Acid treatment of solid electrolyte surfaces

Abstract

Acid treated solid electrolytes, methods of acid treating solid electrolyte thin films, and electrochemical devices including acid treated solid electrolyte thin films are described.

Description

[0001] This application claims priority and benefit to U.S. Provisional Patent Application No. 63 / 514,520, filed July 19, 2023, the entire contents of which are incorporated herein by reference for various purposes. Background Technology

[0002] Traditional rechargeable batteries use liquid electrolytes to physically separate the positive and negative electrodes (i.e., cathode and anode) for electrical insulation. However, liquid electrolytes present several problems, including flammability during thermal runaway, venting at high voltages, and chemical incompatibility with lithium metal anodes. As an alternative, solid-state electrolytes have been proposed as the next generation of rechargeable batteries. For example, the use of lithium-ion-conducting ceramic oxides such as lithium-filled garnet (e.g., Li7La3Zr2O) has been considered. 12 (Also known as LLZO) as an electrolyte membrane. See, for example, U.S. Patent Application Publication No. 2015 / 0099190, entitled “GARNETMATERIALS FOR LI SECONDARY BATTERIES AND METHODS OF MAKING AND USING GARNETMATERIALS”, published April 9, 2015 and filed October 7, 2014; U.S. Patent Nos. 8,658,317, 8,092,941, and 7,901,658; and U.S. Patent Application Publications Nos. 2011 / 0281175, 2013 / 0085055, 2014 / 0093785, and 2014 / 0170504, the entire contents of which are incorporated herein by reference for all purposes.

[0003] When LLZO is sintered and subsequently exposed to environmental conditions (room temperature, natural atmosphere, e.g., 78% N2 and 21% O2; and / or with simultaneous moisture), the surface of LLZO may become contaminated with surface materials, negatively impacting lithium-ion conductivity. For example, lithium carbonate (Li2CO3) can spontaneously form on the LLZO surface upon exposure to environmental conditions. (See Cheng, L., et al., "Interrelationships among Grain Size, Surface Composition, Air Stability, and Interfacial Resistance of Al-Substituted Li7La3Zr2O") 12Solid Electrolytes, “ACS Appl. Mater. Interfaces, 2015, 7 (32), pp 17649–17655” describes the mechanism of lithium carbonate formation in LLZO exposed to environmental conditions. This literature discloses that LLZO can form Li₂CO₃ through two pathways: the first involves reaction with moisture in the air to generate LiOH, which then reacts with CO₂ to form Li₂CO₃; the second involves a direct reaction between LLZO and CO₂. See also Cheng, L., et al., Phys. Chem. Chem. Phys., 2014, 16, 18294–18300, which discloses the formation of Li₂CO₃ on the surface of LLZO particles when exposed to air. Lithium carbonate and other forms of surface contamination (e.g., oxides, carbonates, or organic matter) can increase the interfacial impedance between the LLZO solid electrolyte and other electrochemical device components, thus negatively impacting the electrochemical performance of the solid electrolyte in the electrochemical device. Previous solutions included using annealing to remove surface substances that negatively impact electrochemical performance, such as those described in U.S. Patent No. 9,966,630 B2, entitled “ANNEALED GARNET ELECTROLYTE SEPARATORS,” issued May 8, 2018 (the entire contents of which are incorporated herein by reference for all purposes). PCT application WO 2019 / 090360, filed November 6, 2018, entitled “LITHIUM-STUFFED GARNET THIN FILMS AND PELLETS HAVING AN OXYFLUORINATED AND / OR FLUORINATED SURFACE AND METHODS OF MAKING AND USING THE THIN FILMS AND PELLETS” (the entire contents of which are incorporated herein by reference for all purposes), uses a solution comprising fluoride salts and solvents to remove surface substances. However, improvements are still needed.

[0004] Therefore, processes capable of reducing the interfacial resistance of LLZO thin-film solid electrolytes are needed. For example, processes are required to mitigate surface contaminants and to passivate the LLZO surface to prevent subsequent reactions with rechargeable battery components. Similarly, novel materials prepared using these processes are also needed. This application outlines solutions to these problems and other unmet needs in the related art. Invention Overview

[0005] In one aspect, this application describes a method for processing a bilayer comprising a metal foil or metal powder layer and a lithium-filled garnet layer, the method comprising: (a) providing a solution containing an acid source at a concentration of approximately 10 ppm to 5500 ppm; (b) contacting the bilayer with the solution for approximately one hour or less; and (c) removing the bilayer from the solution to obtain an acid-treated bilayer.

[0006] In a second aspect, this application describes a bilayer prepared by the method described in this application.

[0007] In a third aspect, this application describes a bilayer comprising a metal foil or metal powder layer and a lithium-filled garnet layer, the lithium-filled garnet layer containing members selected from the group consisting of phosphorus (P), titanium (Ti), chlorine (Cl), sulfur (S), boron (B), and zirconium (Zr), their ions, and combinations thereof, having a penetration depth of approximately 1 μm to 20 μm as measured by X-ray photoelectron spectroscopy (XPS).

[0008] In some embodiments, the bilayer contains members selected from the group consisting of phosphorus (P), titanium (Ti), chlorine (Cl), sulfur (S), boron (B), or zirconium (Zr), their ions, and combinations thereof, with a penetration depth of approximately 1 μm to 10 μm as measured by X-ray photoelectron spectroscopy. In some embodiments, the bilayer is characterized by having a layer of less than 1 μm containing lithium carbonate, lithium hydroxide, lithium oxide, their hydrates, their oxides, or combinations thereof. In some embodiments, the lithium carbonate atomic percentage content of the bilayer is approximately less than 1 but greater than 0, as measured by X-ray photoelectron spectroscopy (XPS). In some embodiments, the bilayer is a lithium-filled garnet film.

[0009] In some embodiments, the bilayer contains an acid, and / or its conjugate base, and / or its dissolved ions incorporated or bonded to the bilayer, wherein the acid, and / or its conjugate base, and / or its dissolved ions are selected from the group consisting of:

[0010] (a) H3PO4 and / or H2PO4 - and / or PO4 3- and / or PO4 2- ;

[0011] (b) H2SO4 and / or HSO4 - and / or SO4 2- and / or SO4 - ;

[0012] (c) HCl and / or Cl - ;

[0013] (d) H3BO3 and / or B(OH)4 - and / or BH2O3 - ;

[0014] (e) H2TiF6 and / or TiF6 2- ;

[0015] (f) H2ZrF6 and / or ZrF6 2- ;as well as

[0016] (g) Their combination.

[0017] In some embodiments, the bilayer contains H3PO4 and / or H2PO4. - and / or PO4 3- and / or PO4 2- In some embodiments, X-ray photoelectron spectroscopy measurements show that the bilayer contains phosphorus at a penetration depth of about 1 μm to 20 μm. In some embodiments, the bilayer includes a phosphorus-containing layer containing Li3PO4, LiH2PO4, or a combination thereof.

[0018] In some embodiments, the bilayer prepared by the method described in this application, or the bilayer described in this application (e.g., the sintered lithium-filled garnet film described in this application), is characterized by having an area resistivity (ASR) of approximately 50 Ω-cm at 25°C. 2 and 5 Ω-cm 2 Approximately 40 Ω-cm 2 and 5 Ω-cm 2 Approximately 35 Ω-cm 2 and 5 Ω-cm 2 Approximately 30 Ω-cm 2 and 5 Ω-cm 2 or about 20 Ω-cm 2 and 15 Ω-cm 2 In some embodiments, the ASR of acid-treated sintered lithium-filled garnet films can be maintained even when exposed to high temperature and high pressure (HTHV) conditions.

[0019] In a fourth aspect, this application describes an electrochemical battery or rechargeable battery comprising a bilayer prepared by the method described in this application or the bilayer described in this application. In some embodiments, the bilayer is sintered. In some embodiments, the bilayer is a lithium-filled garnet film. In some embodiments, the bilayer is a sintered lithium-filled garnet film.

[0020] In a fifth aspect, this application describes a continuous double-layer processing production line, comprising: a front roller wound with a double layer, the double layer comprising a metal foil or metal powder layer and a lithium-filled garnet layer; the metal layer being in contact with the front roller; a rear roller; and at least one acid treatment section between the front roller and the rear roller, comprising: a reservoir or dispensing unit; the reservoir or dispensing unit being suspended above the double layer; the reservoir or dispensing unit containing a solution containing an acid source with a concentration of approximately 10 ppm to 5500 ppm. Attached Figure Description

[0021] Figure 1 shows the area resistivity (ASR) of co-sintered (CSC) films after acid treatment with acid-selected H2TiF6, H3PO4 and H3BO3.

[0022] Figure 2 shows the ASR of CSC films treated with acid selected from H2TiF6, H3PO4 and H3BO3 after one month of HTHV testing at 60°C.

[0023] Figure 3 is the ASR diagram of the two layers after H3PO4 treatment.

[0024] Figure 4 shows the ASR diagram of the H3PO4-treated bilayer after one month of HTHV testing at 60°C.

[0025] Figure 5 shows the ASR diagrams of the bilayer after treatment with different concentrations of H3PO4.

[0026] Figure 6 shows the ASR diagram of bilayers treated with different concentrations of H3PO4 after HTHV testing at 60°C for one month. Detailed description

[0027] The following description is intended to enable those skilled in the art to make and use this application and incorporate it into a particular application. Various modifications and uses in different applications will be apparent to those skilled in the art, and the general principles defined herein can be applied to a wide range of embodiments. Therefore, this specification is not intended to limit the presented embodiments, but rather to embody the widest scope consistent with the principles and novel features disclosed herein.

[0028] All features disclosed in this specification (including any appended claims, abstract, and drawings) may be replaced by alternative features that serve the same, equivalent, or similar purpose, unless otherwise expressly stated. Therefore, unless otherwise expressly stated, each disclosed feature is merely one example of a series of equivalent or similar features.

[0029] Please note that the terms left, right, front, back, top, bottom, forward, reverse, clockwise, and counterclockwise are used for convenience only and do not describe any specific fixed direction. Rather, they are used to reflect the relative positions and / or orientations between parts of an object.

[0030] This application describes a simple, industrially scalable method using an aqueous acid solution under mild conditions, which enhances the interfacial properties of a bilayer comprising a metal foil or metal powder layer and a lithium-filled garnet layer. In some embodiments, the lithium-filled garnet layer is a lithium-filled garnet film. In some embodiments, the bilayer contains a minimum amount of lithium carbonate. In some embodiments, the lithium-filled garnet layer in the bilayer contains a minimum amount of lithium carbonate. The bilayer formed by the method described in this application (i.e., acid-treated or modified) has an acid-treated surface, and in some embodiments, the surface contains an acid, and / or its conjugate base, and / or its ions incorporated or bonded to the lithium-filled garnet layer.

[0031] Surprisingly, certain types of acidic solutions can etch away surface contaminants, such as Li₂CO₃, on bilayers (e.g., garnet-type solid electrolytes). For example, the resulting acid-treated garnet-type solid electrolytes maintain stable areal resistivity (ASR) even when exposed to high-temperature, high-pressure (HTHV) conditions. For example, in some embodiments, the ASR of the acid-treated garnet-type solid electrolyte increases by less than about 10% after HTHV testing, and this low ASR persists for at least about one week. In some embodiments, the ASR of the acid-treated garnet-type solid electrolyte increases by no more than about 10%, no more than about 15%, no more than about 20%, no more than about 30%, no more than about 40%, no more than about 50%, no more than about 60%, or no more than about 70% after HTHV testing. In some embodiments, the low ASR persists for at least about one week, at least about two weeks, at least about three weeks, at least about one month, at least about two months, at least about four months, at least about six months, at least about one year, or longer.

[0032] The methods described in this application include, but are not limited to: (1) a method for removing contaminants from a bilayer comprising a metal foil or metal powder layer and a lithium-filled garnet layer; (2) a method for providing a bilayer containing an acid and / or its conjugate base and / or its ions incorporated or bonded to said bilayer; and (3) a method for providing a bilayer characterized by measuring the percentage of lithium carbonate atoms as less than about 1 but greater than 0 by XPS. In one embodiment, the contaminant is lithium carbonate.

[0033] In some embodiments, the method described in this application not only removes contaminants from the bilayer but also provides a stable bilayer that can inhibit or slow down the formation rate of contaminants when the bilayer is exposed to environmental conditions, or even high temperature and high pressure conditions, thereby providing a bilayer capable of maintaining stable ASR.

[0034] definition

[0035] When the term "about" is used in this application to define a numerical value, such as about 15% w / w, it refers to the defined value and values ​​within a range of ±10% of that value. For example, about 15% w / w includes 15% w / w, as well as 13.5% w / w, 14% w / w, 14.5% w / w, 15.5% w / w, 16% w / w, or 16.5% w / w. For example, about 75°C includes 75°C, as well as 67°C, 68°C, 69°C, 70°C, 71°C, 72°C, 73°C, 74°C, 75°C, 76°C, 77°C, 78°C, 79°C, 80°C, 81°C, 82°C, or 83°C.

[0036] As used in this application, "ambient conditions" refers to room temperature and natural atmosphere, such as the Earth's atmosphere comprising approximately 78% N2 and 21% O2; and / or the simultaneous presence of moisture. Ambient conditions include standard temperature and pressure, and a relative humidity of at least 1%.

[0037] As used herein, the term "annealing" refers to the process of heating an electrolyte film from 200°C to 1000°C in a reducing atmosphere (such as, but not limited to, argon, hydrogen, or combinations thereof). An exemplary annealing process is described in U.S. Patent No. 9,966,630B2, issued May 8, 2018, entitled "ANNEALED GARNET ELECTROLYTE SEPARATORS," the entire contents of which are incorporated herein by reference for all purposes.

[0038] As used in this application, the term "selected from at least one member of the group" includes a single member of the group, multiple members of the group, or a combination of members of the group. Selecting at least one member of the group consisting of A, B, and C includes, for example, only A, only B, or only C, as well as A and B, A and C, B and C, and any combination of A, B, and C or A, B, and C.

[0039] As used in this application, the term "ASR" refers to area specific resistance. The term "lithium interfacial resistance" as used in this application refers to the interfacial resistance of a material to the insertion or conduction of Li⁺ ions. Lithium interfacial ASR (ASR)界面 ) through interface resistance (R 界面 According to the formula ASR 界面 = R 界面 * A / 2 is used for calculation, where A is the area of ​​the electrode in contact with the double layer, and the factor of 2 indicates that there are two interfaces (assuming the cell is symmetrical).

[0040] Unless otherwise stated, in this application, the areal resistivity (ASR) is measured by electrochemical cycling using an Arbin or Biologic instrument. ASR can be measured using electrochemical impedance spectroscopy (EIS). EIS can be performed on a Biologic VMP3 instrument or its equivalent. In the ASR measurement example, lithium contacts are deposited on both sides of the sample. An AC voltage of 25 mV rms is applied at a frequency ranging from 300 kHz to 0.1 mHz, while the current is measured simultaneously.

[0041] As used in this application, the term "bulk" refers to a portion of a material that extends at least 1 micrometer (μm) in space. Bulk refers to the portion of a material excluding its surface, as defined below. The bulk portion of a material with an acid-treated surface is the internal portion that has not undergone acid treatment. Whether a portion of a material has undergone acid treatment is determined by whether P, Ti, Cl, S, B, Zr, and / or F can be detected in that portion by XPS. The bulk phase of a material is also characterized as a portion not on the material surface and therefore not exposed to the material surface. The bulk portion of a bilayer (comprising a metal foil or metal powder layer and a lithium-filled garnet layer) can refer to the bulk portion of either layer of the bilayer (if no layer is specified).

[0042] As used in this application, the term "contaminant" refers to a chemical deviation from the original material. Contaminants in a bilayer include any material other than the bilayer itself, such as, but not limited to, lithium carbonate, lithium hydroxide, lithium oxide, lithium peroxide, their hydrates, their oxides, or combinations thereof, wherein the oxides and lithium oxides do not include lithium-filled garnet. Contaminants in a bilayer include, but are not limited to, hydroxides, peroxides, oxides, carbonates, and combinations thereof, which are not part of the bilayer.

[0043] As used in this application, the term "drying" refers to the process of evaporating a solvent or solution from a material, such as a bilayer or film. Drying can be passive, i.e., allowing the solvent or solution to evaporate, drying the bilayer or film at its storage location. Drying can be active, i.e., applying low-pressure compressed air to the bilayer or film to remove the solvent or solution. Active drying can also involve heating the bilayer or film to remove the solvent or solution. Drying, storage, and heating can be performed under ambient conditions. Drying, storage, and heating can be performed under drying chamber conditions. Drying, storage, and heating can be performed under glove box conditions.

[0044] As used in this application, the term "electrolyte" refers to a material that conducts ions while being electrically insulating. Electrolytes can be used as the positive and negative electrodes of electrically insulating rechargeable batteries, while allowing ions (e.g., Li⁺) to be conducted through them.

[0045] Unless otherwise stated, the terms "electrochemical cell" or "battery cell" as used herein refer to a single battery comprising a positive electrode and a negative electrode, which are ionically connected by an electrolyte. In some embodiments, a battery or module comprises multiple positive electrodes and / or multiple negative electrodes enclosed in a container, i.e., an electrochemical cell stack. Unless otherwise stated, a symmetrical cell is a battery having two lithium metal anodes separated by a solid electrolyte.

[0046] As used in this application, the term "electrochemical device" refers to an energy storage device, such as, but not limited to, devices that utilize electrochemical reactions (e.g., conversion chemical reactions, such as 3Li + FeF3). 3 LiF + Fe) Lithium secondary batteries that operate or generate electricity or current.

[0047] As used in this application, the term "film" (or "thin film") refers to a film with a thickness of less than 0.5 mm and greater than 10 nm. The film also has a lateral dimension greater than 5 mm. "Film" can be produced by continuous processes such as casting, plating, or screen printing.

[0048] As used in this application, "film thickness" refers to the median distance or measured distance between the top and bottom principal surfaces of a layer. In this application, the top and bottom principal surfaces refer to the surfaces of the layer with the largest geometrical surface area. In this application, the thickness is measured using a cross-sectional scanning electron microscope.

[0049] As used in this application, the term "high temperature and high voltage" refers to open-circuit storage of a finished battery at 100% state of charge and at a high temperature (above room temperature) for a desired period of time. The high temperature is at least 60°C, such as 60°C, 65°C, 70°C, 75°C, and 80°C. The high voltage is at least 4.0V, such as 4.0V, 4.1V, 4.2V, or 4.3V, where the voltage is relative to lithium (0V relative to lithium metal).

[0050] In some embodiments, the high temperature and high pressure test refers to maintaining at 45 °C or 60 °C for 4 V or higher (e.g., 4.0 V, 4.15 V, 4.25 V, or 4.35 V) for one week or one month.

[0051] As used herein, the term "lithium-stuffed garnet" refers to an oxide having a crystal structure related to the garnet crystal structure. Lithium-stuffed garnets include compounds conforming to the general formula Li A La B M' C M''Zr E O F or Li A La B M' C M'' D Nb E O F where 4 < A < 8.5, 1.5 < B < 4, 0 ≤ C ≤ 2, 0 ≤ D ≤ 2, 0 ≤ E ≤ 2, 10 < F < 13, and M' and M'' are each independently selected from Al, Mo, W, Nb, Sb, Ca, Ba, Sr, Ce, Hf, Rb, or Ta; or compounds conforming to the general formula Li a La b [[ID=二十九]]Zr c Al d M'' e O f where 5 < a < 7.7, 2 < b < 4, 0 ≤ c ≤ 2.5, 0 ≤ d ≤ 2, 0 ≤ e ≤ 2, 10 < f < 13, and M'' is a metal selected from Nb, Ta, V, W, Mo, Ga, or Sb. The garnets used in this application include the above garnets doped with Al or Al2O3. The garnets used in this application also include, but are not limited to, Li x La3Zr2O 12 + yAl2O3, where x can be from 5.8 to 7.0 and y can be 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 1.0. The garnets described in this application do not include YAG garnets (i.e., yttrium aluminum garnets, such as Y3Al5O 12 ). The garnets described in this application do not include silicate-based garnets, such as pyrope, almandine, spessartine, grossular, andradite, uvarovite, and the solid solution series of pyrope-almandine-spessartine and uvarovite-grossular-andradite. The garnets herein do not include the island silicate having the general formula X3Y2(SiO4)3, where X is Ca, Mg, Fe, and / or Mn; and Y is Al, Fe, and / or Cr.

[0052] The term "positive electrode" as used in this application refers to the positive ions (e.g., Li) in a secondary battery during battery discharge. ⁺ The electrode to which positive ions (e.g., Li) conduct. As used in this application, the term "negative electrode" refers to the electrode in a secondary battery that conducts positive ions (e.g., Li) during battery discharge. ⁺ It leaves from this electrode. In the process of forming a lithium metal electrode and a conversion chemical electrode (i.e., an active material such as NiF), x In a battery composed of lithium batteries, the electrode containing the chemical material used for conversion is called the positive electrode. In some common applications, the cathode is used instead of the positive electrode, and the anode is used instead of the negative electrode. When a lithium secondary battery is charged, lithium ions migrate from the positive electrode (e.g., NiF) to the positive electrode. x Lithium ions conduct from the negative electrode (e.g., lithium metal, i.e., the anode) to the positive electrode (e.g., NiF₂) during discharge. x (i.e., cathode) conduction.

