Battery electrode and method for manufacturing same

Abstract

The present invention relates to a powdered electrode composition, a method for its preparation, and its use for the manufacture of electrochemical cell components.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to European Patent Application No. 22306333.0, filed April 8, 2022, the entire contents of which are incorporated herein by reference for all purposes.

[0002] The present invention relates to a powdered electrode composition, a method for its preparation, and its use for the manufacture of electrochemical cell components. [Background technology]

[0003] To date, electrodes for lithium secondary batteries are primarily manufactured by a wet process that involves preparing a slurry in which electrode active materials, additives, and binders are dispersed in a solvent or aqueous medium, and processing the slurry to form an electrode film.

[0004] Dry electrode processes were developed to reduce the time-consuming and costly drying procedures required by the wet processes described above.

[0005] Typical dry processes utilize the fibrillating properties of certain polymers to provide a matrix for the embedded conductive material. Some polymers in the fluoropolymer family, such as polytetrafluoroethylene (PTFE), are particularly inert and stable in common electrode solvents used in secondary batteries, even those with organic solvents at high operating or storage temperatures. Therefore, the stability of electrodes made with PTFE can be higher than those made with other binders.

[0006] For example, a dry electrode fabrication process can involve combining a PTFE binder with the active electrode material in powder form and calendering to form an electrode film. However, while PTFE has good adhesion to the electrode active material, it has difficulty adhering to the current collector.

[0007] Another drawback of PTFE relates to its limited electrochemical stability on the anode side, which can lead to polymer degradation and lower coulombic efficiency when used as a binder for the anode.

[0008] Furthermore, when the anode is made from silicon, one of the key obstacles to overcome is the significant volume changes that occur in the silicon active material as it absorbs (expands) and desorbs (contracts) lithium during charge-discharge cycling. These substantial contraction-swelling cycles impose high mechanical stresses on the anode layer, causing circuit damage and poor contact, resulting in reduced capacity and eventual failure of the electrochemical cell.

[0009] One approach to overcoming the unique challenges associated with silicon is to create a self-healing mechanism within the binder matrix by incorporating weak bonding interactions that allow for some degree of reversibility. These unstable bonds can then be broken under stress but reform upon relaxation without irreparable damage to the active material particles. Unfortunately, PTFE cannot interact closely with the active material through such bonding interactions, making it a poor binder candidate for silicon-rich anodes.

[0010] Many approaches are being pursued to develop next generation binders compatible with silicon anodes.

[0011] There are several polycarboxylate binders and derivatives being pursued, including polyacrylic acid, polyamic acid, polyacrylamide, and other hydrogen-bonding structures.

[0012] The applicant has unexpectedly found that certain polymers obtained by copolymerization of at least one monomer having a carboxyl group with at least one monomer having an acrylamide can be used in dry electrode fabrication processes, particularly in processes for manufacturing silicon-rich anodes, so that electrodes can be provided by a highly efficient process. Summary of the Invention

[0013] Thus, in one aspect, the present invention provides a method for producing a medicament for the treatment of a pulmonary arthritis, comprising: i) providing a polymer (P), the polymer (P) comprising: (A) a repeating unit derived from at least one α,β-ethylenically unsaturated carboxylic acid monomer [monomer (AA)]; (B) Formula (I): [ka] (In the formula, R 5 represents a hydrogen atom or a methyl group, and R 6 and R 7 are the same or different and may be selected from a hydrogen atom or a linear or branched alkyl group having 1 to 6 carbon atoms; R 8 and R 9 may be the same or different and may be selected from the group consisting of a hydrogen atom, a linear or branched alkyl group having 1 to 6 carbon atoms, a carboxyl group, and an amide group. and a repeating unit derived from at least one (meth)acrylamide monomer [monomer (AM)] of the formula: (C) Optional repeating units derived from at least one monomer (M) selected from the group consisting of monomers (M1) and (M2). And, the monomer (M1) has the following formula (II): [ka] (In the formula, R 1is H or an alkyl group, the alkyl group being preferably a methyl group; R 2 is H or an alkyl group, R 3 and R 4 are the same or different and may be selected from a hydrogen atom or a linear or branched alkyl group having 1 to 6 carbon atoms, A is, - a single covalent bond, and - Spacer is a bond selected from the group consisting of X, Y and Z are independently selected from carbon atoms or nitrogen atoms; a, b, and c are each independently selected from the integers 1 to 2; Each dashed dotted line represents an optional double bond. an ethylenically unsaturated monomer having an unsaturated heterocyclic group having at least one nitrogen atom, the monomer (M2) is different from the monomers (AA) and (AM) and has the following formula (III): [ka] (In the formula, R i is selected from the group consisting of H, —COOH, —CHCOOH or an alkyl group, the alkyl group being preferably a methyl group; R ii and R iii are the same or different and may be selected from a hydrogen atom or a linear or branched alkyl group having 1 to 6 carbon atoms, or may be a -COOH group; B is a bond selected from the group consisting of a —C(O)—O— group and a —C(O)—NH— group; R xis a straight-chain or branched C3-C alkyl group containing at least one functional group selected from the group consisting of a hydrogen atom, an ether (-O-), a heterocyclic group, a sulfonic acid group (-SO3H), a salt of a sulfonic acid group (-SO3Cat), a phosphonic acid group (-PO3H2), a salt of a phosphonic acid group (-PO3Cat2), a phosphoric acid group (-OPO3H2), and a salt of a phosphoric acid group (-OPO3Cat2). 20 Cat is preferably a monovalent cation selected from alkali metal cations, more preferably Na + , K. + and Li + (selected from and a repeat unit having the formula: a process comprising: -ii) dry-mixing, in the absence of a solvent, at least one electrode active material (AM), the polymer (P) provided in step i) as defined above, and optionally at least one conductive agent to obtain a dry electrode-forming composition [composition (C)]; -iii) feeding the composition (C) obtained in step ii) into a press to form a self-supporting dry film; and -iv) applying the dry film to a conductive substrate to form an electrode; The present invention provides a method for producing an electrode for an electrochemical cell [electrode (E)] comprising, or preferably consisting of, the following:

[0014] In another aspect, the present invention provides an electrode (E) for a secondary battery, obtainable by the method defined above.

[0015] The polymer (P) can be advantageously used as the sole binder or in a blend with PTFE, which gives high adhesion even at processing temperatures that are not too high (around 100° C.).

[0016] Therefore, in another aspect, the present invention provides a method for producing an electrode for an electrochemical cell [electrode (E1)], comprising the steps of: step I) combining polytetrafluoroethylene (PTFE) with the polymer (P) defined above to provide a binder (B); - step II) dry-mixing, in the absence of a solvent, at least one electrode active material (AM), a binder (B) as defined above, and optionally at least one conductive agent to provide a dry electrode-forming composition [composition (C)]; - step III) feeding the composition (C1) obtained in step II) into a press to form a self-supporting dry film; and Step IV) applying the dry film to a conductive substrate to form an electrode. The present invention provides a method comprising:

[0017] In another aspect, the present invention provides an electrode (E1) for a secondary battery, obtainable by a method as defined above.

[0018] In a further aspect, the present invention relates to an electrochemical device, such as a secondary battery or a capacitor, comprising at least one electrode (E) or electrode (E1) as defined above. DETAILED DESCRIPTION OF THE INVENTION

[0019] In the context of the present invention, the term "weight percent" (wt%) refers to the content of a particular component in a mixture, calculated as the ratio between the weight of the particular component and the total weight of the mixture. When referring to repeating units derived from a certain monomer in a polymer / copolymer, weight percent (wt%) refers to the ratio between the weight of the repeating units of that monomer to the total weight of the polymer / copolymer. When referring to the total solids content of a liquid composition, weight percent (wt%) refers to the ratio between the weights of all non-volatile components in the liquid.

[0020] As used herein, the terms "adhere" and "adhesion" refer to two layers being permanently joined to one another via their contact surfaces.

[0021] The term "electrochemical device" is intended herein to mean an electrochemical cell / assembly comprising a positive electrode, a negative electrode, and a liquid electrolyte, wherein a single-layer or multi-layer separator is in contact with at least one surface of one of the electrodes. Non-limiting examples of suitable electrochemical devices include, inter alia, secondary batteries, particularly alkaline or alkaline-earth secondary batteries such as lithium-ion batteries, lead-acid batteries, and capacitors, particularly lithium-ion-based capacitors and electric double-layer capacitors (supercapacitors). Non-limiting examples of electrochemical cells include, inter alia, batteries, preferably secondary batteries, electric double-layer capacitors.

[0022] For the purposes of the present invention, "secondary battery" is intended to denote a rechargeable battery. Non-limiting examples of secondary batteries include alkaline or alkaline earth secondary batteries, among others.

[0023] Polymer (P) In step i) of the process of the present invention, a polymer (P) is provided, which polymer (P) is obtainable by radical copolymerization of a mixture of at least one α,β-ethylenically unsaturated carboxylic acid monomer (AA) and at least one (meth)acrylamide monomer [monomer (AM)] as defined above.

[0024] The at least one α,β-ethylenically unsaturated carboxylic acid monomer (AA) preferably has the formula (IV): [ka] (In the formula, R a , R b and R c are the same or different and are independently selected from a hydrogen atom and a C1-C3 hydrocarbon group. is a compound of

[0025] More preferably, monomer (AA) is a compound of formula (IV) as defined above selected from the group consisting of acrylic acid, methacrylic acid, Sipomer BETA CEA (sold by Solvay), ethacrylic acid, croton, methyl(meth)acrylic acid, ethyl(meth)acrylic acid, propyl(meth)acrylic acid, isopropyl(meth)acrylic acid, n-butyl(meth)acrylic acid, 2-ethylhexyl(meth)acrylic acid, n-hexyl(meth)acrylic acid and n-octyl(meth)acrylic acid.

