Anodeless electrochemical cell

Abstract

The invention relates to a battery, to an energy storage or supply system comprising said battery, and to the use of a battery or supply system for storing or supplying electrical power.

Description

Technical Field

[0001] The present invention relates to the field of electrochemical cells, and in particular to anode-less electrochemical cells. Background Art

[0002] Anode-free electrochemical cells are a potential solution to achieve high energy density and address some of the issues with anode-based batteries. In particular, anode-free electrochemical cells exhibit inherent high energy and safety. However, these types of batteries have some drawbacks, such as rapid capacity fade, low Coulombic efficiency (CE), and poor lifespan due to rapid battery cycling degradation.

[0003] Huang et al. (ACS Appl. Mater. Interfaces 2022, 14, 26724-26732) describe an anode-free electrochemical cell comprising a cathode composite material with lithium oxalate as an additive salt. This arrangement demonstrates improvements in battery life cycles and their average coulombic efficiency. However, the use of lithium oxalate in cathode composite materials still has problems that need improvement, such as high cut-off potentials, which make most electrolyte solvents and cathode materials unusable due to their decomposition. In addition, due to the high potential required to oxidize lithium oxalate, the current collector of the battery may have corrosion problems.

[0004] In this sense, there remains a continuing need to develop anode-free electrochemical cells with enhanced overall performance. Summary of the Invention

[0005] The authors of the present invention have developed an anode-free electrochemical cell comprising: an electrode comprising a mixture comprising: an active material and a 3-6 The authors have observed that by using anode-free electrochemical cells comprising a salt of carbonyl anion groups; an electrolyte; a separator; and two current collectors, the performance of the anode-free electrochemical cells is superior to other cells of the prior art. 3-6 The performance of the battery of the present invention is significantly improved by using an electrode containing a salt of a carbon oxyanion group. Furthermore, the authors have observed that, in addition to reduced weight and manufacturing costs, the battery of the present invention without an anode also has better inherent energy density and safety than batteries that include an anode. Furthermore, some batteries with graphite or silicon-based anodes exhibit additional disadvantages such as capacity limitations and volume expansion, which are overcome by the battery of the present invention.

[0006] Thus, a first aspect of the present invention relates to an anode-less electrochemical cell comprising:

[0007] - an electrode (5) comprising a mixture comprising:

[0008] ● Active materials, and

[0009] ●Include C 3-6 Salts of carbonyl anion groups;

[0010] - electrolyte (4);

[0011] - separators; and

[0012] - two current collectors (2, 3);

[0013] Among them, the electrode (5) is a cathode.

[0014] The battery of the invention is configured to act as an energy storage and supply system, ie the battery is configured to be reversibly charged and discharged.Thus, in a second aspect, the invention relates to an energy storage or supply system comprising one or more batteries as defined above.

[0015] Additional aspects of the invention relate to the use of a battery of the invention in any specific embodiment thereof or an energy storage or supply system of the invention in any specific embodiment thereof for storing or supplying energy.

[0016] Another additional aspect relates to a method of making the battery of the present invention.

[0017] Furthermore, additional aspects relate to methods of storing or supplying energy comprising using the battery of the invention in any specific embodiment thereof or the energy storage or supply system of the invention in any specific embodiment thereof. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] These drawings are for illustrative purposes only and are not intended to limit the scope of the present invention.

[0019] Figure 1 An embodiment of a battery (1) is shown comprising current collectors (2, 3), an electrolyte (4) and an electrode mix (5).

[0020] Figure 2 Initial charge / discharge curves for an embodiment of a battery are shown, showing voltage versus specific capacity (mAh / g) for (i) initial charge and (ii) initial discharge.

[0021] Figure 3 The charge capacity at C / 10 and a cutoff potential of 4.3 V is shown for cells having a composite material comprising (i) lithium oxalate or (ii) a lithium squarate salt as the cathode. DETAILED DESCRIPTION

[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the art to which this disclosure belongs. As used herein, singular forms ("a," "an," and "the") include plural references unless the context clearly dictates otherwise.

[0023] In the context of the present invention, the term "carbon oxyanion" refers to a carbon oxyanion consisting of carbon, oxygen and optionally hydrogen atoms. In an embodiment, the salt includes a carbon oxyanion, in particular C 3-6 In a particular embodiment, the salt of the electrode mixture is composed of carbon oxyanions such as C 3-6 The carbonyl group is composed of a carbon oxyanion and at least one counterion; preferably, the counterion is at least a lithium (I) cation.