[0053] As used in this application, the term "separator" refers to a solid electrolyte that conducts Li ions, is essentially an insulator of electrons, and is suitable as a physical barrier or spacer between the positive and negative electrodes in an electrochemical or rechargeable battery. In this application, the lithium-ion conductivity of the separator is at least 10 times the electronic conductivity of the separator. 3 Times (usually 10) 6 When the lithium content is increased (by a factor of 1), the membrane is substantially insulating to electrons. Unless explicitly stated otherwise, the membrane used in this application is stable in contact with lithium metal. In one embodiment, the membrane is a thin-film garnet membrane, for example, a lithium-filled garnet film. In another embodiment, the membrane is a bare film, a CSC film, or a film-on-foil (e.g., a bilayer comprising a metal foil or metal powder layer and a lithium-filled garnet layer).

[0054] As used in this application, the term "surface" refers to a material or portion of material located near or at the interface between two phases, two chemical substances, or two states of matter. A surface is a region of contact between two phases or states of matter (e.g., solid-gas, liquid-gas, or solid-liquid). For example, the interface between two directly contacting solids is a surface. For example, a bilayer exposed to air (including, but not limited to, a thin-film garnet bilayer) has a surface formed by the outer periphery or outer portion of the bilayer in contact with air. For a rectangular bilayer, there is a top surface and a bottom surface, each with a geometrical surface area greater than the surface area of ​​any one of the four sides. In this example of a rectangular bilayer, there are four sides, each with a geometrical surface area smaller than the top or bottom surface. For a disk-shaped bilayer, there is a top surface and a bottom surface, both with geometrical surface areas greater than the circumferential side surface of the disk-shaped bilayer. The geometrical surface area for a square or rectangular surface is calculated by multiplying the length of the surface by its width. For a disk-shaped surface, the geometrical surface area is calculated by multiplying π by the square of the disk radius, i.e., πr², where r is the radius of the disk surface. The geometric surface area of ​​the disk's lateral surface is calculated by multiplying the disk's circumference by the width of its lateral surface. When used as an electrolyte in an electrochemical cell, the top or bottom surface is the surface of the bilayer that directly contacts the negative electrode (e.g., lithium metal), the positive electrode (i.e., the cathode or cathode electrolyte in the positive electrode), and / or the layer or binder disposed between the bilayer and the positive electrode. The surface is defined by a region that is larger or more extended in physical dimensions along the x and y axes than in physical dimensions along the z axis, where the z axis is perpendicular to the surface. The depth, roughness, or thickness of the surface can be on the molecular weight scale (0.1 nanometers to 10 nanometers) or up to 1, 2, 3, 4, or 5 micrometers.

[0055] As used in this application, the term "XPS" refers to X-ray photoelectron spectroscopy: a surface-sensitive quantitative spectroscopic technique capable of measuring elemental composition within a range of one part per thousand. XPS can be used to determine the empirical formula of an analyte. XPS can also be used to determine the chemical and electronic states of elements present in a material.

[0056] The term "LLZO" as used in this application refers to lithium lanthanum zirconium oxide, which, when crystallized into garnet crystals, is called lithium-filled garnet as defined above.

[0057] As used in this application, the term "ESS" refers to a mixture of vinyl sulfite (ES) and sulfolane. Sulfolane refers to tetrahydrothiophene-1,1-dioxide, which has the following cyclic sulfone structure:

[0058]

[0059] Unless otherwise stated, the ratio of ES:sulfolane is calculated on a volume ratio (v / v). Acid treatment method for lithium-filled garnet electrolyte

[0060] In one aspect, this application describes a method for processing a bilayer comprising a metal foil or metal powder layer and a lithium-filled garnet layer, the method comprising: (a) providing a solution containing an acid source at a concentration of about 10 ppm to 5500 ppm; (b) contacting the bilayer with the solution for about one hour or less; and (c) removing the bilayer from the solution to obtain an acid-treated bilayer.

[0061] In some embodiments, the double-layered metal foil comprises pure nickel. In some embodiments, the double-layered metal foil comprises a nickel alloy. In some embodiments, the nickel alloy comprises nickel and iron. In some embodiments, the nickel alloy has a nickel-iron ratio of 85:15.

[0062] In some embodiments, the bilayer is sintered. In some embodiments, the bilayer comprises a sintered lithium-filled garnet layer.

[0063] In some embodiments, including any of the foregoing embodiments, the acid source contains an acid, and / or its conjugate base, and / or its dissolved ions, selected from the group consisting of:

[0064] (a) H3PO4 and / or H2PO4 - and / or PO4 3- and / or PO4 2- ;

[0065] (b) H2SO4 and / or HSO4 - and / or SO4 2- and / or SO4 - ;

[0066] (c) HCl and / or Cl - ;

[0067] (d) H3BO3 and / or B(OH)4 - and / or BH2O3 - ;

[0068] (e) H2TiF6 and / or TiF6 2- ;

[0069] (f) H2ZrF6 and / or ZrF6 2- ;as well as

[0070] (g) Their combination.

[0071] In one embodiment, including any of the foregoing embodiments, the acid source also contains water.

[0072] In one embodiment, including any of the foregoing embodiments, the acid source contains H3PO4 and / or H2PO4.- and / or PO4 3- and / or PO4 2- In one embodiment, including any of the foregoing embodiments, the acid source contains H3PO4 and / or H2PO4 in an aqueous solution. - and / or PO4 3- and / or PO4 2- In one embodiment, including any of the foregoing embodiments, the acid source contains H3PO4 and / or H2PO4 in an aqueous solution. - and / or PO4 3- and / or PO4 2- The concentration was approximately 85 wt%.

[0073] In one embodiment, including any of the foregoing embodiments, the acid source contains H2TiF6 and / or TiF6. 2- In one embodiment, including any of the foregoing embodiments, the acid source contains H₂TiF₆ and / or TiF₆ in an aqueous solution. 2- .

[0074] In one embodiment, including any of the foregoing embodiments, the acid source contains HCl and / or Cl. - In one embodiment, including any of the foregoing embodiments, the acid source contains HCl and / or Cl in an aqueous solution. - .

[0075] In one embodiment, including any of the foregoing embodiments, the acid source contains H2SO4 and / or HSO4. - and / or SO4 2- and / or SO4 - In one embodiment, including any of the foregoing embodiments, the acid source contains H2SO4 and / or HSO4 in an aqueous solution. - and / or SO4 2- and / or SO4 - .

[0076] In one embodiment, including any of the foregoing embodiments, the acid source contains H3BO3 and / or B(OH)4. - and / or BH2O3 - In one embodiment, including any of the foregoing embodiments, the acid source contains H3BO3 and / or B(OH)4 in an aqueous solution. - and / or BH2O3 - .

[0077] In one embodiment, including any of the foregoing embodiments, the acid source contains H2ZrF6 and / or ZrF6. 2-In one embodiment, including any of the foregoing embodiments, the acid source contains H2ZrF6 and / or ZrF6 in an aqueous solution. 2- .

[0078] In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is approximately 0.001% (w / v) to 0.1% (w / v). In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is approximately 0.003% (w / v) to 0.03% (w / v). In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is approximately 0.005% (w / v) to 0.05% (w / v). In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is approximately 0.008% (w / v) to 0.08% (w / v).

[0079] In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is about 0.001% (w / v), about 0.002% (w / v), about 0.003% (w / v), about 0.004% (w / v), about 0.005% (w / v), about 0.006% (w / v), about 0.007% (w / v), about 0.008% (w / v), about 0.009% (w / v), about 0.01% (w / v), about 0.02% (w / v), about 0.03% (w / v), about 0.04% (w / v), about 0.05% (w / v), about 0.06% (w / v), about 0.07% (w / v), about 0.08% (w / v), about 0.09% (w / v), or about 0.1% (w / v).

[0080] In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is about 0.001% (w / v) to 0.0025% (w / v), about 0.002% (w / v) to 0.004% (w / v), about 0.003% (w / v) to 0.005% (w / v), about 0.004% (w / v) to 0.006% (w / v), or about 0.0045% (w / v) to 0.0065% (w / v).

[0081] In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is about 0.03% (w / v) to 0.04% (w / v), about 0.035% (w / v) to 0.045% (w / v), about 0.04% (w / v) to 0.05% (w / v), about 0.045% (w / v) to 0.055% (w / v), or about 0.045% (w / v) to 0.06% (w / v).

[0082] In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is approximately 0.001% (w / v). In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is approximately 0.0025% (w / v). In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is approximately 0.003% (w / v). In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is approximately 0.005% (w / v). In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is approximately 0.008% (w / v). In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is approximately 0.025% (w / v). In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is approximately 0.03% (w / v). In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is approximately 0.05% (w / v). In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is approximately 0.08% (w / v).

[0083] In some embodiments, the concentration of the acid source in the solution is about 10 ppm to about 5500 ppm.

[0084] In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is about 10 ppm to about 1000 ppm, about 100 ppm to about 800 ppm, about 250 ppm to about 750 ppm, or about 400 ppm to about 600 ppm.

[0085] In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is about 10 ppm to 50 ppm, about 50 ppm to 100 ppm, about 100 ppm to 300 ppm, about 300 ppm to 500 ppm, about 500 ppm to 700 ppm, or about 700 ppm to 1000 ppm.

[0086] In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is about 10 ppm to 25 ppm, about 20 ppm to 40 ppm, about 30 ppm to 50 ppm, about 40 ppm to 60 ppm, or about 45 ppm to 65 ppm. In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is about 300 ppm to 400 ppm, about 350 ppm to 450 ppm, about 400 ppm to 500 ppm, about 450 ppm to 550 ppm, or about 450 ppm to 600 ppm. In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is about 1000 ppm to 5500 ppm, about 2000 ppm to 5500 ppm, about 3000 ppm to 5500 ppm, or about 4000 ppm to 5500 ppm. In some embodiments, the concentration of the acid source in the solution is about 1000 ppm to 2000 ppm, about 1500 ppm to 2500 ppm, about 2000 ppm to 3000 ppm, about 2500 ppm to 3500 ppm, about 3000 ppm to 4000 ppm, about 3500 ppm to 4500 ppm, about 4000 to 5000 ppm, or about 4500 ppm to 5500 ppm.

[0087] In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is approximately 10 ppm. In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is approximately 50 ppm. In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is approximately 60 ppm. In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is approximately 75 ppm. In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is approximately 100 ppm. In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is approximately 150 ppm. In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is approximately 200 ppm. In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is approximately 300 ppm. In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is approximately 400 ppm. In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is approximately 450 ppm. In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is approximately 500 ppm. In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is approximately 550 ppm. In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is approximately 600 ppm. In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is approximately 650 ppm. In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is approximately 700 ppm. In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is approximately 800 ppm. In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is approximately 900 ppm.

[0088] In some embodiments, the concentration of the acid source in the solution is approximately 1000 ppm to 5000 ppm.

[0089] In one embodiment, including any of the foregoing embodiments, the solution contains an acid source selected from the group consisting of H3PO4, H2TiF6, HCl, H2SO4, H3BO3, H2ZrF6, and combinations thereof, wherein the concentration of the acid source in the acidic solution is approximately 0.001% (w / v), approximately 0.002% (w / v), approximately 0.003% (w / v), approximately 0.004% (w / v), approximately 0.005% (w / v), approximately 0.006% (w / v), approximately 0.007% (w / v), approximately 0.008% (w / v), approximately 0.009% (w / v), approximately 0.01% (w / v), approximately 0.02% (w / v), approximately 0.03% (w / v), approximately 0.04% (w / v), approximately 0.05% (w / v), approximately 0.06% (w / v), or approximately 0.07%. (w / v), about 0.08% (w / v), about 0.09% (w / v) or about 0.1% (w / v).

[0090] In one embodiment, including any of the foregoing embodiments, the solution contains an acid source comprising members selected from the group consisting of H3PO4, H2TiF6, HCl, H2SO4, H3BO3, H2ZrF6, and combinations thereof, wherein the concentration of the acid source in the acidic solution is about 0.001% (w / v) to 0.0025% (w / v), about 0.002% (w / v) to 0.004% (w / v), about 0.003% (w / v) to 0.005% (w / v), about 0.004% (w / v) to 0.006% (w / v), or about 0.0045% (w / v) to 0.0065% (w / v). In one embodiment, including any of the foregoing embodiments, the solution contains an acid source comprising a member selected from the group consisting of H3PO4, H2TiF6, HCl, H2SO4, H3BO3, H2ZrF6, and combinations thereof, wherein the concentration of the acid source in the acidic solution is about 0.03% (w / v) to 0.04% (w / v), about 0.035% (w / v) to 0.045% (w / v), about 0.04% (w / v) to 0.05% (w / v), about 0.045% (w / v) to 0.055% (w / v), or about 0.045% (w / v) to 0.06% (w / v). In one embodiment, including any of the foregoing embodiments, the solution contains an acid source selected from the group consisting of H3PO4, H2TiF6, HCl, H2SO4, H3BO3, H2ZrF6, and combinations thereof, wherein the concentration of the acid source in the acidic solution is about 10 ppm to 25 ppm, about 20 ppm to 40 ppm, about 30 ppm to 50 ppm, about 40 ppm to 60 ppm, or about 45 ppm to 65 ppm. In one embodiment, including any of the foregoing embodiments, the solution contains an acid source selected from the group consisting of H3PO4, H2TiF6, HCl, H2SO4, H3BO3, H2ZrF6, and combinations thereof, wherein the concentration of the acid source in the acidic solution is about 300 ppm to 400 ppm, about 350 ppm to 450 ppm, about 400 ppm to 500 ppm, about 450 ppm to 550 ppm, or about 450 ppm to 600 ppm.In one embodiment, including any of the foregoing embodiments, the solution contains an acid source comprising members selected from the group consisting of H3PO4, H2TiF6, HCl, H2SO4, H3BO3, H2ZrF6, and combinations thereof, wherein the concentration of the acid source in the acidic solution is approximately 1000 ppm to 2000 ppm, approximately 1500 ppm to 2500 ppm, approximately 2000 ppm to 3000 ppm, approximately 2500 ppm to 3500 ppm, approximately 3000 ppm to 4000 ppm, approximately 3500 ppm to 4500 ppm, approximately 4000 to 5000 ppm, or approximately 4500 ppm to 5500 ppm.

[0091] In one embodiment, including any of the foregoing embodiments, the acid source contains H3PO4 and / or H2PO4. - and / or PO4 3- and / or PO4 2- The concentration of the acid source in the solution is approximately 0.001% (w / v), approximately 0.002% (w / v), approximately 0.003% (w / v), approximately 0.004% (w / v), approximately 0.005% (w / v), approximately 0.006% (w / v), approximately 0.007% (w / v), approximately 0.008% (w / v), approximately 0.009% (w / v), approximately 0.01% (w / v), approximately 0.02% (w / v), approximately 0.03% (w / v), approximately 0.04% (w / v), approximately 0.05% (w / v), approximately 0.06% (w / v), approximately 0.07% (w / v), approximately 0.08% (w / v), approximately 0.09% (w / v), or approximately 0.1% (w / v). In one embodiment, including any of the foregoing embodiments, the acid source contains H3PO4 and / or H2PO4. - and / or PO4 3- and / or PO4 2- The concentration of the acid source in the solution is approximately 0.001% (w / v) to 0.0025% (w / v), approximately 0.002% (w / v) to 0.004% (w / v), approximately 0.003% (w / v) to 0.005% (w / v), approximately 0.004% (w / v) to 0.006% (w / v), or approximately 0.0045% (w / v) to 0.0065% (w / v). In one embodiment, including any of the foregoing embodiments, the acid source contains H3PO4 and / or H2PO4. - and / or PO4 3- and / or PO4 2-The concentration of the acid source in the solution is about 0.03% (w / v) to 0.04% (w / v), about 0.035% (w / v) to 0.045% (w / v), about 0.04% (w / v) to 0.05% (w / v), about 0.045% (w / v) to 0.055% (w / v), or about 0.045% (w / v) to 0.06% (w / v).

[0092] In one embodiment, including any of the foregoing embodiments, the acid source contains H3PO4 and / or H2PO4. - and / or PO4 3- and / or PO4 2- The concentration of the acid source in the solution is approximately 10 ppm to 25 ppm, approximately 20 ppm to 40 ppm, approximately 30 ppm to 50 ppm, approximately 40 ppm to 60 ppm, or approximately 45 ppm to 65 ppm. In one embodiment, including any of the foregoing embodiments, the acid source contains H3PO4 and / or H2PO4. - and / or PO4 3- and / or PO4 2- The concentration of the acid source in the solution is approximately 300 ppm to 400 ppm, approximately 350 ppm to 450 ppm, approximately 400 ppm to 500 ppm, approximately 450 ppm to 550 ppm, or approximately 450 ppm to 600 ppm. In one embodiment, including any of the foregoing embodiments, the acid source contains H3PO4 and / or H2PO4. - and / or PO4 3- and / or PO4 2- The concentration of the acid source in the solution is approximately 1000 ppm to 5500 ppm, approximately 2000 ppm to 5500 ppm, approximately 3000 ppm to 5500 ppm, or approximately 4000 ppm to 5500 ppm. In one embodiment, including any of the foregoing embodiments, the acid source contains H3PO4 and / or H2PO4. - and / or PO4 3- and / or PO4 2- The concentration of the acid source in the solution is approximately 1000 ppm to 2000 ppm, approximately 1500 ppm to 2500 ppm, approximately 2000 ppm to 3000 ppm, approximately 2500 ppm to 3500 ppm, approximately 3000 ppm to 4000 ppm, approximately 3500 ppm to 4500 ppm, approximately 4000 to 5000 ppm, and approximately 4500 ppm to 5500 ppm.

[0093] In one embodiment, including any of the foregoing embodiments, the acid source contains H3PO4 and / or H2PO4. - and / or PO4 3- and / or PO4 2- The concentration of the acid source in the solution is approximately 50 ppm. In one embodiment, including any of the foregoing embodiments, the acid source contains H3PO4 and / or H2PO4. - and / or PO4 3- and / or PO4 2- The concentration of the acid source in the solution is approximately 500 ppm. In one embodiment, including any of the foregoing embodiments, the acid source contains H3PO4 and / or H2PO4. - and / or PO4 3- and / or PO4 2- The concentration of the acid source in the solution is approximately 5000 ppm. In one embodiment, including any of the foregoing embodiments, the acid source contains H3PO4 and / or H2PO4. - and / or PO4 3- and / or PO4 2- The concentration of the acid source in the solution is approximately 5500 ppm.

[0094] In one embodiment, including any of the foregoing embodiments, the acid source further contains water. For example, in one embodiment, including any of the foregoing embodiments, the acid source contains (1) H3PO4 and / or H2PO4. - and / or PO4 3- and / or PO4 2- (2) Water, wherein the concentration of the acid source in the solution is about 10 ppm to 25 ppm, about 20 ppm to 40 ppm, about 30 ppm to 50 ppm, about 40 ppm to 60 ppm, or about 45 ppm to 65 ppm. In further embodiments, including any of the foregoing embodiments, the acid source contains (1) H3PO4 and / or H2PO4. - and / or PO4 3- and / or PO4 2- (2) Water, wherein the concentration of the acid source in the solution is approximately 50 ppm.

[0095] In one embodiment, including any of the foregoing embodiments, the acid source contains H2TiF6 and / or TiF6. 2-The concentration of the acid source in the solution is about 0.001% (w / v) to 0.0025% (w / v), about 0.002% (w / v) to 0.004% (w / v), about 0.003% (w / v) to 0.005% (w / v), about 0.004% (w / v) to 0.006% (w / v), or about 0.0045% (w / v) to 0.0065% (w / v).

[0096] In one embodiment, including any of the foregoing embodiments, the acid source contains H2TiF6 and / or TiF6. 2- The concentration of the acid source in the solution is about 0.03% (w / v) to 0.04% (w / v), about 0.035% (w / v) to 0.045% (w / v), about 0.04% (w / v) to 0.05% (w / v), about 0.045% (w / v) to 0.055% (w / v), or about 0.045% (w / v) to 0.06% (w / v).

[0097] In one embodiment, including any of the foregoing embodiments, the acid source contains H2TiF6 and / or TiF6. 2- The concentration of the acid source in the solution is approximately 10 ppm to 25 ppm, approximately 20 ppm to 40 ppm, approximately 30 ppm to 50 ppm, approximately 40 ppm to 60 ppm, or approximately 45 ppm to 65 ppm.

[0098] In one embodiment, including any of the foregoing embodiments, the acid source contains H2TiF6 and / or TiF6. 2- The concentration of the acid source in the solution is approximately 300 ppm to 400 ppm, approximately 350 ppm to 450 ppm, approximately 400 ppm to 500 ppm, approximately 450 ppm to 550 ppm, or approximately 450 ppm to 600 ppm. In one embodiment, including any of the foregoing embodiments, the acid source contains H2TiF6 and / or TiF6. 2- The concentration of the acid source in the solution is approximately 1000 ppm to 5500 ppm, approximately 2000 ppm to 5500 ppm, approximately 3000 ppm to 5500 ppm, or approximately 4000 ppm to 5500 ppm. In one embodiment, including any of the foregoing embodiments, the acid source contains H2TiF6 and / or TiF6. 2-The concentration of the acid source in the solution is approximately 1000 ppm to 2000 ppm, approximately 1500 ppm to 2500 ppm, approximately 2000 ppm to 3000 ppm, approximately 2500 ppm to 3500 ppm, approximately 3000 ppm to 4000 ppm, approximately 3500 ppm to 4500 ppm, approximately 4000 ppm to 5000 ppm, and approximately 4500 ppm to 5500 ppm.

[0099] In one embodiment, including any of the foregoing embodiments, the acid source contains HCl and / or Cl. - The concentration of the acid source in the solution is about 0.001% (w / v) to 0.0025% (w / v), about 0.002% (w / v) to 0.004% (w / v), about 0.003% (w / v) to 0.005% (w / v), about 0.004% (w / v) to 0.006% (w / v), or about 0.0045% (w / v) to 0.0065% (w / v).

