Battery cell

Abstract

The present invention relates to battery cells comprising a cathode current collector, a cathode, an anode current collector, optionally an anode, and a non-aqueous solvent, an aluminum-based halogenated compound AlXn and / or its polymer form, wherein X is a halogen atom and n is between 1 and 6, said aluminum-based halogenated compound AlXn and / or its polymer form, a metal salt of an alkali metal, an alkaline earth metal or a metal of group Ib, group IIb or group IIIa of the periodic table, and a solid electrolyte comprising a bis(fluorosulfonyl)imide anion.

Description

Technology Field

[0001] The present invention relates to battery cells and batteries comprising a solid-state electrolyte. Background Technology

[0002] Recently, the development and improvement of batteries for various devices requiring batteries, such as mobile phones, wireless home appliances, electric vehicles, and bicycles, have become important areas of research and interest. In particular, the field of rechargeable batteries has been enhanced by the development of smaller and lighter batteries, resulting in improved lifespans.

[0003] According to these recent developments, lithium secondary batteries having lithium metal as an active material are attracting attention. Lithium metal is known to have characteristics such as a low redox potential (-3.045 V vs. standard hydrogen electrode) as well as a high gravimetric energy density (3860 mAh / g), which makes lithium metal an interesting material for the anode.

[0004] It is known that lithium metal is used as the negative electrode by attaching lithium foil to the anode current collector. However, since lithium is an alkali metal, it reacts with water and oxygen due to its high reactivity. This presents a disadvantage, as such batteries are considered unsafe due to the risk of explosion in the event of an environmental leak, for instance. Additionally, handling the lithium foil is also dangerous.

[0005] Furthermore, when lithium metal is exposed to the atmosphere, an oxide layer typically forms as a result of oxidation. This oxide layer tends to act as an insulator, increasing electrical resistance and consequently reducing battery performance.

[0006] To solve these problems, anode-free battery cells have been developed. These battery cells typically contain only an anode current collector, and a lithium layer as an anode is formed (deposited) in-situ on the anode current collector during the first charge of the battery.

[0007] US2016 / 0261000 discloses an anode-free rechargeable battery comprising an anode current collector, a separator, and a cathode. The battery further comprises a liquid electrolyte comprising a salt or a salt mixture comprising an active metal cation (e.g., lithium ion) dissolved in a non-aqueous solvent, a solvent mixture, or a polymer. The electrolyte may be injected into the separator. During charging of the battery, an anode is formed in situ on the surface of the anode current collector.

[0008] A disadvantage of the aforementioned electrolyte is that the electrolyte is liquid, which can lead to leakage of the electrolyte from the battery and result in a loss of functionality. Another disadvantage is that metal (e.g., lithium) ions may interact with the solvent, which can reduce the amount of ions available for the deposition of the anode layer in situ and for charging and discharging the battery.

[0009] US2020 / 0203757 discloses a lithium secondary battery comprising a positive electrode, a negative electrode current collector, a separator, and an electrolyte interposed between the electrodes. The electrolyte is a gel polymer electrolyte and may be cross-linked. The gel polymer electrolyte comprises a polymer matrix and a lithium salt dissolvent in an organic solvent. A lithium metal layer is formed in situ on the negative electrode current collector during charging.

[0010] A disadvantage of gel polymer electrolytes is that their lithium ion conductivity is typically known to be low, such as less than 1 mS / cm. The problem to be solved

[0011] The object of the present invention is to overcome one or more of the aforementioned disadvantages. The object of the present invention is to provide a battery cell having improved functionality compared to battery cells in the art.

[0012] The objective is to provide a battery cell that can withstand multiple charge / discharge cycles and exhibits excellent conductivity. means of solving the problem

[0013] According to a first aspect of the present invention, a battery cell as set forth in the appended claims is provided.

[0014] A battery cell includes a cathode current collector, a cathode, a solid electrolyte, and an anode current collector or electronic conductor.

[0015] The cathode current collector may be any cathode current collector known in the art. For example, the cathode current collector may include or substantially consist of aluminum.

[0016] Advantageously, the cathode comprises an active material. Advantageously, the active material comprises or is substantially composed of one or more of alkali metals, alkaline earth metals, or metals of Group Ib, Group IIb, or Group IIIa of the periodic table.

[0017] Advantageously, the cathode further comprises an electronically conductive compound. The electronically conductive compound may be any electrically conductive compound known in the art.

[0018] Advantageously, the cathode further comprises a binder. The binder may be any binder known in the art.

[0019] Preferably, the solid electrolyte is a non-aqueous solvent, an aluminum-based halogenated compound AlX nand / or polymer forms thereof, metal salts and bis(fluorosulfonyl)imide (FSI) anions.

[0020] Advantageously, the metal salt is a metal salt of an alkali metal, an alkaline earth metal, or a metal of Group Ib, Group IIb, or Group IIIa of the periodic table. Advantageously, the metal of the metal salt is lithium, sodium, magnesium, aluminum, zinc, or silver. In other words, the metal salt is advantageously a lithium salt, sodium salt, magnesium salt, aluminum salt, zinc salt, or silver salt.