[0024] In the context of the present invention, the term "C 3-6 "Carbon oxyanion" refers to a carbon oxyanion consisting of carbon, oxygen and optionally hydrogen atoms, having between 3 and 6, preferably between 4 and 6, more preferably 4 or 5 carbon atoms. In a specific embodiment, the carbon oxyanion consists of carbon and oxygen atoms.

[0025] As stated above, in a first aspect, the present invention relates to an anode-less electrochemical cell comprising:

[0026] - an electrode comprising a mixture; wherein the mixture comprises:

[0027] Active materials, and

[0028] Including C 3-6 Salts of carbonyl anion groups;

[0029] - electrolytes;

[0030] - separators; and

[0031] - two current collectors;

[0032] Among them, the electrode (5) is a cathode.

[0033] In an embodiment, the cell of the present invention is an electrochemical cell or battery; preferably an anode-less electrochemical cell or battery; more preferably an anode-less lithium ion cell or battery.

[0034] In the context of the present invention, the term "anode-free" with respect to the battery of the invention means that the battery has no anode, in particular the battery has only one electrode as cathode.

[0035] electrode

[0036] In an embodiment, the electrode of the battery comprises a mixture comprising: (i) an active material; (ii) a binder; (iii) a conductive material; and (iv) a mixture comprising C 3-6 Salts of carbonyl anion groups, preferably including C 3-6 Lithium salts of carbonyl anion groups.

[0037] In another embodiment, the battery electrode is composed of a mixture comprising: (i) an active material; (ii) a binder; (iii) a conductive material; and (iv) a mixture comprising C 3-6 Salts of carbonyl anion groups, preferably including C 3-6 Lithium salts of carbonyl anion groups.

[0038] In yet another embodiment, the battery's electrodes are comprised of a mixture consisting of: (i) an active material; (ii) a binder; (iii) a conductive material; and (iv) a mixture comprising C 3-6 Salts of carbonyl anion groups, preferably including C 3-6 Lithium salts of carbonyl anion groups.

[0039] In an embodiment, the mixture is a composite material; preferably a solid composite material. In an alternative embodiment, the mixture is a composite material that has been cast onto one of the two current collectors of the battery, in particular a composite material that has been cast onto the surface of one of the two current collectors of the battery. In a more specific embodiment, the mixture of electrodes forms a layer on the surface of one of the two current collectors of the battery of the present invention. In the context of the present invention, a "composite material" is understood to be a combination of two or more materials having different physical and chemical properties known in the art.

[0040] The expression "active material" refers to active materials commonly understood in the field of batteries, such as materials that participate in the chemical reactions of the battery.

[0041] In certain embodiments, the active material of the electrode mixture is a cathode active material.

[0042] In an embodiment, the active material comprises a metal element; preferably an alkali metal element; more preferably an alkali metal selected from the group consisting of sodium, potassium, lithium and mixtures thereof; preferably lithium. In a more specific embodiment, the active material is a lithium compound.

[0043] In certain embodiments, the active material is an intercalation material, a conversion material, or a combination thereof.

[0044] In the context of the present invention, the expression "intercalation material" refers to layered materials comprising or inserting molecules or ions as known in the art relating to batteries and electrochemical cells, such as graphite or transition metal dichalcogenides.

[0045] In the context of the present invention, the expression "conversion material" refers to conversion-type electrode materials known from the art of batteries and electrochemical cells.

[0046] In a particular embodiment, the active material comprises a compound selected from the group consisting of: phosphates, oxides, chalcogen-based compounds (e.g., compounds containing S, Se, and / or Te); halogen-based compounds such as fluorine-based compounds, or mixtures thereof; preferably, the active material comprises phosphates, oxides, or mixtures thereof.

[0047] In another specific embodiment, the active material is composed of a compound selected from the group consisting of: phosphates, oxides, chalcogen-based compounds (e.g., compounds containing S, Se and / or Te); halogen-based compounds, such as fluorine-based compounds, or mixtures thereof; preferably, the active material is a phosphate, an oxide, or a mixture thereof.

[0048] Non-limiting examples of phosphates suitable as active materials are lithium-containing phosphates; preferably lithium metal phosphates, such as Li 1-x FeMn x PO4, where 0 < x ≤ 1, or Li3V2(PO4)3; lithium metal fluorophosphates, such as Li2FePO4F, LiV 1-x M x PO4F, where M is Al or Cr, or Li3(VO 1-x PO4)2F 1+2x , wherein 0≤x≤0.5; or a mixture thereof.

[0049] Non-limiting examples of halogen-based compounds suitable as active materials are halogen-based compounds comprising a halogen selected from the group consisting of F, I, Br, and mixtures thereof; preferably, halogen-based compounds including F.