[0100] In one embodiment, including any of the foregoing embodiments, the acid source contains HCl and / or Cl. - The concentration of the acid source in the solution is about 0.03% (w / v) to 0.04% (w / v), about 0.035% (w / v) to 0.045% (w / v), about 0.04% (w / v) to 0.05% (w / v), about 0.045% (w / v) to 0.055% (w / v), or about 0.045% (w / v) to 0.06% (w / v).

[0101] In one embodiment, including any of the foregoing embodiments, the acid source contains HCl and / or Cl. - The concentration of the acid source in the solution is approximately 10 ppm to 25 ppm, approximately 20 ppm to 40 ppm, approximately 30 ppm to 50 ppm, approximately 40 ppm to 60 ppm, or approximately 45 ppm to 65 ppm.

[0102] In one embodiment, including any of the foregoing embodiments, the acid source contains HCl and / or Cl. - The concentration of the acid source in the solution is approximately 300 ppm to 400 ppm, approximately 350 ppm to 450 ppm, approximately 400 ppm to 500 ppm, approximately 450 ppm to 550 ppm, or approximately 450 ppm to 600 ppm.

[0103] In one embodiment, including any of the foregoing embodiments, the acid source contains HCl and / or Cl. - The concentration of the acid source in the solution is approximately 1000 ppm to 5500 ppm, approximately 2000 ppm to 5500 ppm, approximately 3000 ppm to 5500 ppm, or approximately 4000 ppm to 5500 ppm.

[0104] In one embodiment, including any of the foregoing embodiments, the acid source contains H2SO4 and / or HSO4. - and / or SO4 2- and / or SO4 - The concentration of the acid source in the solution is approximately 0.001% (w / v) to 0.0025% (w / v), approximately 0.002% (w / v) to 0.004% (w / v), approximately 0.003% (w / v) to 0.005% (w / v), approximately 0.004% (w / v) to 0.006% (w / v), or approximately 0.0045% (w / v) to 0.0065% (w / v). In one embodiment, including any of the foregoing embodiments, the acid source contains H2SO4 and / or HSO4. - and / or SO4 2- and / or SO4 - The concentration of the acid source in the solution is about 0.03% (w / v) to 0.04% (w / v), about 0.035% (w / v) to 0.045% (w / v), about 0.04% (w / v) to 0.05% (w / v), about 0.045% (w / v) to 0.055% (w / v), or about 0.045% (w / v) to 0.06% (w / v).

[0105] In one embodiment, including any of the foregoing embodiments, the acid source contains H2SO4 and / or HSO4. - and / or SO4 2- and / or SO4 - The concentration of the acid source in the solution is approximately 10 ppm to 25 ppm, approximately 20 ppm to 40 ppm, approximately 30 ppm to 50 ppm, approximately 40 ppm to 60 ppm, or approximately 45 ppm to 65 ppm. In one embodiment, including any of the foregoing embodiments, the acid source contains H2SO4 and / or HSO4. - and / or SO4 2- and / or SO4 -The concentration of the acid source in the solution is approximately 300 ppm to 400 ppm, approximately 350 ppm to 450 ppm, approximately 400 ppm to 500 ppm, approximately 450 ppm to 550 ppm, or approximately 450 ppm to 600 ppm. In one embodiment, including any of the foregoing embodiments, the acid source contains H2SO4 and / or HSO4. - and / or SO4 2- and / or SO4 - The concentration of the acid source in the solution is approximately 1000 ppm to 5500 ppm, approximately 2000 ppm to 5500 ppm, approximately 3000 ppm to 5500 ppm, or approximately 4000 ppm to 5500 ppm. In one embodiment, including any of the foregoing embodiments, the acid source contains H3BO3 and / or B(OH)4. - and / or BH2O3 - The concentration of the acid source in the solution is approximately 0.001% (w / v) to 0.0025% (w / v), approximately 0.002% (w / v) to 0.004% (w / v), approximately 0.003% (w / v) to 0.005% (w / v), approximately 0.004% (w / v) to 0.006% (w / v), or approximately 0.0045% (w / v) to 0.0065% (w / v). In one embodiment, including any of the foregoing embodiments, the acid source contains H3BO3 and / or B(OH)4. - and / or BH2O3 - The concentration of the acid source in the solution is about 0.03% (w / v) to 0.04% (w / v), about 0.035% (w / v) to 0.045% (w / v), about 0.04% (w / v) to 0.05% (w / v), about 0.045% (w / v) to 0.055% (w / v), or about 0.045% (w / v) to 0.06% (w / v).

[0106] In one embodiment, including any of the foregoing embodiments, the acid source contains H3BO3 and / or B(OH)4. - and / or BH2O3 - The concentration of the acid source in the solution is approximately 10 ppm to 25 ppm, approximately 20 ppm to 40 ppm, approximately 30 ppm to 50 ppm, approximately 40 ppm to 60 ppm, or approximately 45 ppm to 65 ppm. In one embodiment, including any of the foregoing embodiments, the acid source contains H3BO3 and / or B(OH)4. - and / or BH2O3 -The concentration of the acid source in the solution is approximately 1000 ppm to 2000 ppm, approximately 1500 ppm to 2500 ppm, approximately 2000 ppm to 3000 ppm, approximately 2500 ppm to 3500 ppm, approximately 3000 ppm to 4000 ppm, approximately 3500 ppm to 4500 ppm, approximately 4000 to 5000 ppm, and approximately 4500 ppm to 5500 ppm.

[0107] In one embodiment, including any of the foregoing embodiments, the acid source contains H2ZrF6 and / or ZrF6. 2- The concentration of the acid source in the solution is about 0.001% (w / v) to 0.0025% (w / v), about 0.002% (w / v) to 0.004% (w / v), about 0.003% (w / v) to 0.005% (w / v), about 0.004% (w / v) to 0.006% (w / v), or about 0.0045% (w / v) to 0.0065% (w / v).

[0108] In one embodiment, including any of the foregoing embodiments, the acid source contains H2ZrF6 and / or ZrF6. 2- The concentration of the acid source in the solution is about 0.03% (w / v) to 0.04% (w / v), about 0.035% (w / v) to 0.045% (w / v), about 0.04% (w / v) to 0.05% (w / v), about 0.045% (w / v) to 0.055% (w / v), or about 0.045% (w / v) to 0.06% (w / v).

[0109] In one embodiment, including any of the foregoing embodiments, the acid source contains H2ZrF6 and / or ZrF6. 2- The concentration of the acid source in the solution is approximately 10 ppm to 25 ppm, approximately 20 ppm to 40 ppm, approximately 30 ppm to 50 ppm, approximately 40 ppm to 60 ppm, or approximately 45 ppm to 65 ppm.

[0110] In one embodiment, including any of the foregoing embodiments, the acid source contains H2ZrF6 and / or ZrF6. 2- The concentration of the acid source in the solution is approximately 300 ppm to 400 ppm, approximately 350 ppm to 450 ppm, approximately 400 ppm to 500 ppm, approximately 450 ppm to 550 ppm, or approximately 450 ppm to 600 ppm.

[0111] In one embodiment, including any of the foregoing embodiments, the acid source also contains water.

[0112] In some embodiments, including any of the foregoing examples, the solution comprises a solvent. In one embodiment, the solvent is selected from the group consisting of: vinyl sulfite (ES), ethylene carbonate (EC), diethylene carbonate, dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), propyl methyl carbonate, nitroethyl carbonate, propylene carbonate (PC), diethyl carbonate (DEC), methyl propyl carbonate (MPC), dimethyl 2,5-dioxaadipic acid, tetrahydrofuran (THF), γ-butyrolactone (GBL), fluoroethylene carbonate (FEC), fluoromethyl ethylene carbonate (FMEC), methyl trifluoroethyl carbonate (F-EMC), fluorinated 3-(1,1,2,2-tetrafluoroethoxy)-1,1,2,2-tetrafluoropropane / 1,1,2,2-tetrafluoro-3-(1, 1,2,2-Tetrafluoroethoxy)propane (F-EPE), fluorinated cyclic carbonates (F-AEC), dioxolane, 1,3-propenesulfonyl lactone (PES), sulfolane, acetonitrile (ACN), succinic anionyl, heptanilic anionyl, propionitrile, malononitrile, glutaronitrile (GLN), adiponitrile (ADN), adiponitrile, glutaronitrile, acetophenone, isophorone, benzonitrile, ethyl propionate, methyl propionate, methylene disulfonate, dimethyl sulfate, dimethyl sulfoxide (DMSO), ethyl acetate, methyl butyrate, dimethyl ether (DME), diethyl ether, dioxolane, γ-butyrolactone, methyl benzoate, 2-methyl-5-oxooxazolidine-2-carboxynitrile, N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAC), and combinations thereof. In some examples, the combined solvents are those that are miscible.

[0113] In some embodiments, including any of the foregoing embodiments, the acidic solution includes the solution described in PCT application WO 2023 / 121838, filed November 30, 2022, entitled “CATHOLYTES FOR A SOLID-STATEBATTERY”, the entire contents of which are incorporated herein by reference.

[0114] In some embodiments, including any of the foregoing examples, the solution contains vinyl sulfite (ES). In some embodiments, including any of the foregoing examples, the solution contains sulfolane.

[0115] In some embodiments, including any of the foregoing examples, the solution contains a solvent selected from the group consisting of: ethylene carbonate (EC), diethylene carbonate, dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), propyl methyl carbonate, nitroethyl carbonate, propylene carbonate (PC), diethyl carbonate (DEC), methyl propyl carbonate (MPC), dimethyl 2,5-dioxaadipic acid, tetrahydrofuran (THF), γ-butyrolactone (GBL), fluoroethylene carbonate (FEC), fluoromethyl ethylene carbonate (FMEC), methyl trifluoroethyl carbonate (F-EMC), fluorinated 3-(1,1,2,2-tetrafluoroethoxy)-1,1,2,2-tetrafluoropropane / 1,1,2,2-tetrafluoro-3-(1,1,2,2-tetrafluoroethoxy)propane (F-EPE), and fluorinated cyclic carbonates (F-AEC).

[0116] In some embodiments, including any of the foregoing examples, the solution comprises a solvent selected from the group consisting of: dioxolane, 1,3-propenesulfonyl lactone (PES), sulfolane, acetonitrile (ACN), succinic anionyl, heptonitrile, octanoic anionyl, propionitrile, malononitrile, glutaronitrile (GLN), adiponitrile (ADN), adiponitrile, glutaronitrile, acetophenone, isophorone, benzonitrile, ethyl propionate, methyl propionate, and methylene disulfonate.

[0117] In some embodiments, including any of the foregoing examples, the solution contains a solvent selected from the group consisting of dimethyl sulfate, dimethyl sulfoxide (DMSO), ethyl acetate, methyl butyrate, dimethyl ether (DME), diethyl ether, dioxolane, γ-butyrolactone, methyl benzoate, and 2-methyl-5-oxooxazolidine-2-carboxynitrile.

[0118] In some embodiments, including any of the foregoing examples, the solution contains vinyl sulfite (ES) and sulfolane. In some embodiments, including any of the foregoing examples, the volume ratio (v / v) of vinyl sulfite (ES) to sulfolane is about 7:3 to about 5:5. In some embodiments, including any of the foregoing examples, the volume ratio of vinyl sulfite (ES) to sulfolane is about 9:3, about 8:3, about 7:3, about 6:3, or about 5:3. In some embodiments, including any of the foregoing examples, the volume ratio of vinyl sulfite (ES) to sulfolane is about 7:3. In some embodiments, including any of the foregoing examples, the volume ratio of vinyl sulfite (ES) to sulfolane is about 5:5.

[0119] In some embodiments, including any of the foregoing examples, the solution further contains a lithium salt. In some embodiments, including any of the foregoing examples, the concentration of the lithium salt is about 0.5 mol (M) to 5 (M). In some embodiments, including any of the foregoing examples, the solution contains vinyl sulfite (ES) and sulfolane, as well as a lithium salt, the concentration of which is about 0.5 mol (M) to 5 (M). In some embodiments, including any of the foregoing examples, the lithium salt is selected from the group consisting of: LiPF6, lithium bis(oxalato)borate (LiBOB), lithium bis(perfluoroethanesulfonyl)imide (LiBETI), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), LiBF4, LiClO4, LiAsF6, lithium bis(fluorosulfonyl)imide (LiFSI), LiF, LiI, LiBr, LiCl, and combinations thereof. In some embodiments, including any of the foregoing examples, the lithium salt is selected from LiPF6 or LiBF4. In some embodiments, including any of the foregoing examples, the lithium salt is LiBF4. In some embodiments, including any of the foregoing examples, the lithium salt is selected from 1.4M LiPF6, 1.4M LiBF4, and 1.6M LiBF4. In some embodiments, including any of the foregoing examples, the lithium salt is selected from 1.4M LiBF4 and 1.6M LiBF4.

[0120] In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing an acid selected from H3PO4, H2TiF6, HCl, H2SO4, H3BO3 and H2ZrF6; and (2) a solvent containing vinyl sulfite (ES).

[0121] In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing an acid selected from H3PO4, H2TiF6, HCl, H2SO4, H3BO3 and H2ZrF6; and (2) a solvent containing vinyl sulfite (ES) and sulfolane.

[0122] In one embodiment, including any of the foregoing embodiments, the solution comprises: (1) an acid source containing an acid selected from H3PO4, H2TiF6, HCl, H2SO4, H3BO3, and H2ZrF6; and (2) a solvent containing vinyl sulfite (ES) and sulfolane; wherein the concentration of the acid source in the solution is approximately 0.001% (w / v), approximately 0.002% (w / v), approximately 0.003% (w / v), approximately 0.004% (w / v), approximately 0.005% (w / v), approximately 0.006% (w / v), approximately 0.007% (w / v), approximately 0.008% (w / v), approximately 0.009% (w / v), approximately 0.01% (w / v), approximately 0.02% (w / v), approximately 0.03% (w / v), approximately 0.04% (w / v), or approximately 0.05%. (w / v), about 0.06% (w / v), about 0.07% (w / v), about 0.08% (w / v), about 0.09% (w / v) or about 0.1% (w / v).

[0123] In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4 and water; and (2) a solvent containing vinyl sulfite (ES).

[0124] In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4 and water; and (2) a solvent containing vinyl sulfite (ES) and sulfolane.

[0125] In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4; and (2) a solvent containing vinyl sulfite (ES) and sulfolane; the concentration of the acid source in the solution is approximately 0.001% (w / v), approximately 0.002% (w / v), approximately 0.003% (w / v), approximately 0.004% (w / v), approximately 0.005% (w / v), approximately 0.006% (w / v), approximately 0.007% (w / v), approximately 0.008% (w / v), approximately 0.009% (w / v), approximately 0.01% (w / v), approximately 0.02% (w / v), approximately 0.03% (w / v), approximately 0.04% (w / v), approximately 0.05% (w / v), approximately 0.06% (w / v), approximately 0.07% (w / v), or approximately 0.08%. (w / v), about 0.09% (w / v) or about 0.1% (w / v).

[0126] In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4; and (2) a solvent containing vinyl sulfite (ES) and sulfolane; wherein the concentration of the acid source in the acidic solution is about 0.001% (w / v) to 0.0025% (w / v), about 0.002% (w / v) to 0.004% (w / v), about 0.003% (w / v) to 0.005% (w / v), about 0.004% (w / v) to 0.006% (w / v), or about 0.0045% (w / v) to 0.0065% (w / v).

[0127] In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4; and (2) a solvent containing vinyl sulfite (ES) and sulfolane; wherein the concentration of the acid source in the acidic solution is about 0.03% (w / v) to 0.04% (w / v), about 0.035% (w / v) to 0.045% (w / v), about 0.04% (w / v) to 0.05% (w / v), about 0.045% (w / v) to 0.055% (w / v), or about 0.045% (w / v) to 0.06% (w / v).

[0128] In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4; and (2) a solvent containing vinyl sulfite (ES) and sulfolane; wherein the concentration of the acid source in the acidic solution is about 10 ppm to 25 ppm, about 20 ppm to 40 ppm, about 30 ppm to 50 ppm, about 40 ppm to 60 ppm, or about 45 ppm to 65 ppm.

[0129] In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4; and (2) a solvent containing vinyl sulfite (ES) and sulfolane; wherein the concentration of the acid source in the acidic solution is about 300 ppm to 400 ppm, about 350 ppm to 450 ppm, about 400 ppm to 500 ppm, about 450 ppm to 550 ppm, or about 450 ppm to 600 ppm.

[0130] In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4; and (2) a solvent containing vinyl sulfite (ES) and sulfolane; wherein the concentration of the acid source in the acidic solution is approximately 50 ppm.

[0131] In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4; and (2) a solvent containing vinyl sulfite (ES) and sulfolane; wherein the concentration of the acid source in the acidic solution is approximately 500 ppm.

[0132] In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4; and (2) a solvent containing vinyl sulfite (ES); the concentration of the acid source in the acidic solution is about 10 ppm to 25 ppm, about 20 ppm to 40 ppm, about 30 ppm to 50 ppm, about 40 ppm to 60 ppm, or about 45 ppm to 65 ppm. In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4; and (2) a solvent containing vinyl sulfite (ES); the concentration of the acid source in the acidic solution is about 300 ppm to 400 ppm, about 350 ppm to 450 ppm, about 400 ppm to 500 ppm, about 450 ppm to 550 ppm, or about 450 ppm to 600 ppm. In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4; and (2) a solvent containing vinyl sulfite (ES); the concentration of the acid source in the acidic solution is about 50 ppm. In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4; and (2) a solvent containing vinyl sulfite (ES); the concentration of the acid source in the acidic solution is about 500 ppm. In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4; and (2) a solvent containing vinyl sulfite (ES); the concentration of the acid source in the acidic solution is about 1000 ppm to 5500 ppm, about 2000 ppm to 5500 ppm, about 3000 ppm to 5500 ppm, or about 4000 ppm to 5500 ppm. In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4; and (2) a solvent containing vinyl sulfite (ES); wherein the concentration of the acid source in the acidic solution is approximately 1000 ppm to 2000 ppm, approximately 1500 ppm to 2500 ppm, approximately 2000 ppm to 3000 ppm, approximately 2500 ppm to 3500 ppm, approximately 3000 ppm to 4000 ppm, approximately 3500 ppm to 4500 ppm, approximately 4000 ppm to 5000 ppm, or approximately 4500 ppm to 5500 ppm. In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4; and (2) a solvent containing vinyl sulfite (ES); wherein the concentration of the acid source in the acidic solution is approximately 5000 ppm.In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4; and (2) a solvent containing vinyl sulfite (ES); the concentration of the acid source in the acidic solution is approximately 5500 ppm.

[0133] In one embodiment, including any of the foregoing embodiments, the acid source further contains water. For example, in one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4 and water; and (2) a solvent containing vinyl sulfite (ES) and sulfolane; the concentration of the acid source in the acidic solution is about 10 ppm to 25 ppm, about 20 ppm to 40 ppm, about 30 ppm to 50 ppm, about 40 ppm to 60 ppm, or about 45 ppm to 65 ppm. In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4 and water; and (2) a solvent containing vinyl sulfite (ES) and sulfolane; the concentration of the acid source in the acidic solution is about 50 ppm.

[0134] In one embodiment, including any of the foregoing embodiments, the acid source further contains water. For example, in one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4 and water; and (2) a solvent containing vinyl sulfite (ES); the concentration of the acid source in the acidic solution is about 10 ppm to 25 ppm, about 20 ppm to 40 ppm, about 30 ppm to 50 ppm, about 40 ppm to 60 ppm, or about 45 ppm to 65 ppm. In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4 and water; and (2) a solvent containing vinyl sulfite (ES); the concentration of the acid source in the acidic solution is about 50 ppm.

[0135] In some embodiments, the bilayer is in contact with the solution, the bilayer is immersed in the solution, the bilayer is immersed in the solution during solution recirculation, the bilayer is immersed in the solution during solution sonication, the bilayer is immersed in the solution during solution gas bubbling, the solution is sprayed onto the bilayer, the solution is dispensed onto the bilayer in a constant flow manner, or a combination thereof. In one embodiment, the bilayer is in contact with the solution. In one embodiment, the bilayer is immersed in the solution. In one embodiment, the bilayer is immersed in the solution during solution recirculation. In one embodiment, the bilayer is immersed in the solution during solution sonication. In one embodiment, the bilayer is immersed in the solution during solution gas bubbling. In one embodiment, the solution is sprayed onto the bilayer. In one embodiment, the solution is dispensed onto the bilayer in a constant flow manner.

[0136] In some embodiments, the bilayer contacts the solution for at least about 1 second, at least about 10 seconds, at least about 30 seconds, at least about 1 minute, at least about 2 minutes, at least about 3 minutes, at least about 4 minutes, at least about 5 minutes, at least about 10 minutes, at least about 15 minutes, at least about 20 minutes, at least about 25 minutes, at least about 30 minutes, at least about 35 minutes, at least about 40 minutes, at least about 45 minutes, at least about 50 minutes, at least about 55 minutes, or at least about 60 minutes.

[0137] In some embodiments, the bilayer contacts the solution for no more than about 2 hours, no more than about 1 hour and 45 minutes, no more than about 1 hour and 30 minutes, no more than about 1 hour and 15 minutes, no more than about 1 hour, no more than about 45 minutes, no more than about 30 minutes, no more than about 15 minutes, no more than about 10 minutes, no more than about 5 minutes, no more than about 4 minutes, no more than about 3 minutes, no more than about 2 minutes, or no more than about 1 minute.

