3H; the product of formula CF2=CFOCF2CF2SC>2F; the product of formula F(CF2)nCH2OCF=CF2 in which n is 1, 2, 3, 4 or 5; the product of formula R 1 CH2OCF=CF2 in which R 1is hydrogen or F(CF2)m and m is 1, 2, 3 or 4; the product of formula R 2 OCF=CH2 in which R 2is F(CF2)p and p is 1, 2, 3 or 4; perfluorobutyl ethylene (PFBE); trifluoropropene, tetrafluoropropene, hexafluoroisobutylene, perfluorobutylethylene, pentafluoropropene, bromotrifluoroethylene, chlorofluoroethylene, chlorotrifluoropropene and 2-trifluoromethyl-3,3,3-trifluoro-1-propene or a mixture thereof. Preferably, the fluoropolymer PI comprises repeating units derived from a monomer Mla being vinylidene fluoride and repeating units derived from a fluorinated monomer Mlb selected from the group consisting of vinyl fluoride; trifluoroethylene; chlorotrifluoroethylene; 1,2-difluoroethylene, tetrafluoroethylene; hexafluoropropylene; perfluoro(alkyl vinyl)ethers such as perfluoro(methyl vinyl)ether, perfluoro(ethyl vinyl)ether or perfluoro(propyl vinyl)ether; perfluoro(l,3-dioxole); perfluoro(2,2-dimethyl-l,3-dioxole); the product of formula CF2=CFOCF2CF(CF3)OCF2CF2X in which X is SO2F, CO2H, CH2OH,CH2OCN or CH2OPO3H; the product of formula CF2=CFOCF2CF2SO2F; the product of formula F(CF2)nCH2OCF=CF2in which n is 1, 2, 3, 4 or 5; the product of formula R'CH2OCF=CF2in which R' is hydrogen or F(CF2)Z and z is 1, 2, 3 or 4; the product of formula R"OCF=CH2in which R" is F(CF2)z and z is 1, 2, 3 or 4; trifluoropropene, tetrafluoropropene, hexafluoroisobutylene, perfluorobutylethylene, pentafluoropropene, bromotrifluoroethylene, chlorofluoroethylene, chlorotrifluoropropene or 2-trifluoromethyl-3,3,3-trifluoro-1-propene or a mixture thereof. In particular, the fluoropolymer PI comprises repeating units derived from a monomer Mla being vinylidene fluoride and repeating units derived from a fluorinated monomer Mlb selected from the group consisting of trifluoroethylene, chlorotrifluoroethylene, 1,2-difluoroethylene, tetrafluoroethylene and hexafluoropropylene or a mixture thereof. Preferably, when it contains them,said fluorinated polymer PI comprises from 1% to 40%, preferably from 1% to 30%, more preferably from 1% to 25%, in particular from 2 to 20%, more particularly from 1 to 10% by mole of repeating units derived from said monomer Mlb based on said polymer PI. The molar or mass contents of repeating units derived from the monomer Mla, Mlb or Mlc is determined by NMR, 1 H and / or 19 F.

[0078] According to another embodiment, said fluoropolymer PI comprises repeating units derived from a monomer Mla being vinylidene fluoride, repeating units derived from a fluoropolymer Mlb, repeating units derived from a monomer Mlc; said monomers Mlb and Mlc being as defined above in the proportions as defined above. According to a preferred embodiment, said fluoropolymer PI is prepared by a suspension or emulsion polymerization process forming a latex which can optionally be dried to result in a fluoropolymer PI in powder form.

[0079] According to one embodiment, the average particle size of said PI polymer is between 10 and 1000 nm. According to another embodiment, the average particle size is between 1 pm and 200 pm, preferably between 1 pm and 100 pm. The average particle size is determined by laser granulometry. A particle size analyzer of the Malvern INSITEC System type is used for the measurement. This is carried out in a dry process by laser diffraction on a powder with a focal length of 100 mm.

[0080] According to certain embodiments, the vinylidene fluoride contained in said PI fluoropolymer is bio-sourced. The term "bio-sourced" means "derived from biomass". This makes it possible to improve the ecological footprint of the polymer. The bio-sourced VDF can be characterized by a renewable carbon content, i.e. carbon of natural origin and originating from a biomaterial or biomass, of at least 1 atomic % as determined by the 14C content according to standard NF EN 16640. The term "renewable carbon" indicates that the carbon is of natural origin and originates from a biomaterial (or biomass), as indicated below.According to certain embodiments, the bio-carbon content of the VDF may be greater than 5%, preferably greater than 10%, preferably greater than 25%, preferably greater than or equal to 33%, preferably greater than 50%, preferably greater than or equal to 66%, preferably greater than 75%, preferably greater than 90%, preferably greater than 95%, preferably greater than 98%, preferably greater than 99%, advantageously equal to 100%.

[0081] Polymer additive P2

[0082] As mentioned above, said composition comprises a polymer additive P2.

[0083] Said polymer additive P2 comprises at least one functional group containing a phosphorus atom.

[0084] Preferably, the phosphorus content in said polymer additive P2 is between 0.01 and 15 mol% per mol of polymer additive P2. Thus, the phosphorus content may be between 0.05 mol% and 14 mol%, advantageously between 0.1 mol% and 13 mol%, preferably between 0.25 mol% and 12 mol%, more preferably between 0.5 mol% and 11 mol%, in particular between 0.75 mol% and 10 mol%, more particularly between 1 mol% and 10 mol% per mol of polymer additive P2.

[0085] Said functional group containing a phosphorus atom may be selected from the group consisting of -P(O)(OX + )-, -P(O)(OX + )2 and -P(O)(OX + )H with X selected from the group consisting of H, Na, Li and K. Said functional group containing a phosphorus atom may be located at the end of chains or along the chain of said polymer P2.

[0086] The applicant surprisingly found that the presence of at least one functional group containing a phosphorus atom in the polymer additive P2 improved the viscosity of an electrode composition while preventing sedimentation thereof. The viscosity improvement is characterized by a lower viscosity facilitating the processability of an electrode composition compared to a polymer additive not containing a functional group with a phosphorus atom.