[0050] Non-limiting examples of suitable chalcogen-based compounds are chalcogen-based compounds containing S, Se and / or Te; preferably transition metal dichalcogenides having the formula ME2, wherein M is a transition metal and E is selected from S, Se and Te.

[0051] Non-limiting examples of oxides suitable as active materials are metal oxides, such as vanadium oxide V2O5; preferably metal oxides selected from the group consisting of lithium nickel manganese cobalt oxide (NMC), such as LiNi x Mn 1-x-y Co y O2, wherein x is lower than or equal to 0.9 and y is higher than or equal to 0.05, preferably LiNi x Mn 1-x-y Co yO2, wherein x is less than or equal to 0.6 and y is greater than or equal to 0.20; lithium nickel manganese oxide (LNMO); lithium nickel cobalt aluminum oxide (NCA); lithium manganese oxide (LMO); lithium cobalt oxide (LCO); lithium nickel oxide (LNO), or a mixture thereof.

[0052] In a specific embodiment, the active material is an oxide; preferably a lithium-containing oxide; more preferably a lithium transition metal oxide, such as lithium cobalt oxide (LCO), lithium manganese oxide (LMO), lithium nickel manganese cobalt oxide (NMC) and lithium nickel cobalt aluminum oxide (NCA); even more preferably lithium nickel manganese cobalt oxide (NMC); even more preferably Li 1.00 Ni 0.33 Mn 0.33 Co 0.33 O2.

[0053] In a more specific embodiment, the active material is Li 1+x M 1-y O2, wherein M is selected from Mn, Ni, Co, Al or a mixture thereof, and wherein 0<x≤1 and 0<y≤0.33.

[0054] In a more specific embodiment, comprising C 3-6 The salt of the carbon oxyanion group is an alkali metal C 3-6 Carbon oxide salt or mixture of salts; preferably alkali metal C 3-6 A carbon oxysalt or a mixture of salts, wherein the alkali metal is selected from the group consisting of lithium, sodium, potassium and mixtures thereof.

[0055] In a more specific embodiment, comprising C 3-6 The salt of the carbon oxyanion group is lithium C 3-6 Carbon oxide salts.

[0056] In a specific embodiment, C 3-6 The carbon oxyanion group is a partially hydrided anion or a non-hydrided anion; preferably a non-hydrided anion.

[0057] In a specific embodiment, C 3-6The carbon oxyanion group is selected from the group consisting of delta acid salt, mesooxalate, acetylene dicarboxylate, squarate, dioxosuccinate, croconate, methane tetracarboxylate, rhodoxalate, benzoquinone tetraoleate, phenylhexanoate, ethylene tetracarboxylate and mixtures thereof; preferably selected from the group consisting of acetylene dicarboxylate, squarate, dioxosuccinate, croconate, methane tetracarboxylate, rhodoxalate, benzoquinone tetraoleate, phenylhexanoate, ethylene tetracarboxylate and mixtures thereof; more preferably selected from the group consisting of acetylene dicarboxylate, squarate, dioxosuccinate, croconate, methane tetracarboxylate and mixtures thereof; even more preferably selected from the group consisting of acetylene dicarboxylate, squarate, dioxosuccinate and mixtures thereof; even further more preferably selected from the group consisting of acetylene dicarboxylate, squarate, dioxosuccinate and mixtures thereof; and even more preferably squarate.

[0058] In a more specific embodiment, comprising C 3-6 The salt of the carbon oxyanion group is lithium squarate (Li2C4O4).

[0059] In an embodiment, the electrode mixture further comprises a conductive material.

[0060] In a specific embodiment, the conductive material in the mixture is a conductive carbonaceous material; preferably conductive carbon black, more preferably C65 carbon black.

[0061] In the context of the present invention, the expression "carbon black" refers to the meaning commonly understood in the art, ie carbon black in the form of quasi-crystalline carbon having a high surface area to volume ratio, but lower than that of activated carbon.

[0062] In an embodiment, the mixture further comprises a binder. In a specific embodiment, the binder of the mixture is a thermoplastic polymer, copolymer, or mixture thereof; more preferably, a thermoplastic polymer, copolymer, or mixture thereof containing a halogen group; preferably, a thermoplastic polymer, copolymer, or mixture thereof containing fluorine; more preferably, a vinyl polymer containing fluorine; and even more preferably, poly(vinylidene fluoride) (PVDF).

[0063] In an embodiment, the mass ratio of the active material to the salt in the mixture is between 100:0.2 and 100:90 (inclusive); preferably, the mass ratio is between 100:0.5 and 100:85 (inclusive); more preferably, the mass ratio is between 100:1 and 100:70 (inclusive); even more preferably, the mass ratio is between 100:18 and 100:30 (inclusive), and more preferably about 100:20.

