Battery cell

Abstract

To provide a battery cell.SOLUTION: The present invention relates to battery cells comprising a cathode current collector, a cathode, an anode current collector, optionally an anode, and a solid state electrolyte comprising a non-aqueous solvent, an aluminum-based halogenated compound AlXn and / or a polymeric form thereof, a metal salt of the alkali metal, the alkaline earth metal or the metal of Group Ib, Group IIb, or Group IIIa of the periodic table, and a bis (fluorosulfonyl) imide (FSI) anion, where X is a halogen atom and n is between 1 and 6.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to battery cells and batteries including solid electrolytes. [Background technology]

[0002] Recently, the development and improvement of batteries for various devices requiring batteries, such as mobile phones, wireless household appliances, and electric cars and motorcycles, has become an important area of ​​research and interest. In particular, the field of secondary batteries continues to advance with the development of smaller, thinner batteries with improved life spans.

[0003] In response to these recent developments, lithium secondary batteries, which have lithium metal as the active material, have attracted attention. Lithium metal is known to have a low redox potential (-3.045 V vs. the standard hydrogen electrode) and a high gravimetric energy density (3860 mAh / g), making it an attractive material for the cathode (negative electrode).

[0004] It is known to use lithium metal as the cathode by adhering lithium foil to the negative electrode current collector. However, since lithium is an alkali metal, it reacts with water and oxygen due to its high reactivity. This has the drawback that such batteries are considered dangerous, for example, due to the risk of explosion in the event of leakage into the environment. Handling lithium foil is also dangerous.

[0005] Additionally, when lithium metal is exposed to air, oxidation typically results in the formation of an oxide layer, which acts as an insulator, thereby increasing electrical resistance and therefore reducing battery performance.

[0006] To solve this problem, anode-free battery cells have been developed. These cells typically contain only a negative current collector, and a layer of lithium is formed in situ on the negative current collector during the first charge of the battery.

[0007] U.S. Patent Application Publication No. 2016 / 0261000 (Patent Document 1) discloses an anode-free rechargeable battery including a negative electrode current collector, a separator, and a positive electrode. The battery further includes a liquid electrolyte including a salt or salt mixture containing an active metal cation (e.g., lithium ion) dissolved in a non-aqueous solvent, solvent mixture, or polymer. The separator can be injected with the electrolyte. During charging of the battery, a negative electrode is formed in situ on the surface of the negative electrode current collector.

[0008] A drawback of the above electrolytes is that they are liquids, which can lead to leakage of the electrolyte from the battery, resulting in loss of functionality. Another drawback is that the metal (e.g., lithium) ions interact with the solvent, thereby reducing the amount of ions available for in situ deposition as the negative electrode layer and for charging and discharging the battery.

[0009] U.S. Patent Application Publication No. 2020 / 0203757 (Patent Document 2) discloses a lithium secondary battery including an anode, a cathode current collector, a separator, and an electrolyte interposed between the electrodes. The electrolyte is a gel polymer electrolyte that can be crosslinked. The gel polymer electrolyte includes a polymer matrix and a lithium salt dissolved in an organic solvent mixture. A lithium metal layer is formed in situ on the cathode current collector during charging.

[0010] A drawback of gel polymer electrolytes is that their lithium ion conductivity is known to be low, typically less than 1 mS / cm. [Prior art documents] [Patent documents]

[0011] [Patent Document 1] US Patent Application Publication No. 2016 / 0261000 [Patent Document 2] U.S. Patent Application Publication No. 2020 / 0203757 Summary of the Invention

[0012] It is an object of the present invention to overcome one or more of the above-mentioned drawbacks, and to provide a battery cell having improved functionality compared to state-of-the-art battery cells.

[0013] It is an objective to provide a battery cell that can withstand multiple charge / discharge cycles and exhibits good conductivity.

[0014] In a first aspect of the present invention, there is provided a battery cell as set out in the accompanying claims.

[0015] The battery cell includes a positive current collector, a positive electrode, a solid electrolyte, and a negative current collector or electronic conductor.

[0016] The positive electrode current collector can be any positive electrode current collector known in the art, for example, the positive electrode current collector comprises or consists essentially of aluminum.

[0017] Advantageously, the positive electrode comprises an active material, which advantageously comprises or consists essentially of one or more alkali metals, alkaline earth metals or elements from Group Ib, IIb or IIIa of the periodic table.

[0018] Advantageously, the positive electrode further comprises an electronically conductive compound, which may be any electronically conductive compound known in the art.

[0019] Advantageously, the positive electrode further comprises a binder, which may be any binder known in the art.

[0020] Advantageously, the solid electrolyte is a non-aqueous solvent, an aluminum-based halide compound AlX n and / or polymeric forms thereof, metal salts, and bis(fluorosulfonyl)imide (FSI) anions.

[0021] Preferably, the metal salt is an alkali metal, alkaline earth metal, or metal salt of Group Ib, IIb, or IIIa of the periodic table. Preferably, the metal of the metal salt is lithium, sodium, magnesium, aluminum, zinc, or silver. In other words, the metal salt is preferably a lithium salt, sodium salt, magnesium salt, aluminum salt, zinc salt, or silver salt.

[0022] The metal of the metal salt may be the same as or different from the metal contained in the positive electrode. When the solid electrolyte (SSE) contains two or more metal salts, these metals may be the same as or different from the metal contained in the positive electrode. For example, but not limited to, the SSE may contain a combination of two lithium salts or a lithium salt and a magnesium salt.