[0026] The metha(cryl)amide monomer of formula (II) [monomer (AM)] is preferably selected from the group consisting of metha(cryl)amide or N-substituted metha(cryl)amides, such as N-alkylacrylamides, N,N-dialkylacrylamides.

[0027] According to one embodiment of the present invention, the polymer (P) comprises at least one monomer (M1), which is an ethylenically unsaturated monomer having an unsaturated heterocyclic group having at least one nitrogen atom as defined above.

[0028] The "unsaturated heterocyclic group having at least one nitrogen atom" in the monomer (M1) of formula (II) is preferably a 5- to 6-membered aromatic cyclic group having at least one N in the ring, for example, [ka] (wherein * represents the attachment point of bond A) Includes:

[0029] Bond A and Residue R 2 may be attached to the heterocyclic group at any position on either a carbon atom or a nitrogen atom.

[0030] Monomer (M1) may be, for example: - Formula (IIa): [ka] Vinylimidazole (VIm) Formula (IIb) [ka] 2-methyl-1-vinylimidazole - Formula (IIc) [ka] 1-vinyl-1,2,4-triazole Formula (IId) [ka] 2-vinylpyrazine Formula (IIe) [ka] of 4-vinylpyridine - Expression (IIf) [ka] of 2-vinylpyridine Formula (IIg) [ka] Hydroxyl-(meth)acrylate imidazole derivatives of.

[0031] The divalent spacer group A in formula (II) is typically a group -CO-NH-(CH) n -, -CO-O-(CH2) n or -CO-O-(CH2) n -O-CO-, for example, formula (II-X): [ka] (In the formula, R 6 , R 8 and R 9 is as defined above) and a compound of Formula (II-Y): [ka] (In the formula, R 2 is as defined above, and A 1 and A 2 are two groups that react together to form a covalent bond) Any other covalent linking group may also be envisaged, such as that obtained by reaction with a compound of the formula:

[0032] For example, A 2 is -(CH2) m -NH2 group, where m is 1 to 4, preferably 2 or 3. In that case, A 1 may be, for example, a carboxylic acid, an acid chloride, an acid anhydride, or an epoxy.

[0033] According to another variant, A 2 is -(CH2) m In the formula, m is 1 to 4, preferably 2 or 3. In that case, A 1 may be, for example, a carboxylic acid, an acid chloride, anhydride or an ester.

[0034] According to this embodiment, the polymer (P) is a polymer obtained by copolymerizing the monomers (AA), (AM) and at least one monomer (M1), i.e. a polymer having a structure obtained by such polymerization, although the polymer (P) does not necessarily have to be obtained by this process. Alternatively, the polymer (P) can be obtained, for example, by a first step of copolymerizing the monomers (AA), (AM) and the compound of formula (II-X), resulting in the polymer (P0), and then a second step of post-grafting the polymer (P0) by reaction with the compound (II-Y).

[0035] A in compound (II-Y) 2 Ga-(CH2) mWhen it is an —NH group, compound (II-X) may advantageously be chosen from additional acrylic or methacrylic acid or their esters, maleic anhydride, vinylbenzyl chloride, glycidyl methacrylate and (blocked) isocyanatoethyl methacrylate.

[0036] A in compound (II-Y) 2 Ga-(CH2) m When it is an —OH group, compound (II-X) may advantageously be chosen from additional acrylic acid, methacrylic acid, maleic anhydride or esters thereof.

[0037] In addition, quaternization of all or part of the imidazole functional groups of the polymer (P) may occur and may result from quaternization of all or part of the monomers and / or subsequent quaternization of all or part of the imidazole functional groups of the polymer.

[0038] According to another embodiment of the invention, the polymer (P) comprises at least one monomer (M2) of formula (III) as defined above.

[0039] Residue R of monomer (M2) x The "heterocyclic group" in the above formula (I) includes saturated heterocyclic groups having at least one nitrogen atom compound such as imidazolidinone.

[0040] According to a first variant in which B in formula (III) is a —C(O)—O— group, the monomer (M2) is for example a compound of formula (IIIa) [ka] The compound - Formula (IIIb) [ka] The compound or - Formula (IIIc) [ka] Compounds of In formulas (IIIa) to (IIc), R i , R ii and R iii is as defined above, and n is an integer from 1 to 40.

[0041] According to a second variant in which B in formula (III) is a —C(O)—NH— group, the monomer (M2) is, for example, a compound of formula (IIId) [ka] or a compound of formula (IIIe) [ka] In formula (IIId) and (IIIe), R i , R ii and R iii is as defined above.

[0042] According to this embodiment, the polymer (P) is a polymer obtained by copolymerizing the monomers (AA), (AM) and at least one monomer (M2), i.e. a polymer having a structure obtained by such a polymerization, although the polymer (P) does not necessarily have to be obtained by this process.

[0043] The at least one polymer (P) may further comprise less than 10 mol % of one or more further monomers (M') selected from the group consisting of hydrophobic and amphiphilic monomers, provided that the total amount of monomers (AA) and / or monomers (AM) is at least 60 mol % relative to the total number of moles of repeating units of the polymer (P).

[0044] In this embodiment, in which an additional monomer (M') is present in the polymer (P), said hydrophobic and / or amphiphilic monomer is a monoethylenically unsaturated monomer: alkyl esters of maleic anhydride and (meth)acrylic acid, such as monomethyl maleic anhydride, dimethyl maleic anhydride, monoethyl maleic anhydride, diethyl maleic anhydride, methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-hexyl (meth)acrylate, n-octyl (meth)acrylate, hydroxyalkyl esters of maleic anhydride and (meth)acrylic acid, such as monohydroxyethyl maleic anhydride, dihydroxyethyl maleic anhydride, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, Ethoxylates and propoxylates derived from maleic anhydride, such as poly(propylene oxide)-b-poly(ethylene oxide) maleic acid half-esters or diesters, alkyl-poly(ethylene oxide) maleic acid half-esters or diesters, ethoxylates and / or propoxylates derived from the ethoxylation and / or propoxylation of hydroxyalkyl(meth)acrylic acids, such as poly(propylene oxide)-b-poly(ethylene oxide)-ethyl(meth)acrylate, - ethoxylates and / or propoxylates resulting from the esterification (transesterification) of (meth)acrylic acid and esters, such as poly(propylene oxide)-b-poly(ethylene oxide)(meth)acrylates and alkyl-poly(ethylene oxide)(meth)acrylates, vinyl esters, such as methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether, 2-ethylhexyl vinyl ether, vinylcyclohexyl ether, dodecyl vinyl ether, 2-(diethylamino)ethyl vinyl ether, 2-(di-n-butylamino)ethyl vinyl ether, allyl ethers, such as methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether, 2-ethylhexyl vinyl ether, vinyl esters, such as vinyl acetate or vinyl propionate, alkyl-substituted acrylamides, such as N-tert-butylacrylamide or N-methyl(meth)acrylamide is selected from the group consisting of:

[0045] Preferably, the additional monomer (M') present in the polymer (P) is - Monoethyl maleic anhydride, diethyl maleic anhydride, methyl (meth)acrylate, ethyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate - Monohydroxyethyl maleic anhydride, dihydroxyethyl maleic anhydride, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate - Poly(propylene oxide)-b-poly(ethylene oxide) maleic acid half ester - Poly(propylene oxide)-b-poly(ethylene oxide)-ethyl(meth)acrylate - Poly(propylene oxide)-b-poly(ethylene oxide) (meth)acrylate, alkyl-poly(ethylene oxide) (meth)acrylate - Vinyl acetate, vinyl propionate is selected from the group consisting of:

[0046] The proportion in moles of monomer (M') cannot exceed 10% by mole of the total number of moles of monomers (AA+AM+M+M') present in polymer (P). Advantageously, the proportion in moles of monomer (M') is less than 5% by mole.

[0047] At least one polymer (P) may further comprise less than 1 mol % of one or more further crosslinking monomers (XL-M) containing at least two ethylenic unsaturations.

[0048] In this embodiment in which an additional monomer (XL-M) is present in the polymer (P), said crosslinking monomer is selected from the group consisting of N,N'-methylenebisacrylamide (MBA), N,N'-ethylenebisacrylamide, polyethylene glycol (PEG) diacrylates, triacrylates, divinyl ethers, typically trifunctional divinyl ethers such as tri(ethylene glycol) divinyl ether (TEGDE), N-diallylamine, N,N-diallyl-N-alkylamines, their acid addition salts and their quaternization products (where alkyl as used here is preferentially (C1-C3) alkyl), compounds of N,N-diallyl-N-methylamine and of N,N-diallyl-N,N-dimethylammonium, such as chlorine. or alternatively may be selected from ethoxylated trimethylolpropane triacrylate, ditrimethylolpropane tetraacrylate (DiTMPTTA), divinylbenzene (DVB), ethoxylated or propoxylated bisphenol A diacrylate, dipropylene glycol diacrylate (DPGDA), tripropylene glycol diacrylate (TPGDA), propoxylated di(meth)acrylates, butyloxylated di(meth)acrylates, dimethylacrylamide, 1,4-butanediol dimethacrylate (BDDMA), 1,6-hexanediol dimethacrylate (HDDMA), 1,3-butylene glycol dimethacrylate (BGDMA) and derivatives thereof.