[0064] In another embodiment, the mass ratio of active material to binder is between 100:0.1 and 100:50 (inclusive); preferably between 100:05 and 100:30 (inclusive); more preferably between 100:03 and 100:15.

[0065] In an embodiment, the mass ratio of the active material, the conductive carbonaceous material, and the binder is between 60:30:10 and 92:5:3 (inclusive).

[0066] In a particular embodiment, the mixture is composed of an active material, a binder, a conductive carbonaceous material and a 3-6 The salt composition of carbon oxyanion group, preferably, wherein C 3-6 The carbon oxyanion group is C 3-6 Lithium carbonyl salt.

[0067] In a particular embodiment, the mixture consists of an active material comprising lithium, a binder, a conductive carbonaceous material, and lithium squarate.

[0068] current collector

[0069] In a specific embodiment, the current collector is a metallic current collector; preferably a current collector made of metal or an alloy; preferably made of aluminum, copper, nickel, stainless steel or a mixture thereof; more preferably made of aluminum and / or copper.

[0070] In a particular embodiment, the battery includes two current collectors:

[0071] - wherein a surface of at least one of the side surfaces of a current collector is in contact with a mixture of electrodes of a battery, and

[0072] - wherein all surfaces of at least one of the side surfaces of the other current collector are in contact with the electrolyte.

[0073] In a specific embodiment, the surface of at least one side of a current collector is in contact with the mixture of the battery electrodes; preferably, the surface of at least one side of a current collector is coated with the mixture of the battery electrodes; more preferably, the surface of at least one side of a current collector is coated with a layer of the mixture of the battery electrodes; even more preferably, all surfaces of at least one side of a current collector are coated with a layer of the mixture of the battery electrodes; in particular, it is in direct physical contact.

[0074] In certain embodiments, all surfaces of at least one side of a current collector are in contact with the electrolyte; in particular, in direct physical contact with the electrolyte.

[0075] In a more particular embodiment, the battery comprises two current collectors; wherein one current collector is in contact with the mixture of the battery, and wherein the other current collector is in contact with the electrolyte; and preferably, wherein the current collector in contact with the mixture is made of aluminum and the current collector in contact with the electrolyte is made of copper.

[0076] electrolytes

[0077] In an embodiment, the electrolyte includes an active material. The term "active material" refers to an electroactive material that can undergo an electrochemical reaction at an electrode of a battery as known in the art.

[0078] In certain embodiments, the electrolyte includes an alkali metal compound and a solvent or solvent mixture.

[0079] In another specific embodiment, the electrolyte consists of an alkali metal compound and a solvent or a solvent mixture; preferably, the electrolyte consists of a lithium compound and a solvent or a solvent mixture; more preferably, the electrolyte consists of a lithium salt and a solvent or a solvent mixture.

[0080] In a specific embodiment, the electrolyte comprises an alkali metal compound; preferably a lithium compound; preferably a lithium compound selected from the group consisting of lithium salts, lithium conductive polymers, and mixtures thereof.

[0081] Non-limiting examples of lithium compounds suitable for use as electrolytes are LiPF6, LiBF4, LiBF6, LiAsF6, LiClO4, LiSbF6, LiCF3SO3Li, LiC4F9SO3, LiAlF4, LiAlCl4, LiCl, LiI, lithium sulfonimides such as LiN(C x F 2x+1 SO2)(C y F 2+y SO2), wherein x and y are natural numbers satisfying 0≤x≤4 and 0≤y≤4, such as lithium bis(fluorosulfonyl)imide (LiFSI) or lithium bis(trifluoromethane)sulfonylimide (LiTFSI), lithium poly(styrenesulfonyl-trifluoromethanesulfonylimide) (LiPSTFSI), lithium poly(acrylamidopropylsulfonyl-trifluoromethanesulfonylimide) (LiMAPTFSI), lithium poly(methacrylamidopropylsulfonyl-trifluoromethanesulfonylimide) (LiMMPTFSI), lithium 4,5-dicyano-2-(trifluoromethyl)imidazole (LiTDI), and mixtures thereof.

[0082] In a more specific embodiment, the electrolyte includes lithium hexafluorophosphate (LiPF6).

[0083] In a specific embodiment, the electrolyte comprises an organic solvent selected from compounds comprising carbonate groups, ester groups, ether groups, ketone groups, alcohol groups, or combinations thereof; preferably, compounds comprising carbonate groups, ether groups, or combinations thereof.

[0084] In an embodiment, the carbonate group-containing compound suitable for use as a solvent is a linear or cyclic carbonate.