[0023] Advantageously, as is well known, metal salts contain an anion. As is well known, metal salts also advantageously contain a cation. Advantageously, the cation is the cation of the metal of the metal salt. For example, if the metal salt is a lithium salt, the cation is the lithium cation (Li + )

[0024] The solid electrolyte is an aluminum-based halide compound, AlX n and / or polymeric versions thereof, wherein X is a halogen atom. Advantageously, n is 1 to 6, for example 1 to 3. Advantageously, X is chloride, bromide, or iodide, preferably chloride. Advantageously, AlX n The polymer type of (AlX n ) m where m is 2 or greater.

[0025] Advantageously, X is chloride, n is 3, and the aluminum-based halide compound is AlCl. Advantageously, X is chloride, n is 3, m is 2 or more, and the polymeric aluminum-based halide compound is (AlCl). m is.

[0026] The solid electrolyte further comprises a bis(fluorosulfonyl)imide (FSI) anion. The inventors have surprisingly found that the presence of the FSI anion in the SSE is related to the presence of an aluminum-based halide compound, AlX n and / or have found that the solid-state properties of electrolytes containing these polymeric forms can be maintained.

[0027] Advantageously, in the first embodiment of the solid electrolyte of the battery cell of the present disclosure, the anion of the metal salt is FSI, for example, the metal of the metal salt is lithium (Li), and the metal salt is advantageously LiFSI.

[0028] When the SSE of the first embodiment includes at least one additional metal salt, the anion of the at least one additional metal salt is preferably FSI, bis(trifluoromethane)sulfonimide (TFSI), dicyanamide (DCA), perchloric acid (ClO), sodium tetrachloroaluminate (AlCl), difluorobis(oxalato)borate (DFOB), or hexafluorophosphate (PF). Further examples include, but are not limited to, difluorobis(oxalato)phosphate (DFBOP), tetrafluoroborate (BF), hexafluoroarsenic (AsF), sodium tetrachloroaluminate (AlCl), trifluoromethanesulfonate (CFSO), and (fluoromethylsulfonyl)(trifluoromethylsulfonyl)imide (FTFSI). For example, the SSE may include two metal salts having different cations and both having FSI as the anion, such as LiFSI and NaFSI.

[0029] Advantageously, when at least one anion of the metal salt or two or more metal salts is FSI, the non-aqueous solvent is selected from the group consisting of nitriles, ethers, esters, carbonates, sulfones, amides, and ionic liquids. Non-limiting examples of preferred non-aqueous solvents include acetonitrile, dimethoxyethane, and ionic liquids. Further examples include propylene carbonate, ethylene carbonate, tetrahydrofuran, diethyl carbonate, γ-butyrolactone, 2-methyltetrahydrofuran, 1-3 dioxolane, tetramethylsulfone (sulfolane), and dimethylsulfone (DMSO).

[0030] Ionic liquids are known in the art as salts that are in liquid form at moderate temperatures without the need for the salt to be dissolved in another solvent. Ionic liquids are typically composed of ions—cations and anions. Advantageously, when the non-aqueous solvent is an ionic liquid, it contains an organic cation and an inorganic or organic anion.

[0031] Advantageously, in the second embodiment of the solid electrolyte of the battery cell of the present disclosure, the non-aqueous solvent is an ionic liquid, the anion of which is FSI.

[0032] When the SSE according to the second embodiment comprises at least one additional non-aqueous solvent, the at least one additional non-aqueous solvent is advantageously selected from the group consisting of nitriles, ethers, esters, carbonates, sulfones, amides, and ionic liquids. Preferred examples of the at least one additional non-aqueous solvent include acetonitrile, dimethoxyethane, and ionic liquids. Further examples include propylene carbonate, ethylene carbonate, tetrahydrofuran, diethyl carbonate, γ-butyrolactone, 2-methyltetrahydrofuran, 1-3 dioxolane, tetramethyl sulfone, and dimethyl sulfone.

[0033] When one of the second or further non-aqueous solvents is an ionic liquid, the anion thereof is preferably TFSI, DCA, ClO4, PF6, DFBOP, DFOB, BF4, FTFSI, AlCl4, AsF6, or CF3SO3. For example, an SSE may include two ionic liquids as non-aqueous solvents, each having FSI as the anion and a different cation. Alternatively, each ionic liquid may have different anions, one of which is FSI, and the same cation.

[0034] Advantageously, when the non-aqueous solvent or at least one of the two or more non-aqueous solvents is an ionic liquid having an FSI anion, the anions of the metal salts of the SSE are TFSI, DCA, ClO4, PF6, DFBOP, DFOB, BF4, FTFSI, AlCl4, AsF6 and CF3SO3.

[0035] A third embodiment of the solid electrolyte for a battery cell of the present disclosure includes a combination of the first and second embodiments. In other words, in the third embodiment, the anion of at least one of the metal salt or two or more metal salts is FSI, and the non-aqueous solvent or at least one of the two or more non-aqueous solvents is an ionic liquid, and the anion thereof is FSI.

[0036] Advantageously, the battery cell further comprises a separator, for example, a separator membrane disposed between the positive and negative electrode current collectors. The separator may be any separator known in the art.

[0037] Advantageously, if desired, the battery cell further comprises a negative electrode, i.e., the battery cell is a negative electrode-containing battery cell. The negative electrode may be any negative electrode known in the art.