[0049] The proportion in molar terms of the monomer (XL-M) cannot exceed 1 mol % of the total number of moles of monomers (AA+AM+M+M'+XL-M) present in the polymer (P), in order to avoid gel formation and viscosity increase. Advantageously, the proportion in molar terms of the monomer (M') is less than 0.5 mol %.

[0050] According to said embodiment, the polymer (P) obtained by polymerization further comprising monomers (XL-M) is at least partially crosslinked.

[0051] In one preferred embodiment of the invention, no further monomers (M') or (XL-M) are present in the polymer (P).

[0052] Typically, the polymer (P) is at least one monomer (AA), at least one monomer (AM), - optionally at least one monomer (M), - optionally at least one monomer (M'), and - optionally at least one monomer (XL-M), in the presence of a free radical source.

[0053] Any source of free radicals can be used. It is particularly possible to generate free radicals spontaneously using a suitable monomer such as styrene, for example by increasing the temperature. It is possible to generate free radicals by irradiation, particularly UV irradiation, preferably in the presence of a suitable UV-sensitive initiator. It is possible to use radical or redox-type initiators or initiator systems. The free radical source may or may not be water-soluble. It may be preferable to use a water-soluble initiator or an initiator that is at least partially water-soluble.

[0054] Generally, the higher the amount of free radicals, the easier it is to initiate (promote) the polymerization, but the lower the molar mass of the resulting copolymer. peroxides, such as hydrogen peroxide, tert-butyl hydroperoxide, cumene hydroperoxide, tert-butyl peroxyacetate, tert-butyl peroxybenzoate, tert-butyl peroxyoctoate, tert-butyl peroxyneodecanoate, tert-butyl peroxyisobutyrate, lauroyl peroxide, tert-amyl peroxypivalate, tert-butyl peroxypivalate, dicumyl peroxide, benzoyl peroxide, sodium persulfate, potassium persulfate or ammonium persulfate, azo compounds, such as 2,2'-azobisisobutyronitrile, 2,2'-azobis(2-butanenitrile), 4,4'-azobis(4-pentanoic acid), 1,1'-azobis(cyclohexanecarbonitrile), 2-(t-butylazo)-2-cyanopropane, 2,2'-azobis{2-methyl-N-[1,1-bis(hydroxymethyl)-2-hydroxyethyl]propionamide}, 2,2'-azobis[2-methyl-N-(hydroxyethyl)propionamide], 2,2'-azobis(N,N'-dimethyleneisobutyl amidine) dihydrochloride, 2,2'-azobis(2-amidinopropane) dihydrochloride, 2,2'-azobis(N,N'-dimethyleneisobutyramide), 2,2'-azobis{2-methyl-N-[1,1-bis(hydroxymethyl)-2-hydroxyethyl]propionamide}, 2,2'-azobis{2-methyl-N-[1,1-bis(hydroxymethyl)ethyl]propionamide}, 2,2'-azobis[2-methyl-N-(2-hydroxyethyl)propionamide] or 2,2'-azobis(isobutyramide) dihydrate, - redox systems, such as those containing a combination of hydrogen peroxide, alkyl peroxides, peresters, percarbonates, persulfates, etc., and optionally iron salts, titanium salts, zinc formaldehyde sulfoxylate or sodium formaldehyde sulfoxylate in admixture with reducing sugars; alkali metal or ammonium persulfates, perborates or perchlorates in combination with alkali metal bisulfites such as sodium metabisulfite and reducing sugars, and - Alkali metal persulfates in combination with aryl phosphinic acids such as benzenephosphonic acid and others of similar nature and reducing sugars may in particular be used.

[0055] The polymerization temperature may in particular be between 25°C and 95°C. The temperature may depend on the free radical source. If it is not a UV initiator type source, it may be preferable to operate at between 50°C and 95°C, more preferably between 60°C and 80°C. In general, the higher the temperature, the more easily the polymerization is initiated (it is accelerated), but the lower the molar mass of the resulting copolymer.

[0056] According to a preferred embodiment of the present invention, the polymer (P) is obtained by radical polymerization of one monomer (AA), one monomer (AM) and one monomer (M1) in the presence of a free radical source to obtain a polymer comprising repeating units derived from the monomer (AA), repeating units derived from the monomer (AM) and repeating units derived from the monomer (M1).

[0057] According to a more preferred embodiment, the polymer (P) is obtained by radical polymerization of acrylic acid, acrylamide and vinylimidazole of formula (IIa).

[0058] The polymer (P) can also be prepared by any controlled radical polymerization technique, among which reversible addition-fragmentation chain transfer (RAFT) and polymer design by interchange of xanthates (MADIX).

[0059] The use of RAFT or MADIX controlled radical polymerization agents (hereinafter referred to as "RAFT / MADIX agents") has been disclosed, for example, in WO 98 / 058974A (RHODIA CHIMIE), December 30, 1998, and WO 98 / 01478A (EIDUPONT DE NEMOURS AND COMMONWEALTH SCIENTIFIC AND INDUSTRIAL RESEARCH ORGANIZATION), January 15, 1998.

[0060] Preferably, the polymer (P) is obtained by radical copolymerization of a mixture having the following molar ratios, based on the total amount of monomers (AA), (AM) and additional monomers (M) selected from monomers (M1) and (M2): - monomers (AA): 0.1 to 95%, in particular 5 to 50%, preferably 20 to 40%, - Monomer (AM): 0.1 to 90%, preferably 25 to 90%, more preferably 60 to 80%, Monomer (M): 0.1 to 50%, for example 1 to 30%, in particular 1 to 20%, further in particular 2 to 15%.

[0061] Consequently, the polymer (P) is preferably - 0.1 to 95%, preferably 5 to 50%, preferably 20 to 40% of repeating units derived from monomer (AA), - 0.1 to 90%, preferably 25 to 90%, more preferably 50 to 80% of repeating units derived from the monomer (AM); - 1 to 50%, preferably 1 to 30%, more preferably 1 to 20%, and even more preferably 2 to 15% of repeating units derived from the monomer (M); Including, All of the foregoing mole percentages are based on the total moles of repeat units of the polymer (P).

[0062] In a preferred embodiment of the present invention, the polymer (P) is - 5 to 50%, preferably 20 to 40%, of repeat units derived from monomer (AA), - 25 to 90%, more preferably 50 to 80%, of repeating units derived from the monomer (AM); - 1 to 50%, for example 1 to 30%, in particular 1 to 20%, or even 2 to 15% of repeating units derived from the monomer (M); Including, All of the foregoing mole percentages are based on the total moles of repeat units of the polymer (P).

[0063] Typically, the preparation of the polymer (P) can be carried out in an adiabatic reactor to minimize heat exchange with the surroundings.

[0064] The polymer (P) can also be prepared by other means known to those skilled in the art, such as using a double-jacketed reactor equipped with an overhead mechanical stirrer and a thermostatic bath to control the reaction temperature to the desired profile.

[0065] The monomers and other reagents may be charged to the reactor all at once, so that they may be fed to the reactor using appropriate dosing devices to control the rate of polymerization.

[0066] Furthermore, the polymer (P) according to the present invention preferably has a number average molecular weight (Mn) of at least 90 kDa, for example 90 to 5000 kDa, preferably 850 kDa to 2000 kDa.

[0067] According to a preferred embodiment, the polymer (P) is a statistical (random) copolymer having a weight average molecular weight of about 100 kDa to 10,000 kDa, preferably 1,000 kDa to 3,000 kDa, and is prepared by radical polymerization of a mixture of monomers (AA), (AM) and (M), preferably at a concentration of about - 20-40% monomer (AA), - 50-80% monomer (AM), and - 2 to 15% monomer (M) The molar ratio is:

[0068] According to one embodiment of the present invention, the polymer (P) is a block copolymer obtained by controlled radical polymerization using a RAFT / MADIX agent.

[0069] As used herein, "block copolymer" refers to any controlled architecture copolymer, including, but not limited to, true block polymers, which may be diblock, triblock, or multiblock, also known as linear star polymers, comb, and gradient polymers. Gradient polymers are linear polymers in which the composition varies gradually along the polymer chain, and can range from random to blocky architecture. Each block of a block copolymer may itself be a homopolymer, random copolymer, random terpolymer, or gradient polymer.

[0070] The polymer (P) can be provided in a solid or dry form or in a vectorized form, such as a solution, emulsion, or suspension, particularly in the form of an aqueous solution. The vectorized form, such as an aqueous solution, can particularly contain 3 to 50% by weight, for example 5 to 30% by weight, of the polymer (P). The aqueous solution containing the polymer (P) can particularly be a solution obtained by the final aqueous phase preparation process of the radical polymerization process.

[0071] The polymer (P) may suitably be converted into its neutralized form (PN) and thus comprises repeat units derived from the neutralized form of the monomer (AA).

[0072] The polymer (PN) can be prepared by neutralizing the acid groups of the repeating units derived from the monomer (AA) defined above, the neutralization of the acid groups being carried out using a salt containing a monovalent cation [salt (S)], preferably an alkali metal salt, a suitable solvent or ammonia.

[0073] The salt (S) can be any salt capable of neutralizing an acid group. In some embodiments, the salt (S) is a lithium salt selected from the group consisting of lithium carbonate, lithium hydroxide, lithium bicarbonate, and combinations thereof, preferably lithium carbonate. In some embodiments, the lithium salt does not contain lithium hydroxide.

[0074] The solvent used in the step of neutralizing the polymer (PH) can be any solvent that can dissolve the salt (S) or ammonia and the resulting polymer (P). Preferably, the solvent is selected from at least one of water, NMP, and aqueous solvents such as alcohols, for example, methanol, isopropanol, and ethanol. Most preferably, the solvent is an aqueous solvent. Even more preferably, the solvent is water.