[0087] The polymer additive P2 also comprises repeating units derived from a monomer M2 of formula (I), (II), (III), (IV), (V), (VI), (VII) or a mixture thereof R 1 R 2 C=C(R 3 )((X 2 ) P -HORN 4 ) (I) R 5 R 6 C=C(R 7 )(OC(O)R 8 ) (II)

[0088] R 9 R 10 C=CR 11 C(O)OC(O)CR 12 =CR 13 R 14 (lll)

[0089] R 30 R 31 C=CR 32 (CN) (VI)

[0090] R 33 R 34 C=CR 35 (C(O)NR 36 R 37 ) (VII) in which

[0091] R 1 , R 2 and R 3 are independently of each other selected from the group consisting of H, CO2H and C1-C5 alkyl;

[0092] R 4 is selected from the group consisting of -NHC(CH3hCH2C(O)CH3 and -OR 25 with R 25 selected from the group consisting of H and Ci-Cis alkyl optionally substituted with one or more group(s) selected from the group consisting of -OH, -CO2H, SO3H, - OPO3 2 -C(O)OR 25 ' , -OC(O)R 25 ' , and a five- or six-membered heterocycle comprising at least one nitrogen atom in its ring chain;

[0093] R 25is selected from the group consisting of C1-C5 alkyl and Cg-Ci2 aryl substituted with one or more CO2H functional groups;

[0094] X 2 is selected from the group consisting of -[-C(O)OC(R 26 )(R 27 )C(R 28 )(R 29 )-] W I- and a C1-C10 alkyl hydrocarbon group optionally carrying one or more -OH, -CO2H or ester group(s); with wl being an integer from 1 to 50, advantageously from 1 to 25, preferably from 1 to 10, in particular from 1 to 5; R 26 , R 27 , R 28 , R 29 are independently of each other, independently for each wl unit, selected from the group consisting of H and C1-C5 alkyl; p' is 0 or 1;

[0095] R 5 , R 6 and R 7 are independently of each other selected from the group consisting of H and C1-C5 alkyl;

[0096] R 8 is C1-C5 alkyl;

[0097] R 9 , R 10 , R 11 , R 12 , R 13 , R 14 , R 15 , R 16 , R 17 , R 18 , R 19 , R 20 , R 21 , R 22 , R 23 , R 24 , R 30 , R 31 , R 32 , R 33 , R 34 , R 35 are independently of each other selected from the group consisting of H and C1-C5 alkyl, preferably selected from the group consisting of H and CH3; R 36 and R 37 are, independently of each other, selected from the group consisting of H and C1-C10 alkyl optionally substituted by one or more group(s) -OH, -CO2H, SO3H, -OPO3 2 -C(O)OR 38 , -OC(O)R 38 ; R 38 is selected from the group consisting of C1-C5 alkyl and

[0098] C6-Ci2 aryl substituted by one or more CO2H functional groups.

[0099] Advantageously, the polymer additive P2 comprises repeating units derived from a monomer

[0100] M2 of formula (I), (II), (III), (IV), (V) or a mixture thereof

[0101] R 1 R 2 C=C(R 3 )((X 2 )pC(O)R 4 ) (I)

[0102] R 5 R 6 C=C(R 7 )(OC(O)R 8 ) (II)

[0103] R 9 R 10 C=CR 11 C(O)OC(O)CR 12 =CR 13 R 14 (lll)

[0104] R 30 R 31 C=CR 32 (CN) (VI)

[0105] R 33 R 34 C=CR 35 (C(O)NR 36 R 37 ) (VII) in which

[0106] R 1 , R 2 and R 3 are independently of each other selected from the group consisting of H, CO2H and C1-C5 alkyl;

[0107] R 4is selected from the group consisting of -NHC CHshCI-hC OjCHs and -OR 25 with R 25 selected from the group consisting of H and C1-C15 alkyl optionally substituted with one or more group(s) selected from the group consisting of -OH, -CO2H, SO3H, - OPO3 2- , -C(O)OR 25 , -OC(O)R 25 , and a five- or six-membered heterocycle comprising at least one nitrogen atom in its ring chain;

[0108] R 25 is selected from the group consisting of C1-C5 alkyl and Cg-Cu aryl substituted with one or more CO2H functional groups;

[0109] X 2 is selected from the group consisting of -[-C(O)OC(R 26 )(R 27 )C(R 28 )(R 29 )-] W I- and a C1-C10 alkyl hydrocarbon group optionally carrying one or more -OH, -CO2H or ester group(s); with wl being an integer from 1 to 10, in particular from 1 to 5; R26 , R 27 , R 28 , R 29 are independently of each other, independently for each wl unit, selected from the group consisting of H and C1-C5 alkyl; p' is 0 or 1; R 5 , R 6 and R 7 are independently of each other selected from the group consisting of H and C1-C3 alkyl;

[0110] R 8 is C1-C3 alkyl;

[0111] R 9 , R 10 , R 11 , R 12 , R 13 , R 14 , R 15 , R 16 , R 17 , R 18 , R 19 , R 20 , R 21 , R 22 , R 23 , R 24 , R 30 , R 31 , R 32 , R 33 , R 34 , R 35 are independently of each other selected from the group consisting of H and C1-C3 alkyl, preferably selected from the group consisting of H and CH3;

[0112] R36 and R 37 are, independently of each other, selected from the group consisting of H and C1-C5 alkyl optionally substituted by one or more group(s) -OH, -CO2H, SO3H, -OPO3 2 -C(O)OR 38 , -OC(O)R 38 ; R 38 is selected from the group consisting of C1-C3 alkyl and Cg aryl substituted with one or more CO2H functional groups.

[0113] Preferably, said polymer additive P2 comprising repeating units derived from a monomer M2 of formula (I), (II), (III) (IV), (V), (VI), (VII) or a mixture thereof R 1 R 2 C=C(R 3 )((X 2 ) P -HORN 4 ) (I) R 5 R 6 C=C(R 7 )(OC(O)R 8 ) (II)

[0114] R 9 R 10 C=CR 11 C(O)OC(O)CR 12 =CR 13 R 14 (lll)

[0115] R 30 R 31 C=CR32 (CN) (VI)

[0116] R 33 R 34 C=CR 35 (C(O)NR 36 R 37 ) (VII) in which

[0117] R 1 , R 2 and R 3 are independently of each other selected from the group consisting of H, CO2H and C1-C5 alkyl;

[0118] R 4 is selected from the group consisting of -NHC(CH3)2CH2C(O)CH3 and -OR 25 with R 25 selected from the group consisting of H and Ci-Cis alkyl optionally substituted with one or more group(s) selected from the group consisting of -OH, -CO2H, -SO3H, - OPO3 2 -C(O)OR 25 , -OC(O)R 25 , and a five- or six-membered heterocycle comprising at least one nitrogen atom in its ring chain;

[0119] R 25 is selected from the group consisting of C1-C5 alkyl and Cg-Ci2 aryl substituted with one or more CO2H functional groups; X2 is selected from the group consisting of -[-C(O)OC(R 26 )(R 27 )C(R 28 )(R 29 )-] W I- and a Ci-Cio alkyl hydrocarbon group optionally carrying one or more -OH, -CO2H or ester group(s); with wl being an integer from 1 to 50, advantageously from 1 to 25, preferably from 1 to 10, in particular from 1 to 5; R 26 , R 27 , R 28 , R 29 are independently of each other, independently for each wl unit, selected from the group consisting of H and C1-C5 alkyl; p' is 0 or 1;

[0120] R 5 , R 6 and R 7 are independently of each other selected from the group consisting of H and C1-C5 alkyl;

[0121] R 8 is C1-C5 alkyl;

[0122] R 9 , R 10 , R 11 , R 12 , R 13 , R 14 , R 15 , R 16 , R17 , R 18 , R 19 , R 20 , R 21 , R 22 , R 23 , R 24 , R 30 , R 31 , R 32 , R 33 , R 34 , R 35 are independently of each other selected from the group consisting of H and C1-C5 alkyl, preferably selected from the group consisting of H and CH3;

[0123] R 36 and R 37 are, independently of each other, selected from the group consisting of H and C1-C10 alkyl optionally substituted by one or more group(s) -OH, -CO2H, SO3H, -OPO3 2 -C(O)OR 38 , -OC(O)R 38 ; R 38 is selected from the group consisting of C1-C5 alkyl and C6-C12 aryl substituted with one or more CO2H functional groups.