[0138] In some embodiments, the bilayer is immersed in the solution for at least about 1 second, at least about 10 seconds, at least about 30 seconds, at least about 1 minute, at least about 2 minutes, at least about 3 minutes, at least about 4 minutes, at least about 5 minutes, at least about 10 minutes, at least about 15 minutes, at least about 20 minutes, at least about 25 minutes, at least about 30 minutes, at least about 35 minutes, at least about 40 minutes, at least about 45 minutes, at least about 50 minutes, at least about 55 minutes, or at least about 60 minutes.

[0139] In some embodiments, the bilayer is immersed in the solution for no more than about 2 hours, no more than about 1 hour and 45 minutes, no more than about 1 hour and 30 minutes, no more than about 1 hour and 15 minutes, no more than about 1 hour, no more than about 45 minutes, no more than about 30 minutes, no more than about 15 minutes, no more than about 10 minutes, no more than about 5 minutes, no more than about 4 minutes, no more than about 3 minutes, no more than about 2 minutes, or no more than about 1 minute.

[0140] In one embodiment, the bilayer is in contact with the solution at a temperature of about 18°C ​​to 65°C, about 40°C to 60°C, about 50°C to 60°C, about 20°C to 40°C, about 30°C to 40°C, about 20°C to 30°C, or about 20°C to 25°C. In another embodiment, the bilayer is in contact with the solution at a temperature of about 20°C to 22°C.

[0141] In one embodiment, the bilayer is immersed in the solution at a temperature of about 18°C ​​to 65°C, about 40°C to 60°C, about 50°C to 60°C, about 20°C to 40°C, about 30°C to 40°C, about 20°C to 30°C, or about 20°C to 25°C. In another embodiment, the bilayer is immersed in the solution at a temperature of about 20°C to 22°C.

[0142] In one embodiment, the bilayer is immersed in the solution during solution recirculation at a temperature of about 18°C ​​to 65°C, about 40°C to 60°C, about 50°C to 60°C, about 20°C to 40°C, about 30°C to 40°C, about 20°C to 30°C, or about 20°C to 25°C. In another embodiment, the bilayer is immersed in the solution during solution recirculation at a temperature of about 20°C to 22°C.

[0143] In one embodiment, the bilayer is immersed in the solution during ultrasonic treatment at a temperature of about 18°C ​​to 65°C, about 40°C to 60°C, about 50°C to 60°C, about 20°C to 40°C, about 30°C to 40°C, about 20°C to 30°C, or about 20°C to 25°C. In another embodiment, the bilayer is immersed in the solution during ultrasonic treatment at a temperature of about 20°C to 22°C.

[0144] In one embodiment, the bilayer is immersed in the solution during gas bubbling at a temperature of about 18°C ​​to 65°C, about 40°C to 60°C, about 50°C to 60°C, about 20°C to 40°C, about 30°C to 40°C, about 20°C to 30°C, or about 20°C to 25°C. In another embodiment, the bilayer is immersed in the solution during gas bubbling at a temperature of about 20°C to 22°C.

[0145] In some embodiments, the bilayer is cut before contact with the solution. In other embodiments, the bilayer is cut after contact with the solution.

[0146] In some embodiments, the bilayer is annealed before contact with the solution. An exemplary annealing process is described in U.S. Patent No. 9,966,630 B2, entitled “ANNEALED GARNET ELECTROLYTES,” issued May 8, 2018, the entire contents of which are incorporated herein by reference for all purposes. In some embodiments, the film is annealed in a reducing atmosphere and heated at elevated temperatures. In some embodiments, the heating temperature is 500°C to 800°C, and the reducing atmosphere is Ar:H2 or Ar or an inert atmosphere. In some embodiments, the bilayer is heated at elevated temperatures for 30 minutes to 2 hours during the annealing process.

[0147] In some embodiments, including any of the foregoing examples, the method further includes (d): contacting the acid-treated bilayer with a first rinsing solution for about 1 second to 5 minutes, and removing the acid-treated bilayer from the first rinsing solution to obtain a rinsed acid-treated bilayer. In some embodiments, step (d) is performed for about 1 second to 1 minute. In some embodiments, step (d) is performed for about 1 second, about 3 seconds, about 5 seconds, about 10 seconds, about 15 seconds, about 20 seconds, 30 seconds, about 1 minute, about 2 minutes, about 3 minutes, about 4 minutes, or about 5 minutes.

[0148] In some embodiments, including any of the foregoing embodiments, the rinsing solution in step (d) comprises the solution described in PCT application WO 2023 / 121838, filed November 30, 2022, entitled “CATHOLYTES FOR A SOLID-STATE BATTERY”.

[0149] In some embodiments, including any of the foregoing examples, the rinsing solution in step (d) comprises a solvent selected from the group consisting of: vinyl sulfite (ES), ethylene carbonate (EC), diethylene carbonate, dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), propyl methyl carbonate, nitroethyl carbonate, propylene carbonate (PC), diethyl carbonate (DEC), methyl propyl carbonate (MPC), dimethyl 2,5-dioxaadipic acid, tetrahydrofuran (THF), γ-butyrolactone (GBL), fluoroethylene carbonate (FEC), fluoromethyl ethylene carbonate (FMEC), methyl trifluoroethyl carbonate (F-EMC), fluorinated 3-(1,1,2,2-tetrafluoroethoxy)-1,1,2,2-tetrafluoropropane / 1,1,2,2-tetrafluoro-3-(1, 1,2,2-Tetrafluoroethoxy)propane (F-EPE), fluorinated cyclic carbonates (F-AEC), dioxolane, 1,3-propenesulfonyl lactone (PES), sulfolane, acetonitrile (ACN), succinic anionyl, heptanilic anionyl, propionitrile, malononitrile, glutaronitrile (GLN), adiponitrile (ADN), adiponitrile, glutaronitrile, acetophenone, isophorone, benzonitrile, ethyl propionate, methyl propionate, methylene disulfonate, dimethyl sulfate, dimethyl sulfoxide (DMSO), ethyl acetate, methyl butyrate, dimethyl ether (DME), diethyl ether, dioxolane, γ-butyrolactone, methyl benzoate, 2-methyl-5-oxooxazolidine-2-carboxynitrile, N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAC), and combinations thereof.

[0150] In some embodiments, including any of the foregoing examples, the rinsing solution in step (d) comprises vinyl sulfite (ES).

[0151] In some embodiments, the method further includes step (e): contacting the acid-treated bilayer with a second rinsing solution for about 1 second to 5 minutes, and removing the acid-treated bilayer from the second rinsing solution to obtain a rinsed acid-treated bilayer. In some embodiments, step (e) is performed for about 1 second to 1 minute. In some embodiments, step (e) is performed for about 1 second, about 3 seconds, about 5 seconds, about 10 seconds, about 15 seconds, about 20 seconds, 30 seconds, about 1 minute, about 2 minutes, about 3 minutes, about 4 minutes, or about 5 minutes.

[0152] In some embodiments, including any of the foregoing examples, the rinsing solution in step (e) comprises a solvent selected from the group consisting of: vinyl sulfite (ES), ethylene carbonate (EC), diethylene carbonate, dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), propyl methyl carbonate, nitroethyl carbonate, propylene carbonate (PC), diethyl carbonate (DEC), methyl propyl carbonate (MPC), dimethyl 2,5-dioxaadipic acid, tetrahydrofuran (THF), γ-butyrolactone (GBL), fluoroethylene carbonate (FEC), fluoromethyl ethylene carbonate (FMEC), methyl trifluoroethyl carbonate (F-EMC), fluorinated 3-(1,1,2,2-tetrafluoroethoxy)-1,1,2,2-tetrafluoropropane / 1,1,2,2-tetrafluoro-3-(1, 1,2,2-Tetrafluoroethoxy)propane (F-EPE), fluorinated cyclic carbonates (F-AEC), dioxolane, 1,3-propenesulfonyl lactone (PES), sulfolane, acetonitrile (ACN), succinic anionyl, heptanilic anionyl, propionitrile, malononitrile, glutaronitrile (GLN), adiponitrile (ADN), adiponitrile, glutaronitrile, acetophenone, isophorone, benzonitrile, ethyl propionate, methyl propionate, methylene disulfonate, dimethyl sulfate, dimethyl sulfoxide (DMSO), ethyl acetate, methyl butyrate, dimethyl ether (DME), diethyl ether, dioxolane, γ-butyrolactone, methyl benzoate, 2-methyl-5-oxooxazolidine-2-carboxynitrile, N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAC), and combinations thereof.

[0153] In some embodiments, including any of the foregoing examples, the rinsing solution in step (e) comprises acetonitrile (ACN).

[0154] In other embodiments, including any of the foregoing embodiments, the method further includes step (f): drying the rinsed acid-treated bilayer. In some embodiments, the method of treating the bilayer includes the following steps: (a) providing a solution containing an acid source, the acid source containing an acid selected from H3PO4, H2TiF6, HCl, H2SO4, H3BO3, H2ZrF6 and combinations thereof, at a concentration of 10 ppm to 5500 ppm, the solvent containing vinyl sulfite; (b) contacting the bilayer with the solution for about one hour or less; (c) removing the bilayer from the solution to obtain an acid-treated bilayer; (d) contacting the acid-treated bilayer with a first rinsing solution containing vinyl sulfite for about 1 second to 5 minutes, and removing the acid-treated bilayer from the first rinsing solution; (e) contacting the acid-treated bilayer with a second rinsing solution containing acetonitrile for about 1 second to 5 minutes, and removing the acid-treated bilayer from the second rinsing solution to obtain a rinsed acid-treated bilayer.

[0155] In some embodiments, the method of processing a bilayer includes the following steps: (a) providing a solution containing an acid source, said acid source containing H3PO4 and / or H2PO4. - and / or PO4 3- and / or PO4 2- (a) The concentration is 10 ppm to 5500 ppm, and the solvent contains vinyl sulfite; (b) The bilayer is contacted with the solution for about one hour or less; (c) The bilayer is removed from the solution to obtain an acid-treated bilayer; (d) The acid-treated bilayer is contacted with a first rinsing solution containing vinyl sulfite for about 1 second to 5 minutes, and the acid-treated bilayer is removed from the first rinsing solution; (e) The acid-treated bilayer is contacted with a second rinsing solution containing acetonitrile for about 1 second to 5 minutes, and the acid-treated bilayer is removed from the second rinsing solution to obtain a rinsed acid-treated bilayer.

[0156] In some embodiments, the method of processing a bilayer includes the following steps: (a) providing a solution containing an acid source, said acid source containing H2SO4 and / or HSO4 - and / or SO4 2- and / or SO4 - (a) The concentration is 10 ppm to 5500 ppm, and the solvent contains vinyl sulfite; (b) The bilayer is contacted with the solution for about one hour or less; (c) The bilayer is removed from the solution to obtain an acid-treated bilayer; (d) The acid-treated bilayer is contacted with a first rinsing solution containing vinyl sulfite for about 1 second to 5 minutes, and the acid-treated bilayer is removed from the first rinsing solution; (e) The acid-treated bilayer is contacted with a second rinsing solution containing acetonitrile for about 1 second to 5 minutes, and the acid-treated bilayer is removed from the second rinsing solution to obtain a rinsed acid-treated bilayer.

[0157] In some embodiments, the method of processing a bilayer includes the following steps: (a) providing a solution containing an acid source, said acid source containing HCl and / or Cl... - (a) The concentration is 10 ppm to 5500 ppm, and the solvent contains vinyl sulfite; (b) The bilayer is contacted with the solution for about one hour or less; (c) The bilayer is removed from the solution to obtain an acid-treated bilayer; (d) The acid-treated bilayer is contacted with a first rinsing solution containing vinyl sulfite for about 1 second to 5 minutes, and the acid-treated bilayer is removed from the first rinsing solution; (e) The acid-treated bilayer is contacted with a second rinsing solution containing acetonitrile for about 1 second to 5 minutes, and the acid-treated bilayer is removed from the second rinsing solution to obtain a rinsed acid-treated bilayer.

[0158] In some embodiments, the method of treating a bilayer includes the following steps: (a) providing a solution containing an acid source, said acid source including H3PO4 in an aqueous solution at a concentration of 10 ppm to 5500 ppm, the solvent containing vinyl sulfite; (b) contacting the bilayer with the solution for about one hour or less; (c) removing the bilayer from the solution to obtain an acid-treated bilayer; (d) contacting the acid-treated bilayer with a first rinsing solution containing vinyl sulfite for about 1 second to 5 minutes, and removing the acid-treated bilayer from the first rinsing solution; (e) contacting the acid-treated bilayer with a second rinsing solution containing acetonitrile for about 1 second to 5 minutes, and removing the acid-treated bilayer from the second rinsing solution to obtain a rinsed acid-treated bilayer.

[0159] In some embodiments, step (b) is performed continuously. In some embodiments, steps (b) and (c) are performed continuously. In some embodiments, steps (b), (c), and (d) are performed continuously. In some embodiments, steps (b), (c), (d), and (e) are performed continuously. In some embodiments, steps (b), (c), (d), (e), and (f) are performed continuously. In some embodiments, each part of the acid treatment process is performed continuously.

[0160] In some embodiments, the bilayer is in continuous contact with the solution. In some embodiments, the bilayer is continuously immersed in the solution. In some embodiments, the bilayer is continuously immersed in the solution during solution recirculation. In some embodiments, the bilayer is continuously immersed in the solution during solution sonication. In some embodiments, the bilayer is continuously immersed in the solution during solution gas bubbling. In some embodiments, the bilayer is continuously sprayed with the solution. In some embodiments, the solution is continuously dispensed onto the bilayer in a constant flow.

[0161] In some embodiments, the double-layered magnetic sheet remains flat during step (b). In some embodiments, the double-layered magnetic sheet remains flat during steps (b) and (c). In some embodiments, the double-layered magnetic sheet remains flat during steps (b), (c), and (d). In some embodiments, the double-layered magnetic sheet remains flat during steps (b), (c), (d), and (e). In some embodiments, the double-layered magnetic sheet remains flat during steps (b), (c), (d), (e), and (f).

[0162] In some embodiments, the lithium-filled garnet layer in the bilayer is a lithium-filled garnet film.

[0163] In some embodiments, including any of the foregoing embodiments, the lithium-filled garnet layer conforms to the chemical formula Li A La B Al C M'' D Zr E O F before step (b), where 5 < A < 8, 1.5 < B < 4, 0.1 < C < 2, 0 ≤ D < 2, 0 ≤ E < 2.5, 10 < F < 13, and M'' is selected from the group consisting of Mo, W, Nb, Y, Ta, Ga, Sb, Ca, Ba, Sr, Ce, Hf, and Rb. In some examples, M' and M'' are the same element, selected from Al, Mo, W, Nb, Sb, Ca, Ba, Sr, Ce, Hf, Rb, and Ta. However, unless there is a clear indication to the contrary, M' and M'' are not the same element.

[0164] In some embodiments, including any of the foregoing embodiments, the lithium-filled garnet layer conforms to the chemical formula Li a La b Zr c O d Al e before step (b), where 5 ≤ a ≤ 8, 2 ≤ b ≤ 4, 1 ≤ c ≤ 2, 11 ≤ d ≤ 14, 0 ≤ e ≤ 1, and the chemical formula Li a La b Zr c O d Al e is electrically neutral by selecting a, b, c, d, and e. In some embodiments, including any of the foregoing embodiments, a is 6, 6.25, 6.50, 6.75, or 7. In some embodiments, including any of the foregoing embodiments, e is 0, 0.25, 0.5, 0.75, or 1. In some embodiments, including any of the foregoing embodiments, b is 3, z is 2. In some embodiments, including any of the foregoing embodiments, d is 12. In some embodiments, including any of the foregoing embodiments, a is 6.25, b is 3, c is 2, d is 12, e is 0.25. In some embodiments, including any of the foregoing embodiments, a is approximately 6.25, b is approximately 3, c is approximately 2, d is approximately 12, e is approximately 0.25.

[0165] In some embodiments, including any of the foregoing embodiments, the lithium-filled garnet layer conforms to the chemical formula Li x La3Zr2O 12 + yAl2O3, where x is from 5.8 to 7.0 and y is 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 1.0.

[0166] In some embodiments, including any of the foregoing embodiments, the lithium-filled garnet layer conforms to a chemical formula selected from the group consisting of: Li A La B M' C M'' D Zr E O F 、Li A La B M' C M'' D Ta E O F and Li A La B M' C M'' D Nb E O F , where 4 < A < 8.5, 1.5 < B < 4, 0 ≤ C < 2, 0 ≤ D < 2, 0 < E < 2, 10 < F < 14, and M' and M'' are each independently selected from the group consisting of: Al, Mo, W, Nb, Sb, Ca, Ba, Sr, Ce, Hf, Rb, and Ta. In some embodiments, including any of the foregoing embodiments, the lithium-filled garnet layer conforms to the chemical formula Li a La b Zr c Al d M'' e O f , where 5 < a < 7.7, 2 < b < 4, 0 ≤ c < 2.5, 0 < d < 2, 0 ≤ e < 2, 10 < f < 14, and M'' is a metal selected from Nb, Ta, V, W, Mo, and Sb.

[0167] In some embodiments, including any of the foregoing embodiments, the lithium-filled garnet layer conforms to the chemical formula Li a La b Zr c Al d O f , where 5 < a < 7.7, 2 < b < 4, 0 < c < 2.5, 0 < d < 2, 10 < f < 14. In some embodiments, including any of the foregoing embodiments, the lithium-filled garnet layer conforms to the chemical formula Li x La3Zr2O 12 ·0.35Al2O3, where 4 < x < 8.5. In some embodiments, including any of the foregoing embodiments, the lithium-filled garnet layer conforms to the chemical formula Li x La3Zr2O 12 ·0.5Al2O3, where 4 < x < 8.5.

[0168] In some embodiments, including any of the foregoing embodiments, the lithium-filled garnet layer conforms to the chemical formula: Li x La3Zr2O 12 ·0.65Al2O3, where 4 < x < 8.5. In some embodiments, including any of the foregoing embodiments, the lithium-filled garnet layer conforms to the chemical formula Li x La3Zr2O 12 ·Al2O3, where 4 < x < 8.5. In some embodiments, including any of the foregoing embodiments, the lithium-filled garnet layer conforms to a chemical formula selected from the group consisting of: Li A La B M' C M'' D Zr E O F 、Li A La B M' C M'' D Ta E O F 和Li A La B M' C M'' D Nb E O F , where 4 < A < 8.5, 1.5 < B < 4, 0 ≤ C < 2.5, 0 ≤ D < 2.5, 0 < E < 2.5, 10 < F < 14, and M' and M'' are each independently selected from the group consisting of: Al, Mo, W, Nb, Ga, Y, Gd,Sb, Ca, Ba, Sr, Ce, Hf, Rb, and Ta.

[0169] In some embodiments, including any of the foregoing embodiments, the lithium-filled garnet layer conforms to the chemical formula Li a La b Zr c Al d M'' e O f , where 5 < a < 7.7, 2 < b < 4, 0 < c < 2.5, 0 < d < 2.5, 0 ≤ e < 2.5, 10 < f < 14, and M'' is a metal selected from Nb, Ta, V, W, Mo, and Sb. In some embodiments, including any of the foregoing embodiments, the lithium-filled garnet layer conforms to the chemical formula Li a La b Zr c Al d O f, of which 5 <a<7.7、2<b<4、0<c<2.5、0<d<2.5、10<f<14。

[0170] In some embodiments, including any of the foregoing embodiments, the lithium-filled garnet layer is approximately Li7La3Zr2O. 12 Approximately Li 6.25 La3Zr2O 12 Al 0.25 Approximately Li 5.5 La3Zr2O 12 Al 0.5 Approximately Li 4.75 La3Zr2O 12 Al 0.75 Or approximately Li4La3Zr2O 12 Al.

[0171] In some embodiments, including any of the foregoing embodiments, the lithium-filled garnet layer is Li7La3Zr2O 12 Li 6.25 La3Zr2O 12 Al 0.25 Li 5.5 La3Zr2O 12 Al 0.5 Li 4.75 La3Zr2O 12 Al 0.75 or Li4La3Zr2O 12 Al.

[0172] In some embodiments, the bilayer prior to step (b) includes contaminants.

[0173] In some embodiments, including any of the foregoing embodiments, the contaminant is selected from the group consisting of hydroxides, peroxides, oxides, carbonates, and combinations thereof.

[0174] In some examples, the bilayer after step (c) contains an acid and / or its conjugate base and / or its ions incorporated or bonded to the bilayer. In some examples, the bilayer after step (c) contains an acid and / or its conjugate base and / or its ions incorporated or bonded to the surface of the lithium-filled garnet layer in the bilayer.

[0175] In some examples, the bilayer after step (c) contains H3PO4 and / or its conjugate base H2PO4 incorporated or bonded to the bilayer. - and / or its ions PO4 3- and / or PO4 2-In some examples, the bilayer after step (c) contains H3PO4 and / or its conjugate base H2PO4 incorporated or bonded to the surface of the lithium-filled garnet layer in the bilayer. - and / or its ions PO4 3- and / or PO4 2- In some examples, the bilayer after step (c) contains H2TiF6 and / or its ionic TiF6 incorporated or bonded to the bilayer. 2- In some examples, the bilayer after step (c) contains H2TiF6 and / or its ionic TiF6 incorporated or bonded to the surface of the lithium-filled garnet layer in the bilayer. 2- In some examples, the bilayer after step (c) contains HCl and / or its conjugate base Cl incorporated or bonded to the bilayer. - In some examples, the bilayer after step (c) contains HCl and / or its conjugate base Cl- doped or bonded to the surface of the lithium-filled garnet layer in the bilayer. - .