[0038] Advantageously, the negative electrode comprises or consists essentially of a metal layer comprising an alkali metal, an alkaline earth metal, or a metal from Group Ib, IIb, or IIIa of the periodic table, or a combination of two or more thereof. Preferred examples of metals include lithium, sodium, magnesium, aluminum, zinc, and silver.

[0039] Alternatively, and more preferably, the negative electrode comprises or consists essentially of an intercalation electrode, which may be any electrode known in the art as being suitable for use as a negative electrode.

[0040] Alternatively, and more advantageously, the negative electrode comprises or consists essentially of a conversion electrode, which comprises an oxide, a nitride, a sulfide, or a combination of two or more thereof.

[0041] Optionally, the battery cell may further comprise a high surface area substrate disposed between the positive electrode, or separator, if present, and the negative electrode current collector or electronic conductor, or negative electrode, if present. Advantageously, the high surface area substrate is disposed such that at least a portion of the high surface area substrate is in contact with the surface of the negative electrode current collector or electronic conductor, if present, or the surface of the negative electrode, if present.

[0042] When a battery cell includes a high surface area substrate and does not include a negative electrode, the battery cell that includes the high surface area substrate advantageously includes an electronic conductor.

[0043] When the battery cell includes an electron conductor, it may further include a negative electrode lead extension. Advantageously, when the battery cell includes a negative electrode lead extension, at least a portion of the surface of the electron conductor is in contact with at least a portion of the surface of the negative electrode lead extension.

[0044] Advantageously, the electronic conductor, when present, comprises or consists essentially of a metal, a polymer, carbon, an oxide, a sulfide, a nitride, a carbide, a silicide, or a combination of two or more thereof.

[0045] Advantageously, the battery cell according to the present disclosure is a secondary battery.

[0046] In a second aspect of the present invention, there is provided a battery as set out in the accompanying claims, the battery comprising a stack of x battery cells according to the first aspect of the present invention, where x is 2 to 20, preferably 2 to 10, for example 2 to 5.

[0047] Advantages of the battery cells of the present disclosure include, but are not limited to, extended lifespan. In particular, the battery cells of the present invention can be charged and discharged multiple times, thereby resulting in extended lifespan. A further advantage is that compared to current state-of-the-art battery cells, they have superior conductivity and coulombic efficiency without metal loss. Aspects of the present invention will now be described in more detail with reference to the accompanying drawings, in which like reference numerals refer to like features, and in which: [Brief explanation of the drawings]

[0048] [Figure 1] FIG. 1 shows a schematic diagram of an anode-free metal battery cell according to the present invention. [Figure 2] FIG. 1 shows a schematic diagram of another anode-free metal battery cell according to the present invention. [Figure 3] 1 shows a schematic diagram of a battery cell containing an anode according to the present invention. [Figure 4] 1 shows a schematic diagram of another negative electrode-containing battery cell according to the present invention. [Figure 5] FIG. 1 shows a schematic diagram of yet another anode-free metal battery cell according to the present invention. [Figure 6] 1 shows a schematic diagram of a further anode-free metal battery cell according to the present invention. [Figure 7] 1 shows a schematic diagram of yet a further anode-free metal battery cell according to the present invention. [Figure 8] 1 shows the voltage of an anode-free battery cell of the present invention as a function of specific charge per gram of active material. [Figure 9] 1 shows the voltage of a battery cell containing a negative electrode of the present invention as a function of specific charge per gram of active material upon repeated charging and discharging of the battery cell. [Figure 10] 1 shows the specific charge per gram of active material of battery cells containing two types of negative electrodes of the present invention as a function of the number of charge-discharge cycles. [Figure 11] 1 shows the specific charge per gram of active material of battery cells containing two types of negative electrodes of the present invention as a function of the number of charge-discharge cycles. [Figure 12] 1 shows the voltage of a battery cell containing a negative electrode of the present invention as a function of specific charge per gram of active material. DETAILED DESCRIPTION OF THE INVENTION

[0049] 1 shows a schematic diagram of a first embodiment of a battery cell 100 of the present invention. The battery cell 100 includes a positive electrode current collector 1, a positive electrode 2, a solid electrolyte 3, and a negative electrode current collector 4. The battery cell 100 does not include a negative electrode, i.e., the battery cell 100 is an anode-free metal battery cell. As is known in the art, during the first charge of an anode-free metal battery cell, a metal layer is formed (deposited) in situ on the negative electrode current collector as a negative electrode.

[0050] In this disclosure, the terms anode-free metal battery cell and anode-free battery cell are used interchangeably. Advantageously, the "metal" in an anode-free metal battery cell refers to the metal present in the positive electrode, i.e., the ions of the metal of the positive electrode, i.e., the metal ions pass through the electrolyte for in-situ deposition of the negative electrode layer on the negative electrode current collector.

[0051] Advantageously, the metal is an alkali metal, an alkaline earth metal, or a metal from group Ib, IIb, or IIIa of the periodic table. Advantageously, the alkali metal is lithium or sodium. Advantageously, the alkaline earth metal is magnesium. Advantageously, the group Ib metal is silver (Ag) or gold (Au). Advantageously, the group IIb metal is zinc (Zn) or cadmium (Cd). Advantageously, the group IIIa metal is aluminum (Al). Preferred examples of metals include lithium, sodium, magnesium, and aluminum.