[0124] More preferably, said polymer additive P2 is of formula (I), (III), or (IV) in which R 1 , R 2 and R3 are independently of each other selected from the group consisting of H, CO2H and C1-C3 alkyl;

[0125] R 4 is -OR 25 with R 25 selected from the group consisting of H and C1-C15 alkyl optionally substituted with one or more group(s) selected from the group consisting of -OH, -CO2H, SO3H, -OPO3 2 -C(O)OR 25 , -OC(O)R 25 , and a five- or six-membered heterocycle comprising at least one nitrogen atom in its ring chain;

[0126] R 25 is selected from the group consisting of C1-C5 alkyl and Cg-Cu aryl substituted with one or more CO2H functional groups;

[0127] X 2 is selected from the group consisting of -[-C(O)OC(R 26 )(R 27 )C(R 28 )(R 29 )-] WI- and a C1-C10 alkyl hydrocarbon group optionally carrying one or more -OH, -CO2H or ester group(s); with wl being an integer from 1 to 50, advantageously from 1 to 25, preferably from 1 to 10, in particular from 1 to 5; R 26 , R 27 , R 28 , R 29 are independently of each other, independently for each wl unit, selected from the group consisting of H and C1-C5 alkyl; p' is 0 or 1; R 9 , R 10 , R 11 , R 12 , R 13 , R 14 , R 15 , R 16 are independently of each other selected from the group consisting of H and C1-C5 alkyl, preferably selected from the group consisting of H and CH3.

[0128] In particular, said polymer additive P2 is of formula (I), (III) or (IV) in which R 1 , R 2 and R 3are independently of each other selected from the group consisting of H, CO2H and C1-C3 alkyl;

[0129] R 4 is -OR 25 with R 25 selected from the group consisting of H and C1-C10 alkyl optionally substituted with one or more group(s) selected from the group consisting of -OH, -CO2H, SO3H, -OPO3 2 -C(O)OR 25 , -OC(O)R 25 , and a five- or six-membered heterocycle comprising at least one nitrogen atom in its ring chain;

[0130] R 25 is selected from the group consisting of C1-C5 alkyl and Cg aryl substituted with one or more CO2H functional groups;

[0131] X 2 is selected from the group consisting of -[-C(O)OC(R 26 )(R 27 )C(R 28 )(R 29 )-] WI- and a C1-C5 alkyl hydrocarbon group optionally carrying one or more -OH, -CO2H or ester group(s); with wl being an integer from 1 to 5; R 26 , R 27 , R 28 , R 29 are independently of each other, independently for each wl unit, selected from the group consisting of H and C1-C5 alkyl; p' is 0 or 1;

[0132] R 9 , R 10 , R 11 , R 12 , R 13 , R 14 , R 15 , R 16 are independently of each other selected from the group consisting of H and C1-C5 alkyl, preferably selected from the group consisting of H and CH3.

[0133] More particularly, the polymer additive P2 comprises repeating units derived from a monomer M2 of formula (I), (III) or (IV) in which

[0134] R 1 , R 2 and R 3are independently of each other selected from the group consisting of H, CO2H and C1-C3 alkyl;

[0135] R 4 is -OR 25 with R 25 selected from the group consisting of H and C1-C10 alkyl optionally substituted with one or more group(s) selected from the group consisting of -OH, -CO2H, SO3H, -OPO3 2 -C(O)OR 25 , -OC(O)R 25 ;

[0136] R 25 is selected from the group consisting of C1-C5 alkyl and Cg aryl substituted with one or more CO2H functional groups;

[0137] X 2 is selected from the group consisting of -[-C(O)OC(R 26 )(R 27 )C(R 28 )(R 29 )-] W I- and a C1-C5 alkyl hydrocarbon group optionally carrying one or more -OH, -CO2H or ester group(s); with wl being an integer from 1 to 5; R 26 , R 27 , R 28 , R 29are independently of each other, independently for each wl unit, selected from the group consisting of H and C1-C5 alkyl; p' is 0 or 1;

[0138] R 9 , R 10 , R 13 , R 14 , R 15 , R 16 are H; R 11 and R 12 are CH3.

[0139] Preferably, the polymer additive P2 comprises repeating units derived from a monomer M2 of formula (I) R 1 R 2 C=C(R 3 )(HORN 4 ) (I), (III) as defined above or (IV) as defined above in which

[0140] R 1 , R 2 and R 3 are independently of each other selected from the group consisting of H, CO2H and C1-C3 alkyl;

[0141] R 4 is -OR 25 with R 25selected from the group consisting of H and C1-C5 alkyl optionally substituted with one or more group(s) selected from the group consisting of -OH, -CO2H, SO3H, -OPO3 2 -C(O)OR 25 , -OC(O)R 25 ;

[0142] R 25 is selected from the group consisting of C1-C alkyl and Cg aryl substituted with one or more CO2H functional groups;

[0143] R 9 , R 10 , R 13 , R 14 , R 15 , R 16 are H; R 11 and R 12 are CH3.

[0144] According to one embodiment, said polymer additive P2 is a homopolymer of said monomer M2 according to any one of formulas (I) to (VII) above. According to another embodiment, said polymer additive P2 is a copolymer of several monomers M2 according to any one of formulas (I) to (VII) above. By copolymer is meant repeating units derived from at least two monomers M2 according to any one of formulas (I) to (VII) above.

[0145] Thus, according to a particular embodiment, said polymer additive P2 may be a copolymer comprising: repeating units derived from a monomer M2a of formula (I), (III), (IV), (V), (VI) or (II)

[0146] R 1 R 2 C=C(R 3 )((X 2 )pC(O)R 4 ) (I)

[0147] R 9 R 10 C=CR 11 C(O)OC(O)CR 12 =CR 13 R 14 (lll)

[0148] R 30 R31 C=CR 32 (CN) (VI)

[0149] R 33 R 34 C=CR 35 (C(O)NR 36 R 37 ) (VII) in which

[0150] R 1 , R 2 and R 3 are independently of each other selected from the group consisting of H, CO2H and C1-C5alkyl;

[0151] R 4 is -OR 25 with R 25 selected from the group consisting of H and Ci-Cis alkyl substituted with one or more group(s) selected from the group consisting of -OH, -CO2H, SO3H, - OPO3 2- , -C(O)OR 25 , -OC(O)R 25 ;

[0152] R 25 is selected from the group consisting of C1-C5 alkyl and Cg-Ci2aryl substituted with one or more CO2H functional groups;