[0176] In some examples, the bilayer after step (c) contains H2SO4 incorporated or bonded to the bilayer and / or its conjugate base HSO4. - and / or its ions SO4 2- and / or SO4 - In some examples, the bilayer after step (c) contains H₂SO₄ and / or its conjugate base HSO₄ incorporated or bonded to the surface of the lithium-filled garnet layer in the bilayer. - and / or its ions SO4 2- and / or SO4 - .

[0177] In some examples, the bilayer following step (c) includes a phosphorus-containing layer containing Li3PO4, LiH2PO4, Li2HPO4, Li(CH3)2PO4 (i.e., lithium dimethyl phosphate), Li2(CH3)PO4 (i.e., dilithium methyl phosphate), Li4P2O7, or combinations thereof. In some examples, the lithium-filled garnet layer in the bilayer following step (c) includes a phosphorus-containing layer containing Li3PO4, LiH2PO4, Li2HPO4, Li(CH3)2PO4, Li2(CH3)PO4, Li4P2O7, or combinations thereof.

[0178] In some examples, the bilayer after step (c) contains Li3PO4. In some examples, the bilayer after step (c) contains LiH2PO4. In some examples, the bilayer after step (c) contains Li2HPO4. In some examples, the bilayer after step (c) contains Li(CH3)2PO4. In some examples, the bilayer after step (c) contains Li2(CH3)PO4. In some examples, the bilayer after step (c) contains Li4P2O7.

[0179] In some examples, the lithium-filled garnet layer in the bilayer after step (c) contains Li3PO4. In some examples, the lithium-filled garnet layer in the bilayer after step (c) contains LiH2PO4. In some examples, the lithium-filled garnet layer in the bilayer after step (c) contains Li2HPO4. In some examples, the lithium-filled garnet layer in the bilayer after step (c) contains Li(CH3)2PO4. In some examples, the lithium-filled garnet layer in the bilayer after step (c) contains Li2(CH3)PO4. In some examples, the lithium-filled garnet layer in the bilayer after step (c) contains Li4P2O7.

[0180] In some examples, the bilayer following step (c) includes a partially phosphorus-containing layer containing Li3PO4, LiH2PO4, Li2HPO4, Li(CH3)2PO4, Li2(CH3)PO4, Li4P2O7, or combinations thereof. In some examples, the lithium-filled garnet layer in the bilayer following step (c) includes a partially phosphorus-containing layer containing Li3PO4, LiH2PO4, Li2HPO4, Li(CH3)2PO4, Li2(CH3)PO4, Li4P2O7, or combinations thereof.

[0181] In some examples, the bilayer following step (c) comprises a continuous phosphorus-containing layer containing Li3PO4, LiH2PO4, Li2HPO4, Li(CH3)2PO4, Li2(CH3)PO4, Li4P2O7, or combinations thereof. In some examples, the lithium-filled garnet layer in the bilayer following step (c) comprises a continuous phosphorus-containing layer containing Li3PO4, LiH2PO4, Li2HPO4, Li(CH3)2PO4, Li2(CH3)PO4, Li4P2O7, or combinations thereof.

[0182] In some examples, the bilayer following step (c) comprises a discontinuous phosphorus-containing layer containing Li3PO4, LiH2PO4, Li2HPO4, Li(CH3)2PO4, Li2(CH3)PO4, Li4P2O7, or combinations thereof. In some examples, the lithium-filled garnet layer in the bilayer following step (c) comprises a discontinuous phosphorus-containing layer containing Li3PO4, LiH2PO4, Li2HPO4, Li(CH3)2PO4, Li2(CH3)PO4, Li4P2O7, or combinations thereof.

[0183] In some embodiments, the bilayer after step (c) contains members selected from the group consisting of phosphorus (P), titanium (Ti), chlorine (Cl), sulfur (S), boron (B), zirconium (Zr), and combinations thereof, with a content greater than 0.05 atomic percent as measured by X-ray photoelectron spectroscopy (XPS). In some embodiments, the lithium-filled garnet layer in the bilayer after step (c) contains members selected from the group consisting of phosphorus (P), titanium (Ti), chlorine (Cl), sulfur (S), boron (B), zirconium (Zr), and combinations thereof, with a content greater than 0.05 atomic percent as measured by X-ray photoelectron spectroscopy (XPS).

[0184] In some embodiments, the bilayer after step (c) contains members selected from the group consisting of phosphorus (P), titanium (Ti), chlorine (Cl), sulfur (S), boron (B), zirconium (Zr), and combinations thereof, with a content greater than 0.1 atomic percent as measured by XPS. In some embodiments, the lithium-filled garnet layer in the bilayer after step (c) contains members selected from the group consisting of phosphorus (P), titanium (Ti), chlorine (Cl), sulfur (S), boron (B), zirconium (Zr), and combinations thereof, with a content greater than 0.1 atomic percent as measured by XPS.

[0185] In some embodiments, the bilayer after step (c) contains members selected from the group consisting of phosphorus (P), titanium (Ti), chlorine (Cl), sulfur (S), boron (B), zirconium (Zr), and combinations thereof, with a content greater than 0.2 atomic percent as measured by XPS. In some embodiments, the lithium-filled garnet layer in the bilayer after step (c) contains members selected from the group consisting of phosphorus (P), titanium (Ti), chlorine (Cl), sulfur (S), boron (B), zirconium (Zr), and combinations thereof, with a content greater than 0.2 atomic percent as measured by XPS.

[0186] In some embodiments, the bilayer after step (c) contains phosphorus, with a content greater than 0.05 atomic percent, greater than 0.1 atomic percent, or greater than 0.2 atomic percent as measured by XPS. In some embodiments, the lithium-filled garnet layer in the bilayer after step (c) contains phosphorus, with a content greater than 0.05 atomic percent, greater than 0.1 atomic percent, or greater than 0.2 atomic percent as measured by XPS.

[0187] In some embodiments, the bilayer after step (c) contains titanium, the content of which, as measured by XPS, is greater than 0.05 atomic percent, greater than 0.1 atomic percent, or greater than 0.2 atomic percent. In some embodiments, the lithium-filled garnet layer in the bilayer after step (c) contains titanium, the content of which, as measured by XPS, is greater than 0.05 atomic percent, greater than 0.1 atomic percent, or greater than 0.2 atomic percent.

[0188] In some embodiments, the bilayer after step (c) contains chloride or chlorine or a combination thereof, and its content is greater than 0.05 atomic percent, greater than 0.1 atomic percent, or greater than 0.2 atomic percent as measured by XPS. In some embodiments, the lithium-filled garnet layer in the bilayer after step (c) contains chloride or chlorine or a combination thereof, and its content is greater than 0.05 atomic percent, greater than 0.1 atomic percent, or greater than 0.2 atomic percent as measured by XPS.

[0189] In some embodiments, the bilayer after step (c) contains sulfur, and its content is greater than 0.05 atomic percent, greater than 0.1 atomic percent, or greater than 0.2 atomic percent as measured by XPS. In some embodiments, the lithium-filled garnet layer in the bilayer after step (c) contains sulfur, and its content is greater than 0.05 atomic percent, greater than 0.1 atomic percent, or greater than 0.2 atomic percent as measured by XPS.

[0190] In some embodiments, the bilayer after step (c) contains boron, and its content is greater than 0.05 atomic percent, greater than 0.1 atomic percent, or greater than 0.2 atomic percent as measured by XPS. In some embodiments, the lithium-filled garnet layer in the bilayer after step (c) contains boron, and its content is greater than 0.05 atomic percent, greater than 0.1 atomic percent, or greater than 0.2 atomic percent as measured by XPS.

[0191] In some embodiments, the bilayer after step (c) contains zirconium, the content of which, as measured by XPS, is greater than 0.05 atomic percent, greater than 0.1 atomic percent, or greater than 0.2 atomic percent. In some embodiments, the lithium-filled garnet layer in the bilayer after step (c) contains zirconium, the content of which, as measured by XPS, is greater than 0.05 atomic percent, greater than 0.1 atomic percent, or greater than 0.2 atomic percent.

[0192] In some embodiments, the bilayer following step (c) contains members selected from the group consisting of phosphorus, titanium, chloride, chlorine, sulfur, boron, zirconium, and combinations thereof, with a penetration depth of approximately 1 μm to 20 μm as measured by XPS. In some embodiments, the lithium-filled garnet layer in the bilayer following step (c) contains members selected from the group consisting of phosphorus, titanium, chloride, chlorine, sulfur, boron, zirconium, and combinations thereof, with a penetration depth of approximately 1 μm to 20 μm as measured by XPS.

[0193] In some embodiments, the bilayer following step (c) contains members selected from the group consisting of phosphorus, titanium, chloride, chlorine, sulfur, boron, zirconium, and combinations thereof, with a penetration depth of approximately 1 μm to 2 μm as measured by XPS. In some embodiments, the lithium-filled garnet layer in the bilayer following step (c) contains members selected from the group consisting of phosphorus, titanium, chloride, chlorine, sulfur, boron, zirconium, and combinations thereof, with a penetration depth of approximately 1 μm to 2 μm as measured by XPS.

[0194] In some embodiments, the bilayer following step (c) contains members selected from the group consisting of phosphorus, titanium, chloride, chlorine, sulfur, boron, zirconium, and combinations thereof, with a penetration depth of approximately 1 μm to 5 μm as measured by XPS. In some embodiments, the lithium-filled garnet layer in the bilayer following step (c) contains members selected from the group consisting of phosphorus, titanium, chloride, chlorine, sulfur, boron, zirconium, and combinations thereof, with a penetration depth of approximately 1 μm to 5 μm as measured by XPS.

[0195] In some embodiments, the bilayer following step (c) contains members selected from the group consisting of phosphorus, titanium, chloride, chlorine, sulfur, boron, zirconium, and combinations thereof, with a penetration depth of approximately 5 μm to 10 μm as measured by XPS. In some embodiments, the lithium-filled garnet layer in the bilayer following step (c) contains members selected from the group consisting of phosphorus, titanium, chloride, chlorine, sulfur, boron, zirconium, and combinations thereof, with a penetration depth of approximately 5 μm to 10 μm as measured by XPS.

[0196] In some embodiments, the bilayer following step (c) contains members selected from the group consisting of phosphorus, titanium, chloride, chlorine, sulfur, boron, zirconium, and combinations thereof, with a penetration depth of approximately 10 μm to 15 μm as measured by XPS. In some embodiments, the lithium-filled garnet layer in the bilayer following step (c) contains members selected from the group consisting of phosphorus, titanium, chloride, chlorine, sulfur, boron, zirconium, and combinations thereof, with a penetration depth of approximately 10 μm to 15 μm as measured by XPS.

[0197] In some embodiments, the bilayer following step (c) contains members selected from the group consisting of phosphorus, titanium, chloride, chlorine, sulfur, boron, zirconium, and combinations thereof, with a penetration depth of approximately 15 μm to 20 μm as measured by XPS. In some embodiments, the lithium-filled garnet layer in the bilayer following step (c) contains members selected from the group consisting of phosphorus, titanium, chloride, chlorine, sulfur, boron, zirconium, and combinations thereof, with a penetration depth of approximately 15 μm to 20 μm as measured by XPS.

[0198] In some embodiments, XPS measurements show that the bilayer after step (c) contains phosphorus with a penetration depth of approximately 1 μm to 20 μm. In some embodiments, XPS measurements show that the lithium-filled garnet layer in the bilayer after step (c) contains phosphorus with a penetration depth of approximately 1 μm to 20 μm.

[0199] In some embodiments, XPS measurements show that the bilayer after step (c) contains phosphorus, with a penetration depth of approximately 1 μm to 2 μm, approximately 1 μm to 5 μm, or approximately 1 μm to 10 μm. In some embodiments, XPS measurements show that the lithium-filled garnet layer in the bilayer after step (c) contains phosphorus, with a penetration depth of approximately 1 μm to 2 μm, approximately 1 μm to 5 μm, or approximately 1 μm to 10 μm.

[0200] In some embodiments, XPS measurements show that the bilayer after step (c) contains titanium with a penetration depth of approximately 1 μm to 20 μm. In some embodiments, XPS measurements show that the lithium-filled garnet layer in the bilayer after step (c) contains titanium with a penetration depth of approximately 1 μm to 20 μm.

[0201] In some embodiments, XPS measurements show that the bilayer after step (c) contains titanium with a penetration depth of approximately 1 μm to 2 μm, approximately 1 μm to 5 μm, or approximately 1 μm to 10 μm. In some embodiments, XPS measurements show that the lithium-filled garnet layer in the bilayer after step (c) contains titanium with a penetration depth of approximately 1 μm to 2 μm, approximately 1 μm to 5 μm, or approximately 1 μm to 10 μm.

[0202] In some embodiments, XPS measurements show that the bilayer after step (c) contains chloride or chlorine or a combination thereof, with a penetration depth of approximately 1 μm to 20 μm. In some embodiments, XPS measurements show that the lithium-filled garnet layer in the bilayer after step (c) contains chloride or chlorine or a combination thereof, with a penetration depth of approximately 1 μm to 20 μm.

[0203] In some embodiments, the content of chloride or chlorine or a combination thereof in the bilayer after step (c) is measured by XPS, with a penetration depth of about 1 μm to 2 μm, about 1 μm to 5 μm, or about 1 μm to 10 μm. In some embodiments, the content of chloride or chlorine or a combination thereof in the lithium-filled garnet layer of the bilayer after step (c) is measured by XPS, with a penetration depth of about 1 μm to 2 μm, about 1 μm to 5 μm, or about 1 μm to 10 μm.

[0204] In some embodiments, XPS measurements show that the bilayer after step (c) contains sulfur with a penetration depth of approximately 1 μm to 20 μm. In some embodiments, XPS measurements show that the lithium-filled garnet layer in the bilayer after step (c) contains sulfur with a penetration depth of approximately 1 μm to 20 μm.

[0205] In some embodiments, XPS measurements show that the bilayer after step (c) contains sulfur with a penetration depth of approximately 1 μm to 2 μm, approximately 1 μm to 5 μm, or approximately 1 μm to 10 μm. In some embodiments, XPS measurements show that the lithium-filled garnet layer in the bilayer after step (c) contains sulfur with a penetration depth of approximately 1 μm to 2 μm, approximately 1 μm to 5 μm, or approximately 1 μm to 10 μm.

[0206] In some embodiments, XPS measurements show that the bilayer after step (c) contains boron with a penetration depth of approximately 1 μm to 20 μm. In some embodiments, XPS measurements show that the lithium-filled garnet layer in the bilayer after step (c) contains boron with a penetration depth of approximately 1 μm to 20 μm. In some embodiments, XPS measurements show that the bilayer after step (c) contains boron with a penetration depth of approximately 1 μm to 2 μm, approximately 1 μm to 5 μm, or approximately 1 μm to 10 μm. In some embodiments, XPS measurements show that the lithium-filled garnet layer in the bilayer after step (c) contains boron with a penetration depth of approximately 1 μm to 2 μm, approximately 1 μm to 5 μm, or approximately 1 μm to 10 μm. In some embodiments, XPS measurements show that the bilayer after step (c) contains zirconium with a penetration depth of approximately 1 μm to 20 μm. In some embodiments, XPS measurements show that the lithium-filled garnet layer in the bilayer after step (c) contains zirconium with a penetration depth of approximately 1 μm to 20 μm.

[0207] In some embodiments, XPS measurements show that the bilayer after step (c) contains zirconium, with a penetration depth of approximately 1 μm to 2 μm, approximately 1 μm to 5 μm, or approximately 1 μm to 10 μm. In some embodiments, XPS measurements show that the lithium-filled garnet layer in the bilayer after step (c) contains zirconium, with a penetration depth of approximately 1 μm to 2 μm, approximately 1 μm to 5 μm, or approximately 1 μm to 10 μm.

[0208] In some embodiments, XPS measurements show that the bilayer after step (c) contains fluoride or fluorine or a combination thereof, with a penetration depth of less than 1 μm. In some embodiments, XPS measurements show that the lithium-filled garnet layer in the bilayer after step (c) contains fluoride or fluorine or a combination thereof, with a penetration depth of less than 1 μm.

[0209] In some embodiments, the bilayer after step (c) is characterized in that the atomic percentage of P to Zr is approximately 1 to 15.0 as measured by XPS. In some embodiments, the bilayer after step (c) is characterized in that the atomic percentage of P to Zr is approximately 1.5 to 10 as measured by XPS. In some embodiments, the bilayer after step (c) is characterized in that the atomic percentage of P to Zr is approximately 1.5 to 5 as measured by XPS. In some embodiments, the bilayer after step (c) is characterized in that the atomic percentage of P to Zr is approximately 1.5 to 3 as measured by XPS. In some embodiments, the lithium-filled garnet layer in the bilayer after step (c) is characterized in that the atomic percentage of P to Zr is approximately 1 to 15.0 as measured by XPS. In some embodiments, the lithium-filled garnet layer in the bilayer after step (c) is characterized in that the atomic percentage of P to Zr is approximately 1.5 to 10 as measured by XPS. In some embodiments, the lithium-filled garnet layer in the bilayer after step (c) is characterized in that, as measured by XPS, the atomic percentage of P to Zr is approximately 1.5 to 5. In some embodiments, the lithium-filled garnet layer in the bilayer after step (c) is characterized in that, as measured by XPS, the atomic percentage of P to Zr is approximately 1.5 to 3.

[0210] In some embodiments, the bilayer after step (c) is characterized in that the atomic percentage of S to Zr is approximately 0 to 3, as measured by XPS. In some embodiments, the bilayer after step (c) is characterized in that the atomic percentage of S to Zr is approximately 0 to 1, as measured by XPS. In some embodiments, the lithium-filled garnet layer in the bilayer after step (c) is characterized in that the atomic percentage of S to Zr is approximately 0 to 3, as measured by XPS. In some embodiments, the bilayer after step (c) is characterized in that the atomic percentage of S to Zr is approximately 0 to 1, as measured by XPS.

[0211] In some embodiments, the bilayer after step (c) is characterized in that, as measured by XPS, the atomic percentage of functional groups CO3 to Zr is about less than 1 but greater than 0. In some embodiments, the lithium-filled garnet layer in the bilayer after step (c) is characterized in that, as measured by XPS, the atomic percentage of functional groups CO3 to Zr is about less than 1 but greater than 0.

[0212] In some embodiments, the lithium carbonate content in the bilayer after step (c) is measured by XPS to be less than about 5 atomic percent. In some embodiments, the lithium carbonate content in the lithium-filled garnet layer of the bilayer after step (c) is measured by XPS to be less than 5 atomic percent. In some embodiments, the lithium carbonate content in the bilayer after step (c) is measured by XPS to be less than 4 atomic percent. In some embodiments, the lithium carbonate content in the lithium-filled garnet layer of the bilayer after step (c) is measured by XPS to be less than 4 atomic percent. In some embodiments, the lithium carbonate content in the bilayer after step (c) is measured by XPS to be less than 3 atomic percent. In some embodiments, the lithium carbonate content in the bilayer after step (c) is measured by XPS to be less than 3 atomic percent. In some embodiments, the lithium carbonate content in the bilayer after step (c) is measured by XPS to be less than 2 atomic percent. In some embodiments, the lithium carbonate content in the bilayer after step (c) is measured by XPS to be less than 2 atomic percent. In some embodiments, the lithium carbonate content in the bilayer after step (c) is measured by XPS to be less than 1 atomic percentage. In some embodiments, the lithium carbonate content in the lithium-filled garnet layer of the bilayer after step (c) is measured by XPS to be less than 1 atomic percentage. In some embodiments, the lithium carbonate content in the bilayer after step (c) is measured by XPS to be less than 0.5 atomic percentage. In some embodiments, the lithium carbonate content in the lithium-filled garnet layer of the bilayer after step (c) is measured by XPS to be less than 0.5 atomic percentage. In some embodiments, the lithium carbonate content in the bilayer after step (c) is measured by XPS to be less than 0.5 atomic percentage. In some embodiments, the lithium carbonate content in the bilayer after step (c) is measured by XPS to be less than 0.25 atomic percentage. In some embodiments, the lithium carbonate content in the lithium-filled garnet layer of the bilayer after step (c) is measured by XPS to be less than 0.25 atomic percentage.

[0213] In some embodiments, the bilayer prior to step (b) is characterized in that, by XPS measurement, the atomic percentage of functional groups CO3 and Zr is approximately 1 to 10, and after step (c), the atomic percentage of functional groups CO3 and Zr is approximately less than 9 but greater than 0, by XPS measurement. In some embodiments, the bilayer prior to step (b) is characterized in that, by XPS measurement, the atomic percentage of functional groups CO3 and Zr is approximately 1 to 10, and after step (c), the atomic percentage of functional groups CO3 and Zr is approximately less than 5 but greater than 0, by XPS measurement. In some embodiments, the bilayer prior to step (b) is characterized in that, by XPS measurement, the atomic percentage of functional groups CO3 and Zr is approximately 1 to 10, and after step (c), the atomic percentage of functional groups CO3 and Zr is approximately less than 3 but greater than 0, by XPS measurement. In some embodiments, the bilayer prior to step (b) is characterized in that, by XPS measurement, the atomic percentage of functional groups CO3 and Zr is approximately 1 to 4, and after step (c), the atomic percentage of functional groups CO3 and Zr is approximately less than 3 but greater than 0, by XPS measurement.