[0052] Advantageously, the positive electrode current collector 1 is as described herein above. Advantageously, the positive electrode current collector 1 extends from the anode-free battery cell 100, as is known in the art. In other words, the positive electrode current collector 1 advantageously has a portion that extends from the stack including the positive electrode 2, the electrolyte 3, and the negative electrode current collector 4. This can be achieved by methods known in the art, for example, by providing the positive electrode current collector 1 with a surface area that is greater than the surface area of ​​the positive electrode 2. As is known, such an extension advantageously allows the positive electrode current collector 1 to be easily connected or coupled to electronic circuitry (not shown) to which the negative electrode current collector 4 is also connected or coupled.

[0053] Advantageously, the positive electrode 2 is as described hereinbefore. Advantageously, the active material comprises or consists essentially of an alkali metal, an alkaline earth metal, or a metal from Group Ib, Group IIb, or Group IIIa of the periodic table. Advantageously, the alkali metal is lithium or sodium. Advantageously, the alkaline earth metal is magnesium. Advantageously, the Group Ib metal is silver (Ag) or gold (Au). Advantageously, the Group IIb metal is zinc (Zn) or cadmium (Cd). Advantageously, the Group IIIa metal is aluminum (Al). Preferred examples of metals include lithium, sodium, magnesium, and aluminum.

[0054] Alternatively or additionally, and advantageously, the active material comprises or consists essentially of an alkali metal, alkaline earth metal, or Group Ib, IIb, or IIIa metal-based intercalation compound of the periodic table. Non-limiting examples of intercalation compounds include lithium iron phosphate (LFP) and sodium iron phosphate (NFP). Further non-limiting examples of active materials are lithium nickel cobalt aluminum oxide (NCA), lithium nickel cobalt manganese oxide (NMC), lithium manganese oxide (LMO), lithium nickel manganese oxide (LNMO), and lithium cobalt oxide (LCO).

[0055] Advantageously, the positive electrode comprises 25% to 99.7% by weight, for example 40% to 99.5% by weight, preferably 50% to 99% by weight, for example 60% to 97.5% by weight, more preferably 75% to 95% by weight, of active material, based on the total weight of the positive electrode.

[0056] Advantageously, the electronically conductive material comprises carbon, such as carbon fibers, carbon nanotubes, particulate carbon (e.g., powder), or a combination of two or more thereof. Advantageously, the electronically conductive material is a carbon-based electronically conductive material, such as graphite.

[0057] Advantageously, the positive electrode comprises 0.1% to 30% by weight, for example 0.25% to 25% by weight, preferably 0.5% to 20% by weight, for example 1% to 15% by weight, more preferably 2% to 10% by weight of electronically conductive material, based on the total weight of the electrode.

[0058] Advantageously, the binder comprises or consists essentially of rubbers such as styrene butadiene rubber (SBR) or latex, polyvinylidene fluoride (PVDF) and polyvinylpyrolidone (PVP), especially high molecular weight PVP.

[0059] Advantageously, the positive electrode comprises 0.1% to 30% by weight, for example 0.25% to 25% by weight, preferably 0.5% to 20% by weight, for example 0.75% to 15% by weight, more preferably 1% to 10% by weight of binder, based on the total weight of the positive electrode.

[0060] The solid electrolyte 3 is advantageously as described hereinbefore and comprises a non-aqueous solvent, an aluminum-based halide compound AlX n and / or polymeric versions thereof, metal salts of alkali metals, alkaline earth metals, or metals in Group Ib, IIb, or IIIa of the periodic table, and bis(fluorosulfonyl)imide (FSI) anions, wherein X is a halogen atom and n is 1 to 6.

[0061] The metal contained in the active material of the positive electrode 2 and the metal contained as the cation of the metal salt in the SSE 3 may be the same or different. Advantageously, they are the same. For example, but not limited to, a battery cell can contain lithium cobalt oxide (LiCoO) as the active material of the positive electrode and LiFSI as the metal salt of the solid electrolyte.

[0062] Advantageously, the negative electrode current collector 4 comprises or consists essentially of at least one metal. Advantageously, the metal is copper, a copper alloy, nickel, a nickel alloy, steel, or lithium. The steel may be, but is not limited to, stainless steel or carbon steel.

[0063] Advantageously, the negative electrode current collector 4 extends from the anode-free battery cell 100. In other words, the negative electrode current collector 4 advantageously has a portion that extends from the laminate including the positive electrode current collector 1, the positive electrode 2, and the solid electrolyte 3. Such an extension advantageously allows the negative electrode current collector 4 to be easily connected or coupled to an electronic circuit (not shown) to which the positive electrode current collector 1 is also connected or coupled.

[0064] 2 shows a schematic diagram of a second embodiment of a battery cell 101 of the present disclosure that does not include a negative electrode, i.e., is an anode-free battery cell. The anode-free metal battery cell 101 includes a positive electrode current collector 1. Advantageously, the positive electrode current collector 1 is as described hereinabove. The battery cell 101 further includes a positive electrode 2. Advantageously, the positive electrode 2 is as described hereinabove. The battery cell 101 further includes a negative electrode current collector 4. Advantageously, the negative electrode current collector 4 is as described hereinabove. The anode-free battery cell 101 also includes a solid electrolyte 3. The solid electrolyte 3 is as described hereinabove.