[0021] The metal of the metal salt may be the same or different from the metal contained in the cathode. If the solid electrolyte (SSE) contains two or more metal salts, their metals may be the same or different and may be the same or different from the metal contained in the cathode. For example, the SSE may contain two lithium salts, or a combination of a lithium salt and a magnesium salt, but is not limited thereto.

[0022] Advantageously, and as is known, metal salts contain anions. As is known, metal salts also advantageously contain cations. Advantageously, said cations are cations of the metal of the metal salt. For example, if the metal salt is a lithium salt, the cation is a lithium cation (Li + )am.

[0023] The solid electrolyte is an aluminum-based halide compound, AlX n and / or further comprises a polymeric form thereof, wherein X is a halogen atom. Advantageously, n is between 1 and 6, e.g., between 1 and 3. Advantageously, X is a chloride, bromide, or iodide, preferably a chloride. Advantageously, AlX n The polymer form of (AlX n ) m and, where m is 2 or greater.

[0024] Advantageously, X is a chloride and n is 3, and the aluminum halide compound is AlCl3. Advantageously, X is a chloride, n is 3 and m is 2 or more, and the polymer form of the aluminum halide compound is (AlCl3) m am.

[0025] The solid electrolyte further comprises bis(fluorosulfonyl)imide (FSI) anions. Surprisingly, the inventors found that the presence of FSI anions in SSE corresponds to the aluminum-based halide compound AlX n It was discovered that it enables the maintenance of solid-state properties of electrolytes including and / or their polymer forms.

[0026] Advantageously, and according to a first embodiment of the solid electrolyte of the battery cells of the present disclosure, the anion of the metal salt is FSI. For example, if the metal of the metal salt is lithium (Li), the metal salt is advantageously LiFSI.

[0027] Where the SSE of the first embodiment comprises at least one additional metal salt, the anion of the at least one additional metal salt is advantageously FSI, bis(trifluoromethane)sulfonimide (TFSI), dicyanamide (DCA), perchlorate (ClO4), tetrachloroaluminate (AlCl4), difluorobis(oxalato)borate (DFOB), or hexafluorophosphate (PF6). Additional examples include, but are not limited to, difluorobis(oxalato)phosphate (DFBOP), tetrafluoroborate (BF4), hexafluoroarsenide (AsF6), tetrachloroaluminate (AlCl4), trifluoromethanesulfonate (CF3SO3), and (fluoromethylsulfonyl)(trifluoromethylsulfonyl)imide (FTFSI). For example, SSE may include two types of metal salts having different cations and both having FSI as anion, for example, LiFSI and NaFSI.

[0028] Advantageously, when at least one anion of the metal salt or two or more metal salts is FSI, the non-aqueous solvent(s) are selected from the group consisting of nitriles, ethers, esters, carbonates, sulfones, amides, and ionic liquids. Preferred examples of the non-aqueous solvent(s) include, but are not limited to, acetonitrile, dimethoxyethane, and ionic liquids. Additional examples include propylene carbonate, ethylene carbonate, tetrahydrofuran, diethyl carbonate, γ-butyrolactone, 2-methyltetrahydrofuran, 1-3-dioxolane, tetramethylsulfone (sulfolane), and dimethylsulfone (DMSO2).

[0029] Ionic liquids are known in the art as salts in liquid form at suitable temperatures without the need for the salt to be dissolved in another solvent. Ionic liquids typically consist of ions—cations and anions. Advantageously, when the non-aqueous solvent is an ionic liquid, it contains organic cations and inorganic or organic anions.

[0030] Advantageously, and according to a second embodiment of the solid electrolyte of the battery cells of the present disclosure, the non-aqueous solvent is an ionic liquid, wherein the anion of the ionic liquid is FSI.

[0031] In the case where 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. Additional examples include propylene carbonate, ethylene carbonate, tetrahydrofuran, diethyl carbonate, γ-butyrolactone, 2-methyltetrahydrofuran, 1-3-dioxolane, tetramethylsulfone, and dimethylsulfone.

[0032] If one of the second or additional non-aqueous solvents is an ionic liquid, its anion is advantageously TFSI, DCA, ClO4, PF6, DFBOP, DFOB, BF4, FTFSI, AlCl4, AsF6, or CF3SO3. For example, SSE may comprise two types of ionic liquids as non-aqueous solvents, each having FSI as an anion and different cations. Alternatively, each ionic liquid may have different anions—one of which is FSI—and the same cation.

[0033] Advantageously, where a non-aqueous solvent or at least one of two or more non-aqueous solvents is an ionic liquid having an FSI anion, the anions of the metal salt(s) of SSE are TFSI, DCA, ClO4, PF6, DFBOP, DFOB, BF4, FTFSI, AlCl4, AsF6, and CF3SO3.

[0034] A third embodiment of the solid electrolyte of the battery cell of the present invention comprises a combination of the first and second embodiments. In other words, according to the third embodiment, at least one anion of a metal salt or two or more metal salts is FSI and a non-aqueous solvent, or at least one of two or more non-aqueous solvents is an ionic liquid, and the anion thereof is FSI.