[0085] In an embodiment, the compound containing a carbonate group suitable for use as a solvent is selected from alkyl carbonates, such as dimethyl carbonate (DMC), diethyl carbonate (DEC), dipropyl carbonate (DPC), ethyl methyl carbonate (EMC), methyl propyl carbonate (MPC), ethyl propyl carbonate (EPC) or mixtures thereof; alkylene carbonates such as ethylene carbonate (EC); fluorinated carbonates such as fluorinated cyclic carbonates (F-AEC) or fluorinated linear carbonates (F-EMC) and mixtures thereof.

[0086] In certain embodiments, compounds suitable for use as solvents are fluorinated organic compounds, preferably fluorinated ethers, such as fluorinated ethers (F-EPEs), hydrofluoroethers, and mixtures thereof. In certain embodiments, the electrolyte comprises a mixture of ethylene carbonate (EC) and dimethyl carbonate (DMC); even more preferably, a mixture of ethylene carbonate (EC) and dimethyl carbonate (DMC) in a mass ratio of between 1:0.5 and 1:2; preferably between 1:0.8 and 1:1.5; more preferably about 1:1.

[0087] In a specific embodiment, the electrolyte comprises a mixture of a lithium salt and a carbonate; more preferably, a mixture of lithium hexafluorophosphate (LiPF6) with ethylene carbonate (EC) and dimethyl carbonate (DMC); more preferably, wherein the mass ratio of ethylene carbonate (EC) to dimethyl carbonate (DMC) is between 1:0.5 and 1:2; preferably between 1:0.8 and 1:1.5; more preferably about 1:1.

[0088] In a specific embodiment, the electrolyte consists of a mixture of a lithium salt and a carbonate; more preferably, lithium hexafluorophosphate (LiPF6) and a mixture of ethylene carbonate (EC) and dimethyl carbonate (DMC); more preferably, wherein the mass ratio of ethylene carbonate (EC) to dimethyl carbonate (DMC) is between 1:0.5 and 1:2; preferably between 1:0.8 and 1:1.5; more preferably about 1:1.

[0089] In certain embodiments, the electrolyte is a liquid electrolyte.

[0090] separators

[0091] Any separator known in the art associated with anode-free electrochemical cells can be used in the present invention. In certain embodiments, the separator is made of an electrically insulating material. Non-limiting materials suitable for the separator include insulating polymers with or without ceramic coatings, such as polycarbonate or polypropylene, cellulose-based materials such as paper, fiberglass, and the like.

[0092] In an embodiment, the separator is between the electrolyte and the mixture of the battery; preferably is in contact with the electrolyte and the mixture; more preferably, wherein the separator comprises two sides, and wherein one side is in contact with the electrolyte and the other side is in contact with the mixture.

[0093] In an embodiment, the separator is a membrane, preferably a fiberglass or polypropylene membrane.

[0094] In an embodiment, the anode-free electrochemical cell (1) of the present invention consists of:

[0095] - an electrode (5) comprising a mixture comprising:

[0096] Active materials, and

[0097] ●Include C 3-6 Salts of carbonyl anion groups;

[0098] - electrolyte (4);

[0099] - separators; and

[0100] - two current collectors (2, 3);

[0101] Among them, the electrode (5) is a cathode.

[0102] One aspect of the present invention relates to a method of making a battery according to any specific embodiment of the present invention, the method comprising an electrode preparation step, the electrode preparation step comprising:

[0103] (i) Provide at least the following materials:

[0104] a. Active materials,

[0105] b. Include C 3-6 Salts of carbonyl anion groups; and

[0106] c. solvent;

[0107] (ii) mixing the materials of step (i) to form a mixture;

[0108] (iii) casting the mixture onto a current collector; and

[0109] (iv) Drying the mixture to form an electrode.

[0110] Electrode preparation

[0111] In certain embodiments, the electrode preparation step comprises:

[0112] (i) Provide at least the following materials:

[0113] a. Active materials,

[0114] b. Include C 3-6 Salt of carbon oxyanion; preferably C 3-6 lithium oxycarbon salts; and

[0115] c. solvent;

[0116] (ii) mixing the materials of step (i) to form a mixture;

[0117] (iii) casting the mixture of step (ii) on a current collector; and

[0118] (iv) drying the mixture.

[0119] In a specific embodiment, the active material of step (i) is any active material described above in any of the specific embodiments with respect to the battery.

[0120] In an embodiment, the electrode of the electrode preparation step of the method of making a battery is the cathode of the battery.

[0121] In a specific embodiment, the mixture of step (i) and step (ii) further comprises a binder; preferably, the binder is any binder described above in any specific embodiment with respect to the battery.