[0214] In some embodiments, the bilayer after step (c) is characterized in that, as measured by XPS, the atomic percentages of functional groups CO3 and Zr are approximately less than 9 but greater than approximately 0, approximately less than 5 but greater than approximately 0, or approximately less than 3 but greater than approximately 0. In some embodiments, the bilayer after step (c) is characterized in that, as measured by XPS, the atomic percentages of functional groups CO3 and Zr are approximately less than 9 but greater than approximately 0. In some embodiments, the bilayer after step (c) is characterized in that, as measured by XPS, the atomic percentages of functional groups CO3 and Zr are approximately less than 5 but greater than approximately 0. In some embodiments, the bilayer after step (c) is characterized in that, as measured by XPS, the atomic percentages of functional groups CO3 and Zr are approximately less than 3 but greater than approximately 0.

[0215] In some embodiments, the lithium-filled garnet layer in the bilayer after step (c) is characterized in that, as measured by XPS, the atomic percentage of functional groups CO3 to Zr is less than about 9 but greater than about 0. In some embodiments, the lithium-filled garnet layer in the bilayer after step (c) is characterized in that, as measured by XPS, the atomic percentage of functional groups CO3 to Zr is less than about 5 but greater than about 0. In some embodiments, the lithium-filled garnet layer in the bilayer after step (c) is characterized in that, as measured by XPS, the atomic percentage of functional groups CO3 to Zr is less than about 3 but greater than about 0.

[0216] In some embodiments, the bilayer after step (c) is stored in dry air for up to 21 days, characterized in that, as measured by XPS, the atomic percentage of functional groups CO3 and Zr is about less than 5 but greater than 0. In some embodiments, the lithium-filled garnet layer in the bilayer after step (c) is stored in dry air for up to 21 days, characterized in that, as measured by XPS, the atomic percentage of functional groups CO3 and Zr is about less than 5 but greater than 0.

[0217] In some embodiments, after step (b), the bilayer has a lower interface resistance than before step (b).

[0218] In some embodiments, after step (c), the bilayer has a lower interface resistance than before step (b).

[0219] In some embodiments and examples, this application describes a method comprising: providing the bilayer described in this application; exposing the bilayer to environmental conditions; and measuring the ASR of the bilayer. In some examples, the measurement is performed in a drying chamber. In some examples, the measurement is performed by electrochemical impedance spectroscopy (EIS).

[0220] In some embodiments, after step (c), the ASR of the bilayer at 25°C is less than 65 Ω-cm. 2 But greater than 5 Ω-cm 2 In some embodiments, after step (c), the ASR of the bilayer at 25°C is less than 60 Ω-cm. 2 Approximately less than 55 Ω-cm 2 Approximately less than 50 Ω-cm 2 Approximately less than 45 Ω-cm 2 Approximately less than 40 Ω-cm 2 Approximately less than 35 Ω-cm 2 Approximately less than 30 Ω-cm 2 Approximately less than 25 Ω-cm 2 Approximately less than 20 Ω-cm 2Approximately less than 15 Ω-cm 2 or approximately less than 10Ω-cm 2 .

[0221] In some embodiments, measured at least approximately one month after step (c), the ASR of the bilayer at 25°C is less than approximately 65 Ω-cm. 2 But greater than 5 Ω-cm 2 In some embodiments, measured at least about one month after step (c), the ASR of the bilayer at 25°C is less than about 60 Ω-cm. 2 Approximately less than 55 Ω-cm 2 Approximately less than 50 Ω-cm 2 Approximately less than 45 Ω-cm 2 Approximately less than 40 Ω-cm 2 Approximately less than 35 Ω-cm 2 Approximately less than 30 Ω-cm 2 Approximately less than 25 Ω-cm 2 Approximately less than 20Ω-cm 2 Approximately less than 15 Ω-cm 2 Or approximately less than 10 Ω-cm 2 .

[0222] In some embodiments, measured at least approximately three months after step (c), the ASR of the bilayer at 25°C is less than approximately 65 Ω-cm. 2 But greater than 5 Ω-cm 2 In some embodiments, measured at least approximately three months after step (c), the ASR of the bilayer at 25°C is less than approximately 60 Ω-cm. 2 Approximately less than 55 Ω-cm 2 Approximately less than 50 Ω-cm 2 Approximately less than 45 Ω-cm 2 Approximately less than 40 Ω-cm 2 Approximately less than 35 Ω-cm 2 Approximately less than 30 Ω-cm 2 Approximately less than 25 Ω-cm 2 Approximately less than 20Ω-cm 2 Approximately less than 15 Ω-cm 2 Or approximately less than 10 Ω-cm 2 .

[0223] In some embodiments, measured at least approximately six months after step (c), the ASR of the bilayer at 25°C is less than approximately 65 Ω-cm. 2 But greater than 5 Ω-cm 2In some embodiments, measured at least approximately six months after step (c), the ASR of the bilayer at 25°C is less than approximately 60 Ω-cm. 2 Approximately less than 55 Ω-cm 2 Approximately less than 50 Ω-cm 2 Approximately less than 45 Ω-cm 2 Approximately less than 40 Ω-cm 2 Approximately less than 35 Ω-cm 2 Approximately less than 30 Ω-cm 2 Approximately less than 25 Ω-cm 2 Approximately less than 20Ω-cm 2 Approximately less than 15 Ω-cm 2 Or approximately less than 10 Ω-cm 2 .

[0224] In some embodiments, measured at least one year after step (c), the ASR of the bilayer at 25°C is less than 65 Ω-cm. 2 But greater than 5 Ω-cm 2 In some embodiments, measured at least about one year after step (c), the ASR of the bilayer at 25°C is less than about 60 Ω-cm. 2 Approximately less than 55 Ω-cm 2 Approximately less than 50 Ω-cm 2 Approximately less than 45 Ω-cm 2 Approximately less than 40 Ω-cm 2 Approximately less than 35 Ω-cm 2 Approximately less than 30 Ω-cm 2 Approximately less than 25 Ω-cm 2 Approximately less than 20 Ω-cm 2 Approximately less than 15 Ω-cm 2 Or approximately less than 10 Ω-cm 2 .

[0225] In some embodiments, the double layer maintains a resting voltage of 4.25V or 4.35V during a one-month high-temperature high-voltage (HTHV) test at 60°C. In some embodiments, the double layer maintains a resting voltage of 4.25V during a one-month high-temperature high-voltage (HTHV) test at 60°C. In some embodiments, the double layer maintains a resting voltage of 4.35V during a one-month high-temperature high-voltage (HTHV) test at 60°C.

[0226] In some embodiments, after a one-month high-temperature and high-pressure (HTHV) test at 60°C following step (c), the bilayer exhibits an ASR of approximately less than 65 Ω-cm at 25°C. 2But greater than 5 Ω-cm 2 In some embodiments, after a one-month high-temperature and high-pressure (HTHV) test at 60°C following step (c), the bilayer exhibits an ASR of approximately less than 60 Ω-cm at 25°C. 2 Approximately less than 55 Ω-cm 2 Approximately less than 50 Ω-cm 2 Approximately less than 45 Ω-cm 2 Approximately less than 40 Ω-cm 2 Approximately less than 35Ω-cm 2 Approximately less than 30 Ω-cm 2 Approximately less than 25 Ω-cm 2 Approximately less than 20 Ω-cm 2 Approximately less than 15 Ω-cm 2 Or approximately less than 10 Ω-cm 2 .

[0227] In some embodiments, after step (c) and following a high-temperature and high-pressure (HTHV) test at 60°C for one month, measurements are taken at least one month later, and the ASR of the bilayer at 25°C is less than 65 Ω-cm. 2 But greater than 5 Ω-cm 2 In some embodiments, after step (c) and following a high-temperature and high-pressure (HTHV) test at 60°C for one month, measurements are taken at least one month later, and the ASR of the bilayer at 25°C is less than 60 Ω-cm. 2 Approximately less than 55 Ω-cm 2 Approximately less than 50 Ω-cm 2 Approximately less than 45Ω-cm 2 Approximately less than 40 Ω-cm 2 Approximately less than 35 Ω-cm 2 Approximately less than 30 Ω-cm 2 Approximately less than 25 Ω-cm 2 Approximately less than 20Ω-cm 2 Approximately less than 15 Ω-cm 2 Or approximately less than 10 Ω-cm 2 .

[0228] In some embodiments, the ASR of the bilayer at 25°C increases by no more than approximately 10% after high-temperature high-pressure (HTHV) testing. In some embodiments, including any of the foregoing examples, the ASR of the top or bottom surface of the lithium-filled garnet film increases by no more than approximately 10% at 25°C after one month of HTHV testing at 60°C, and this low ASR persists for at least about one week, at least one month, at least two months, at least three months, at least six months, at least nine months, at least one year, or longer.

[0229] In some embodiments, after the bilayer is subjected to high temperature and high pressure (HTHV) testing at 60°C for one month, the ASR at 25°C increases by less than 10%, and this low ASR persists for at least about one week.

[0230] In some embodiments, after the bilayer is subjected to high temperature and high pressure (HTHV) testing at 60°C for one month, the ASR at 25°C increases by less than 10%, and this low ASR persists for at least one month.

[0231] In some embodiments, after the bilayer is subjected to high temperature and high pressure (HTHV) testing at 60°C for one month, the ASR at 25°C increases by less than 10%, and this low ASR persists for at least two months.

[0232] In some embodiments, after the bilayer is subjected to a high temperature and high pressure (HTHV) test at 60°C for one month, the ASR at 25°C increases by less than 10%, and this low ASR persists for at least about three months.

[0233] In some embodiments, after the bilayer is subjected to a high temperature and high pressure (HTHV) test at 60°C for one month, the ASR at 25°C increases by less than 10%, and this low ASR persists for at least about six months.

[0234] In some embodiments, after the bilayer undergoes high-temperature and high-pressure (HTHV) testing at 60°C for one month, the ASR at 25°C increases by less than approximately 15%. In some embodiments, after the bilayer undergoes high-temperature and high-pressure (HTHV) testing at 60°C for one month, the ASR at 25°C increases by less than approximately 20%, approximately 25%, approximately 30%, approximately 35%, approximately 40%, approximately 45%, approximately 50%, approximately 55%, approximately 60%, approximately 65%, or approximately 70%. In some embodiments, after the bilayer undergoes high-temperature and high-pressure (HTHV) testing at 60°C for one month, the ASR at 25°C increases by less than approximately 15%, approximately 20%, approximately 25%, approximately 30%, approximately 35%, approximately 40%, approximately 45%, approximately 50%, approximately 55%, approximately 60%, approximately 65%, or approximately 70%, and this low ASR persists for at least approximately one month, at least approximately two months, at least approximately three months, at least approximately six months, at least approximately nine months, at least approximately one year, or longer. In some embodiments, after the bilayer undergoes high-temperature high-pressure (HTHV) testing at 60°C for one month, the ASR at 25°C increases by less than 20%, and this low ASR persists for at least about one week. In some embodiments, after the bilayer undergoes high-temperature high-pressure (HTHV) testing at 60°C for one month, the ASR at 25°C increases by less than 20%, and this low ASR persists for at least about one month. In some embodiments, after the bilayer undergoes high-temperature high-pressure (HTHV) testing at 60°C for one month, the ASR at 25°C increases by less than 20%, and this low ASR persists for at least about two months. In some embodiments, after the bilayer undergoes high-temperature high-pressure (HTHV) testing at 60°C for one month, the ASR at 25°C increases by less than 20%, and this low ASR persists for at least about three months. In some embodiments, after the bilayer undergoes high-temperature high-pressure (HTHV) testing at 60°C for one month, the ASR at 25°C increases by less than 20%, and this low ASR persists for at least about six months. In some embodiments, after the bilayer undergoes high-temperature and high-pressure (HTHV) testing at 60°C for one month, the ASR at 25°C increases by less than 30%, and this low ASR persists for at least about one week. In some embodiments, after the bilayer undergoes high-temperature and high-pressure (HTHV) testing at 60°C for one month, the ASR at 25°C increases by less than 30%, and this low ASR persists for at least about one month. In some embodiments, after the bilayer undergoes high-temperature and high-pressure (HTHV) testing at 60°C for one month, the ASR at 25°C increases by less than 30%, and this low ASR persists for at least about two months. In some embodiments, after the bilayer undergoes high-temperature and high-pressure (HTHV) testing at 60°C for one month, the ASR at 25°C increases by less than 30%, and this low ASR persists for at least about three months.In some embodiments, after the bilayer undergoes high-temperature high-pressure (HTHV) testing at 60°C for one month, the ASR at 25°C increases by less than 30%, and this low ASR persists for at least approximately six months. In some embodiments, after the bilayer undergoes high-temperature high-pressure (HTHV) testing at 60°C for one month, the ASR at 25°C increases by less than 40%, and this low ASR persists for at least approximately one week. In some embodiments, after the bilayer undergoes high-temperature high-pressure (HTHV) testing at 60°C for one month, the ASR at 25°C increases by less than 40%, and this low ASR persists for at least approximately one month. In some embodiments, after the bilayer undergoes high-temperature high-pressure (HTHV) testing at 60°C for one month, the ASR at 25°C increases by less than 40%, and this low ASR persists for at least approximately two months.

[0235] In some embodiments, after the bilayer is subjected to a high temperature and high pressure (HTHV) test at 60°C for one month, the ASR at 25°C increases by less than 40%, and this low ASR persists for at least about three months.

[0236] In some embodiments, after the bilayer is subjected to a high temperature and high pressure (HTHV) test at 60°C for one month, the ASR at 25°C increases by less than 40%, and this low ASR persists for at least about six months.

[0237] In some embodiments, after the bilayer is subjected to high temperature and high pressure (HTHV) testing at 60°C for one month, the ASR at 25°C increases by less than 50%, and this low ASR persists for at least about one week.

[0238] In some embodiments, after the bilayer is subjected to high temperature and high pressure (HTHV) testing at 60°C for one month, the ASR at 25°C increases by less than 50%, and this low ASR persists for at least about one month.

[0239] In some embodiments, after the bilayer is subjected to high temperature and high pressure (HTHV) testing at 60°C for one month, the ASR at 25°C increases by less than 50%, and this low ASR persists for at least two months.

[0240] In some embodiments, after the bilayer is subjected to a high temperature and high pressure (HTHV) test at 60°C for one month, the ASR at 25°C increases by less than 50%, and this low ASR persists for at least about three months.

[0241] In some embodiments, after the bilayer undergoes high-temperature high-pressure (HTHV) testing at 60°C for one month, the ASR at 25°C increases by less than approximately 50%, and this low ASR persists for at least approximately six months. In some embodiments, after the bilayer undergoes high-temperature high-pressure (HTHV) testing at 60°C for one month, the ASR at 25°C increases by less than approximately 60%, and this low ASR persists for at least approximately one week. In some embodiments, after the bilayer undergoes high-temperature high-pressure (HTHV) testing at 60°C for one month, the ASR at 25°C increases by less than approximately 60%, and this low ASR persists for at least approximately six months. In some embodiments, after the bilayer undergoes high-temperature high-pressure (HTHV) testing at 60°C for one month, the ASR at 25°C increases by less than approximately 70%, and this low ASR persists for at least approximately one week. In some embodiments, after the bilayer undergoes high-temperature high-pressure (HTHV) testing at 60°C for one month, the ASR at 25°C increases by less than approximately 70%, and this low ASR persists for at least approximately six months. In some embodiments, the bilayer is subjected to a high temperature and high pressure (HTHV) test at 60°C for one month and then measured by XPS one week later, characterized in that the atomic percentage of functional groups CO3 and Zr is approximately less than 1 but greater than 0. Acid-treated lithium-filled garnet electrolyte

[0242] In some embodiments, this application describes a bilayer prepared by the method described in this application.

[0243] In some embodiments, this application describes a bilayer containing an acid and / or its conjugate base and / or its dissolved ions incorporated or bonded to the bilayer, wherein the acid and / or its conjugate base and / or its dissolved ions are selected from the group consisting of: (a) H3PO4 and / or H2PO4 - and / or PO4 3- and / or PO4 2- ; (b) H2SO4 and / or HSO4 - and / or SO4 2- and / or SO4 - ; (c) HCl and / or Cl - ; (d) H3BO3 and / or B(OH)4 - and / or BH2O3 - ; (e) H2TiF6 and / or TiF6 2- ; (f) H2ZrF6 and / or ZrF6 2- ;as well as (g) Their combination.

[0244] In some embodiments, the bilayer is characterized in that, by XPS measurement, the atomic percentage of S and Zr is greater than 0 but less than 4.

[0245] In certain embodiments, the bilayer is characterized in that it has a layer less than 1 μm thereon, and this layer contains lithium carbonate, lithium hydroxide, lithium oxide, their hydrates, their oxides or a combination thereof. In certain embodiments, by X-ray photoelectron spectroscopy (XPS) measurement, the lithium carbonate content of the bilayer is about less than 9 atomic percent but greater than 0. In certain embodiments, by X-ray photoelectron spectroscopy (XPS) measurement, the lithium carbonate content of the bilayer is about less than 5 atomic percent but greater than 0. In certain embodiments, by X-ray photoelectron spectroscopy (XPS) measurement, the lithium carbonate content of the bilayer is about less than 3 atomic percent but greater than 0. In certain embodiments, by X-ray photoelectron spectroscopy (XPS) measurement, the lithium carbonate content of the bilayer is about less than 1 atomic percent but greater than 0. In certain embodiments, the bilayer is sintered. In certain embodiments, the lithium-filled garnet layer in the bilayer is a lithium-filled garnet thin film. In some embodiments, the lithium-filled garnet layer in the bilayer is a sintered lithium-filled garnet thin film.

[0246] In some embodiments, including any of the foregoing embodiments, the bulk (non-surface) of the lithium-filled garnet layer conforms to the chemical formula Li A La B Al C M'' D Zr E O F , where 5 < A < 8, 1.5 < B < 4, 0.1 < C < 2, 0 ≤ D < 2, 1 < E < 3, 10 < F < 13, and M'' is selected from: Mo, W, Nb, Y, Ta, Ga, Sb, Ca, Ba, Sr, Ce, Hf, and Rb.

[0247] In some embodiments, including any of the foregoing embodiments, the bulk (non-surface) of the lithium-filled garnet layer conforms to the chemical formula Li x La3Zr2O 12 + yAl2O3, where x is from 5.8 to 7.0 and y is 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 1.0.

[0248] In some embodiments, including any of the foregoing embodiments, the bulk (non-surface) of the lithium-filled garnet layer conforms to the chemical formula Li a La b Zr c O d Al e ​, where 5 ≤ a ≤ 8, 2 ≤ b ≤ 4, 1 ≤ c ≤ 2, 11 ≤ d ≤ 14, 0 ≤ e ≤ 1, and the chemical formula Li is made electrically neutral by selecting a, b, c, d, and e among them. In some embodiments, including any of the foregoing embodiments, a is 6, 6.25, 6.50, 6.75, or 7. In some embodiments, including any of the foregoing embodiments, e is 0, 0.25, 0.5, 0.75, or 1. In some embodiments, including any of the foregoing embodiments, b is 3 and z is 2. In some embodiments, including any of the foregoing embodiments, d is 12. In some embodiments, including any of the foregoing embodiments, a is 6.25, b is 3, c is 2, d is 12, and e is 0.25. In some embodiments, including any of the foregoing embodiments, a is approximately 6.25, b is approximately 3, c is approximately 2, d is approximately 12, and e is approximately 0.25. a La b Zr c O d Al e is electrically neutral. In some embodiments, including any of the foregoing embodiments, the bulk (non-surface) of the lithium-filled garnet layer conforms to a chemical formula selected from the group consisting of: Li

[0249] In some embodiments, including any of the foregoing embodiments, the bulk (non-surface) of the lithium-filled garnet layer conforms to a chemical formula selected from the group consisting of: Li A La B M' C M'' D Zr E O F , Li A La B M' C M'' D Ta E O F and Li A La B M' C M'' D Nb E O F , where 4 < A < 8.5, 1.5 < B < 4, 0 ≤ C < 2, 0 ≤ D < 2, 0 < E < 2, 10 < F < 14, where M' and M'' are each independently selected from the group consisting of: Al, Mo, W, Nb, Sb, Ca, Ba, Sr, Ce, Hf, Rb, and Ta. In some examples, M' and M'' are the same members selected from the group consisting of: Al, Mo, W, Nb, Sb, Ca, Ba, Sr, Ce, Hf, Rb, and Ta. However, unless there is a clear contrary indication, M' and M'' are not the same element.

[0250] In some embodiments, including any of the foregoing embodiments, the bulk (non-surface) of the lithium-filled garnet layer conforms to a chemical formula selected from the group consisting of: Li A La B M' CM'' D Zr E O F 、Li A La B M' C M'' D Ta E O F 和Li A La B M' C M'' D Nb E O F where 4 < A < 8.5, 1.5 < B < 4, 0 ≤ C < 2.5, 0 ≤ D < 2.5, 0 < E < 2.5, 10 < F < 14, where M' and M'' are each independently selected from the group consisting of: Al, Mo, W, Nb, Ga, Y, Gd, Sb, Ca, Ba, Sr, Ce, Hf, Rb, and Ta.

[0251] In some embodiments, including any of the foregoing embodiments, the bulk (non-surface) of the lithium-filled garnet layer conforms to the chemical formula Li a La b Zr c Al d Me'' e O f where 5 < a < 7.7, 2 < b < 4, 0 < c < 2.5, 0 < d < 2.5, 0 ≤ e < 2.5, 10 < f < 14, and where Me'' is a metal selected from Nb, Ta, V, W, Mo, and Sb.

[0252] In some embodiments, including any of the foregoing embodiments, the bulk (non-surface) of the lithium-filled garnet layer conforms to the chemical formula Li a La b Zr c Al d O f where 5 < a < 7.7, 2 < b < 4, 0 < c < 2.5, 0 < d < 2.5, 10 < f < 14.