[0075] Preferably, the content of the salt (S) in the solvent is in the range of 0.5 to 10% by weight, preferably 1 to 5% by weight, based on the total weight of the solvent and the salt (S).

[0076] In some embodiments where the salt (S) is a lithium salt, the concentration of the lithium salt in the solvent provides at least 0.25, 0.5, 0.8, 1, 1.5, 2, 2.5, 3, 4 equivalents of lithium relative to the acid groups, hi some embodiments, the concentration of the lithium salt in the solvent provides at most 5, preferably at most 4 equivalents of lithium relative to the acid groups.

[0077] According to said embodiment, the polymer (P) comprises repeat units derived from the lithiated form of at least one α,β-ethylenically unsaturated carboxylic acid monomer.

[0078] The content of polymer (P) in the solution after neutralization is in the range of 0.5 to 40% by weight, preferably 2 to 30% by weight, more preferably 4 to 20% by weight, based on the total weight of the solvent and polymer (P).

[0079] The polymer (PN) is suitably isolated as a solid from the solution after neutralization and optionally stored for later use.

[0080] In a preferred embodiment, the lithium salt of polymer (P), i.e., polymer (P-Li), was prepared by adding an amount of LiOH to at least partially neutralize an aqueous solution containing about 10 wt. % polymer (P-Li). The resulting solution had a pH in the range of 6.5-9, preferably 7-8, and contained about 10 wt. % polymer (P-Li).

[0081] The advantage is that the salt form of the repeating unit derived from the monomer (AA) can avoid the trapping of lithium ions by free acid groups in the cell, which can reduce the first cycle coulombic efficiency and therefore the initial capacity.

[0082] All details of the process of the invention defined above and below in relation to the process involving the use of a polymer (P) also apply to the process in which (PN) is used.

[0083] Electrode active material (AM) For the purposes of the present invention, the term "electrode active material" is intended to mean a compound that is capable of incorporating or intercalating alkali or alkaline earth metal ions into its structure and subsequently releasing them during the charging and discharging stages of an electrochemical device. The electrode active material is preferably capable of incorporating or intercalating and releasing lithium ions.

[0084] The nature of the electrode active material (AM) varies depending on whether the composition is used to fabricate a negative electrode (anode) or a positive electrode (cathode).

[0085] When forming a positive electrode for a lithium-ion secondary battery, the electrode active material can include a composite metal chalcogenide of the formula LiMQ2 (where M is at least one metal selected from transition metals such as Co, Ni, Fe, Mn, Cr, and V, and Q is a chalcogen such as O or S). Among these, it is preferable to use a lithium-based composite metal oxide of the formula LiMO2 (where M is the same as defined above). Preferred examples of these include LiCoO2, LiNiO2, LiNi x Co 1-x O2 (0 < x < 1) and spinel-structured LiMn2O4 can be mentioned.

[0086] As an alternative form, when forming a positive electrode for a lithium-ion secondary battery, further, the electrode active material is of the formula M1M2(JO4) f E 1-f (where M1 is lithium and can be partially substituted by another alkali metal corresponding to less than 20% of the M1 metal, M2 is a transition metal at a +2 oxidation level selected from Fe, Mn, Ni, or a mixture thereof, and can be partially substituted by one or more additional metals at a +1 to +5 oxidation level corresponding to less than 35% of the M2 metal including 0, JO4 is an arbitrary oxyanion, J is any of P, S, V, Si, Nb, Mo, or a combination thereof, E is a fluoride, hydroxide, or chloride anion, and f is usually the molar fraction of the JO4 oxyanion included in the range of 0.75 to 1) of a lithiated or partially lithiated transition metal oxyanion-based electroactive material.

[0087] M1M2(JO4) defined above f E 1-f The electrode active material is preferably phosphate-based and can have an ordered or modified olivine structure.

[0088] More preferably, when forming the positive electrode, the electrode active material is of the formula Li 3-x M’ y M’’ 2-y(JO4)3 (where 0 ≦ x ≦ 3, 0 ≦ y ≦ 2, M’ and M’’ are the same or different metals, and at least one of them is a transition metal, JO4 is preferably PO4 which may be partially substituted by another oxyanion, and J is any one of S, V, Si, Nb, Mo or a combination thereof). Even more preferably, the electrode active material is a phosphate-based electroactive material of the formula Li(Fe x Mn 1-x )PO4 (where 0 ≦ x ≦ 1), such as lithium iron phosphate (LFP), lithium iron manganese phosphate (LMFP), and lithium manganese phosphate.

[0089] As a further alternative, when similarly forming a positive electrode for a lithium-ion secondary battery, the electrode active material is garnet-type inorganic particles of Li7La3Zr2O 12 (LLZO), or the general formula Li x La y Zr z A w O 12 (where - A represents one or more dopants selected from the group consisting of Al, Ga, Nb, Fe, Nd, Pt, Ta, W, Mo, Hf, Si, Ca, Sr, Ba, Ge and mixtures thereof, preferably from the group consisting of Al, Ga, Nb, Fe, Nd, Pt, Ta, W and mixtures thereof, more preferably from the group consisting of Al, Ga, W and mixtures thereof, - w, x, y and z are positive numbers including various combinations of integers and fractions or decimals, - 0 < y ≦ 3, preferably 2 ≦ y ≦ 3, preferably 2.5 ≦ y ≦ 3, - 0 < z ≦ 2, preferably 1 < z ≦ 2, preferably 1.5 ≦ z ≦ 2, - 0 ≦ w ≦ 0.5, preferably 0 ≦ w ≦ 0.35, more preferably 0 ≦ w ≦ 0.25, - x is derived from the electrical neutrality of the garnet structure) doped LLZO inorganic particles having, and combinations thereof may be included.

[0090] When forming a negative electrode for a lithium ion secondary battery, the electrode active material may preferably comprise a material selected from the group consisting of one or more carbon-based materials and one or more silicon-based materials.

[0091] In some embodiments, the carbon-based material may be selected from graphite, such as natural or artificial graphite, graphene, or carbon black.

[0092] These materials may be used alone or as a mixture of two or more thereof.

[0093] The carbon-based material is preferably graphite.

[0094] The silicon-based compound may be one or more selected from the group consisting of chlorosilanes, alkoxysilanes, aminosilanes, fluoroalkylsilanes, silicon, silicon chloride, silicon carbide, and silicon oxide.

[0095] More specifically, the silicon-based compound may be silicon oxide or silicon carbide.

[0096] Silicon oxides include, in particular, lithiated materials for forming Li4SiO4 and Li2SO3, as disclosed in WO 2015 / 063979, having the formula SiO x Particles having (0.5≦x≦1) may be included.

[0097] When present in the electrode active material, the silicon-based compound is included in an amount ranging from 1 to 60% by weight, preferably from 5 to 30% by weight, based on the total weight of the electroactive compound.

[0098] Composition (C) may further comprise one or more optional conductivity-imparting additives that may be added to improve the conductivity of the resulting electrode made from composition (C) of the present invention.

[0099] Conductive agents for batteries are known in the art.

[0100] Examples may include carbon-based materials such as carbon black, graphite fine powder, carbon nanotubes, graphene or fibers, or fine powders or fibers of metals such as nickel or aluminum. The optional conductive agent is preferably carbon black. Carbon black is available, for example, under the brand names Super P® or Ketjenblack®.

[0101] If present, the conductive agent is different from the carbon-based material described above.

[0102] The amount of the optional conductive agent is preferably 0 to 30 wt % of the total solid content in the electrode-forming composition. In particular, in the case of a cathode-forming composition, the amount of the optional conductive agent is typically 0 to 10 wt %, more preferably 0 to 5 wt %, of the total solid content in the composition.

[0103] For anode-forming compositions that do not include a silicon-based electroactive compound, the optional conductive agent is typically present in an amount of from 0 wt. % to 5 wt. %, more preferably from 0 wt. % to 2 wt. %, of the total amount of solids in the composition, while for anode-forming compositions that include a silicon-based electroactive compound, it has been found beneficial to incorporate a larger amount of optional conductive agent, typically from 0.5 to 30 wt. % of the total amount of solids in the composition.

[0104] In step ii) of the method of the present invention, mixing the electrode active material (AM), the polymer (P) defined above, and the optional at least one conductive agent is carried out by dry mixing these components without adding solvents, liquids, processing aids, etc. to the particle mixture. Dry mixing can be carried out, for example, in a mill, mixer, or blender (such as a V-blender equipped with a high-strength stirring rod or other alternative equipment as further described below) until a uniform dry mixture is formed. Those skilled in the art will recognize, after reading this specification, that mixing times may vary based on batch size, materials, particle size, density, and other properties and still remain within the scope of the present invention.

[0105] In step iii) of the process of the present invention, the powdery dry mixture obtained in step ii) is subjected to a mechanical compression step to obtain a self-supporting dry film.

[0106] The compaction of the dry mixture obtained in step ii) can be carried out as a mechanical compaction, for example by means of a roller compactor or a tablet press, but it may also be carried out as a rolling, build-up or by any other technique suitable for this purpose.

[0107] The mechanical compression step may be associated with a thermal consolidation step. The combination of pressure and heat treatment allows for thermal consolidation at a lower temperature than if it were carried out alone.

[0108] In one embodiment, the mechanical compaction step is carried out by pressing, suitably by pressing the dry mixture obtained in step ii) between two metal foils. Preferably, the mechanical compaction step is carried out by applying a compaction pressure of 5 to 50 MPa, preferably 10 to 30 MPa.