[0153] X 2 is selected from the group consisting of -[-C(O)OC(R 26 )(R 27 )C(R 28 )(R 29 )-] WI- and a C1-C10 alkyl hydrocarbon group optionally carrying one or more -OH, -CO2H or ester group(s); with wl being an integer from 1 to 50, advantageously from 1 to 25, preferably from 1 to 10, in particular from 1 to 5; R 26 , R 27 , R 28 , R 29 are independently of each other, independently for each wl unit, selected from the group consisting of H and C1-C5 alkyl; p' is 0 or 1;

[0154] R 9 , R 10 , R 11 , R 12 , R 13 and R 14 are independently of each other selected from the group consisting of H and C1-C5 alkyl, preferably selected from the group consisting of H and CH 3 ;

[0155] R 15 , R 16 , R 17 , R 18 , R 19 , R 20 , R 21 , R 22 , R 23 , R 24 , R 30 , R 31 , R 32 , R33 , R 34 and R 35 are independently of each other selected from the group consisting of H and C1-C5 alkyl, preferably selected from the group consisting of H and CH3; R 36 and R 37 are, independently of each other, selected from the group consisting of H and C1-C10 alkyl optionally substituted by one or more group(s) -OH, -CO2H, SO3H, -OPO3 2 -C(O)OR 38 , -OC(O)R 38 ; R 38 is selected from the group consisting of C1-C5 alkyl and Cg-Ci2aryl substituted with one or more CO2H functional groups; and repeating units derived from a monomer M2b of formula (I'), (II) or (III); or a mixture thereof

[0156] R 1 'R 2 'C=C(R 3 ')((X 2 ')p"-C(O)R 4 ') (I')

[0157] R 5 R 6 C=C(R 7 )(OC(O)R 8 ) (II) in which

[0158] R 1 ', R 2 and R 3 are independently of each other selected from the group consisting of H and C1-C5 alkyl; R 4 ' is selected from the group consisting of -NHCfCHshCFhCfOjCHs and -OR 25 ” with R 25 ” selected from the group consisting of Ci-Cis alkyl and a five- or six-membered heterocycle comprising at least one nitrogen atom in its ring chain;

[0159] X 2 ' is selected from the group consisting of -[-C(O)OC(R 26 ')(R 27 ')C(R 28 ')(R 29 ')-]wi - and a Ci-Cio alkyl hydrocarbon group optionally carrying one or more group(s) or ester(s); with wl' being an integer from 1 to 50, advantageously from 1 to 25, preferably from 1 to 10, in particular from 1 to 5; R 26 , R 27 , R 28 , R 29are independently of each other, independently for each wl' unit, selected from the group consisting of H and C1-C5 alkyl; p" is 0 or 1;

[0160] R 5 , R 6 and R 7 are independently of each other selected from the group consisting of H and C1-C5 alkyl;

[0161] R 8 is C1-C5 alkyl.

[0162] Preferably, said polymer additive P2 may be a copolymer comprising: repeating units derived from a monomer M2a of formula (I), (III), (IV), (V) R 1 R 2 C=C(R 3 )((X 2 ) P -HORN 4 ) (I)

[0163] R 9 R 10 C=CR 11 C(O)OC(O)CR 12 =CR 13 R 14 (lll) in which

[0164] R 1 , R 2 and R 3are independently of each other selected from the group consisting of H, CO2H and C1-C5 alkyl;

[0165] R 4 is -OR 25 with R 25 selected from the group consisting of H and C1-C10 alkyl substituted with one or more group(s) selected from the group consisting of -OH, -CO2H, SO3H, - OPO3 2- , -C(O)OR 25 , -OC(O)R 25 ;

[0166] R 25 is selected from the group consisting of C1-C3 alkyl and Cg-Cio aryl substituted with one or more CO2H functional groups;

[0167] X 2 is selected from the group consisting of -[-C(O)OC(R 26 )(R 27 )C(R 28 )(R 29 )-] WI- and a C1-C10 alkyl hydrocarbon group optionally carrying one or more -OH, -CO2H or ester group(s); with wl being an integer from 1 to 50, advantageously from 1 to 25, preferably from 1 to 10, in particular from 1 to 5; R 26 , R 27 , R 28 , R 29 are independently of each other, independently for each wl unit, selected from the group consisting of H and C1-C5 alkyl; p' is 0 or 1;

[0168] R 9 , R 10 , R 11 , R 12 , R 13 and R 14 are independently of each other selected from the group consisting of H and C1-C5 alkyl, preferably selected from the group consisting of H and CH 3 ;

[0169] R 15 , R 16 , R 17 , R 18 , R 19 , R 20 , R 21 , R 22 , R 23 , R 24are independently of each other selected from the group consisting of H and C1-C5alkyl, preferably selected from the group consisting of H and CH3; and repeating units derived from a monomer M2b of formula (I'), (II) or (III); or a mixture thereof

[0170] R 1 'R 2 'C=C(R 3 ')((X 2 ')p"-C(O)R 4 ') (I')

[0171] R 5 R 6 C=C(R 7 )(OC(O)R 8 ) (II) in which

[0172] R 1 ', R 2 and R 3 are independently of each other selected from the group consisting of H and C1-C3alkyl;

[0173] R 4 ' is -OR 25 ” with R 25 ” selected from the group consisting of Ci-Cio alkyl;

[0174] X 2 ' is selected from the group consisting of -[-C(O)OC(R 26 ')(R 27 ')C(R 28 ')(R 29')-]wi - and a Ci-Cio alkyl hydrocarbon group optionally carrying one or more group(s) or ester(s); with wl' being an integer from 1 to 50, advantageously from 1 to 25, preferably from 1 to 10, in particular from 1 to 5; R 26 , R 27 , R 28 , R 29 are independently of each other, independently for each wl' unit, selected from the group consisting of H and C1-C5alkyl; p" is 0 or 1;

[0175] R 5 , R 6 and R 7 are independently of each other selected from the group consisting of H and C1-C5 alkyl;

[0176] R 8 is C1-C5 alkyl.

[0177] In particular, said polymer additive P2 may be a copolymer comprising: repeating units derived from a monomer M2a of formula (I), (III), (IV), R 1 R 2 C=C(R 3 )(HORN 4 ) (I)

[0178] R 9 R 10 C=CR11 C(O)OC(O)CR 12 =CR 13 R 14 (lll) Tl in which

[0179] R 1 , R 2 and R 3 are independently of each other selected from the group consisting of H, CO2H and C1-C3alkyl;

[0180] R 4 is -OR 25 with R 25 selected from the group consisting of H and C1-C5alkyl substituted with one or more group(s) selected from the group consisting of -OH, -CO2H, SO3H, - OPO3 2 ', -C(O)OR 25 , -OC(O)R 25 ;

[0181] R 25 is selected from the group consisting of C1-C3alkyl and Cg aryl substituted with one or more CO2H functional groups;

[0182] R 9 , R 10 , R 11 , R 12 , R 13 and R 14are independently of each other selected from the group consisting of H and C1-C3alkyl, preferably selected from the group consisting of H and CH 3 ;

[0183] R 15 , R 16 are independently of each other selected from the group consisting of H and C1-C3alkyl, preferably selected from the group consisting of H and CH3; and repeating units derived from a monomer M2b of formula (I'), (II) or (III); or a mixture thereof

[0184] R 1 'R 2 'C=C(R 3 ')(HORN 4 ') (I') in which

[0185] R 1 ', R 2 and R 3 are independently of each other selected from the group consisting of H and C1-C3alkyl;

[0186] R 4 ' is -OR 25 ” with R 25 ” selected from the group consisting of C1-C5alkyl.