[0253] In some embodiments, including any of the foregoing embodiments, the bulk (non-surface) of the lithium-filled garnet layer conforms to the chemical formula Li a La b Zr c Al d [[ID=​​​​

[0254] In some embodiments, including any of the foregoing embodiments, the bulk (non-surface) phase of the lithium-filled garnet layer conforms to the chemical formula Li. a La b Zr c Al d O f , of which 5 <a<7.7、2<b<4、0<c<2.5、0<d<2、10<f<14。

[0255] In some embodiments, including any of the foregoing embodiments, the bulk (non-surface) phase of the lithium-filled garnet layer conforms to the chemical formula Li. x La3Zr2O 12 0.35Al2O3, of which 4 <x<8.5。

[0256] In some embodiments, including any of the foregoing embodiments, the bulk (non-surface) phase of the lithium-filled garnet layer conforms to the chemical formula Li. x La3Zr2O 12 0.5Al2O3, of which 4 <x<8.5。

[0257] In some embodiments, including any of the foregoing embodiments, the bulk (non-surface) phase of the lithium-filled garnet layer conforms to the chemical formula Li. x La3Zr2O 12 0.65Al2O3, of which 4 <x<8.5。

[0258] In some embodiments, including any of the foregoing embodiments, the bulk (non-surface) phase of the lithium-filled garnet layer conforms to the chemical formula Li. x La3Zr2O 12 ·Al2O3, of which 4 <x<8.5。

[0259] In some embodiments, including any of the foregoing examples, the bulk (non-surface) phase of the lithium-filled garnet layer approximately conforms to Li6La3Zr2O. 12 Al 1 / 3 Approximately conforms to Li 6.25 La3Zr2O 12 Al 0.25 Approximately conforms to Li4La3Zr2O 12 Al1; approximately conforms to Li 6.7 La3Zr2O 12 Al 0.3 Or approximately conforming to Li7La3Zr2O 12 .

[0260] In some embodiments, including any of the foregoing embodiments, the bulk phase (non-surface) of the lithium-filled garnet layer is polycrystalline.

[0261] In some embodiments, the bilayer contains H3PO4 and / or its conjugate base H2PO4 incorporated or bonded to the bilayer. - and / or its ions PO4 3- and / or PO4 2- In some embodiments, the bilayer contains H3PO4 and / or its conjugate base H2PO4 incorporated or bonded to the surface of the lithium-filled garnet layer in the bilayer. - and / or its ions PO4 3- and / or PO4 2- .

[0262] In some embodiments, the bilayer contains H2TiF6 and / or its ionic TiF6 incorporated or bonded to the bilayer. 2- In some embodiments, the bilayer contains H2TiF6 and / or its ionic TiF6 incorporated or bonded to the surface of the lithium-filled garnet layer in the bilayer. 2- .

[0263] In some embodiments, the bilayer contains HCl and / or its conjugate base Cl incorporated or bonded to the bilayer. - In some embodiments, the bilayer contains HCl and / or its conjugate base Cl doped or bonded to the surface of the lithium-filled garnet layer in the bilayer. - .

[0264] In some embodiments, the bilayer contains H2SO4 and / or its conjugate base HSO4 incorporated or bonded to the bilayer. - and / or its ions SO4 2- and / or SO4 - In some embodiments, the bilayer contains H₂SO₄ and / or its conjugate base HSO₄ incorporated or bonded to the surface of the lithium-filled garnet layer in the bilayer. - and / or its ions SO4 2- and / or SO4 - .

[0265] In some embodiments, the bilayer contains H3BO3 and / or its conjugate base B(OH)4 incorporated or bonded to the bilayer. - and / or its ions BH2O3 - In some embodiments, the bilayer contains H3BO3 and / or its conjugate base B(OH)4 incorporated or bonded to the surface of the lithium-filled garnet layer in the bilayer. - and / or its ions BH2O3 - .

[0266] In some embodiments, the bilayer contains H2ZrF6 and / or its ionic ZrF6 incorporated or bonded to the bilayer.2- In some embodiments, the bilayer contains H2ZrF6 and / or its ionic ZrF6 incorporated or bonded to the surface of the lithium-filled garnet layer in the bilayer. 2- .

[0267] In some embodiments, the bilayer includes a phosphorus-containing layer containing Li3PO4, LiH2PO4, Li2HPO4, Li(CH3)2PO4 (i.e., lithium dimethyl phosphate), Li2(CH3)PO4 (i.e., dilithium methyl phosphate), Li4P2O7, or combinations thereof. In some embodiments, the lithium-filled garnet layer in the bilayer after step (c) includes a phosphorus-containing layer containing Li3PO4, LiH2PO4, Li2HPO4, Li(CH3)2PO4, Li2(CH3)PO4, Li4P2O7, or combinations thereof.

[0268] In some embodiments, the bilayer contains Li3PO4. In some embodiments, the bilayer contains LiH2PO4. In some embodiments, the bilayer contains Li2HPO4. In some embodiments, the bilayer contains Li(CH3)2PO4. In some embodiments, the bilayer contains Li2(CH3)PO4. In some embodiments, the lithium-filled garnet layer in the bilayer contains Li3PO4. In some embodiments, the lithium-filled garnet layer in the bilayer contains LiH2PO4. In some embodiments, the lithium-filled garnet layer in the bilayer contains Li2HPO4. In some embodiments, the lithium-filled garnet layer in the bilayer contains Li(CH3)2PO4. In some embodiments, the lithium-filled garnet layer in the bilayer contains Li2(CH3)PO4.

[0269] In some embodiments, the bilayer includes a partially phosphorus-containing layer containing Li3PO4, LiH2PO4, Li2HPO4, Li(CH3)2PO4, Li2(CH3)PO4, Li4P2O7, or a combination thereof. In some embodiments, the lithium-filled garnet layer in the bilayer includes a partially phosphorus-containing layer containing Li3PO4, LiH2PO4, Li2HPO4, Li(CH3)2PO4, Li2(CH3)PO4, Li4P2O7, or a combination thereof.

[0270] In some embodiments, the bilayer includes a continuous phosphorus-containing layer containing Li3PO4, LiH2PO4, Li2HPO4, Li(CH3)2PO4, Li2(CH3)PO4, Li4P2O7, or combinations thereof. In some embodiments, the lithium-filled garnet layer in the bilayer includes a continuous phosphorus-containing layer containing Li3PO4, LiH2PO4, Li2HPO4, Li(CH3)2PO4, Li2(CH3)PO4, Li4P2O7, or combinations thereof.

[0271] In some embodiments, the bilayer includes a discontinuous phosphorus-containing layer containing Li3PO4, LiH2PO4, Li2HPO4, Li(CH3)2PO4, Li2(CH3)PO4, Li4P2O7, or combinations thereof. In some embodiments, the lithium-filled garnet layer in the bilayer includes a discontinuous phosphorus-containing layer containing Li3PO4, LiH2PO4, Li2HPO4, Li(CH3)2PO4, Li2(CH3)PO4, Li4P2O7, or combinations thereof.

[0272] In some embodiments, the bilayer contains members selected from the group consisting of phosphorus, titanium, chloride, chlorine, sulfur, boron, zirconium, and combinations thereof, with a content greater than about 0.05 atomic percent as measured by X-ray photoelectron spectroscopy (XPS). In some embodiments, the lithium-filled garnet layer in the bilayer contains members selected from the group consisting of phosphorus, titanium, chloride, chlorine, sulfur, boron, zirconium, and combinations thereof, with a content greater than about 0.05 atomic percent as measured by X-ray photoelectron spectroscopy (XPS).

[0273] In some embodiments, the bilayer contains members selected from the group consisting of phosphorus, titanium, chloride, chlorine, sulfur, boron, zirconium, and combinations thereof, with a content greater than about 0.1 atomic percent or greater than about 0.2 atomic percent as measured by XPS. In some embodiments, the lithium-filled garnet layer in the bilayer contains members selected from the group consisting of phosphorus, titanium, chloride, chlorine, sulfur, boron, zirconium, and combinations thereof, with a content greater than about 0.1 atomic percent or greater than about 0.2 atomic percent as measured by XPS.

[0274] In some embodiments, the bilayer contains phosphorus, the content of which, as measured by XPS, is greater than about 0.05 atomic percent, greater than about 0.1 atomic percent, or greater than about 0.2 atomic percent. In some embodiments, the lithium-filled garnet layer in the bilayer contains phosphorus, the content of which, as measured by XPS, is greater than about 0.05 atomic percent, greater than about 0.1 atomic percent, or greater than about 0.2 atomic percent.

[0275] In some embodiments, the bilayer contains titanium, the content of which, as measured by XPS, is greater than about 0.05 atomic percent, greater than about 0.1 atomic percent, or greater than about 0.2 atomic percent. In some embodiments, the lithium-filled garnet layer in the bilayer contains titanium, the content of which, as measured by XPS, is greater than about 0.05 atomic percent, greater than about 0.1 atomic percent, or greater than about 0.2 atomic percent.

[0276] In some embodiments, the bilayer contains chloride or chlorine or a combination thereof, the content of which, as measured by XPS, is greater than about 0.05 atomic percent, greater than about 0.1 atomic percent, or greater than about 0.2 atomic percent. In some embodiments, the lithium-filled garnet layer in the bilayer contains chloride or chlorine or a combination thereof, the content of which, as measured by XPS, is greater than about 0.05 atomic percent, greater than about 0.1 atomic percent, or greater than about 0.2 atomic percent.

[0277] In some embodiments, the bilayer contains sulfur, the content of which, as measured by XPS, is greater than about 0.05 atomic percent, greater than about 0.1 atomic percent, or greater than about 0.2 atomic percent. In some embodiments, the lithium-filled garnet layer in the bilayer contains sulfur, the content of which, as measured by XPS, is greater than about 0.05 atomic percent, greater than about 0.1 atomic percent, or greater than about 0.2 atomic percent.

[0278] In some embodiments, the bilayer contains boron, and its content, as measured by XPS, is greater than about 0.05 atomic percent, greater than about 0.1 atomic percent, or greater than about 0.2 atomic percent. In some embodiments, the lithium-filled garnet layer in the bilayer contains boron, and its content, as measured by XPS, is greater than about 0.05 atomic percent, greater than about 0.1 atomic percent, or greater than about 0.2 atomic percent.

[0279] In some embodiments, the bilayer contains zirconium, the content of which, as measured by XPS, is greater than about 0.05 atomic percent, greater than about 0.1 atomic percent, or greater than about 0.2 atomic percent. In some embodiments, the lithium-filled garnet layer in the bilayer contains zirconium, the content of which, as measured by XPS, is greater than about 0.05 atomic percent, greater than about 0.1 atomic percent, or greater than about 0.2 atomic percent.

[0280] In some embodiments, the bilayer contains members selected from the group consisting of phosphorus, titanium, chloride, chlorine, sulfur, boron, zirconium, and combinations thereof, and its penetration depth, as measured by XPS, is approximately 1 μm to 20 μm. In some embodiments, the lithium-filled garnet layer in the bilayer contains members selected from the group consisting of phosphorus, titanium, chloride, chlorine, sulfur, boron, zirconium, and combinations thereof, and its penetration depth, as measured by XPS, is approximately 1 μm to 20 μm.

[0281] In some embodiments, the bilayer contains members selected from the group consisting of phosphorus, titanium, chloride, chlorine, sulfur, boron, zirconium, and combinations thereof, and its penetration depth is measured to be approximately 1 μm to 2 μm by XPS. In some embodiments, the lithium-filled garnet layer in the bilayer contains members selected from the group consisting of phosphorus, titanium, chloride, chlorine, sulfur, boron, zirconium, and combinations thereof, and its penetration depth is measured to be approximately 1 μm to 2 μm by XPS.

[0282] In some embodiments, the bilayer contains members selected from the group consisting of phosphorus, titanium, chloride, chlorine, sulfur, boron, zirconium, and combinations thereof, and its penetration depth, as measured by XPS, is approximately 1 μm to 5 μm. In some embodiments, the lithium-filled garnet layer in the bilayer contains members selected from the group consisting of phosphorus, titanium, chloride, chlorine, sulfur, boron, zirconium, and combinations thereof, and its penetration depth, as measured by XPS, is approximately 1 μm to 5 μm.

[0283] In some embodiments, the bilayer contains members selected from the group consisting of phosphorus, titanium, chloride, chlorine, sulfur, boron, zirconium, and combinations thereof, and its penetration depth is measured to be approximately 5 μm to 10 μm by XPS. In some embodiments, the lithium-filled garnet layer in the bilayer contains members selected from the group consisting of phosphorus, titanium, chloride, chlorine, sulfur, boron, zirconium, and combinations thereof, and its penetration depth is measured to be approximately 5 μm to 10 μm by XPS.

[0284] In some embodiments, the bilayer contains members selected from the group consisting of phosphorus, titanium, chloride, chlorine, sulfur, boron, zirconium, and combinations thereof, and its penetration depth is measured to be approximately 10 μm to 15 μm by XPS. In some embodiments, the lithium-filled garnet layer in the bilayer contains members selected from the group consisting of phosphorus, titanium, chloride, chlorine, sulfur, boron, zirconium, and combinations thereof, and its penetration depth is measured to be approximately 10 μm to 15 μm by XPS.

[0285] In some embodiments, the bilayer contains members selected from the group consisting of phosphorus, titanium, chloride, chlorine, sulfur, boron, zirconium, and combinations thereof, and its penetration depth is measured to be approximately 15 μm to 20 μm by XPS. In some embodiments, the lithium-filled garnet layer in the bilayer contains members selected from the group consisting of phosphorus, titanium, chloride, chlorine, sulfur, boron, zirconium, and combinations thereof, and its penetration depth is measured to be approximately 15 μm to 20 μm by XPS.

[0286] In some embodiments, the bilayer contains phosphorus, and its penetration depth, measured by XPS, is approximately 1 μm to 20 μm. In some embodiments, the lithium-filled garnet layer in the bilayer contains phosphorus, and its penetration depth, measured by XPS, is approximately 1 μm to 20 μm.

[0287] In some embodiments, the bilayer contains phosphorus, and its penetration depth, as measured by XPS, is approximately 1 μm to 2 μm, approximately 1 μm to 5 μm, or approximately 1 μm to 10 μm. In some embodiments, the lithium-filled garnet layer in the bilayer contains phosphorus, and its penetration depth, as measured by XPS, is approximately 1 μm to 2 μm, approximately 1 μm to 5 μm, or approximately 1 μm to 10 μm.

[0288] In some embodiments, the bilayer contains titanium, and its penetration depth, measured by XPS, is approximately 1 μm to 20 μm. In some embodiments, the lithium-filled garnet layer in the bilayer contains titanium, and its penetration depth, measured by XPS, is approximately 1 μm to 20 μm.

[0289] In some embodiments, the bilayer contains titanium, and its penetration depth, measured by XPS, is approximately 1 μm to 2 μm, approximately 1 μm to 5 μm, or approximately 1 μm to 10 μm. In some embodiments, the lithium-filled garnet layer in the bilayer contains titanium, and its penetration depth, measured by XPS, is approximately 1 μm to 2 μm, approximately 1 μm to 5 μm, or approximately 1 μm to 10 μm.

[0290] In some embodiments, the bilayer contains chloride or chlorine or a combination thereof, and its penetration depth, measured by XPS, is approximately 1 μm to 20 μm. In some embodiments, the lithium-filled garnet layer in the bilayer contains chloride or chlorine or a combination thereof, and its penetration depth, measured by XPS, is approximately 1 μm to 20 μm.

[0291] In some embodiments, the bilayer contains chloride or chlorine or a combination thereof, and its penetration depth, as measured by XPS, is approximately 1 μm to 2 μm, approximately 1 μm to 5 μm, or approximately 1 μm to 10 μm. In some embodiments, the lithium-filled garnet layer in the bilayer contains chloride or chlorine or a combination thereof, and its penetration depth, as measured by XPS, is approximately 1 μm to 2 μm, approximately 1 μm to 5 μm, or approximately 1 μm to 10 μm.

[0292] In some embodiments, the bilayer contains sulfur, and its penetration depth, measured by X-ray photoelectron spectroscopy, is approximately 1 μm to 20 μm. In some embodiments, the lithium-filled garnet layer in the bilayer contains sulfur, and its penetration depth, measured by X-ray photoelectron spectroscopy, is approximately 1 μm to 20 μm.

[0293] In some embodiments, the bilayer contains sulfur, and its penetration depth, as measured by XPS, is approximately 1 μm to 2 μm, approximately 1 μm to 5 μm, or approximately 1 μm to 10 μm. In some embodiments, the lithium-filled garnet layer in the bilayer contains sulfur, and its penetration depth, as measured by XPS, is approximately 1 μm to 2 μm, approximately 1 μm to 5 μm, or approximately 1 μm to 10 μm.

[0294] In some embodiments, the bilayer contains boron, and its penetration depth, measured by XPS, is approximately 1 μm to 20 μm. In some embodiments, the lithium-filled garnet layer in the bilayer contains boron, and its penetration depth, measured by XPS, is approximately 1 μm to 20 μm.

[0295] In some embodiments, the bilayer contains boron, and its penetration depth, measured by XPS, is approximately 1 μm to 2 μm, approximately 1 μm to 5 μm, or approximately 1 μm to 10 μm. In some embodiments, the lithium-filled garnet layer in the bilayer contains boron, and its penetration depth, measured by XPS, is approximately 1 μm to 2 μm, approximately 1 μm to 5 μm, or approximately 1 μm to 10 μm.

[0296] In some embodiments, the bilayer contains zirconium, and its penetration depth, measured by XPS, is approximately 1 μm to 20 μm. In some embodiments, the lithium-filled garnet layer in the bilayer contains zirconium, and its penetration depth, measured by XPS, is approximately 1 μm to 20 μm.

[0297] In some embodiments, the bilayer contains zirconium, and its penetration depth, as measured by XPS, is approximately 1 μm to 2 μm, approximately 1 μm to 5 μm, or approximately 1 μm to 10 μm. In some embodiments, the lithium-filled garnet layer in the bilayer contains zirconium, and its penetration depth, as measured by XPS, is approximately 1 μm to 2 μm, approximately 1 μm to 5 μm, or approximately 1 μm to 10 μm.

[0298] In some embodiments, the bilayer contains fluoride or fluorine or a combination thereof, and its penetration depth is less than 1 μm as measured by XPS. In some embodiments, the lithium-filled garnet layer in the bilayer contains fluoride or fluorine or a combination thereof, and its penetration depth is less than 1 μm as measured by XPS.

[0299] In some embodiments, the lithium carbonate content in the bilayer is measured by XPS to be less than 5 atomic percent. In some embodiments, the lithium carbonate content in the lithium-filled garnet layer of the bilayer is measured by XPS to be less than 5 atomic percent. In some embodiments, the lithium carbonate content in the bilayer is measured by XPS to be less than 3 atomic percent. In some embodiments, the lithium carbonate content in the lithium-filled garnet layer of the bilayer is measured by XPS to be less than 3 atomic percent. In some embodiments, the lithium carbonate content in the bilayer is measured by XPS to be less than 1 atomic percent. In some embodiments, the lithium carbonate content in the lithium-filled garnet layer of the bilayer is measured by XPS to be less than 1 atomic percent. In some embodiments, the lithium carbonate content in the bilayer is measured by XPS to be less than 1 atomic percent. In some embodiments, the lithium carbonate content in the bilayer is measured by XPS to be less than 0.5 atomic percent. In some embodiments, the lithium carbonate content in the lithium-filled garnet layer of the bilayer is measured by XPS to be less than 0.5 atomic percent. In some embodiments, the lithium carbonate content in the bilayer is measured by XPS to be less than 0.5 atomic percent. In some embodiments, the lithium carbonate content in the bilayer is measured by XPS to be less than 0.25 atomic percent. In some embodiments, the lithium carbonate content in the lithium-filled garnet layer of the bilayer is measured by XPS to be less than 0.25 atomic percent.

[0300] In some embodiments, the bilayer after step (c) is characterized in that the atomic percentage of P to Zr is approximately 1 to 15.0 as measured by XPS. In some embodiments, the bilayer is characterized in that the atomic percentage of P to Zr is approximately 1.5 to 10 as measured by XPS. In some embodiments, the bilayer is characterized in that the atomic percentage of P to Zr is approximately 1.5 to 5 as measured by XPS. In some embodiments, the bilayer is characterized in that the atomic percentage of P to Zr is approximately 1.5 to 3 as measured by XPS. In some embodiments, the lithium-filled garnet layer in the bilayer is characterized in that the atomic percentage of P to Zr is approximately 1 to 15.0 as measured by XPS. In some embodiments, the lithium-filled garnet layer in the bilayer is characterized in that the atomic percentage of P to Zr is approximately 1.5 to 10 as measured by XPS. In some embodiments, the lithium-filled garnet layer in the bilayer is characterized in that the atomic percentage of P to Zr is approximately 1.5 to 5 as measured by XPS. In some embodiments, the lithium-filled garnet layer in the bilayer is characterized in that, as measured by XPS, the atomic percentage of P to Zr is approximately 1.5 to 3.

[0301] In some embodiments, the bilayer is characterized in that the atomic percentages of S and Zr, as measured by XPS, are approximately 0 to 3. In some embodiments, the bilayer is characterized in that the atomic percentages of S and Zr, as measured by XPS, are approximately 0 to 1.

[0302] In some embodiments, the bilayer is characterized in that, as measured by XPS, the atomic percentage of functional groups CO3 and Zr is approximately less than 1 but greater than 0.