[0065] The anode-free metal battery cell 101 further comprises a separator 5. Advantageously, the separator 5 is as described herein above. Advantageously, the separator 5 is a separator membrane, i.e., a battery separator membrane. The separator 5 may be a porous separator membrane.

[0066] Advantageously, separator 5 comprises or consists essentially of at least one polymer. Advantageously, alternatively or additionally, battery separator membrane 5 is a ceramic material. For example, separator 5 can comprise a ceramic-filled polymer.

[0067] Non-limiting examples of suitable polymers include polypropylene (PP), polyethylene (PE), polytetrafluoroethylene (PTFE), and polyvinylidene fluoride (PVDF). PP, PE, PTFE, and PVDF are preferred materials due to their chemical inertness. However, they are not easily wetted, while the porous separator preferably absorbs the liquid electrolyte. For this purpose, PP, PE, PTFE, and / or PVDF can be treated with a surface treatment or coating, such as spray coating, dip coating, or plasma coating (atmospheric or low-pressure plasma).

[0068] The separator can include one or more layers. A multi-layer separator of particular interest is a three-layer PVDF-PE-PVDF separator, optionally filled with ceramic.

[0069] 3 shows a schematic diagram of a further battery cell 102 of the present disclosure. The battery cell 102 advantageously includes a positive electrode current collector 1, which is as previously described herein. The battery cell 102 further advantageously includes a positive electrode 2, which is as previously described herein. The battery cell 102 also includes a solid electrolyte 3, which is as previously described herein. The battery cell 102 also includes an anode current collector 4, which is advantageously as previously described herein.

[0070] The battery cell 102 further includes an anode 12, i.e., the battery cell 102 is an anode-containing battery cell. The anode 12 is advantageously as described herein above.

[0071] Advantageously, the negative electrode comprises or essentially consists of a metal layer. The metal of the metal layer may be the same as or different from the metal contained in the positive electrode, for example, one of the metals contained in the active material of the positive electrode. Furthermore, the metal of the metal layer may be the same as or different from the metal of the metal salt of the solid electrolyte. Advantageously, at least one metal of the metal layer is the same as the metal of the positive electrode. For example, if the positive electrode comprises lithium, the negative electrode is advantageously a metal layer comprising or essentially consisting of lithium.

[0072] Alternatively, and more advantageously, the negative electrode comprises or consists essentially of an intercalation negative electrode. Non-limiting examples of suitable intercalation electrodes include graphite and Li4Ti5O 12 or a combination thereof.

[0073] Alternatively, and more advantageously, the negative electrode comprises or consists essentially of a conversion electrode. Advantageously, the conversion electrode comprises or consists essentially of an oxide, a nitride, a sulfide, or a combination of two or more thereof. Non-limiting examples of oxides include LiVO2 and SnO2. Non-limiting examples of nitrides include vanadium nitride (VN) and molybdenum nitride (δ-MoN). Non-limiting examples of sulfides include tin sulfide (SnS x ) and vanadium sulfides (VS2 and VS4).

[0074] Advantageously, the negative electrode can be obtained by means known in the art, such as by forming a film, sheet or foil, or by depositing layers by known methods such as sputtering and plasma deposition.

[0075] 4 shows a schematic diagram of an anode-containing battery cell 103 of the present disclosure. The battery cell 103 advantageously includes a cathode current collector 1, a cathode 2, a solid electrolyte 3, an anode current collector 4, an anode 12, and a separator 5, all as previously described herein.

[0076] 5 shows a schematic diagram of a third embodiment of an anode-free metal battery cell 104 of the present disclosure. The anode-free metal battery cell 104 advantageously includes a positive electrode current collector 1, a positive electrode 2, and a solid electrolyte 3, all as previously described herein. The battery cell 104 may further include a separator (not shown).

[0077] The battery cell 104 further comprises an electron conductor 10. The electron conductor 10 is advantageously as described hereinabove. The electron conductor 10 advantageously functions as a negative electrode current collector.

[0078] Advantageously, the electronic conductor 10 comprises or consists essentially of at least one metal. Advantageously, the metal is copper, a copper alloy, nickel, a nickel alloy, lithium, a lithium alloy, or steel. The steel may be, but is not limited to, stainless steel or carbon steel. For example, the electronic conductor may comprise a nickel-plated copper foil.

[0079] Alternatively, and alternatively or additionally, the electron conductor 10 comprises or consists essentially of a polymer. Preferred examples of polymers include, but are not limited to, poly(3,4-ethylenedioxythiophene) (PEDOT) and polyaniline.

[0080] Alternatively, and alternatively or additionally, the electron conductor 10 comprises or consists essentially of carbon. Preferred examples of carbon include, but are not limited to, carbon black, carbon nanotubes, graphite, or a combination of two or more thereof.

[0081] Alternatively, and alternatively or additionally, the electronic conductor 10 comprises or consists essentially of one or more of an oxide, a sulfide, a nitride, a carbide, or a silicide.

[0082] The anode-free metal battery cell 104 further includes a high surface area substrate 6. Advantageously, the high surface area substrate 6 is provided on the negative electrode side of the battery cell 104. In other words, the high surface area substrate 6 is advantageously provided on the electrolyte 3 side opposite the positive electrode 2.

[0083] Advantageously, the high surface area substrate 6 is provided such that at least a part of its (external) surface 7 is in contact with at least a part of the surface 8 of the electron conductor 10. Advantageously, the surface 7 of the high surface area substrate 6 that is at least partially in contact with the electron conductor 10 is different from the surface that is in contact with the SSE 3.