[0187] Certain copolymers are illustrated in the examples in a non-limiting manner.

[0188] According to a preferred embodiment, said polymer additive P2 has a molar mass by weight of between 500 g / mol and 50,000 g / mol, advantageously between 500 g / mol and 40,000 g / mol, preferably between 500 g / mol and 30,000 g / mol, more preferably between 500 g / mol and 25,000 g / mol, in particular between 500 g / mol and 20,000 g / mol, more particularly between 500 g / mol and 15,000 g / mol, preferably between 500 g / mol and 10,000 g / mol. The molecular or molar mass is determined by Size Exclusion Chromatography (CES). A test portion of the polymer solution corresponding to 90 mg of dry matter is introduced into a 10 mL bottle. Mobile phase, containing 0.04% dimethylformamide (DMF), is added to a total mass of 10 g. The composition of this mobile phase is as follows: NaHCOs: 0.05 mol / L, NaNOs: 0.1 mol / L, triethanolamine: 0.02 mol / L, NaNs 0.03% by mass.The CES system consists of a Waters 510 isocratic pump with a flow rate set at 0.8 mL / min, a Waters 717+ autosampler, an oven containing a 6 cm long, 40 mm inner diameter Waters Guard Column Ultrahydrogel precolumn, followed by a 30 cm long, 7.8 mm inner diameter Waters Ultrahydrogel linear column. Detection is performed using a Waters RI 410 differential refractometer. The oven is heated to 60°C and the refractometer is heated to 45°C. The CES system is calibrated with a series of sodium polyacrylate standards supplied by Polymer Standards Service with a peak molecular weight between 1000 g / mol and 1.10. 6 g / mol and a polydispersity index between 1.4 and 1.7. The calibration curve is linear and takes into account the correction obtained using the flow marker: dimethylformamide (DMF).

[0189] Said polymer P2 may comprise at least 50% by weight, advantageously at least 60%, preferably at least 70%, more preferably at least 80%, in particular at least 90% of repeating units derived from a monomer M2 of formula (I) or (II) or (III) or (IV) or (V) or (VI) or (VII) or a mixture thereof according to any one of the preferred embodiments described above. Preferably, said polymer P2 consists of repeating units derived from a monomer M2 of formula (I) or (II) or (III) or (IV) or (V) or (VI) or (VII) or a mixture thereof. The content in the different repeating units derived from the monomer M2 in the polymer P2 can be determined from the mass content of each of the monomers M2 used for the preparation thereof.

[0190] Use

[0191] Said composition according to the present invention can be prepared by mixing the different components thereof in the required proportions.

[0192] Said composition as described in the present application can be used in numerous applications. Thus, said composition can be used as a binder for an electrode (cathode or anode).

[0193] Said composition according to the present invention can be used as a binder for an electrode. Thus, the present invention provides an electrode composition comprising said composition according to the present invention, an active material and optionally a conductive agent. In a preferred embodiment, the electrode composition has the following mass composition: a. 50% to 99.95% of active material, preferably 50% to 99%, b. 0% to 25% of conductive agent, preferably 0.5% to 25%, c. 0.05% to 25% of said binder according to the invention, preferably 0.5% to 25%, d. 0% to 5% of at least one additive selected from the group consisting of a plasticizer, an ionic liquid, a dispersing agent for conductive additive, and a flow aid; the sum of all these percentages being 100%.

[0194] The conductive agents in the electrode are composed of one or more materials that can improve conductivity. Some examples include carbon blacks such as acetylene black, Ketjen black; carbon fibers, such as carbon nanotube, carbon nanofiber, vapor-grown carbon fiber; metal powders such as SUS powder, and aluminum powder.

[0195] Active materials in electrode compositions are materials that are capable of storing and releasing lithium ions.

[0196] In a preferred embodiment, said electrode is a negative electrode. In particular, for a negative electrode, said active material is selected from the group consisting of a lithium alloy, lithium metal, a metal oxide, a carbon material such as graphite or hard carbon, silicon, silicone, a silicon alloy and Li4Ti50i2. The shape of the negative electrode active material is not particularly limited but is preferably particulate.

[0197] In another preferred embodiment, said electrode is a positive electrode. Preferably, for a positive electrode, said active material is selected from the group consisting of LiCoCh, Li(Ni, Co, AI)C>2, Li(i + X )NiaMnbCo c(x represents a real number of 0 or more, a = 0.9, 0.8, 0.6, 0.5, or 1 / 3, b = 0.05, 0.1, 0.2, 0.3, or 1 / 3, c = 0.05, 0.1, 0.2, or 1 / 3), LiNiO2, LiMn2O4, LiCoMnO4, LisNiMnsOs, LÎ3Fe2(PO4)3, LÎ3V2(PO4)3, a spinel Li Mn substituted by a different element having a composition represented by Lil+xMn2-x-yMyO4, M represents at least one metal selected from Al, Mg, Co, Fe, Ni, and Zn, x and y independently represent a real number between 0 and 2, lithium titanate Li x TiO y- x and y independently representing a real number between 0 and 2, and a lithium metal phosphate having a composition represented by LiMPO4, M representing Fe, Mn, Co, or Ni. The shape of the positive electrode active material is not particularly limited but is preferably particulate. In addition, the surface of each of the materials described above can be coated. The coating material is not particularly limited as long as it has lithium ion conductivity and contains a material capable of being maintained as a coating layer on the surface of the active material. Examples of the coating material include LiNbOs, Li4Ti50i2, and LisPC.

[0198] Said electrode composition can be deposited on at least one face of a current collector to form said electrode. This deposition can be carried out in the presence of an organic solvent, water, a mixture of both or by a solvent-free process, i.e. by a dry coated electrode production process. Said organic solvent can be selected from the group consisting of n-methylpyrrolidone (NMP), dimethylsulfoxide (DMSO), N,N-dimethylformamide (DMF), triethylphosphite (TEP), acetone, cyclopentanone, tetrahydrofuran, methyl ethylketone (MEK), methyl isobutyl ketone (MiBK), ethyl acetate (EA), butyl acetate (BA), ethylene carbonate (EC), propylene carbonate (PC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), gamma-butyrolactone and N-butylpyrrolidone; and mixtures thereof.