[0035] Advantageously, the battery cell further comprises a separator, such as a separator membrane, provided between the cathode and the anode current collector. The separator may be any separator known in the art.

[0036] Optionally, the battery cell further comprises an anode, that is, the battery cell is an anode containing the battery cell. The anode may be any anode known in the art.

[0037] Advantageously, the anode comprises or is substantially composed of a metal layer comprising an alkali metal, an alkaline earth metal, or a metal of Group Ib, Group IIb, or Group IIIa of the periodic table, or a combination of two or more of these. Preferred examples of metals include lithium, sodium, magnesium, aluminum, zinc, and silver.

[0038] Alternatively, and also advantageously, the anode comprises or is substantially composed of an intercalation electrode. The intercalation electrode may be any electrode known in the art as suitable for the anode.

[0039] Alternatively, and also advantageously, the anode comprises or is substantially composed of a conversion electrode. The conversion electrode advantageously comprises an oxide, a nitride, a sulfide, or a combination of two or more of these.

[0040] Optionally, the battery cell may further comprise a high surface area substrate provided between the cathode, or separator if present, and the anode current collector or electronic conductor, or the anode if present. Advantageously, the high surface area substrate is provided such that, if present, at least a portion of the surface of the high surface area substrate contacts the surface of the anode current collector or electronic conductor, or, if present, at least a portion of the surface of the anode.

[0041] When a battery cell comprises a high surface area substrate and does not comprise an anode, the battery cell comprising the high surface area substrate advantageously comprises an electronic conductor.

[0042] When the battery cell comprises an electronic conductor, it may further comprise an anode lead extension. Advantageously, when the battery cell comprises an anode lead extension, at least a portion of the surface of the electronic conductor contacts at least a portion of the surface of the anode lead extension.

[0043] Advantageously, the electronic conductor comprises, where present, a metal, polymer, carbon, oxide, sulfide, nitride, carbide, silicide, or a combination of two or more of these, or is substantially composed thereof.

[0044] Advantageously, the battery cells according to the present invention are secondary batteries.

[0045] According to a second aspect of the present invention, a battery as set forth in the appended claims is provided. The battery comprises a stack of x battery cells according to a first aspect of the present invention, wherein x is between 2 and 20, preferably between 2 and 10, such as between 2 and 5. Effects of the invention

[0046] The advantages of the battery cells of the present invention include, but are not limited to, an improved lifespan. In particular, the battery cells of the present invention can be charged and discharged many times, thereby providing long lifespan characteristics. An additional advantage is that, compared to battery cells of the art, they have excellent conductivity and Coulombic efficiency without loss of metal. Brief explanation of the drawing

[0047] Now, embodiments of the present invention will be described in more detail with reference to the accompanying drawings, wherein the same reference numerals exemplify the same features and here: - FIG. 1 schematically illustrates an anode-free metal battery cell according to the present invention; - FIG. 2 schematically illustrates another anode-free metal battery cell according to the present invention; - FIG. 3 schematically illustrates an anode including a battery cell according to the present invention; - FIG. 4 schematically illustrates another anode including a battery cell according to the present invention; - FIG. 5 schematically illustrates another anode-free metal battery cell according to the present invention; - FIG. 6 schematically illustrates an additional anode-free metal battery cell according to the present invention; - FIG. 7 schematically illustrates another additional anode-free metal battery cell according to the present invention; - FIG. 8 shows the voltage of the anode-free battery cell of the present invention as a function of the specific charge per gram of the active material; - FIG. 9 shows the voltage of an anode including a battery cell of the present invention as a function of the charge-to-weight ratio per gram of an active material for repetitive charging and discharging of the battery cell; - FIG. 10 shows the charge-to-weight ratio per gram of the active material of two anodes comprising battery cells of the present invention as a function of the number of charge / discharge cycles; - FIG. 11 shows the charge-to-weight ratio per gram of the active material of two anodes including the battery cells of the present invention as a function of the number of charge / discharge cycles. - FIG. 12 shows the voltage of an anode including a battery cell of the present invention as a function of the charge-to-weight ratio per gram of the active material. Specific details for implementing the invention

[0048] FIG. 1 schematically illustrates a first embodiment of a battery cell (100) of the present invention. The battery cell (100) comprises a cathode current collector (1), a cathode (2), a solid electrolyte (3), and an anode current collector (4). The battery cell (100) does not include an anode, that is, the battery cell (100) is an anode-free metal battery cell. As is known in the art, during the first charging of the anode-free metal battery cell, a metal layer as an anode is formed in situ (deposited) on the anode current collector.

[0049] In the present invention, the terms anode-free metal battery cell and anode-free battery cell are used interchangeably. Advantageously, in an anode-free metal battery cell, "metal" refers to a metal present in the cathode, i.e., ions of the metal, i.e., metal ions, pass through the electrolyte for the in-situ deposition of an anode layer on the anode current collector.