[0109] The compression step is conveniently carried out at a temperature of not more than 200°C, preferably below 180°C.

[0110] In step iv), the dry film obtained in step iii) is applied onto a conductive substrate to form an electrode.

[0111] The sheet of substrate material may comprise a metal foil, particularly an aluminum foil.

[0112] Due to the improved adhesion of composition (C), the dry film obtained in step iii) can be applied onto a conductive substrate without the need for a primer or an adhesive layer.

[0113] Steps i) through iv) can be performed as a single step or as separate steps, and some of the steps can be functionally separated and / or combined during the implementation of some embodiments.

[0114] The polymer (P) can be conveniently used as the sole binder in the manufacture of electrodes according to the method of the present invention or can be used in a blend with PTFE.

[0115] Therefore, according to another aspect of the present invention, there is provided a method for producing an electrode for an electrochemical cell [electrode (E1)], comprising the steps of: step I) combining polytetrafluoroethylene (PTFE) with the polymer (P) defined above to provide a binder (B); - step II) dry-mixing, in the absence of a solvent, at least one electrode active material (AM), a binder (B) as defined above, and optionally at least one conductive agent to provide a dry electrode-forming composition [composition (C)]; - step III) feeding the composition (C1) obtained in step II) into a press to form a self-supporting dry film; and Step IV) applying the dry film to a conductive substrate to form an electrode. A method is provided that includes:

[0116] In the context of the present invention, the term "PTFE" means a polymer obtained from the polymerization of tetrafluoroethylene (TFE).

[0117] However, the PTFE polymer may also contain small amounts of one or more comonomers, such as, but not limited to, hexafluoropropylene, perfluoro(methyl vinyl ether), perfluoro(propyl vinyl ether), and perfluoro-(2,2-dimethyl-1,3-dioxole), provided that the latter do not significantly adversely affect the inherent properties of the tetrafluoroethylene homopolymer, such as its thermal and chemical stability. Preferably, the amount of such comonomers does not exceed about 3 mol%, more preferably less than about 1 mol%; a comonomer content of less than 0.5 mol% is particularly preferred. When the total comonomer content is greater than 0.5 mol%, the amount of perfluoro(alkyl vinyl ether) comonomer is preferably less than about 0.5 mol%. PTFE homopolymers are most preferred.

[0118] PTFE suitable for use in preparing the binder (B) of the present invention is in powder form.

[0119] PTFE in powder form can be obtained by solidifying a PTFE lattice by cryogenic solidification or by electrolytic solidification with the addition of an electrolyte. See, for example, U.S. Patent No. 6,790,932. Preferred examples of electrolytes are: - Aluminum sulfate (Al2(SO4)3) at a concentration of 2 g / l calculated based on the amount of water in the coagulation vessel, - Ammonium carbonate ((NH4)2CO3) at a concentration of 8 g / l calculated based on the amount of water in the coagulation vessel, or - Nitric acid (HNO3), 25 ml of a 65% solution calculated based on the amount of water in the coagulation vessel.

[0120] Alternatively, the PTFE powder may be obtained from a PTFE lattice in the form of a gel by coagulation with an electrolyte as described above. The gel may be obtained according to US Patent Nos. 6,790,932 and 6,780,966.

[0121] After coagulation has taken place, the polymer is washed with demineralized water at room temperature. After coagulation and washing, the PTFE powder obtained therefrom is then dried.

[0122] PTFE in powder form generally has a particle size of 1 to 1600 microns, preferably 100 to 800 microns, and more preferably 400 to 700 microns.

[0123] Typically, the weight ratio of PTFE / polymer (P) will be between 95 / 5 wt / wt and 5 / 95 wt / wt. Those skilled in the art will select the most appropriate weight ratio taking into account the target final properties of the binder (B).

[0124] In particular, when a binder (B) is used to prepare the negative electrode, the weight ratio of PTFE / polymer (P) is advantageously comprised within the range of 50 / 50 wt / wt to 5 / 95 wt / wt.

[0125] In one preferred embodiment, the weight ratio of PTFE / polymer (P) in binder (B) for use in making the negative electrode is 20 / 80 wt / wt, which provides a negative electrode with surprisingly improved capacity.

[0126] The Applicant has surprisingly found that the amount of polymer (P) added to PTFE does not affect the ability to fibrillate the PTFE.

[0127] The amount of binder (B) that can be used in composition (C1) is influenced by various factors. One such factor is the surface area and amount of the active material and the surface area and amount of the conductivity-imparting additive added to the electrode-forming composition. These factors are believed to be important because the binder particles provide a bridge between the conductive material particles, keeping them in contact.

[0128] Composition (C1) comprises one or more electrode active materials (AM) as defined above.

[0129] The dry blending step II) fibrillates the binder particles to produce fibrils that ultimately form the matrix supporting the resulting composition of matter. The resulting dough-like material can be calendered multiple times to produce a conductive film of desired thickness and density. Blending can be provided by subjecting the mixture to an extruder.

[0130] The same details provided above for steps i) to iv) apply to steps I) to IV), respectively.

[0131] Steps I)-IV) can be performed as a single step or as separate steps, and some of the steps can be functionally separated and / or combined during the implementation of some embodiments.

[0132] Composition (C) or composition (C1) obtained in step ii) or step II) of the process according to the invention may further comprise at least one sulfide-based solid electrolyte.

[0133] When the composition (C) or the composition (C1) used in the process according to the invention comprises at least one sulfide-based solid electrolyte or at least one solid electrolyte based on garnet-type inorganic particles, the present invention provides an electrode suitable for use in a solid-state battery [electrode (ESS)] obtained by the process defined above.

[0134] Thus, in one embodiment, the present invention provides a method for producing an electrode for a solid state battery (ESS), comprising: a) providing a polymer (P) as defined above; -b) dry-mixing, in the absence of a solvent, at least one electrode active material (AM), the polymer (P) provided in step i) defined above, at least one sulfide-based solid electrolyte or at least one garnet-type inorganic particle-based solid electrolyte, and optionally at least one conductive agent to provide a dry electrode-forming composition [composition (C')]; -c) feeding the composition (C') obtained in step ii) into a press to form a self-supporting dry film; and -d) applying the dry film to a conductive substrate to form an electrode. The present invention provides a method comprising:

[0135] The same details provided above for steps i) to iv) apply to steps a) to d), respectively.

[0136] In another aspect, the present invention provides a method for producing an electrode for a solid-state battery [Electrode (ESS-1)], comprising: step I') combining polytetrafluoroethylene (PTFE) with the polymer (P) defined above to provide a binder (B); - step II') dry-mixing, in the absence of a solvent, at least one electrode active material (AM), a binder (B) as defined above, at least one sulfide-based solid electrolyte, and optionally at least one conductive agent to provide a dry electrode-forming composition [composition (C1')]; - step III') feeding the composition (C1') obtained in step ii) into a press to form a self-supporting dry film; and - Step IV') Applying the dry film to a conductive substrate to form an electrode The present invention provides a method comprising:

[0137] The same details provided above for steps i) to iv) apply to steps I') to IV'), respectively.

[0138] As used herein, the phrase "sulfide-based solid electrolyte" refers to a Li + Refers to inorganic solid-state materials that conduct ions but are substantially electronically insulating.

[0139] In the present invention, the term "sulfide-based solid ionically conductive inorganic particles" is not particularly limited as long as it is a solid electrolyte material containing sulfur atoms in its molecular structure or composition.

[0140] The sulfide-based solid, ionically conductive inorganic particles preferably contain Li, S, and an element of Groups 13 to 15, such as P, Si, Sn, Ge, Al, As, Sb, or B, in order to increase Li-ion conductivity.

[0141] The sulfide-based solid, ionically conductive inorganic particles according to the present invention are preferably selected from the group consisting of: - Li 10 SnP2S 12 Lithium tin phosphorus sulfide ("LSPS") materials such as; - Formula (Li2S) x -(P2S5) y where x+y=1 and 0≦x≦1, Li7P3S 11 , Li7PS6, Li4P2S6, Li 9.6 P3S 12 and lithium phosphosulfide ("LPS") materials such as glasses, crystals, or glass-ceramics of the type Li3PS4; - Li2CuPS4, Li 1+2x Zn 1-x PS4 (wherein 0≦x≦1), Li 3.33 Mg 0.33 P2S6 and Li 4-3x Sc x doped LPS such as P2S6 (where 0≦x≦1); - Expression Li x P y S z Lithium Phosphorus Sulfide Oxygen (“LPSO”) material of formula O, where 0.33≦x≦0.67, 0.07≦y≦0.2, and 0.4≦z≦0.55; - Li 10 SnP2S 12、 Li 10 GeP2S 12, Li 10 SiP2S 12 , and lithium phosphorus sulfide materials with X being Si, Ge, Sn, As, or Al, such as Li2S-P2S5-SnS ("LXPS"); - Lithium Phosphorus Sulfide Oxygen ("LXPSO"), with X being Si, Ge, Sn, As, or Al; - Li2SiS3, Li2S-P2S5-SiS2, Li2S-P2S5-SiS2-LiCl, Li2S-SiS2-P2S5, Li2S-SiS2-P2S5-LiI, Li2S-SiS2-LiI, Li2S-SiS2, Li 9.54 Si 1.74 P 1.44 S 11.7 Cl 0.3 and lithium silicon sulfide ("LSS") materials, such as Li2S-SiS2-Al2S3; - Lithium borosulfide materials such as Li3BS3 and Li2S-B2S3-LiI; - Li 0.8 Sn 0.8 S 2、 Li4SnS4, Li 3.833 Sn 0.833 As 0.166 Lithium tin sulfide and lithium arsenide materials such as S4, Li3AsS4-Li4SnS4 and Ge-substituted Li3AsS4; - General formula Li a PS b X c (wherein X represents at least one halogen element selected from the group consisting of Cl, Br, and I or a combination thereof; a represents a number from 2.0 to 7.0; b represents a number from 3.5 to 6.0; and c represents a number from 0 to 3.0), such as Li4PS4Cl 、 Li7P2S8Cl, and Li7P2S8I.