[0199] Said method of preparing the dry coated electrode comprises the following steps:

[0200] - mixing the active material in powder form, said binder according to the present invention, and optionally the conductive agent in powder form, the additive in powder form or both to form said electrode composition according to the present invention;

[0201] - depositing said electrode composition on said current collector to manufacture an electrode, and

[0202] - optionally consolidation of said electrode by thermomechanical treatment.

[0203] Said dry coated electrode is thus prepared according to a “solvent-free” process, i.e. one which does not require a residual solvent evaporation step after the deposition step because all the constituents are mixed in the dry state, in powder form, and the deposition is also carried out without solvent. A thermomechanical treatment refers to the application of mechanical pressure to the electrode at a given temperature. Such a thermomechanical treatment can be carried out, for example, by a calendering machine comprising rollers which can be heated or a plate press which can also be heated.Solvent-free mixing processes for the various constituents of the electrode composition before the deposition phase on the collector include, but are not limited to: stirring mixing, air jet mixing, high shear mixing, V-mixer mixing, screw mass mixer mixing, double cone mixing, drum mixing, conical mixing, double Z-arm mixing, fluidized bed mixing, planetary mixer mixing, mechanical melting mixing, extrusion mixing, calendering mixing, grinding mixing.

[0204] According to one embodiment, after the powder mixing step, the electrode is manufactured by a solvent-free spraying process, by depositing the electrode composition on the metal substrate, by a pneumatic spraying process, by electrostatic spraying, by dipping in a fluidized powder bed, by sprinkling, by electrostatic screen printing, by deposition with rotating brushes, by deposition with rotating addition rollers, by calendering. According to one embodiment, the consolidation of the electrode after a deposition process on the metal substrate by solvent-free spraying (pneumatic spraying process, by electrostatic spraying, by dipping in a fluidized powder bed, by sprinkling, by electrostatic screen printing, by deposition with rotating brushes, by deposition with rotating addition rollers) is carried out by a calendering process.This process involves applying pressure to the electrode using two rollers, possibly heated. The consolidation step is optional. Its implementation depends on the technique used to deposit the constituents on the electrode. Thus, when the deposition step has been implemented by calendering, this consolidation step is optional because calendering allows the electrode to be deposited and consolidated simultaneously.

[0205] According to one embodiment, after the powder mixing step, the electrode is manufactured by a two-step solvent-free process. A first step consists of manufacturing a self-supporting film from the premixed formulation with a thermomechanical process such as extrusion, calendering or thermocompression. In a second step, the self-supporting film is laminated onto the metal substrate by a process combining temperature and pressure such as calendering or thermocompression.

[0206] According to one embodiment, after the powder mixing step, the electrode is manufactured by a solvent-free process using a calendering process which makes it possible to carry out the film-forming step and transfer of the coating onto the current collector in a single step, i.e. without going through a step of manufacturing a self-supporting film. To do this, the calender used has several rollers (at least three). The powder obtained after the mixing step is introduced between the first two rollers, most often heated and having differential rotation speeds to shear the powder. The coating formed and remaining stuck on the fastest roller is then directly laminated onto the current collector with a third roller. The electrode thus obtained can be subsequently passed through a calender to adjust its porosity or thickness if necessary.

[0207] According to another aspect of the present invention, a Li-ion battery is provided. Preferably, the Li-ion battery comprises a positive electrode, a negative electrode and a separator. At least one of the electrodes is an electrode according to the present invention. Preferably, said Li-ion battery also comprises a lithium salt selected from the group consisting of LiCF3SO3, LiPFg, LiCIO4, LiBF4, LiB(C2O4)2, LiN(SO2F)2, LiN(SO2CF3)2, LiN(SO2C2F3)2, LiN(SO2C2F5)2, LiN(SO2F)(SO2CF3), LiN(SO2F)(SO2C2F5), LiN(SO2CF3)(SO2C2F5), LiAsFg, LiBF2C2O4, LiNO3, LiPF3(CF2CF3)3, LiBETI, LiTDI, or a mixture thereof.

[0208] According to another aspect of the present invention, said composition can be used in the preparation of a conductive polymer, a solid electrolyte for fuel cells, a hydrophilic coating, a hydrophobic coating or a UV absorbing coating. Said composition can be used as an adhesive for a multilayer structure extruded in the form of a film, a sheet or a tube. Said composition can also be used as a coating on a metal.

[0209] Examples

[0210] For the examples below we use the following materials:

[0211] Solvent: NMP Sigma Aldrich anhydrous 99.5% (<50ppm H2O); Conducting agent: Carbon black Imerys C65; Active material: NMC 811; Fluoropolymer Pl: PVDF-AA comprising 1.1% by weight of acrylic acid in the PVDF chain; Polymer additive P2a: Poly(acrylic) acid with a molar mass by weight (Mw) of the order of 3000 to 4000 g / mol not containing functional groups containing a phosphorus atom; Polymer additive P2b: Poly(acrylic) acid with a molar mass by weight (Mw) of the order of 3000 to 4000 g / mol containing 1.8 mol% of functional groups containing a phosphorus atom per mol of polymer additive P2b.

[0212] Determination of the amount of functional groups containing a phosphorus atom The molar content of functional groups containing a phosphorus atom is determined by NMR 31 P and NMR 1H at hot (320°K). NMR spectra were performed on a Bruker AV III HD 500 spectrometer equipped with a 5mm BBI probe. The polymer additive P2 was dissolved in DMSO-d6. The signals located between 20 and 22 ppm in NMR 31 P, between 24 ppm and 31 ppm in NMR 31 P and between 28 ppm and 48 ppm in NMR 31 P and the signal at 6.9 ppm in NMR 1 H are characteristic of the functional groups containing a phosphorus atom present in said polymer additive P2. NMR analysis 1 H allows to determine the quantity of monomer M2 in said polymer additive P2. The signals to be integrated in NMR 1 H depend on the monomer M2 used. For example, for example B3 below, the characteristic signals of acrylic acid are located at 1 ppm and 2.7 ppm.

[0213] Preparation of the compositions

[0214] The fluoropolymer PI was mixed with said polymer additive P2 in a dry state (i.e. the two components are mixed in powder form) in the proportions detailed below in Table 1.

[0215] [Table 1]

[0216] * Ratio between the mass content of PI and the mass content of P2 in said composition

[0217] To the compositions prepared above, N-methylpyrrolidone (NMP) was added to form a solution with a mass of 100 g.

[0218] Preparation of electrode compositions C

[0219] A quantity of the solutions prepared above was added to 1.5g of conductive agent. The quantity of the solution was chosen so as to take 1.5g of composition B (i.e., the quantity of solution taken allows to prepare a composition C comprising 1.5g of (PI and P2)). The mixture was stirred 4 times with a Thinky ARE-250 mixer at 2000 rpm. 97g of active material was added to this mixture and the resulting mixture was stirred 3 times at 2000 rpm for 1 minute. NMP was added in three times (7g, 7g then 6.5g) followed by mixing for 1 minute at 2000 rpm after each addition. The solid content of the electrode compositions was 73%.