[0050] Advantageously, the metal is an alkali metal, an alkaline earth metal, or a metal of 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.

[0051] Advantageously, the cathode current collector (1) is as described above. Advantageously, and as is known in the art, the cathode current collector (1) extends from the anode-free battery cell (100). In other words, the cathode current collector (1) advantageously has a portion extending from a stack comprising a cathode (2), an electrolyte (3), and an anode current collector (4). This can be realized by a method known in the art, for example, by providing a cathode current collector (1) having a surface area larger than that of the cathode (2). As is known, such an extension allows for easy connection or coupling of the cathode current collector (1) to an electronic circuit portion (not shown) to which the anode current collector (4) is advantageously also connected or coupled.

[0052] Advantageously, the cathode (2) is as described above. Advantageously, the active material comprises or is substantially composed of an alkali metal, an alkaline earth metal, or a metal of 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.

[0053] Alternatively or additionally and advantageously, the active material may comprise or substantially consist of an alkali metal-, alkaline earth metal-, or Group Ib, Group IIb, or Group IIIa metal-based intercalation compound. Non-limiting examples of intercalation compounds include lithium iron phosphate (LFP) and sodium iron phosphate (NFP). Non-limiting examples of active materials include 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).

[0054] Advantageously, the cathode comprises an active material in an amount between 25 wt% and 99.7 wt%, for example between 40 wt% and 99.5 wt%, preferably between 50 wt% and 99 wt%, for example between 60 wt% and 97.5 wt%, and more preferably between 75 wt% and 95 wt%, based on the total weight of the cathode.

[0055] Advantageously, the electrically conductive material comprises a carbon-containing material, such as carbon fibers, carbon nanotubes, carbon particulates (e.g., powder), or a combination of two or more of these. Advantageously, the electronically conductive material is a carbon-based electronically conductive material, such as graphite.

[0056] Advantageously, the cathode comprises an electrically conductive material in an amount between 0.1 wt% and 30 wt%, for example between 0.25 wt% and 25 wt%, preferably between 0.5 wt% and 20 wt%, for example between 1 wt% and 15 wt%, more preferably between 2 wt% and 10 wt%, based on the total weight of the electrode.

[0057] Advantageously, the binder comprises or substantially consists of rubbers such as styrene-butadiene rubber (SBR) or latex, polyvinylidene fluoride (PVDF), and polyvinylpyrrolidone (PVP), particularly high molecular weight PVP.

[0058] Advantageously, the cathode comprises a binder in an amount between 0.1 wt% and 30 wt% based on the total weight of the cathode, for example between 0.25 wt% and 25 wt%, preferably between 0.5 wt% and 20 wt%, for example between 0.75 wt% and 15 wt%, more preferably between 1 wt% and 10 wt%.

[0059] The solid electrolyte (3) is advantageously as described above, and is a non-aqueous solvent, an aluminum-based halide compound (AlX₃). n It includes ) and / or its polymeric form (where X is a halogen atom and n is between 1 and 6), metal salts of alkali metals, alkaline earth metals or metals of Group Ib, Group IIb or Group IIIa of the periodic table, and bis(fluorosulfonyl)imide (FSI) anions.

[0060] The metal or metals included in the active material of the cathode (2) and the metal or metals included in the SSE (3) as cations of the metal salt(s) may be the same or different. Advantageously, they are the same. For example, the battery cell may include lithium cobalt oxide (LiCoO2) as the active material of the cathode and LiFSI as the metal salt of the solid electrolyte, but is not limited thereto.

[0061] Advantageously, the anode current collector (4) comprises or is substantially made of at least one metal. Advantageously, the metal is copper, copper alloy, nickel, nickel alloy, steel, or lithium. The steel may be stainless steel or carbon steel, but is not limited thereto.

[0062] Advantageously, the anode current collector (4) extends from the anode-free battery cell (100). In other words, the anode current collector (4) advantageously has a portion extending from a stack comprising a cathode current collector (1), a cathode (2), and a solid electrolyte (3). This extension allows for easy connection or coupling of the anode current collector (4) to an electronic circuit portion (not shown) to which the cathode current collector (1) is also advantageously connected or coupled.

[0063] FIG. 2 schematically illustrates a second embodiment of a battery cell (101) of the present invention, which is an anode-free battery cell that does not include an anode. The anode-free metal battery cell (101) includes a cathode current collector (1). Advantageously, the cathode current collector (1) is as described above. The battery cell (101) further includes a cathode (2). Advantageously, the cathode (2) is as described above. The battery cell (101) further includes an anode current collector (4). The anode current collector (4) is advantageously as described above. The anode-free battery cell (101) also includes a solid electrolyte (3). The solid electrolyte (3) is as described above.

[0064] The anode-free metal battery cell (101) further comprises a separator (5). Advantageously, the separator (5) is as described above. Advantageously, the separator (5) is a separator membrane, i.e., a battery separator membrane. The separator (5) may be a porous separator membrane.