[0142] In a more preferred embodiment, the sulfide-based solid, ionically conductive inorganic particles have the general formula Li a PS b X c and more specifically, argyrodite-type sulfide-based materials of the formula Li6PS5X (wherein X is Cl, Br, or I).

[0143] In another preferred embodiment, the argyrodite-type sulfide-based material of formula Li6PS5Y is, for example, Li 6-x PS 5-x Cl 1+x(0≦x≦5) or are sulfur and / or lithium deficient or doped with heteroatoms.

[0144] Particularly preferred sulfide solid electrolytes are LPS materials, LSPS materials and argyrogenite-type sulfide materials.

[0145] The electrode (E), electrode (E1) and electrode (ESS) of the present invention are particularly suitable for use in electrochemical devices, especially secondary batteries.

[0146] In one aspect, the present invention provides an electrochemical device that is a secondary battery, the secondary battery comprising: -Positive and negative electrodes Including, Here, at least one of the positive electrode and the negative electrode is the electrode (E), (E1) or (ESS) according to the present invention.

[0147] In a further object, the present invention provides a solid-state battery comprising a composite solid electrolyte membrane, a positive electrode, and a negative electrode, A solid-state battery is provided in which at least one of the negative electrode or the positive electrode is an electrode (ESS) according to the present invention.

[0148] The secondary battery of the present invention is preferably an alkaline secondary battery or an alkaline earth secondary battery.

[0149] The secondary battery of the present invention is more preferably a lithium ion secondary battery.

[0150] Electrochemical devices according to the present invention can be prepared by standard methods known to those skilled in the art.

[0151] To the extent that the disclosure of any patents, patent applications, and publications incorporated herein by reference contradicts the statements of this application to the extent that a term may be unclear, the statements of this application shall control.

[0152] The present invention will now be described with reference to the following examples, the purposes of which are merely illustrative and are not intended to limit the scope of the invention. [Example]

[0153] Materials and Methods silicon oxide, commercially available from Shin-Etsu Chemical Co., Ltd., KSC-1064, theoretical capacity approximately 2100 mAh / g; graphite, GHDR 15-4 commercially available from Imerys SA; carbon black, commercially available as SC45 from Imerys SA; carbon black, commercially available as SC65 from Imerys SA; PTFE: PTFE homopolymer powder having a specific gravity of 2160, measured in accordance with ASTM D792, and a rheometric pressure of 9.50 MPa, measured in accordance with ASTM D4895; Lithium iron phosphate, LFP, available as Life Power manufactured by Johnson Matthey; Galden HT80, commercially available from Solvay Materials; AA: acrylic acid available from Aldrich; AM: Acrylamide monomer (50% aqueous solution) available from SNF; VIm: vinylimidazole monomer available from Aldrich.

[0154] Synthesis of AA-AM-VIm terpolymer (polymer P1) The synthesis process was carried out in a thermally isolated reactor (Thermos-like flask) to minimize heat exchange with the surroundings.

[0155] The reactor was equipped with a small reflux system, a mechanical stirring system, a nitrogen purge line, and a lid containing multiple inlets to which raw material feed lines were attached.

[0156] In the first step, all the monomers (117.8 g AA, 478.5 g AM, 18 g VIm), solvent (871.6 g water), and transfer agent were charged to a reactor and maintained at room temperature for approximately 1 hour under stirring and nitrogen purging. The redox-type initiator was then added to the reaction mixture. A thermal initiator was also added to the reaction mixture at the same time. The initiator was homogenized in the reaction mixture with mechanical stirring for several minutes, and then the stirring and nitrogen purging were stopped.

[0157] An exothermic effect occurred within about 30 minutes to 1 hour, raising the temperature of the reaction mixture from room temperature to about 80-90° C. The reaction mixture was then maintained in the reaction flask for an additional 24 hours.

[0158] The resulting polymer has a Mw of 1400 kDa as determined by GPC.

[0159] Preparation of polymer P1 powder: Powder of polymer P1 obtained as detailed above was prepared by oven drying the polymer solution followed by grinding in a Retsch RM200 type mortar grinder according to the following procedure.

[0160] 50 g of an aqueous solution of polymer P1 (polymer content 7%) was dried in an oven at 70°C for 12 hours to remove moisture. The resulting polymer mass was then ground into a fine powder by using an automatic mortar for a total of 20 minutes.

[0161] Polymer Blending: The powders of polymer P1 and PTFE were mixed by hand in powder form in ratios of 1:1 and 4:1.

[0162] Film preparation 7 g of a powder mixture of polymer P1 and PTFE was ground in a stainless steel automatic mortar for 8 minutes with the addition of 5 mL of Galden as a lubricant. The resulting prefilm was manually manipulated to fibrillate the polymer and obtain a fully bonded, free-standing film. The film was calendered to reduce the thickness to less than 200 μm.

[0163] Lamination with metal substrate The film obtained as detailed above was placed between two pieces of aluminum foil and preheated in a press for 10 minutes at 150° C. Then, 160 bar was applied for 10 minutes to laminate the film to the aluminum foil at a temperature of 150° C. and a pressure of 160 bar. The press was then allowed to cool to room temperature without releasing the pressure.

[0164] The same procedure was carried out using two copper foils instead of the aluminum foil.

[0165] Adhesion evaluation and measurement Adhesion evaluation and measurements were carried out between the samples laminated as described above and the foils in the three-layer structure (metal foil / film / metal foil) obtained after lamination according to ASTM D 1876. The adhesion levels are reported in Table 1 below. No adhesion was observed for the PTFE powder when used alone in the preparation of films by compression, neither between two aluminum foils nor between two copper foils.

[0166] Peel strength was evaluated based on the following criteria: A higher value for peel strength indicates better intimate adhesion between the polymer and the current collector.

[0167] [Table 1]

[0168] Example 1: LFP electrode preparation composition of polymer (P1) and PTFE A dry mixture of 6.48 g of LFP and 0.36 g of SC65 was prepared by grinding the powders in an electric mortar for 10 minutes.

[0169] 4 ml of Galden was added as a lubricant to the powder mixture, and the composite was mixed in an electric mortar for 1 minute to obtain a homogeneous paste.

[0170] 0.18 g of polymer P1 powder and 0.18 g of PTFE were added to the homogeneous paste along with 3 ml of Galden as a lubricant and mixed in a mortar and pestle mill for 5 minutes to obtain a homogeneous composite.

[0171] The composite was then manually manipulated to fibrillate the polymer and obtain an overall bonded free-standing film.

[0172] The film was calendered to reduce the thickness to less than 200 μm.

[0173] The resulting positive electrode had the following composition by weight: 90% LFP, 2.5% polymer P1, 2.5% PTFE and 5% carbon black.

[0174] Thus, the electrode EC1 was obtained.

[0175] The EC1 sample was placed between two aluminum current collectors and preheated in a press at 150° C. for 10 minutes. 160 bar was then applied for 10 minutes to laminate the EC1 to the current collectors at a temperature of 150° C. and a pressure of 160 bar. The press was then allowed to cool to room temperature without releasing the pressure.

[0176] An electrode laminated on an Al current collector is obtained.

[0177] Example 2: Graphite / Silicon Electrode Fabrication Composition with 1:1 Polymer P1 to PTFE A dry mixture of 5.41 g of graphite, 1.36 g of silicon, and 0.072 g of SC45 was prepared by grinding the powders in an electric mortar for 10 minutes.

[0178] 5 ml of Galden was added as a lubricant to the powder mixture, and the composite was mixed in an electric mortar for 1 minute to obtain a homogeneous paste.

[0179] 0.18 g of polymer P1 powder and 0.18 g of PTFE were added to the homogeneous paste along with 4 ml of Galden as a lubricant and mixed in a mortar and pestle mill for 5 minutes to obtain a homogeneous composite.

[0180] The composite was then manually manipulated to fibrillate the polymer and obtain an overall bonded free-standing film.

[0181] The film was calendered to reduce the thickness to less than 200 μm.

[0182] The resulting negative electrode had the following composition by weight: 75.2% graphite, 18.8% silicon, 2.5% polymer P1, 2.5% PTFE and 1% carbon black.

[0183] Thus, electrode EC2 was obtained.

[0184] The EC2 sample was placed between two aluminum current collectors and preheated in a press at 150° C. for 10 minutes. 160 bar was then applied for 10 minutes to laminate the EC2 to the current collectors at a temperature of 150° C. and a pressure of 160 bar. The press was then allowed to cool to room temperature without releasing the pressure.

[0185] An electrode laminated onto a Cu current collector is obtained.

[0186] Example 3: Graphite / Silicon Electrode Fabrication Composition of Polymer P1 A dry mixture of 3.82 g of graphite, 0.95 g of silicon, and 0.050 g of SC45 was prepared by grinding the powders in an electric mortar for 10 minutes.

[0187] 2.38 g of polymer P1 powder was added to the powder and mixed in a mortar grinder for 5 minutes to obtain a uniform distribution.