[0084] Advantageously, the high surface area substrate 6 has a porosity of at least 40% as measured by X-ray computed tomography. In light of the present disclosure, "at least 40% porosity" means that the high surface area substrate 6 has a porosity of at least 40% across all portions or regions of the substrate 6.

[0085] Advantageously, the high surface area substrate 6 comprises or consists essentially of an organic compound. Advantageously, the organic compound comprises or consists essentially of a polymer, i.e., is a polymer. Alternatively and advantageously, the organic compound comprises or consists essentially of a polymorph of carbon, i.e., is a polymorph of carbon.

[0086] Advantageously, the polymer is selected from the group consisting of cellulose, regenerated cellulose (viscose), polypropylene, polyethylene, polyvinylidene difluoride, polytetrafluoroethylene, polyurethane, aramid, and silk. Further examples of organic compounds include wool and polyaramid.

[0087] Non-limiting examples of polymorphs of carbon include graphene, carbon nanotubes, graphite, hard carbon, and carbon black.

[0088] Advantageously, additionally or alternatively, the high surface area substrate comprises or consists essentially of an inorganic compound. Advantageously, the inorganic compound comprises or consists essentially of lithium lanthanum zirconium oxide (LLZO) and / or silica polymorphs. Non-limiting examples of silica polymorphs include quartz, cristobalite, tridymite, coesite, stishovite, lechatelierite, and opal.

[0089] The high surface area substrate 6 can include or consist of a single layer, or can include multiple layers, i.e., two or more layers. When the high surface area substrate 6 includes two or more layers, they can be the same or different. For example, they can have the same or different composition, structure, shape, thickness, or porosity. Advantageously, each layer has a porosity of at least 40% as measured by X-ray tomography.

[0090] The high surface area substrate 6 may have any shape, size, or configuration, so long as it is a substrate having a high surface area. Advantageously, the high surface area substrate 6 is in the form of a film, foam, nonwoven, woven, or knitted fabric. Advantageously, the film and foam are open-cell film and foam.

[0091] 6 shows another anode-free metal battery cell 105 according to the present disclosure. The anode-free metal battery cell 105 advantageously includes a positive electrode current collector 1, a positive electrode 2, a solid electrolyte 3, an electronic conductor 10, and a high surface area substrate 6, all as previously described for FIG. 5 herein.

[0092] Advantageously, the battery cell 105 further includes a negative electrode lead extension 9. The negative electrode lead extension 9 advantageously extends from the anode-free battery cell 105 as previously described herein for the negative electrode current collector.

[0093] Advantageously, the negative electrode lead extension 9 comprises or consists essentially of at least one metal. Advantageously, the metal is copper, a copper alloy, nickel, a nickel alloy, steel, or lithium. The steel may be, but is not limited to, stainless steel or carbon steel.

[0094] Advantageously, at least a portion of surface 8 of electron conductor 10 contacts at least a portion of surface 7 of high surface area substrate 6. Advantageously, surface 7 of high surface area substrate 6 that is at least partially in contact with electron conductor 10 is different from the surface of high surface area substrate 6 that is in contact with electrolyte 3.

[0095] Advantageously, at least a portion of the surface of the electron conductor 10 is in contact with at least a portion of the surface of the negative electrode lead extension 9 .

[0096] 7 shows another anode-free metal battery cell 106 according to the present disclosure. The anode-free metal battery cell 106 advantageously includes a positive electrode current collector 1, a positive electrode 2, a solid electrolyte 3, a separator 5, a high surface area substrate 6, a negative electrode lead extension 9, and an electronic conductor 10, all as previously described herein.

[0097] Example Example 1 A liquid precursor was prepared by adding 12.65 g of LiFSI as a first metal salt, 19.42 g of LiTFSI as a second metal salt, 3.00 g of AlCl, and 2.02 g of HFE as a surfactant to 20.25 g of DME as a non-aqueous solvent.

[0098] The anode-free battery cells were prepared as bi-stack pouch cells containing two copper foils as negative current collectors sandwiching a positive electrode containing NCA as the active material. A three-layer ceramic separator, consisting of one layer of polyethylene sandwiched between two layers of polyvinylidene fluoride, was placed between the positive and negative current collectors.

[0099] The liquid precursor was then prepared in an anode-free battery cell and maintained at 60 °C for 24 h to convert the liquid precursor into a solid electrolyte. The SSE contained 22.07 wt% LiFSI, 33.87 wt% LiTFSI, 5.23 wt% AlCl, 3.53 wt% HFE, and 35.31 wt% DME, based on the total weight of the SSE.

[0100] Next, the battery cell was charged and discharged at 5 mA using a galvanostatic method (0.39 mA / cm on the positive electrode surface). 2 ), the cell potential was measured at room temperature as a function of the specific charge per gram of active material. The results are shown in Figure 8, where line 13 represents the charge curve and line 14 represents the discharge curve. It is clear from Figure 8 that 158 ​​mAh / g of the predicted 170 mAh / g is usable. In other words, only 12 mAh / g is lost during the initial in situ lithium deposition.

[0101] Example 2 A liquid precursor was prepared by adding 16.00 g of LiFSI as a metal salt, 2.66 g of AlCl, and 2.00 g of HFE as a surfactant to 8.00 g of acetonitrile (ACN). The liquid precursor was then kept at a temperature of 20 °C for 24 hours to obtain a solid electrolyte (SSE).