[0065] Advantageously, the separator (5) comprises one or more polymers or is substantially composed thereof. Advantageously, and alternatively or additionally, the battery separator (5) may be a ceramic material. For example, the separator (5) may comprise a ceramic-loaded polymer.

[0066] Non-limiting examples of suitable polymers include polypropylene (PP), polyethylene (PE), polytetrafluoroethylene (PTFE), and polyvinylidene difluoride (PVDF). PP, PE, PTFE, and PVDF are preferred materials due to their chemically inert properties. However, while they are not easily wetted, it is desirable that the porous separator can absorb liquid electrolytes. To this end, PP, PE, PTFE, and / or PVDF may be treated with a surface treatment or coating, such as spray coating, dip coating, or plasma coating—atmospheric pressure plasma or low-pressure plasma.

[0067] The separator (5) may include one layer or multiple layers. A multilayer separator of particular interest is a three-layer PVDF-PE-PVDF separator, which is optionally ceramic-loaded.

[0068] FIG. 3 schematically illustrates an additional battery cell (102) of the present invention. The battery cell (102) comprises a cathode current collector (1), which is advantageously as described above. The battery cell (102) further comprises a cathode (2), which is advantageously as described above. The battery cell (102) also comprises a solid electrolyte (3), which is advantageously as described above. The battery cell (102) also comprises an anode current collector (4). The anode current collector (4) is advantageously as described above.

[0069] The battery cell (102) further includes an anode (12), that is, the battery cell (102) is an anode that includes the battery cell. The anode (12) is advantageously as described above.

[0070] Advantageously, the anode comprises a metal layer or is substantially composed of a metal layer. The metal of the metal layer may be the same as or different from one of the metals included in the cathode, for example, in the active material of the cathode. Additionally, the metal(s) of the metal layer may be the same as or different from the metal of the metal salt(s) of the solid electrolyte. Advantageously, at least one metal of the metal layer is the same as the metal of the cathode. For example, when the cathode comprises lithium, the anode is advantageously a metal layer comprising or substantially composed of lithium.

[0071] Alternatively, and also advantageously, the anode comprises or substantially consists of an intercalation anode. Non-limiting examples of suitable intercalation electrodes are graphite and Li4Ti5O. 12 , or includes combinations thereof.

[0072] Alternatively, and also advantageously, the anode comprises or is substantially composed of a conversion electrode. Advantageously, the conversion electrode comprises or is substantially composed of an oxide, a nitride, a sulfide, or a combination of two or more of these. 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 (SnS₂). x It includes ) and vanadium sulfide (VS2 and VS4).

[0073] Advantageously, the anode may be provided by means known in the art, such as by providing a film, sheet, or foil, or by depositing a layer by known methods such as sputtering and plasma deposition.

[0074] FIG. 4 schematically illustrates another anode comprising a battery cell (103) of the present invention. The battery cell (103) comprises 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 of which are advantageously as described above.

[0075] FIG. 5 schematically illustrates a third embodiment of an anode-free metal battery cell (104) of the present invention. The anode-free metal battery cell (104) comprises a cathode current collector (1), a cathode (2), and a solid electrolyte (3), all of which are advantageously as described above. The battery cell (104) may further comprise a separator (not shown).

[0076] The battery cell (104) further includes an electronic conductor (10). The electronic conductor (10) is advantageously as described above. The electronic conductor (10) is advantageously functional as an anode current collector.

[0077] Advantageously, the electronic conductor (10) comprises or is substantially made 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 stainless steel or carbon steel, but is not limited thereto. For example, the electronic conductor may comprise a nickel-plated copper foil.

[0078] Alternatively, and alternatively or additionally, the electronic conductor (10) comprises or is substantially composed of a polymer. Preferred examples of polymers include, but are not limited to, poly(3,4-ethylenedioxythiophene) (PEDOT) and polyaniline.

[0079] Alternatively, and alternatively or additionally, the electronic conductor (10) comprises carbon or is substantially composed of it. Preferred examples of carbon include, but are not limited to, carbon black, carbon nanotubes, graphite, or a combination of two or more of these.

[0080] Alternatively, and alternatively or additionally, the electronic conductor (10) comprises or is substantially composed of one or more of oxides, sulfides, nitrides, carbides, or silicides.

[0081] The anode-free metal battery cell (104) further comprises a high surface area substrate (6). Advantageously, the high surface area substrate (6) is provided on the anode side of the battery cell (104). In other words, the high surface area substrate (6) is advantageously provided on the side of the electrolyte (3) opposite to the side of the cathode (2).

[0082] Advantageously, a high surface area substrate (6) is provided such that at least a portion of its (n external) surfaces (7) are in contact with at least a portion of the surface (8) of the electronic conductor (10). Advantageously, the surface (7) of the high surface area substrate (6) in contact with at least a portion of the electronic conductor (10) is different from the surface in contact with the SSE (3).

[0083] Advantageously, the high surface area substrate (6) has a porosity of at least 40%, wherein the porosity is measured by X-ray computed tomography. “At least 40% porosity” means, for the purposes of this disclosure, that the high surface area substrate (6) has a porosity of at least 40% at all locations or regions of the substrate (6).