[0188] The powder was spread between two copper current collectors and preheated in a press at 150° C. for 10 minutes. EC3 was then laminated to the current collectors at a temperature of 150° C. and a pressure of 160 bar, with 160 bar applied for 10 minutes. The press was then allowed to cool to room temperature without releasing the pressure.

[0189] An electrode laminated onto a Cu current collector is obtained.

[0190] The resulting negative electrode had the following composition by weight: 53% graphite, 13.3% silicon, 33% polymer P1 and 0.71% carbon black.

[0191] Thus, sample EC3 was obtained.

[0192] Example 4: Graphite / Silicon Electrode Fabrication Composition with Polymer P1 to PTFE 4:1 A dry mixture of 5.41 g of graphite, 1.36 g of silicon, and 0.072 g of SC45 was prepared by grinding the powders in an electric mortar for 10 minutes.

[0193] 5 ml of Galden was added to the powder mixture and the complex was mixed in an electric mortar for 1 minute to obtain a homogeneous paste.

[0194] 0.288 g of polymer (A) powder and 0.072 g of PTFE were added to the homogeneous paste along with 4 ml of Galden and mixed in a mortar and pestle mill for 5 minutes to obtain a homogeneous composite.

[0195] The composite was then manually manipulated to fibrillate the polymer and obtain an overall bonded free-standing film.

[0196] The film was calendered to reduce the thickness to less than 200 μm.

[0197] The resulting negative electrode had the following composition: 75.2% by weight of graphite, 18.8% by weight of silicon, 2.5% by weight of polymer (A), 2.5% by weight of PTFE and 1% by weight of carbon black.

[0198] Thus, electrode EC4 was obtained.

[0199] The EC4 sample was placed between two copper current collectors and preheated in a press at 150° C. for 10 minutes. 160 bar was then applied for 10 minutes to laminate the EC4 to the current collectors at a temperature of 150° C. and a pressure of 160 bar. The press was then allowed to cool to room temperature without releasing the pressure.

[0200] Comparative Example 1: Preparation of LFP electrodes using PTFE A dry mixture of 6.48 g of LFP and 0.36 g of SC65 was prepared by grinding the powders in an electric mortar for 10 minutes.

[0201] 4 ml of Galden was added as a lubricant to the powder mixture, and the composite was mixed in an electric mortar for 1 minute to obtain a homogeneous paste.

[0202] 0.36 g of PTFE was added to the homogeneous paste along with 3 ml of Galden as a lubricant and mixed in a mortar and pestle mill for 5 minutes to obtain a homogeneous composite.

[0203] The composite was then manually manipulated to fibrillate the polymer and obtain an overall bonded free-standing film.

[0204] The film was calendered to reduce the thickness to less than 200 μm.

[0205] The resulting positive electrode had the following composition: 90% by weight LFP, 5% by weight PTFE and 5% by weight carbon black.

[0206] In this way, the electrode CE1 was obtained.

[0207] The CE1 sample was placed between two aluminum current collectors and preheated in a press at 150° C. for 10 minutes. 160 bar was then applied for 10 minutes to laminate the CE1 to the current collectors at a temperature of 150° C. and a pressure of 160 bar. The press was then allowed to cool to room temperature without releasing the pressure.

[0208] No lamination of the electrodes with aluminum is obtained.

[0209] Comparative Example 2: Preparation of graphite / silicon electrodes using PTFE A dry mixture of 5.41 g of graphite, 1.36 g of silicon, and 0.072 g of SC45 was prepared by grinding the powders in an electric mortar for 10 minutes.

[0210] 5 ml of Galden was added as a lubricant to the powder mixture, and the composite was mixed in an electric mortar for 1 minute to obtain a homogeneous paste.

[0211] 0.36 g of PTFE was added to the homogeneous paste along with 4 ml of Galden as a lubricant and mixed in a mortar and pestle mill for 5 minutes to obtain a homogeneous composite.

[0212] The composite was then manually manipulated to fibrillate the polymer and obtain an overall bonded free-standing film.

[0213] The film was calendered to reduce the thickness to less than 200 μm.

[0214] The resulting negative electrode had the following composition by weight: 75.2% graphite, 18.8% silicon, 5% PTFE and 1% carbon black.

[0215] In this way, the electrode CE2 was obtained.

[0216] The EC2 sample was placed between two copper current collectors and preheated in a press at 150° C. for 10 minutes. 160 bar was then applied for 10 minutes to laminate the CE2 to the current collectors at a temperature of 150° C. and a pressure of 160 bar. The press was then allowed to cool to room temperature without releasing the pressure.

[0217] No lamination of the electrodes with copper is obtained.

[0218] Adhesion of electrode compositions to current collectors: evaluation and measurement Adhesion evaluation and measurement was carried out between the electrode composition obtained above and copper or aluminum foil in the three-layer structure (metal foil / film / metal foil) obtained after lamination according to ASTM D 1876. The adhesion values ​​are reported in Table 2. No adhesion was observed for CE1 and CE2.

[0219] The peel strength was evaluated based on the following criteria: A higher value for the peel strength indicates better intimate adhesion between the negative electrode mixed material layer and the current collector. A: Peel strength of at least 2.0 N / m B: Peel strength of at least 0.1 N / m and less than 2.0 N / m C: Adhesion was achieved, but was difficult to measure due to sample stiffness D: No adhesion

[0220] [Table 2]

[0221] Electrical Resistance Measurement The electrical resistance of EC1, EC2, CE1, and CE2 was measured using a Keithley Multimeter. A 20 mm diameter disk from the sample was pressed between two 10 mm diameter electrodes connected to the Keithley with a dynamometer applying a force of 50 N for 1 minute, after which the resistance was recorded. The average resistance of the two samples, calculated as the average of three repeated measurements, is reported in Table 3 below. The values ​​are similar for both compositions.

[0222] [Table 3]

[0223] The data show that the binders of the present invention have improved adhesion to current collectors while retaining good conductive properties, making them suitable for use as binders for electrodes.

[0224] Cyclic voltammetry evaluation To evaluate different binder ratios, cyclic voltammetry was performed on samples EC2 and EC4. Tests were performed in coin cells with a lithium-to-negative electrode configuration from 3 to 0.01 V at a sweep rate of 10 mV / s. 1 M LiPF6 in 1:1 vol / vol EC:DMC was used as the electrolyte. Table 4 contains data on peak position and height for the first cycle.

[0225] [Table 4]

[0226] The results show that very good electrochemical behavior is maintained when the PTFE content is reduced: the peak positions remain unchanged and the extracted current does not decrease.

Claims

1. i) providing a polymer (P), the polymer (P) comprising: (A) a repeating unit derived from at least one α,β-ethylenically unsaturated carboxylic acid monomer [monomer (AA)]; (B) Formula (I): 【Chemical 1】 (In the formula, R ５ represents a hydrogen atom or a methyl group, R ６ and R ７ are the same or different and may be selected from a hydrogen atom or a linear or branched alkyl group having 1 to 6 carbon atoms; R ８ and R ９ may be the same or different and may be selected from the group consisting of a hydrogen atom, a linear or branched alkyl group having 1 to 6 carbon atoms, a carboxyl group, and an amide group. and a repeating unit derived from at least one (meth)acrylamide monomer [monomer (AM)] of the formula: (C) optionally, a repeating unit derived from at least one monomer (M) selected from the group consisting of monomers (M1) and (M2), the monomer (M1) has the following formula (II): 【Chemistry 2】 (In the formula, R １ is H or an alkyl group, the alkyl group being preferably a methyl group; R ２ is H or an alkyl group, R ３ and R ４ are the same or different and may be selected from a hydrogen atom or a linear or branched alkyl group having 1 to 6 carbon atoms; A is, a single covalent bond, and - Spacer is a bond selected from the group consisting of X, Y and Z are independently selected from carbon atoms or nitrogen atoms; a, b and c are independently selected from the integers 1 to 2; Each dashed dotted line represents an optional double bond. an ethylenically unsaturated monomer having an unsaturated heterocyclic group having at least one nitrogen atom, the monomer (M2) is different from the monomers (AA) and (AM) and has the following formula (III): 【Chemistry 3】 (In the formula, R ｉ is H, -COOH, -CH ２ COOH or an alkyl group, the alkyl group being preferably a methyl group; R ｉｉ and R ｉｉｉ are the same or different and may be selected from a hydrogen atom or a linear or branched alkyl group having 1 to 6 carbon atoms, or may be a —COOH group; B is a bond selected from the group consisting of a —C(O)—O— group and a —C(O)—NH— group; R ｘ is a hydrogen atom, an ether (—O—), a heterocyclic group, a sulfonic acid group (—SO ３ H), salts of sulfonic acid groups (-SO ３ Cat), phosphonic acid group (-PO ３ H ２ ), a salt of a phosphonic acid group (—PO ３ Cat ２ ), phosphate group (-OPO ３ H ２ ) and salts of phosphate groups (-OPO ３ Cat ２ ) a linear or branched C containing at least one functional group selected from the group consisting of ３ ~C ２０ Cat is preferably a monovalent cation selected from alkali metal cations, more preferably Na ＋ , K. ＋ and Li ＋ (selected from and a repeating unit having a process comprising: -ii) dry-mixing, in the absence of a solvent, at least one electrode active material (AM), the polymer (P) provided in step i) as defined above, and optionally at least one conductive agent to obtain a dry electrode-forming composition [composition (C)]; -iii) feeding the composition (C) obtained in step ii) into a press to form a self-supporting dry film; and -iv) applying the dry film to a conductive substrate to form an electrode; A method for producing an electrode [electrode (E)] for an electrochemical cell, comprising, or preferably consisting of,

2. The monomer (AA) is represented by the formula (IV): 【Chemistry 4】 (In the formula, R ４ , R ５ and R ６ are the same or different from each other, and are a hydrogen atom and C １ ~C ３ independently selected from hydrocarbon groups The method of claim 1, wherein the compound is

3. 2. The method according to claim 1, wherein the monomer (AM) of formula (I) is selected from the group consisting of meth(acryl)amide or N-substituted meth(acryl)amide, such as N-alkylacrylamide, N,N-dialkylacrylamide.