[0220] Rheological Analysis of Electrode Compositions After preparation, the electrode compositions are analyzed at 25°C using a TA HR10 rheometer. The geometry used is a 40mm parallel plate with a gap of 500pm. The flow curves are generated by performing a shear rate sweep from 0.1 s-1 to 100 s-1. The shear rate 10s-1 is used to compare all compositions.

[0221] Table 2 below details the viscosities at 25°C and 10s-l shear for the various prepared electrode compositions. Viscosity is expressed in centipoise (cP).

[0222] [Table 2] viscosity of composition Cl.

[0223] Evaluation of the sedimentation factor S

[0224] The solids content of the electrode compositions was measured using a PCE-MA-100 thermobalance from PCE Instruments. The analysis was carried out at 140°C. Two samples of electrode compositions were each introduced into a tubular HDPE pot with an inner diameter of 1 cm and a height of 5 cm. A thermobalance was carried out at t = 0 for the first sample by taking 1 ml of electrode composition. The second sample was left to stand for 120 h. After this standing time, 1 ml of electrode composition taken near the surface was analyzed by thermobalance to determine the solids content. The sedimentation factor S is calculated by the ratio between the solids content measured at t = 120 h and the solids content measured at t = 0. For composition C2, the sample is previously adjusted to a viscosity of the electrode composition of the order of 5700 cP.For this purpose, an amount of NMP was added to reduce the viscosity to the aforementioned value while maintaining a solids content of around 72%. The results are shown in Table 2 above. As demonstrated by the results presented in Table 2 above, when the polymer additive contains at least one functional group containing a phosphorus atom, a reduction in the viscosity of the electrode composition is observed, without the need for dilution, while maintaining a very high sedimentation factor. No sedimentation was observed for composition C3 after 120 hours. The applicant has thus surprisingly found a composition making it possible to prepare electrode compositions that are stable over time and have a viscosity suitable for electrode manufacture.

Claims

Claims 1. Composition comprising a fluorinated polymer carrying polar groups PI and a polymer additive P2 comprising repeating units derived from a monomer M2 of formula (I), (II), (III), (IV), (V), (VI), (VII) or a mixture thereof R 1 R 2 C=C(R 3 )((X 2 )pC(O)R 4 ) (I) R 5 R 6 C=C(R 7 )(OC(O)R 8 ) (II) R 9 R 10 C=CR 11 C(O)OC(O)CR 12 =CR 13 R 14 (lll) R 30 R 31 C=CR 32 (CN) (VI) R 33 R 34 C=CR 35 (C(O)NR 36 R 37 ) (VII) in which R 1 , R 2 and R 3 are independently of each other selected from the group consisting of H, CO2H and C1-C5 alkyl; R 4 is selected from the group consisting of -NHC(CH3hCH2C(O)CH3 and -OR25 with R 25 selected from the group consisting of H and Ci-Cis alkyl optionally substituted with one or more group(s) selected from the group consisting of -OH, -CO2H, SO3H, -OPO3 2 -C(O)OR 25 , -OC(O)R 25 , and a five- or six-membered heterocycle comprising at least one nitrogen atom in its ring chain; R 25 is selected from the group consisting of C1-C5 alkyl and Cg-Ci2 aryl substituted with one or more CO2H functional groups; X 2 is selected from the group consisting of -[-C(O)OC(R 26 )(R 27 )C(R 28 )(R 29 )-] W I- and a C1-C10 alkyl hydrocarbon group optionally carrying one or more -OH, -CO2H or ester group(s); with wl being an integer from 1 to 50, advantageously from 1 to 25, preferably from 1 to 10, in particular from 1 to 5; R 26 , R 27 , R 28 , R29 are independently of each other, independently for each wl unit, selected from the group consisting of H and C1-C5 alkyl; p' is 0 or 1; R 5 , R 6 and R 7 are independently of each other selected from the group consisting of H and C1-C5 alkyl; R 8 is C1-C5 alkyl; R 35 are independently of each other selected from the group consisting of H and C1-C5 alkyl, preferably selected from the group consisting of H and CH3; R 36 and R 37 are, independently of each other, selected from the group consisting of H and C1-C10 alkyl optionally substituted by one or more group(s) -OH, -CO2H, SO3H, -OPO3 2 -C(O)OR 38 , -OC(O)R 38 ; R 38is selected from the group consisting of C1-C5 alkyl and Cg-Ci2 aryl substituted by one or more CO2H functional groups; characterized in that said polymer additive P2 also comprises at least one functional group containing a phosphorus atom.

2. Composition according to the preceding claim, characterized in that the phosphorus content in said polymer additive P2 is between 0.01 and 15 mol% per mol of polymer additive P2.

3. Composition according to any one of the preceding claims, characterized in that the functional group containing a phosphorus atom is selected from the group consisting of -P(O)(OX + )-, -P(O)(OX + )2 and -P(O)(OX + )H with X selected from the group consisting of H, Na, Li and K.

4. Composition according to any one of the preceding claims, characterized in that the mass ratio between said fluorinated polymer PI and said polymer additive P2 is greater than or equal to 1, advantageously greater than or equal to 5, preferably greater than or equal to 10, more preferably greater than or equal to 15, in particular greater than or equal to 20.

5. Composition according to any one of the preceding claims, characterized in that the mass ratio between said fluorinated polymer PI and said polymer additive P2 is less than or equal to 1000, preferably less than or equal to 400.

6. Composition according to any one of the preceding claims, characterized in that said polymer PI comprises repeating units derived from a monomer Mla selected from the group consisting of vinyl fluoride; vinylidene fluoride (VDF); trifluoroethylene (TrFE); chlorotrifluoroethylene (CTFE); 1,2-difluoroethylene; tetrafluoroethylene (TFE); hexafluoropropylene (HFP); perfluoro(alkyl vinyl) ethers such as perfluoro(methyl vinyl) ether (PMVE), perfluoro(ethyl vinyl) ether (PEVE) and perfluoro(propyl vinyl) ether (PPVE); perfluoro(1,3-dioxole); perfluoro(2,2-dimethyl-1,3-dioxole) (PDD); the product of formula CF2=CFOCF2CF(CF3)OCF2CF2X in which X is SO2F, CO2H, CH2OH, CH2OCN or CH2OPO3H; the product of formula CF2=CFOCF2CF2SC>2F; the product of formula F(CF2)nCH2OCF=CF2 in which n is 1, 2, 3, 4 or 5; the product of formula R 1 CH2OCF=CF2 in which R 1 is hydrogen or F(CF2)m and m is 1, 2, 3 or 4; the product of formula R 2OCF=CH2 in which R 2 is F(CF2)p and p is 1, 2, 3 or 4; perfluorobutylethylene (PFBE); trifluoropropene, tetrafluoropropene, hexafluoroisobutylene, perfluorobutylethylene, pentafluoropropene, bromotrifluoroethylene, chlorofluoroethylene, chlorotrifluoropropene and 2-trifluoromethyl-3,3,3-trifluoro-l-propene or a mixture thereof.