[0084] Advantageously, the high surface area substrate (6) comprises or is substantially composed of an organic compound. Advantageously, the organic compound comprises or is substantially composed of a polymer, i.e., a polymer. Alternatively, and advantageously, the organic compound comprises or is substantially composed of a polymorph of carbon, i.e., a polymorph.

[0085] Advantageously, the polymer is selected from the group consisting of cellulose, regenerated cellulose (viscose), polypropylene, polyethylene, polyvinylidene difluoride, polytetrafluoroethylene, polyurethane, aramid, and silk. Additional examples of organic compounds include wool and polyaramide.

[0086] Non-limiting examples of carbon polymorphs include graphene, carbon nanotubes, graphite, hard carbon, and carbon black.

[0087] Advantageously, and additionally or alternatively, the high surface area substrate comprises or is substantially composed of an inorganic compound. Advantageously, the inorganic compound comprises or is substantially composed of lithium lanthanum zirconium oxide (LLZO) and / or a silica polymorph. Non-limiting examples of silica polymorphs include quartz, cristobalite, tridymite, coesite, stishovite, lechatelierite, and opal.

[0088] The high surface area substrate (6) may comprise a single layer or be composed of such a single layer, or may comprise multiple layers, i.e., two or more layers. When the high surface area substrate (6) comprises two or more layers, they may be identical or different. For example, they may have identical or different composition, structure, shape, thickness, or porosity. Advantageously, each layer has a porosity of at least 40%, wherein the porosity is measured by X-ray tomography.

[0089] The high surface area substrate (6) may have any shape, geometry, or structure that provides a substrate having a high surface area. Advantageously, the high surface area substrate (6) is a membrane, foam, nonwoven, woven textile, or knitted textile. Advantageously, the membrane and foam are disclosed cell membranes and foams.

[0090] FIG. 6 illustrates another anode-free metal battery cell (105) according to the present invention. The anode-free metal battery cell (105) comprises a cathode current collector (1), a cathode (2), a solid electrolyte (3), an electronic conductor (10), and a high surface area substrate (6), all of which are advantageously as described above with respect to FIG. 5.

[0091] The battery cell (105) further includes an anode lead extension (9). Advantageously, the anode lead extension (9) is advantageously extended from the anode-free battery cell (105) in the same manner as described above with respect to the anode current collector.

[0092] Advantageously, the anode lead extension (9) comprises or is substantially made of at least one metal. Advantageously, the metal is copper, a copper alloy, nickel, a nickel alloy, steel, or lithium. The steel may be stainless steel or carbon steel, but is not limited thereto.

[0093] Advantageously, at least a portion of the surface (8) of the electronic conductor (10) is in contact with at least a portion of the surface (7) of the high surface area substrate (6). Advantageously, the surface (7) of the high surface area substrate (6) in contact with the electronic conductor (10) at least partially is different from the surface of the high surface area substrate (6) in contact with the electrolyte (3).

[0094] Advantageously, at least a portion of the surface of the electronic conductor (10) also contacts at least a portion of the surface of the anode lead extension (9).

[0095] FIG. 7 illustrates another anode-free metal battery cell (106) according to the present invention. The anode-free metal battery cell (106) comprises a cathode current collector (1), a cathode (2), a solid electrolyte (3), a separator (5), a high surface area substrate (6), an anode lead extension (9), and an electronic conductor (10), all of which are advantageously as described above.

[0096] Examples

[0097] Example 1

[0098] 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 AlCl3, and 2.02 g of HFE as a surfactant to 20.25 g of DME as a non-aqueous solvent.

[0099] An anode-free battery cell is manufactured as a bi-stack pouch cell comprising two copper foils as anode current collectors sandwiching a cathode containing NCA as an active material. A three-layer ceramic-loaded separator comprising one layer of polyethylene sandwiched between two layers of polyvinylidene fluoride is provided between the cathode and the anode current collectors.

[0100] Then, the liquid precursor was provided into the anode-free battery cell and maintained at 60°C for 24 hours to convert the liquid precursor into a solid electrolyte. Based on the total weight of the SSE, the SSE contained 22.07 wt% LiFSI, 33.87 wt% LiTFSI, 5.23 wt% AlCl3, 3.53 wt% HFE, and 35.31 wt% DME.

[0101] Next, the battery cell operates galvanostatically at 5 mA (0.39 mA / cm² relative to the cathode surface). 2The cell was charged and discharged, and the cell potential was measured as a function of the charge-to-weight ratio per gram of the active material at room temperature. Figure 8 illustrates the results, where line 13 represents the charging curve and line 14 represents the discharging curve. From Figure 8, it is evident that 158 ​​mAh / g of the expected 170 mAh / g is available. In other words, only 12 mAh / g is lost during the initial in-situ lithium deposition.

[0102] Example 2

[0103] A liquid precursor was prepared by adding 16.00 g of LiFSI as a metal salt, 2.00 g of HFE as a surfactant, and 2.66 g of AlCl3 to 8.00 g of acetonitrile (ACN). Subsequently, the liquid precursor was maintained at a temperature of 20 ℃ for 24 hours to obtain a solid electrolyte (SSE).