4. The monomer (M1) is Formula (IIa): 【Chemistry 5】 vinylimidazole (VIm) Formula (IIb) 【Chemistry 6】 2-methyl-1-vinylimidazole Formula (IIc) 【Chemistry 7】 1-vinyl-1,2,4-triazole Formula (IId) 【Chemistry 8】 2-vinylpyrazine Formula (IIe) 【Chemistry 9】 of 4-vinylpyridine Formula (IIf) 【Chemistry 10】 of 2-vinylpyridine Formula (IIg) 【Chemistry 11】 Hydroxyl-(meth)acrylate imidazole derivatives of 2. The method of claim 1, wherein the compound is selected from the group consisting of:

5. The polymer (P) is - 0.1 to 95%, preferably 5 to 50%, more preferably 20 to 40% of repeat units derived from monomer (AA), - 0.1 to 90%, preferably 25 to 90%, more preferably 50 to 80% of repeat units derived from monomer (AM), - 1 to 50%, preferably 1 to 30%, more preferably 1 to 20%, even more preferably 2 to 15% of repeating units derived from the monomer (M); Including, wherein at least one of the monomers (AA) and (AM) is present in an amount other than 0%; All of the foregoing mole percentages are based on the total number of moles of repeat units of polymer (P). The method according to any one of claims 1 to 4.

6. The method of any one of claims 1 to 5, wherein composition (C) further comprises one or more conductivity-imparting additives.

7. An electrode (E) for a secondary battery obtainable by the method according to any one of claims 1 to 6.

8. step I) combining polytetrafluoroethylene (PTFE) with a polymer (P) to provide a binder (B), wherein the polymer (P) is (A) a repeating unit derived from at least one α,β-ethylenically unsaturated carboxylic acid monomer [monomer (AA)]; (B) Formula (I): 【Chemistry 12】 (In the formula, R ５ represents a hydrogen atom or a methyl group, R ６ and R ７ are the same or different and may be selected from a hydrogen atom or a linear or branched alkyl group having 1 to 6 carbon atoms; R ８ and R ９ may be the same or different and may be selected from the group consisting of a hydrogen atom, a linear or branched alkyl group having 1 to 6 carbon atoms, a carboxyl group, and an amide group. and a repeating unit derived from at least one (meth)acrylamide monomer [monomer (AM)] of the formula: (C) optionally, a repeating unit derived from at least one monomer (M) selected from the group consisting of monomers (M1) and (M2), the monomer (M1) has the following formula (II): 【Chemistry 13】 (In the formula, R １ is H or an alkyl group, the alkyl group being preferably a methyl group; R ２ is H or an alkyl group, R ３ and R ４ are the same or different and may be selected from a hydrogen atom or a linear or branched alkyl group having 1 to 6 carbon atoms; A is, a single covalent bond, and - Spacer is a bond selected from the group consisting of X, Y and Z are independently selected from carbon atoms or nitrogen atoms; a, b and c are independently selected from the integers 1 to 2; Each dashed dotted line represents an optional double bond. an ethylenically unsaturated monomer having an unsaturated heterocyclic group having at least one nitrogen atom, the monomer (M2) is different from the monomers (AA) and (AM) and has the following formula (III): 【Chemistry 14】 (In the formula, R ｉ is H, -COOH, -CH ２ COOH or an alkyl group, the alkyl group being preferably a methyl group; R ｉｉ and R ｉｉｉ are the same or different and may be selected from a hydrogen atom or a linear or branched alkyl group having 1 to 6 carbon atoms, or may be a —COOH group; B is a bond selected from the group consisting of a —C(O)—O— group and a —C(O)—NH— group; R ｘ is a hydrogen atom, an ether (—O—), a heterocyclic group, a sulfonic acid group (—SO ３ H), salts of sulfonic acid groups (—SO ３ Cat), phosphonic acid group (-PO ３ H ２ ), a salt of a phosphonic acid group (—PO ３ Cat ２ ), phosphate group (-OPO ３ H ２ ) and salts of phosphate groups (-OPO ３ Cat ２ ) a linear or branched C containing at least one functional group selected from the group consisting of ３ ~C ２０ Cat is preferably a monovalent cation selected from alkali metal cations, more preferably Na ＋ , K. ＋ and Li ＋ (selected from and a repeating unit having a process comprising: - step II) dry-mixing, in the absence of a solvent, at least one electrode active material (AM), a binder (B) as defined above, and optionally at least one conductive agent to obtain a dry electrode-forming composition [composition (C1)]; - step III) feeding the composition (C1) obtained in step ii) into a press to form a self-supporting dry film; and - Step IV) applying the dry film to a conductive substrate to form an electrode; A method for producing an electrode [electrode (E1)] for an electrochemical cell, comprising, or preferably consisting of,

9. 9. The method according to claim 8, wherein the weight ratio of PTFE / polymer (P) in composition (C1) is comprised between 95 / 5 wt / wt and 5 / 95 wt / wt.

10. 10. An electrode (E1) for a secondary battery obtainable by the method according to claim 8 or 9.

11. a) providing a polymer (P), which polymer (P) (A) a repeating unit derived from at least one α,β-ethylenically unsaturated carboxylic acid monomer [monomer (AA)]; (B) Formula (I): 【Chemistry 15】 (In the formula, R ５ represents a hydrogen atom or a methyl group, R ６ and R ７ are the same or different and may be selected from a hydrogen atom or a linear or branched alkyl group having 1 to 6 carbon atoms; R ８ and R ９ may be the same or different and may be selected from the group consisting of a hydrogen atom, a linear or branched alkyl group having 1 to 6 carbon atoms, a carboxyl group, and an amide group. and a repeating unit derived from at least one (meth)acrylamide monomer [monomer (AM)] of the formula: (C) optionally, a repeating unit derived from at least one monomer (M) selected from the group consisting of monomers (M1) and (M2), the monomer (M1) has the following formula (II): 【Chemistry 16】 (In the formula, R １ is H or an alkyl group, the alkyl group being preferably a methyl group; R ２ is H or an alkyl group, R ３ and R ４ are the same or different and may be selected from a hydrogen atom or a linear or branched alkyl group having 1 to 6 carbon atoms; A is, a single covalent bond, and - Spacer is a bond selected from the group consisting of X, Y and Z are independently selected from carbon atoms or nitrogen atoms; a, b and c are independently selected from the integers 1 to 2; Each dashed dotted line represents an optional double bond. an ethylenically unsaturated monomer having an unsaturated heterocyclic group having at least one nitrogen atom, the monomer (M2) is different from the monomers (AA) and (AM) and has the following formula (III): 【Chemistry 17】 (In the formula, R ｉ is H, -COOH, -CH ２ COOH or an alkyl group, the alkyl group being preferably a methyl group; R ｉｉ and R ｉｉｉ are the same or different and may be selected from a hydrogen atom or a linear or branched alkyl group having 1 to 6 carbon atoms, or may be a —COOH group; B is a bond selected from the group consisting of a —C(O)—O— group and a —C(O)—NH— group; R ｘ is a hydrogen atom, an ether (—O—), a heterocyclic group, a sulfonic acid group (—SO ３ H), salts of sulfonic acid groups (-SO ３ Cat), phosphonic acid group (-PO ３ H ２ ), a salt of a phosphonic acid group (—PO ３ Cat ２ ), phosphate group (-OPO ３ H ２ ) and salts of phosphate groups (-OPO ３ Cat ２ ) a linear or branched C containing at least one functional group selected from the group consisting of ３ ~C ２０ Cat is preferably a monovalent cation selected from alkali metal cations, more preferably Na ＋ , K. ＋ and Li ＋ (selected from and a repeating unit having a process comprising: -b) dry-mixing, in the absence of a solvent, at least one electrode active material (AM), the polymer (P) provided in step i) defined above, at least one sulfide-based solid electrolyte or at least one garnet-type inorganic particle-based solid electrolyte, and optionally at least one conductive agent to provide a dry electrode-forming composition [composition (C')]; -c) feeding the composition (C') obtained in step b) into a press to form a self-supporting dry film; and -d) applying the dry film to a conductive substrate to form an electrode. A method for producing an electrode (ESS) for a solid-state battery, comprising, preferably consisting of:

12. An electrode for a secondary battery (ESS) obtainable by the method according to claim 11.

13. 12. The method of any one of claims 1 to 6, 8, 9 or 11, wherein the polymer (P) is in its neutralized form (PN).

14. An electrochemical device such as a secondary battery or a capacitor, wherein at least one of a positive electrode or a negative electrode is the electrode (E) according to claim 7, the electrode (E1) according to claim 10, or the electrode (ESS) according to claim 12.

15. The method of any one of claims 1 to 14, wherein the active material (AM) comprises a material selected from the group consisting of one or more carbon-based materials and one or more silicon-based materials.

16. The active material (AM) has the formula Li(Fe ｘ Mn １－ｘ ) P.O. ４ 16. The method of any one of claims 1 to 15, wherein 0≦x≦1 is a phosphate-based electrode active material, such as lithium iron phosphate (LFP), lithium manganese iron phosphate (LMFP), and lithium manganese phosphate.

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