[0122] In a specific embodiment, the mixture of step (i) and step (ii) further comprises a conductive material; preferably, the conductive material is any conductive material described above in any specific embodiment with respect to the battery.

[0123] In certain embodiments, the salt has a C 3-6 The carbon oxyanion group is a partially hydrided anion or a non-hydrided anion; preferably a non-hydrided anion.

[0124] In certain embodiments, the salt has a C 3-6The carbon oxyanion group is selected from the group consisting of delta acid salt, meta-oxalate, acetylene dicarboxylate, squarate, dioxosuccinate, croconate, methane tetracarboxylate, rhodonate, benzoquinone tetraoleate, phenylhexanoate, ethylene tetracarboxylate and mixtures thereof; preferably selected from the group consisting of acetylene dicarboxylate, squarate, dioxosuccinate, croconate, methane tetracarboxylate, rhodonate, benzoquinone tetraoleate, phenylhexanoate, ethylene tetracarboxylate and mixtures thereof; more preferably selected from the group consisting of acetylene dicarboxylate, squarate, dioxosuccinate, croconate, methane tetracarboxylate and mixtures thereof; even more preferably selected from the group consisting of acetylene dicarboxylate, squarate, dioxosuccinate and mixtures thereof; even further more preferably selected from the group consisting of acetylene dicarboxylate, squarate, dioxosuccinate and mixtures thereof;

[0125] In a more specific embodiment, comprising C 3-6 The salt of the carbon oxyanion group is lithium C 3-6 Carbon oxysalt; preferably lithium squarate (Li2C4O4).

[0126] In a specific embodiment, the solvent of step (i) is an organic solvent; more preferably, an organic compound comprising an amide; even more preferably, an organic compound comprising a cyclic amide; further more preferably, a pyrrolidone, such as N-methyl-2-pyrrolidone (NMP).

[0127] In an embodiment, the mass ratio of active material to salt is between 100:0.2 and 100:90 (inclusive); preferably, the mass ratio is between 100:0.5 and 100:85 (inclusive); more preferably, the mass ratio is between 100:1 and 100:70 (inclusive); even more preferably, the mass ratio is between 100:18 and 100:30 (inclusive), more preferably about 100:20.

[0128] In certain embodiments, the mixture is cast by a doctor blade or tape casting method.

[0129] In a particular embodiment, the mixture is cast in step (iii) to obtain a wet thickness of between 50 and 400 microns, preferably between 100 and 300 microns; more preferably between 150 and 250 microns; even further more preferably about 200 microns.

[0130] In a particular embodiment, the current collector of step (iii) is one of the two current collectors of the battery.

[0131] In a particular embodiment, the current collector of step (iii) is a film; preferably a metal foil; more preferably an aluminum foil.

[0132] In a particular embodiment, step (iv) comprises drying the mixture at between 50°C and 150°C; preferably drying the mixture at between 60°C and 120°C; more preferably drying the mixture at between 70°C and 100°C; even more preferably drying the mixture at about 80°C.

[0133] In a particular embodiment, step (iv) comprises drying the mixture over a period of between 1 minute and 24 hours; preferably drying the mixture over a period of between 10 minutes and 20 hours; more preferably drying the mixture over a period of between 30 minutes and 15 hours; more preferably drying the mixture over a period of about 12 hours.

[0134] In a particular embodiment, step (iv) comprises drying the mixture in an oven; preferably drying the mixture in a vacuum oven.

[0135] In a particular embodiment, the method further comprises a step (v) in which the dried mixture obtained from step (iv) is subjected to compression to reduce its thickness. Said process can be carried out by hot and / or cold densification or by calendering and is well known to the skilled person.

[0136] For example, densification can be performed by hot pressing, during which controlled pressure and temperature are simultaneously applied to mold the product.

[0137] Alternatively, the dried mixture can be calendered, which means smoothing and compressing the mixture by passing it through several pairs of heated rollers.

[0138] The temperature in both processes is preferably between 25 and 150°C, more preferably between 60 and 150°C, even more preferably between 80 and 130°C.

[0139] In certain embodiments, the thickness of the dried mixture is reduced by 5% to 50% relative to the wet thickness of the same mixture.

[0140] In an embodiment, the method of manufacturing a battery of the present invention further comprises:

[0141] (v) providing the following elements: a separator, an additional current collector, and an electrolyte, and

[0142] (vi) assembling all the components of step (v) with the electrodes of step (iv) to form a battery;

[0143] wherein only the current collector of step (iii) is in contact with the electrode mixture, and

[0144] Preferably, a separator is placed between the electrolyte and the electrodes.