[0104] 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 SSE.

[0105] A first battery cell (including an anode) was manufactured as a bistack pouch cell comprising aluminum foil (Al) as a cathode current collector sandwiched between two lithium iron phosphate (LFP) cathodes. Copper foil as an anode current collector, having a 50 μm thick lithium foil as an anode, was provided on each side of the LFP-Al-LFP compound. A three-layer ceramic-loaded separator comprising one layer of polyethylene sandwiched between two layers of polyvinylidene fluoride was provided between each of the anodes and cathodes (thus, a total of two separators were provided).

[0106] The anodes and cathodes were permeated with SSE by applying SSE onto the substrates of the anodes and cathodes with a spatula until the entire surface was uniformly covered with solid electrolyte.

[0107] After that, 10 charge / discharge cycles were performed on the first battery cell. Charging and discharging were performed at a constant current between 3.0 V and 3.8 V at a cathode surface of 0.25 mA / cm².

[0108] Figure 9 plots the voltage as a function of the charge-to-weight ratio per gram of the active material for charge / discharge cycles, where 15 represents the charge curves and 16 represents the discharge curves. It is evident that the charge and discharge are very stable during 10 cycles.

[0109] Example 3

[0110] A suspension was prepared by adding 10.02 g of LiFSI as a metal salt, 1.25 g of HFE as a surfactant, and 1.90 g of AlCl3 to 10.00 g of DME as a non-aqueous solvent.

[0111] Next, the suspension was heated at 60°C for 10 minutes to obtain a liquid precursor. Subsequently, the liquid precursor was maintained at a temperature of 20°C for 24 hours to obtain a solid electrolyte (SSE).

[0112] 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 SSE.

[0113] A second battery cell (including an anode) was manufactured as a bistack pouch cell comprising aluminum foil (Al) as a cathode current collector sandwiched between two lithium iron phosphate (LFP) cathodes. Copper foil as an anode current collector, having a 50 μm thick lithium foil as an anode, was provided on each side of the LFP-Al-LFP compound. A three-layer ceramic-loaded separator comprising one layer of polyethylene sandwiched between two layers of polyvinylidene fluoride was provided between each of the anodes and cathodes (thus, a total of two separators were provided).

[0114] The anodes and cathodes were permeated with SSE by applying SSE to the substrates of the anodes and cathodes with a spatula until the entire surface was uniformly covered with solid electrolyte.

[0115] After that, 20 charge / discharge cycles were performed on the first battery cell. Charging and discharging were performed at a constant current between 3.0 V and 3.8 V at a cathode surface of 0.25 mA / cm².

[0116] FIG. 10 illustrates the charge-to-weight ratio per gram of the active material of the first battery cell of Example 2 and the second battery cell of Example 3 as a function of the number of charge and discharge cycles. It is evident that the anodic capacity (17) for charging the (first) battery cell and the cathodic capacity (18) for discharging the (first) battery cell, for the first battery cell using ACN as a non-aqueous solvent, are very close to each other and remain substantially constant for at least 20 charge / discharge cycles. Although the anodic capacity (19) for charging the (second) battery cell and the cathodic capacity (20) for discharging the (second) battery cell, for the second battery cell using DME as a non-aqueous solvent, are slightly lower than those for the first battery cell, they also remain stable for each additional charge / discharge cycle up to at least 20 cycles.

[0117] Example 4

[0118] A liquid precursor was prepared by adding 10.00 g of LiFSI as a metal salt, 2.50 g of HFE as a surfactant, and 2.01 g of AlCl3 to 20.00 g of DME as a non-aqueous solvent.

[0119] A stacked anode comprising a 900 mAh battery cell having five layers of LFP-Al-LFP (i.e., aluminum foil (Al) as a cathode current collector sandwiched between two lithium iron phosphate (LFP) cathodes) was fabricated. A 13 µm thick copper foil as an anode current collector, having a 25 µm thick lithium foil as an anode, was provided on each side of the LFP-Al-LFP compound, thus providing six of these. A three-layer ceramic-loaded separator comprising one layer of polyethylene sandwiched between two layers of polyvinylidene fluoride was provided between each cathode and anode.

[0120] Then, the liquid precursor was supplied into the 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% AlCl3, 7.24 wt% HFE, and 57.95 wt% DME based on the total weight of the SSE.

[0121] Subsequently, the battery cell is electrostatically at 120 mA between 3.0 V and 3.8 V (0.25 mA / cm² relative to the cathode surface). 2 ) was charged and discharged.

[0122] FIG. 11 plots the charge-to-weight ratio per gram of the active material of a battery cell as a function of the number of charge and discharge cycles. It is evident that the anodic capacity (21) for charging the battery cell and the cathodic capacity (22) for discharging the battery cell are very close to each other and remain substantially constant for at least seven charge / discharge cycles. The difference between the anodic and cathodic capacities for the first cycle can be explained by the known fact that some of the first cycle capacity in an electrochemical system is irreversible.