[0102] The SSE contained 55.83 wt% LiFSI, 9.28 wt% AlCl3, 6.98 wt% HFE, and 27.91 wt% ACN, based on the total weight of the SSE.

[0103] The first battery cell (containing the negative electrode) was prepared as a bi-stack pouch cell, with aluminum foil (Al) as the positive electrode current collector sandwiched between two lithium iron phosphate (LFP) positive electrodes. A copper foil as the negative electrode current collector was attached to both sides of the LFP-Al-LFP composite, with a 50 μm-thick lithium foil as the negative electrode. A three-layer ceramic separator, consisting of one layer of polyethylene sandwiched between two layers of polyvinylidene fluoride, was placed between each positive electrode and one negative electrode (for a total of two separators).

[0104] The negative and positive electrodes were impregnated with the solid electrolyte by spreading it onto the negative and positive electrode substrates with a spatula until the entire surface was evenly coated with the SSE.

[0105] The first battery cell was then subjected to 10 charge-discharge cycles at 0.25 mA / cm between 3.0 V and 3.8 V. 2 The test was carried out using a galvanostat method under positive electrode surface conditions.

[0106] Figure 9 shows the voltage as a function of the specific charge per gram of active material for charge-discharge cycling, where 15 represents the charge curve and 16 represents the discharge curve. It is clear that the charge-discharge cycles are very stable over 10 cycles.

[0107] Example 3 A suspension was prepared by adding 10.02 g of LiFSI as a metal salt, 1.90 g of AlCl3, and 1.25 g of HFE as a surfactant to 10.00 g of DME as a non-aqueous solvent.

[0108] Next, this suspension was heated at 60°C for 10 minutes to obtain a liquid precursor, which was then kept at a temperature of 20°C for 24 hours to obtain a solid electrolyte (SSE).

[0109] The SSE contained 43.24 wt% LiFSI, 8.20 wt% AlCl3, 5.40 wt% HFE, and 43.16 wt% DME, based on the total weight of the SSE.

[0110] The second battery cell (containing the negative electrode) was prepared as a bi-stack pouch cell, with aluminum foil (Al) as the positive electrode current collector sandwiched between two lithium iron phosphate (LFP) positive electrodes. Copper foils as negative electrode current collectors were attached to both sides of the LFP-Al-LFP composite, with 50 μm-thick lithium foils as the negative electrodes. Separators containing a three-layer ceramic, consisting of one layer of polyethylene sandwiched between two layers of polyvinylidene fluoride, were placed between the positive and negative electrodes (for a total of two separators).

[0111] The negative and positive electrodes were impregnated with the solid electrolyte by spreading it onto the negative and positive electrode substrates with a spatula until the entire surface was evenly coated with the SSE.

[0112] The first battery cell was then subjected to 20 charge-discharge cycles at 0.25 mA / cm between 3.0 V and 3.8 V. 2 The test was carried out using a galvanostat method under positive electrode surface conditions.

[0113] 10 shows the specific charge per gram of active material for the first battery cell of Example 2 and the second battery cell of Example 3 as a function of the number of charge-discharge cycles. It is clear that the negative electrode capacity 17, representing the charging of the (first) battery cell, and the positive electrode capacity 18, representing the discharging of the (first) battery cell, for the first battery cell using ACN as the non-aqueous solvent, are very close and remain substantially constant for at least 20 charge-discharge cycles. The negative electrode capacity 19, representing the charging of the (second) battery cell, and the positive electrode capacity 20, representing the discharging of the (second) battery cell, for the second battery cell using DME as the non-aqueous solvent, are slightly lower compared to the first battery cell, but they also remain stable with each additional charge-discharge cycle, up to at least 20 cycles.

[0114] Example 4 A liquid precursor was prepared by adding 10.00 g of LiFSI as a metal salt, 2.01 g of AlCl 3 and 2.50 g of HFE as a surfactant to 20.00 g of DME as a non-aqueous solvent.

[0115] A 900 mAh stacked negative electrode-containing battery cell was prepared using five layers of LFP-Al-LFP (i.e., aluminum foil (Al) as a positive electrode current collector sandwiched between two lithium iron phosphate (LFP) positive electrodes). Six LFP-Al-LFP composites were prepared, each containing a 25 μm-thick lithium foil as a negative electrode current collector and a 13 μm-thick copper foil as a negative electrode current collector. A three-layer ceramic separator, consisting of one layer of polyethylene sandwiched between two layers of polyvinylidene fluoride, was placed between each positive and negative electrode. The liquid precursor was then prepared in a battery cell and maintained at 60 °C for 48 hours to convert the liquid precursor into a solid electrolyte. The SSE contained 28.99 wt% LiFSI, 5.82 wt% AlCl, 7.24 wt% HFE, and 57.95 wt% DME, based on the total weight of the SSE.

[0116] Next, the battery cell was galvanostatically charged between 3.0 V and 3.8 V at 120 mA (0.25 mA / cm on the positive electrode surface). 2) charged and discharged.

[0117] 11 shows the specific charge per gram of active material of the battery cell as a function of the number of charge-discharge cycles. It is clear that the negative electrode capacity 21, which represents the charging of the battery cell, and the positive electrode capacity 22, which represents the discharging of the battery cell, are very close and remain substantially constant for at least seven charge-discharge cycles. The difference in the negative and positive electrode capacities for the first cycle can be explained by the known fact that a portion of the first cycle capacity in electrochemical systems is irreversible.