[0145] The authors of the present invention have observed that the use of electrodes comprising the mixture described above in the batteries of the invention leads to high charge capacity values.

[0146] Energy storage or supply systems

[0147] In a second aspect, the invention relates to an energy storage or supply system comprising one or more batteries as defined above in any specific embodiment thereof.

[0148] use

[0149] An additional aspect of the invention relates to the use of a battery as defined above in any specific embodiment of the invention or an energy storage or supply system as defined above for storing or supplying energy, in particular in the field of renewable energy and electric vehicles.

[0150] One aspect of the invention relates to a method for storing energy or supplying energy comprising the use of a battery as defined in any specific embodiment of the invention.

[0151] To this end, the batteries of the present invention may be used alone or in combination with other energy storage technologies, and may be integrated into or with various systems and / or devices to improve efficiency, address energy needs, and the like.

[0152] Furthermore, the batteries of the present invention can be used in a variety of applications with different energy supply and / or storage requirements, including but not limited to very large-scale applications (e.g., facilities serving as green energy for smart grids, energy storage used in combination with renewable energy sources such as wind and solar power, etc.) and smaller applications (e.g., backup power, residential power, the electric vehicle industry, etc.).

[0153] Throughout the specification and claims, the word "comprise" and variations of the word are not intended to exclude other technical features, additives, components, or steps. In addition, the word "comprising" encompasses "consisting of." Additional objects, advantages, and features of the present invention will become apparent to those skilled in the art upon examination of the specification or may be learned through practice of the present invention.

[0154] The present invention will be described in more detail with reference to the following examples. These examples are for illustrative purposes only and are not intended to limit the scope of the present invention.

[0155] Example

[0156] Example 1 - Battery Cell Preparation

[0157] An anode-free lithium metal battery (AFLMB) cell was prepared using a cathode composite material comprising Li 1.00 Ni 0.33Mn 0.33 Co 0.33 O2 (NMC 111) as the active material and lithium squarate (Li2C4O4) salt on Al foil (the Al foil serves as the cathode current collector); 1M LiPF6 in ethylene carbonate (EC) and dimethyl carbonate (DMC) (EC:DMC mass ratio is 50:50) as the electrolyte; glass fiber as the separator; Cu foil and the Al foil as the current collector.

[0158] The cathode composite material was prepared by mixing (a) active material (NMC 111), super carbon C65 and poly (vinylidene fluoride) (PVDF) in a mass ratio of 80:10:10 with (b) lithium squarate (Li2C4O4) salt / C65 (70 / 30 wt%) in N-methyl-2-pyrrolidone (NMP) to prepare a slurry. The mixture was kept under vigorous stirring for 1 hour using a mechanical stirrer device. The slurry was then cast onto an aluminum current collector foil using a doctor blade instrument, controlling the wet thickness to 200 microns, and then dried in a vacuum oven at 80°C for 12 hours. The electrode was not pressed before being assembled into the battery. The cathode composite components of the battery of this example include Li as the active material 1.00 Ni 0.33 Mn 0.33 Co 0.33 O2 (NMC 111) and lithium squarate (Li2C4O4) salt, the mass ratio of the two is about 100:20.

[0159] Figure 1 A specific embodiment of a battery cell (1) is shown, which includes a Cu current collector (2), a second current collector (3), an EC / DMC / LiPF6 electrolyte (4), and a positive electrode (5) including an active material and a salt complex.

[0160] Example 2 - Battery Unit Test

[0161] Figure 2 Initial charge / discharge curves for the battery cell of Example 1 are shown, which show the results of voltage (V) versus specific capacity (mAh / g) for (i) initial charge and (ii) initial discharge. Figure 2 The excess capacity due to the use of a lithium squarate as a cathode additive is shown in (iii). In particular, the results show that the lithium squarate (Li2C4O4) is oxidized during the initial charge, resulting in an increase in the additional capacity. This allows the Li+ ions to be reversely intercalated back into the cathode, and the capacity is 140 mAh / g, as shown in Figure 2 As can be observed in .

[0162] Furthermore, the results show that the cathode composition results in a cutoff potential of 4.3 V, which falls within the conventional charging potential of NMC cathodes, thereby preventing electrolyte aging and cathode material decomposition, and improving the overall battery life and cycling performance of the system, especially in the case of high fast charging.

[0163] Example 3 - Comparative Test

[0164] Comparative testing was performed using a cell similar to the cell described in Example 1 but including a squarate or lithium oxalate salt as a salt additive in the cathode composite.