[0123] Figure 12 plots the voltage of the battery cell as a function of the charge-to-weight ratio per gram of the active material for the first charge (line 23) and the subsequent discharge (line 24). The results clearly show the scaling-up potential of the solid-state battery cell. Explanation of the symbols

[0124] 1. Cathode entire house 2. Cathode 3. Solid electrolyte 4. Anode entire house 5. Separator 6. High surface area substrate 7. Surface of a high surface area substrate 8. Surface of the anode current collector 9. Anode Lead Extension 10. Electronic conductors 12. Anode 13. Charging curve of an anode-free battery cell 14. Discharge curve of an anode-free battery cell 15. Charge curves of a first anode including a battery cell 16. Discharge curves of the first anode including the battery cell 17. Anodic capacity of the first anode including the battery cell 18. Cathode capacity of the first anode including the battery cell 19. Anodic capacity of a second anode including a battery cell 20. Cathode capacity of a second anode including a battery cell 21. Anodic capacity of a stacked anode containing battery cells 22. Cathode capacity of a stacked anode containing battery cells 23. Charge curves of a stacked anode including battery cells 24. Discharge curves of a stacked anode containing battery cells 100. Anode-free metal battery cell 101. Anode-Free Metal Battery Cell 102. Anode containing a battery cell 103. Anode containing a battery cell 104. Anode-Free Metal Battery Cell 105. Anode-free metal battery cell 106. Anode-free metal battery cell

Claims

Claim 1 A battery cell selected from the group consisting of battery cells 100, 101, 102, 103, 104, 105, and 106, comprising a cathode current collector (1), a cathode (2), and a solid electrolyte (3), and further comprising an anode current collector (4) or an electronic conductor (10) functioning as an anode current collector, wherein the solid electrolyte (3) comprises a non-aqueous solvent, an aluminum-based halide compound AlX n As a polymer form of the aluminum-based halogenated compound AlX, wherein X is a halogen atom and n is between 1 and 6 n A battery cell characterized by comprising a polymer form, a metal salt of an alkali metal, an alkaline earth metal, or a Group Ib, Group IIb, or Group IIIa metal of the periodic table, and a bis(fluorosulfonyl)imide (FSI) anion. Claim 2 In claim 1, the battery cell, wherein the metal is lithium, sodium, magnesium, aluminum, zinc, or silver. Claim 3 A battery cell according to claim 1, wherein X is chlorine and n is 3, and the aluminum-based halide compound is AlCl3. Claim 4 A battery cell according to claim 1, wherein the metal salt comprises two or more types of anions, and one type of the anion of the metal salt is the FSI. Claim 5 A battery cell according to claim 4, further comprising at least one additional metal salt containing an anion, wherein the anion of the at least one additional metal salt is bis(trifluoromethane)sulfonimide (TFSI), dicyanamide (DCA), perchlorate (ClO4), difluorobis(oxalateto)borate (DFOB), or hexafluorophosphate (PF6). Claim 6 A battery cell according to claim 1, wherein the non-aqueous solvent is acetonitrile, dimethoxyethane, or an ionic liquid. Claim 7 A battery cell according to claim 1, wherein the non-aqueous solvent is an ionic liquid containing an anion, and the anion of the ionic liquid is the FSI. Claim 8 A battery cell according to claim 1, further comprising a separator (5) between the cathode (2) and the anode current collector (4) or between the cathode (2) and the electronic conductor (10), and selected from the group consisting of battery cells 101, 103 and 106. Claim 9 A battery cell selected from the group consisting of battery cells 102 and 103, comprising an anode current collector (4), further comprising an anode (12) between the solid electrolyte (3) and the anode current collector (4). Claim 10 In claim 9, the battery cell comprises an anode (12) comprising a metal layer comprising an alkali metal, an alkaline earth metal, or a metal of group Ib, group IIb, or group IIIa of the periodic table, or a combination of two or more of these. Claim 11 In claim 9, the anode (12) comprises an intercalation electrode or a conversion electrode, wherein the conversion electrode comprises an oxide, a nitride, a sulfide, or a combination of two or more of these, in a battery cell. Claim 12 A battery cell according to claim 1, further comprising a high surface area substrate (6) provided between the cathode (2) and the anode current collector (4) or between the cathode (2) and the electronic conductor (10), wherein at least a portion of the surface (7) of the high surface area substrate (6) is in contact with at least a portion of the surface of the anode current collector (4) or the electronic conductor (10), and selected from the group consisting of battery cells 104, 105 and 106. Claim 13 A battery cell according to claim 12, comprising an electronic conductor (10) and further comprising an anode lead extension (9), wherein at least a portion of the surface of the electronic conductor (10) is in contact with at least a portion of the surface of the anode lead extension (9), and selected from the group consisting of battery cells 105 and 106. Claim 14 In claim 1, the battery cell is a secondary battery cell. Claim 15 A battery comprising a stack of x battery cells according to claim 1, wherein x is between 2 and 20.

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