[0118] Figure 12 shows the battery cell voltage as a function of the specific charge per gram of active material for the first charge (line 23) and subsequent discharge (line 24). The results clearly demonstrate the scalability of solid-state battery cells. [Explanation of symbols]

[0119] 1 Positive electrode current collector 2 Positive electrode 3 Solid electrolyte 4 Negative electrode current collector 5 Separator 6 High surface area substrate 7. High surface area substrate surface 8. Surface of negative electrode current collector 9 Negative lead extension 10 Electronic conductors 12 Negative electrode 13 Charging curve of an anode-free battery cell 14 Discharge curve of an anode-free battery cell 15 Charging curve of the first negative electrode-containing battery cell 16 Discharge curve of the first negative electrode-containing battery cell 17 Negative electrode capacity of first negative electrode-containing battery cell 18 Positive electrode capacity of first negative electrode-containing battery cell 19 Negative electrode capacity of second negative electrode-containing battery cell 20 Positive electrode capacity of second negative electrode-containing battery cell 21 Negative electrode capacity of battery cells containing laminated negative electrodes 22 Positive electrode capacity of battery cells containing stacked negative electrodes 23 Charging curve of battery cell containing stacked negative electrode 24 Discharge curve of battery cell containing stacked negative electrode 100 Anode-free Metal Battery Cells 101 Anode-free metal battery cells 102 Battery cell containing negative electrode 103 Battery cell containing negative electrode 104 Anode-free Metal Battery Cells 105 anode-free metal battery cells 106 anode-free metal battery cells

Claims

1. A battery cell (100, 101, 102, 103, 104, 105, 106) comprising a positive electrode current collector (1), a positive electrode (2), a solid electrolyte (3), and further comprising an electron conductor (10) functioning as a negative electrode current collector (4) or a negative electrode current collector, The solid electrolyte (3) is a non-aqueous solvent, an aluminum-based halide compound AlX ｎ a metal salt of a polymeric alkali metal, alkaline earth metal, or metal from Group Ib, IIb, or IIIa of the periodic table, and a bis(fluorosulfonyl)imide (FSI) anion, wherein X is a halogen atom and n is 1 to 6.

2. 2. The battery cell (100, 101, 102, 103, 104, 105, 106) of claim 1, wherein the metal is lithium, sodium, magnesium, aluminum, zinc, or silver.

3. X is Cl, n is 3, and the aluminum-based halide compound is AlCl ３ The battery cell (100, 101, 102, 103, 104, 105, 106) according to claim 1,

4. 10. The battery cell (100, 101, 102, 103, 104, 105, 106) of claim 1, wherein the metal salt comprises two or more anions, and one of the anions of the metal salt is the FSI.

5. The method further comprises at least one additional metal salt comprising an anion, wherein the anion of the at least one additional metal salt is selected from the group consisting of bis(trifluoromethane)sulfonimide (TFSI), dicyanamide (DCA), perchloric acid (ClO ４ ), difluorobis(oxalato)borate (DFOB) or hexafluorophosphate (PF ６ The battery cell (100, 101, 102, 103, 104, 105, 106) according to claim 4,

6. 10. The battery cell (100, 101, 102, 103, 104, 105, 106) of claim 1, wherein the non-aqueous solvent is acetonitrile, dimethoxyethane, or an ionic liquid.

7. 10. The battery cell (100, 101, 102, 103, 104, 105, 106) of claim 1, wherein the non-aqueous solvent is an ionic liquid containing an anion, and the anion of the ionic liquid is the FSI.

8. 10. The battery cell (101, 103, 106) of claim 1, further comprising a separator (5) between the positive electrode (2) and the negative electrode current collector (4) or the electronic conductor (10).

9. A battery cell (102, 103) as described in claim 1, further comprising a negative electrode (12) between the solid electrolyte (3) and the negative electrode current collector (4).

10. 10. The battery cell (102, 103) of claim 9, wherein the negative electrode (12) comprises a metal layer comprising an alkali metal, an alkaline earth metal, or a metal from Group Ib, IIb, or IIIa of the periodic table, or a combination of two or more thereof.

11. 10. The battery cell (102, 103) of claim 9, wherein the negative electrode (12) comprises an intercalation electrode or a conversion electrode, the conversion electrode comprising an oxide, a nitride, a sulfide, or a combination of two or more thereof.

12. 2. The battery cell (104, 105, 106) of claim 1, further comprising a high surface area substrate (6) disposed between the positive electrode (2) and the negative electrode current collector (4) or the electronic conductor (10), wherein at least a portion of a surface (7) of the high surface area substrate (6) is in contact with at least a portion of a surface of the negative electrode current collector (4) or the electronic conductor (10).

13. 13. The battery cell (105, 106) of claim 12, comprising an electron conductor (10) and further comprising a negative electrode lead extension (9), wherein at least a portion of a surface of the electron conductor (10) is in contact with at least a portion of a surface of the negative electrode lead extension (9).

14. The battery cell (100, 101, 102, 103, 104, 105, 106) according to claim 1, wherein the battery cell (100, 101, 102, 103, 104, 105, 106) is a secondary battery cell.

15. A battery comprising a stack of x battery cells (100, 101, 102, 103, 104, 105, 106) according to claim 1, wherein x is between 2 and 20.

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