[0165] Figure 3 The charge capacity of cells including (i) lithium oxalate or (ii) squarate additive mixed with Super Carbon C65 is shown within a cutoff potential of 4.3 V at C / 10. Figure 3 The charge capacity (added lithium) of the lithium oxalate salt is shown to be only 8 mAh / g, whereas a charge capacity of 268 mAh / g is obtained for the squarate salt.

Claims

1. An anode-free electrochemical cell (1), comprising: - an electrode (5), said electrode (5) comprising a mixture comprising: Active materials, and ●Include C 3-6 Salts of carbonyl anion groups; - electrolyte (4); - separators; and - two current collectors (2, 3); Wherein, the electrode (5) is a cathode.

2. The battery according to claim 1, wherein The carbon oxyanion group is selected from the group consisting of delta acid salt, mesooxalate, acetylene dicarboxylate, squarate, dioxosuccinate, croconate, methane tetracarboxylate, rosette salt, benzoquinone tetraoleate, phenylhexanoate, ethylene tetracarboxylate, and mixtures thereof.

3. The battery according to any one of claims 1 or 2, wherein The carbon oxyanion group is selected from the group consisting of acetylene dicarboxylates, squarates, and dioxosuccinates.

4. The battery according to any one of claims 1 to 3, wherein The salt is a lithium salt.

5. The battery according to claim 4, wherein The salt is lithium squarate.

6. The battery according to any one of claims 1 to 5, wherein The active material is selected from lithium nickel manganese cobalt oxide (NMC), lithium nickel manganese oxide (LNMO), lithium nickel cobalt aluminum oxide (NCA), lithium manganese oxide (LMO), lithium cobalt oxide (LCO), or a mixture thereof.

7. The battery according to claim 6, wherein The active material is lithium nickel cobalt manganese oxide (NMC).

8. The battery according to any one of claims 1 to 7, wherein The mass ratio of active material to salt in the mixture is between 100:0.2 and 100:90, inclusive.

9. The battery according to any one of claims 1 to 8, wherein The mixture consists of an active material containing lithium, lithium squarate, a conductive material, and a binder.

10. The battery according to any one of claims 1 to 9, wherein The electrolyte includes: - a lithium compound selected from the group consisting of lithium salts, lithium conductive polymers and mixtures thereof; and - a compound comprising a carbonate group selected from the group consisting of alkyl carbonates, alkylene carbonates, fluorinated carbonates and mixtures thereof.

11. The battery according to claim 10, wherein The electrolyte includes: a mixture of lithium hexafluorophosphate (LiPF6), ethylene carbonate (EC) and dimethyl carbonate (DMC); wherein the mass ratio of the ethylene carbonate (EC) to the dimethyl carbonate (DMC) is between 1:0.5 and 1:

2.

12. The battery according to any one of claims 1 to 11, wherein All surfaces of at least one of the side surfaces of one of the two current collectors are in contact with the electrolyte, and wherein the other of the two current collectors is in contact with a mixture of electrodes of the battery.

13. The battery according to any one of claims 1 to 12, wherein The electrolyte comprises: a mixture of lithium hexafluorophosphate (LiPF6) and ethylene carbonate (EC) and dimethyl carbonate (DMC); wherein the mass ratio of the ethylene carbonate (EC) to the dimethyl carbonate (DMC) is between 1:0.5 and 1:2; and wherein the active material is selected from lithium nickel manganese cobalt oxide (NMC), lithium nickel manganese oxide (LNMO), lithium nickel cobalt aluminum oxide (NCA), lithium manganese oxide (LMO), lithium cobalt oxide (LCO) or a mixture thereof.

14. The battery according to any one of claims 1 to 13, wherein The mass ratio of active material to salt in the mixture is between 100:18 and 100:30, inclusive.

15. The battery according to any one of claims 1 to 14, wherein The battery (1) is composed of the following: - an electrode (5), said electrode (5) comprising a mixture comprising: Active materials, and ●Include C 3-6 Salts of carbonyl anion groups; - electrolyte (4); - separators; and - two current collectors (2, 3); Wherein, the electrode (5) is a cathode.

16. A method for manufacturing a battery according to any one of claims 1 to 15, the method comprising an electrode preparation step, the electrode preparation step comprising: (i) Provide at least the following materials: a. Active materials, b. Include C 3-6 Salts of carbonyl anion groups; and c. solvent; (ii) mixing the materials of step (i) to form a mixture; (iii) casting the mixture onto a current collector; as well as (iv) drying the mixture to form an electrode.

17. An energy storage or supply system comprising one or more batteries according to any one of claims 1 to 15.

18. Use of a battery according to any one of claims 1 to 15 or an energy storage or supply system according to claim 17 for storing or supplying electricity.

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