7. Composition according to any one of the preceding claims, characterized in that said fluoropolymer PI comprises repeating units derived from the monomer Mla and repeating units derived from a monomer Mlc and optionally repeating units derived from a monomer Mlb; said monomer Mla being vinylidene fluoride; said monomer Mlb selected from the group consisting of vinyl fluoride; trifluoroethylene (TrFE); chlorotrifluoroethylene (CTFE); 1,2-difluoroethylene; tetrafluoroethylene (TFE); hexafluoropropylene (HFP); perfluoro(alkyl vinyl) ethers such as perfluoro(methyl vinyl) ether (PMVE), perfluoro(ethyl vinyl) ether (PEVE) and perfluoro(propyl vinyl) ether (PPVE); perfluoro(1,3-dioxole); perfluoro(2,2-dimethyl-1,3-dioxole) (PDD); the product of formula CF2=CFOCF2CF(CF3)OCF2CF2X in which X is SO2F, CO2H, CH2OH, CH2OCN or CH2OPO3H; the product of formula CF2=CFOCF2CF2SC>2F;the product of formula F(CF2)nCH2ÛCF=CF2 in which n is 1, 2, 3, 4 or 5; the product of formula R; 1 CH2ÛCF=CF2 in which R 1 is hydrogen or F(CF2)m and m is 1, 2, 3 or 4; the product of formula R 2 OCF=CH2 in which R 2 is F(CF2)p and p is 1, 2, 3 or 4; perfluorobutyl ethylene (PFBE); trifluoropropene, tetrafluoropropene, hexafluoroisobutylene, perfluorobutylethylene, pentafluoropropene, bromotrifluoroethylene, chlorofluoroethylene, chlorotrifluoropropene and 2-trifluoromethyl-3,3,3-trifluoro-l-propene or a mixture thereof; said monomer Mlc being selected from the group consisting of formula R a R b C=C(R c )((X 3 ) P "HORN d ) in which the substituents R a , R b and R c are independently of each other selected from the group consisting of H, CO2H and C1-C5 alkyl; R dis selected from the group consisting of -NHCfCHshCI-hCfOjCHs or -OR d ' with R d ' selected from the group consisting of H and Ci-Cis alkyl optionally substituted by one or more group(s) -OH, -CO2H, -SO3H, - PO3H, -OC(O)R d ", -C(O)OR d " or a five- or ten-membered heterocycle comprising at least one nitrogen atom in its ring chain; R d " being selected from the group consisting of C1-C8 alkyl or C1-C8 aryl optionally substituted by one or more -OH, -CO2H, -SO3H, -PO3H group(s); p" is 0 or 1; X 3 is selected from the group consisting of -[-C(O)OC(R 26 ')(R 27 ')C(R 28 ')(R 29 ')-] W 2- and a C1-C10 alkyl hydrocarbon group optionally carrying one or more -OH, -CO2H or ester group(s); with w2 being an integer from 1 to 50, advantageously from 1 to 25, preferably from 1 to 10, in particular from 1 to 5; R26 ', R 27 ', R 28 ', R 29 ' are independently of each other, independently for each w2 unit, selected from the group consisting of H and C1-C5 alkyl.

8. Composition according to the preceding claim, characterized in that said monomer Mlc is present in said polymer PI in a molar content of 0.01% to 5%.

9. Composition according to any one of the preceding claims 6 or 7, characterized in that said monomer Mlb is present in said polymer PI in a molar content of 1% to 25%.

10. Composition according to any one of the preceding claims, characterized in that said polymer additive P2 has a molar mass by weight of between 500 g / mol and 50,000 g / mol, preferably between 500 g / mol and 25,000 g / mol.

11. Composition according to any one of the preceding claims, characterized in that said polymer additive P2 comprises repeating units derived from a monomer M2 of formula (I), (III) or (IV) in which R 1 , R 2 and R 3 are independently of each other selected from the group consisting of H, CO2H and C1-C3 alkyl; R 4 is -OR 25 with R 25 selected from the group consisting of H and C1-C15 alkyl optionally substituted with one or more group(s) selected from the group consisting of -OH, -CO2H, SO3H, -OPOs 2- , -C(O)OR 25 , -OC(O)R 25 , and a five- or six-membered heterocycle comprising at least one nitrogen atom in its ring chain; R 25 is selected from the group consisting of C1-C5 alkyl and Cg-Ci2 aryl substituted with one or more CO2H functional groups; X 2is selected from the group consisting of -[-C(O)OC(R 26 )(R 27 )C(R 28 )(R 29 )-] W I- and a C1-C10 alkyl hydrocarbon group optionally carrying one or more -OH, -CO2H or ester group(s); with wl being an integer from 1 to 50, advantageously from 1 to 25, preferably from 1 to 10, in particular from 1 to 5; R 26 , R 27 , R 28 , R 29 are independently of each other, independently for each wl unit, selected from the group consisting of H and C1-C5 alkyl; p' is 0 or 1; R 9 , R 10 , R 11 , R 12 , R 13 , R 14 , R 15 , R 16 are independently of each other selected from the group consisting of H and C1-C5 alkyl, preferably selected from the group consisting of H and CH3.

12. Composition according to any one of the preceding claims, characterized in that said polymer additive P2 comprises repeating units derived from a monomer M2 of formula (I), (III) or (IV) in which R 1 , R 2 and R 3 are independently of each other selected from the group consisting of H, CO2H and C1-C3 alkyl; R 4 is -OR 25 with R 25 selected from the group consisting of H and C1-C10 alkyl optionally substituted with one or more group(s) selected from the group consisting of -OH, -CO2H, SO3H, -OPOs 2- , -C(O)OR 25 , -OC(O)R 25 , and a five- or six-membered heterocycle comprising at least one nitrogen atom in its ring chain; R 25 is selected from the group consisting of C1-C5 alkyl and Cg aryl substituted with one or more CO2H functional groups; X 2is selected from the group consisting of -[-C(O)OC(R 26 )(R 27 )C(R 28 )(R 29 )-] W I- and a C1-C5 alkyl hydrocarbon group optionally carrying one or more -OH, -CO2H or ester group(s); with wl being an integer from 1 to 5; R 26 , R 27 , R 28 , R 29 are independently of each other, independently for each wl unit, selected from the group consisting of H and C1-C5 alkyl; p' is 0 or 1; R 9 , R 10 , R 11 , R 12 , R 13 , R 14 , R 15 , R 16 are independently of each other selected from the group consisting of H and C1-C5 alkyl, preferably selected from the group consisting of H and CH3.

13. Composition according to any one of the preceding claims, characterized in that it has a sedimentation factor S of between 0.8 and 1.1; calculated according to the protocol detailed in the present application.

14. A binder for a Li-ion battery comprising said composition according to any one of the preceding claims.

15. Electrode composition comprising an active material and said binder according to the preceding claim.

16. Electrode for a lithium-ion battery comprising a metal collector of which at least one face is covered with said electrode composition according to the preceding claim.

17. Li-ion secondary battery comprising an anode, a cathode and a separator, wherein the anode or the cathode is an electrode according to the preceding claim.

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