[0303] In some embodiments, the ASR of the bilayer at 25°C is approximately less than 65 Ω-cm. 2 But greater than 5 Ω-cm 2 In some embodiments, the ASR of the bilayer at 25°C is less than 60 Ω-cm. 2 But greater than 5 Ω-cm 2 In some embodiments, the ASR of the bilayer at 25°C is less than 55 Ω-cm. 2 But greater than 5 Ω-cm 2 In some embodiments, the ASR of the bilayer at 25°C is less than 50 Ω-cm. 2 But greater than 5 Ω-cm 2 In some embodiments, the ASR of the bilayer at 25°C is less than 45 Ω-cm. 2 But greater than 5 Ω-cm 2 In some embodiments, the ASR of the bilayer at 25°C is less than 40 Ω-cm. 2 But greater than 5 Ω-cm 2 In some embodiments, the ASR of the bilayer at 25°C is less than 35 Ω-cm. 2 But greater than 5Ω-cm 2 In some embodiments, the ASR of the bilayer at 25°C is less than 30 Ω-cm. 2 But greater than 5 Ω-cm 2 In some embodiments, the ASR of the bilayer at 25°C is less than 25 Ω-cm. 2 But greater than 5 Ω-cm 2 In some embodiments, the ASR of the bilayer at 25°C is less than 20 Ω-cm. 2 But greater than 5 Ω-cm 2 In some embodiments, the ASR of the bilayer at 25°C is less than 15 Ω-cm. 2 But greater than 5 Ω-cm 2 In some embodiments, the ASR of the bilayer at 25°C is less than 10 Ω-cm. 2 But greater than 5 Ω-cm 2 .

[0304] In some embodiments, the double layer maintains a resting voltage of 4.25V or 4.35V during a one-month high-temperature high-voltage (HTHV) test at 60°C. In some embodiments, the double layer maintains a resting voltage of 4.25V during a one-month high-temperature high-voltage (HTHV) test at 60°C. In some embodiments, the double layer maintains a resting voltage of 4.35V during a one-month high-temperature high-voltage (HTHV) test at 60°C.

[0305] In some embodiments, after one month of high-temperature and high-pressure (HTHV) testing at 60°C, the bilayer exhibits an ASR of approximately less than 65 Ω-cm at 25°C. 2 But greater than 5 Ω-cm 2 In some embodiments, after one month of HTHV testing at 60°C, the bilayer exhibits an ASR of approximately less than 60 Ω-cm at 25°C. 2 But greater than 5 Ω-cm 2 In some embodiments, after one month of HTHV testing at 60°C, the bilayer exhibits an ASR of approximately less than 55 Ω-cm at 25°C. 2 But greater than 5 Ω-cm 2 In some embodiments, after one month of HTHV testing at 60°C, the bilayer exhibits an ASR of approximately less than 50 Ω-cm at 25°C. 2 But greater than 5 Ω-cm 2 In some embodiments, after one month of HTHV testing at 60°C, the bilayer exhibits an ASR of approximately less than 45 Ω-cm at 25°C. 2 But greater than 5 Ω-cm 2 In some embodiments, after one month of HTHV testing at 60°C, the bilayer exhibits an ASR of approximately less than 40 Ω-cm at 25°C. 2 But greater than 5 Ω-cm 2 In some embodiments, after one month of HTHV testing at 60°C, the bilayer exhibits an ASR of approximately less than 35 Ω-cm at 25°C. 2 But greater than 5 Ω-cm 2 In some embodiments, after one month of HTHV testing at 60°C, the bilayer exhibits an ASR of approximately less than 30 Ω-cm at 25°C. 2 But greater than 5Ω-cm 2 In some embodiments, after one month of HTHV testing at 60°C, the bilayer exhibits an ASR of approximately less than 25 Ω-cm at 25°C. 2 But greater than 5 Ω-cm 2 In some embodiments, after HTHV testing at 60°C for one month, the bilayer exhibits an ASR of approximately less than 20 Ω-cm at 25°C.2 But greater than 5 Ω-cm 2 In some embodiments, after one month of HTHV testing at 60°C, the bilayer exhibits an ASR of approximately less than 15 Ω-cm at 25°C. 2 But greater than 5 Ω-cm 2 In some embodiments, after one month of HTHV testing at 60°C, the bilayer exhibits an ASR of approximately less than 10 Ω-cm at 25°C. 2 But greater than 5 Ω-cm 2 In some embodiments, after the bilayer undergoes high-temperature and high-pressure (HTHV) testing at 60°C for one month, the ASR at 25°C increases by less than 10%. In some embodiments, after the bilayer undergoes HTHV testing at 60°C for one month, the ASR at 25°C increases by no more than about 10%. In some embodiments, after the bilayer undergoes HTHV testing at 60°C for one month, the ASR at 25°C increases by no more than about 15%. In some embodiments, after the bilayer undergoes HTHV testing at 60°C for one month, the ASR at 25°C increases by no more than about 20%.

[0306] In some embodiments, including any of the foregoing examples, the ASR of the top and / or bottom surfaces of the lithium-filled garnet film increases by no more than about 25% at 25°C after one month of high-temperature and high-pressure (HTHV) testing at 60°C. In some embodiments, the ASR of the bilayer increases by no more than about 30% at 25°C after one month of HTHV testing at 60°C. In some embodiments, the ASR of the bilayer increases by no more than about 35% at 25°C after one month of HTHV testing at 60°C. In some embodiments, the ASR of the bilayer increases by no more than about 40% at 25°C after one month of HTHV testing at 60°C. In some embodiments, the ASR of the bilayer increases by no more than about 45% at 25°C after one month of HTHV testing at 60°C. In some embodiments, the ASR of the bilayer increases by no more than about 50% at 25°C after one month of HTHV testing at 60°C. In some embodiments, after the bilayer is tested for HTHV at 60°C for one month, the ASR at 25°C increases by no more than about 60%. In some embodiments, after the bilayer is tested for HTHV at 60°C for one month, the ASR at 25°C increases by no more than about 65%. In some embodiments, after the bilayer is tested for HTHV at 60°C for one month, the ASR at 25°C increases by no more than about 70%.

[0307] In some embodiments, including any of the foregoing embodiments, the low ASR lasts for at least about one month, at least about two months, at least about three months, at least about four months, at least about six months, at least about nine months, at least about one year, or longer.

[0308] In some embodiments, including any of the foregoing embodiments, the double-layered ASR is at least 10 mm 2 The surface area variation does not exceed 10%.

[0309] In some embodiments, including any of the foregoing embodiments, the ASR of the dual-layer changes by no more than 10% over time for at least one day.

[0310] In some embodiments, including any of the foregoing embodiments, the ASR of the dual-layer changes by no more than 10% over time for at least one month.

[0311] In some embodiments, including any of the foregoing embodiments, the ASR of the dual-layer changes by no more than 10% over time for at least six months.

[0312] In some embodiments, including any of the foregoing embodiments, the ASR of the dual-layer changes by no more than 10% over time for at least one year.

[0313] In some embodiments, including any of the foregoing embodiments, the ASR of the bilayer increases by no more than 10% after exposure to environmental conditions.

[0314] In some embodiments, including any of the foregoing embodiments, the double-layered ASR is at least 10 mm 2 The surface area variation does not exceed 20%.

[0315] In some embodiments, including any of the foregoing embodiments, the ASR of the dual-layer changes by no more than 20% over time for at least one day.

[0316] In some embodiments, including any of the foregoing embodiments, the ASR of the dual-layer changes by no more than 20% over time for at least one month.

[0317] In some embodiments, including any of the foregoing embodiments, the ASR of the dual-layer changes by no more than 20% over time for at least six months.

[0318] In some embodiments, including any of the foregoing embodiments, the ASR of the dual-layer changes by no more than 20% over time for at least one year.

[0319] In some embodiments, including any of the foregoing embodiments, the ASR of the bilayer increases by no more than 20% after exposure to environmental conditions.

[0320] In some embodiments, including any of the foregoing embodiments, the double-layered ASR is at least 10 mm 2 The surface area variation does not exceed 30%. In some embodiments, including any of the foregoing examples, the ASR of the bilayer changes by a function of no more than 30% over time for at least one year. In some embodiments, including any of the foregoing examples, the ASR of the bilayer increases by no more than 30% after exposure to environmental conditions. In some embodiments, including any of the foregoing examples, the ASR of the bilayer is at least 10 mm. 2 The surface area variation does not exceed 40%. In some embodiments, including any of the foregoing examples, the ASR of the bilayer changes by a function of no more than 40% over time for at least one year. In some embodiments, including any of the foregoing examples, the ASR of the bilayer increases by no more than 40% after exposure to environmental conditions. In some embodiments, including any of the foregoing examples, the ASR of the bilayer is at least 10 mm. 2 The surface area variation does not exceed 50%. In some embodiments, including any of the foregoing examples, the ASR of the bilayer changes by a function of no more than 50% over time for at least one year. In some embodiments, including any of the foregoing examples, the ASR of the bilayer increases by no more than 50% after exposure to environmental conditions. In some embodiments, including any of the foregoing examples, the ASR of the bilayer is at least 10 mm. 2 The surface area variation does not exceed 60%. In some embodiments, including any of the foregoing examples, the ASR of the bilayer changes by a function of no more than 60% over time for at least one year. In some embodiments, including any of the foregoing examples, the ASR of the bilayer increases by no more than 60% after exposure to environmental conditions. In some embodiments, including any of the foregoing examples, the ASR of the bilayer is at least 10 mm. 2 The surface area variation does not exceed 70%. In some embodiments, including any of the foregoing examples, the ASR of the bilayer changes by a function of no more than 70% over time for at least one year. In some embodiments, including any of the foregoing examples, the ASR of the bilayer increases by no more than 70% after exposure to environmental conditions.

[0321] In some embodiments, the bilayer is subjected to a high temperature and high pressure (HTHV) test at 60°C for one month and then measured by XPS one week later, characterized in that the atomic percentage of functional groups CO3 and Zr is approximately less than 1 but greater than 0.

[0322] In some embodiments, the lithium carbonate thickness on the surface of the bilayer before acid treatment is approximately 1 nm to 500 nm. In some embodiments, the lithium carbonate thickness on the surface of the lithium-filled garnet layer in the bilayer before acid treatment is approximately 1 nm to 500 nm.

[0323] In some embodiments, the lithium carbonate thickness on the surface of the bilayer after acid treatment is approximately 1 nm to 50 nm. In some embodiments, the lithium carbonate thickness on the surface of the lithium-filled garnet layer in the bilayer after acid treatment is approximately 1 nm to 50 nm. Equipment and vehicles

[0324] This application also provides an electrochemical device comprising the double layer described herein. In one embodiment, the electrochemical device is an electrochemical battery. In another embodiment, the electrochemical device is a rechargeable battery.

[0325] This application also provides an electric vehicle that includes an electrochemical device or a rechargeable battery, said electrochemical device or rechargeable battery comprising the double layer described in this application. Continuous double-layer processing production line

[0326] In one aspect, this application describes a continuous double-layer processing production line, comprising: a front roller wound with a double layer, the double layer comprising a metal foil or metal powder layer and a lithium-filled garnet layer; the metal layer being in contact with the front roller; a rear roller; and at least one acid treatment section between the front roller and the rear roller, comprising: a reservoir or dispensing unit; the reservoir or dispensing unit being suspended above the double layer; and the reservoir or dispensing unit comprising a solution containing an acid source with a concentration of approximately 10 ppm to 5500 ppm. In some embodiments, the metal foil of the double layer comprises pure nickel. In some embodiments, the metal foil of the double layer comprises a nickel alloy. In some embodiments, the nickel alloy comprises nickel and iron. In some embodiments, the nickel alloy has a nickel-iron ratio of 85:15. In some embodiments, the nickel alloy has a nickel-iron ratio of 88:12.

[0327] In some embodiments, the bilayer is sintered. In some embodiments, the bilayer comprises a sintered lithium-filled garnet layer.

[0328] In some embodiments, the continuous double-layer processing production line further includes a conveyor belt. In some embodiments, the continuous double-layer processing production line further includes a magnetic sheet. In some embodiments, the continuous double-layer processing production line further includes a conveyor belt and a magnetic sheet. In some embodiments, the magnetic sheet includes a plurality of magnets. In some embodiments, the double layer is located on top of the conveyor belt. In some embodiments, the double layer is located on top of and in contact with the conveyor belt. In some embodiments, the magnetic sheet is located below the conveyor belt. In some embodiments, the magnetic sheet is located below and in contact with the conveyor belt.

[0329] In some embodiments, the continuous double-layer processing production line further includes a first rinsing section. In some embodiments, the continuous double-layer processing production line further includes a first rinsing section and a second rinsing section.

[0330] In some embodiments, the continuous dual-layer processing production line further includes a drying section. In some embodiments, the dual layers move through the dual-layer processing production line.

[0331] In some embodiments, including any of the foregoing embodiments, the acid source contains an acid, and / or its conjugate base, and / or its dissolved ions, selected from the group consisting of: (a) H3PO4 and / or H2PO4 - and / or PO4 3- and / or PO4 2- ; (b) H2SO4 and / or HSO4 - and / or SO4 2- and / or SO4 - ; (c) HCl and / or Cl - ; (d) H3BO3 and / or B(OH)4 - and / or BH2O3 - ; (e) H2TiF6 and / or TiF6 2- ; (f) H2ZrF6 and / or ZrF6 2- ;as well as (g) Their combination.

[0332] In one embodiment, including any of the foregoing embodiments, the acid source also contains water.

[0333] In one embodiment, including any of the foregoing embodiments, the acid source contains H3PO4 and / or H2PO4. - and / or PO4 3- and / or PO4 2- In one embodiment, including any of the foregoing embodiments, the acid source contains H3PO4 and / or H2PO4 in an aqueous solution. - and / or PO4 3- and / or PO4 2- In one embodiment, including any of the foregoing embodiments, the acid source contains H3PO4 and / or H2PO4 in an aqueous solution. - and / or PO4 3- and / or PO4 2- The concentration of which is approximately 85 wt%.

[0334] In some embodiments, the concentration of the acid source in the solution is about 10 ppm to about 5500 ppm.

[0335] In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is about 10 ppm to about 1000 ppm, about 100 ppm to about 800 ppm, about 250 ppm to about 750 ppm, or about 400 ppm to about 600 ppm.

[0336] In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is about 10 ppm to 50 ppm, about 50 ppm to 100 ppm, about 100 ppm to 300 ppm, about 300 ppm to 500 ppm, about 500 ppm to 700 ppm, or about 700 ppm to 1000 ppm.

[0337] In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is about 10 ppm to 25 ppm, about 20 ppm to 40 ppm, about 30 ppm to 50 ppm, about 40 ppm to 60 ppm, or about 45 ppm to 65 ppm. In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is about 300 ppm to 400 ppm, about 350 ppm to 450 ppm, about 400 ppm to 500 ppm, about 450 ppm to 550 ppm, or about 450 ppm to 600 ppm. In one embodiment, including any of the foregoing embodiments, the concentration of the acid source in the solution is about 1000 ppm to 5500 ppm, about 2000 ppm to 5500 ppm, about 3000 ppm to 5500 ppm, or about 4000 ppm to 5500 ppm. In some embodiments, the concentration of the acid source in the solution is about 1000 ppm to 2000 ppm, about 1500 ppm to 2500 ppm, about 2000 ppm to 3000 ppm, about 2500 ppm to 3500 ppm, about 3000 ppm to 4000 ppm, about 3500 ppm to 4500 ppm, about 4000 to 5000 ppm, or about 4500 ppm to 5500 ppm.

[0338] In some embodiments, the concentration of the acid source in the solution is approximately 1000-5000 ppm.

[0339] In one embodiment, including any of the foregoing embodiments, the solution contains an acid source selected from the group consisting of H3PO4, H2TiF6, HCl, H2SO4, H3BO3, H2ZrF6, and combinations thereof, wherein the concentration of the acid source in the acidic solution is about 10 ppm to 25 ppm, about 20 ppm to 40 ppm, about 30 ppm to 50 ppm, about 40 ppm to 60 ppm, or about 45 ppm to 65 ppm. In one embodiment, including any of the foregoing embodiments, the solution contains an acid source selected from the group consisting of H3PO4, H2TiF6, HCl, H2SO4, H3BO3, H2ZrF6, and combinations thereof, wherein the concentration of the acid source in the acidic solution is about 300 ppm to 400 ppm, about 350 ppm to 450 ppm, about 400 ppm to 500 ppm, about 450 ppm to 550 ppm, or about 450 ppm to 600 ppm. In one embodiment, including any of the foregoing embodiments, the solution contains an acid source comprising members selected from the group consisting of H3PO4, H2TiF6, HCl, H2SO4, H3BO3, H2ZrF6, and combinations thereof, wherein the concentration of the acid source in the acidic solution is approximately 1000 ppm to 2000 ppm, approximately 1500 ppm to 2500 ppm, approximately 2000 ppm to 3000 ppm, approximately 2500 ppm to 3500 ppm, approximately 3000 ppm to 4000 ppm, approximately 3500 ppm to 4500 ppm, approximately 4000 to 5000 ppm, or approximately 4500 ppm to 5500 ppm.

[0340] In one embodiment, including any of the foregoing embodiments, the acid source contains H3PO4 and / or H2PO4. - and / or PO4 3- and / or PO4 2- The concentration of the acid source in the solution is approximately 10 ppm to 25 ppm, approximately 20 ppm to 40 ppm, approximately 30 ppm to 50 ppm, approximately 40 ppm to 60 ppm, or approximately 45 ppm to 65 ppm. In one embodiment, including any of the foregoing embodiments, the acid source contains H3PO4 and / or H2PO4. - and / or PO4 3- and / or PO4 2-The concentration of the acid source in the solution is approximately 300 ppm to 400 ppm, approximately 350 ppm to 450 ppm, approximately 400 ppm to 500 ppm, approximately 450 ppm to 550 ppm, or approximately 450 ppm to 600 ppm. In one embodiment, including any of the foregoing embodiments, the acid source contains H3PO4 and / or H2PO4. - and / or PO4 3- and / or PO4 2- The concentration of the acid source in the solution is approximately 1000 ppm to 5500 ppm, approximately 2000 ppm to 5500 ppm, approximately 3000 ppm to 5500 ppm, or approximately 4000 ppm to 5500 ppm. In one embodiment, including any of the foregoing embodiments, the acid source contains H3PO4 and / or H2PO4. - and / or PO4 3- and / or PO4 2- The concentration of the acid source in the solution is approximately 1000 ppm to 2000 ppm, approximately 1500 ppm to 2500 ppm, approximately 2000 ppm to 3000 ppm, approximately 2500 ppm to 3500 ppm, approximately 3000 ppm to 4000 ppm, approximately 3500 ppm to 4500 ppm, approximately 4000 to 5000 ppm, and approximately 4500 ppm to 5500 ppm.

[0341] In one embodiment, including any of the foregoing embodiments, the acid source contains H3PO4 and / or H2PO4. - and / or PO4 3- and / or PO4 2- The concentration of the acid source in the solution is approximately 50 ppm. In one embodiment, including any of the foregoing embodiments, the acid source contains H3PO4 and / or H2PO4. - and / or PO4 3- and / or PO4 2- The concentration of the acid source in the solution is approximately 500 ppm. In one embodiment, including any of the foregoing embodiments, the acid source contains H3PO4 and / or H2PO4. - and / or PO4 3- and / or PO4 2- The concentration of the acid source in the solution is approximately 5000 ppm. In one embodiment, including any of the foregoing embodiments, the acid source contains H3PO4 and / or H2PO4. - and / or PO4 3- and / or PO4 2- The concentration of the acid source in the solution is approximately 5500 ppm.

[0342] In one embodiment, including any of the foregoing embodiments, the acid source further contains water. For example, in one embodiment, including any of the foregoing embodiments, the acid source contains (1) H3PO4 and / or H2PO4. - and / or PO4 3- and / or PO4 2- (2) Water, wherein the concentration of the acid source in the solution is about 10 ppm to 25 ppm, about 20 ppm to 40 ppm, about 30 ppm to 50 ppm, about 40 ppm to 60 ppm, or about 45 ppm to 65 ppm. In further embodiments, including any of the foregoing embodiments, the acid source contains (1) H3PO4 and / or H2PO4. - and / or PO4 3- and / or PO4 2- (2) Water, wherein the concentration of the acid source in the solution is approximately 50 ppm.

[0343] In one embodiment, including any of the foregoing embodiments, the acid source also contains water.

[0344] In some embodiments, including any of the foregoing examples, the solution comprises a solvent. In one embodiment, the solvent is selected from the group consisting of: vinyl sulfite (ES), ethylene carbonate (EC), diethylene carbonate, dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), propyl methyl carbonate, nitroethyl carbonate, propylene carbonate (PC), diethyl carbonate (DEC), methyl propyl carbonate (MPC), dimethyl 2,5-dioxaadipic acid, tetrahydrofuran (THF), γ-butyrolactone (GBL), fluoroethylene carbonate (FEC), fluoromethyl ethylene carbonate (FMEC), methyl trifluoroethyl carbonate (F-EMC), fluorinated 3-(1,1,2,2-tetrafluoroethoxy)-1,1,2,2-tetrafluoropropane / 1,1,2,2-tetrafluoro-3-(1,1,2,2-tetrafluoroethoxy) Propane (F-EPE), fluorinated cyclic carbonates (F-AEC), dioxolane, 1,3-propenesulfonate lactone (PES), sulfolane, acetonitrile (ACN), succinic anionyl ether (SCN), heptanonitrile, octanoic anionyl ether, propionitrile, malononitrile, glutaronitrile (GLN), adiponitrile (ADN), adiponitrile, glutaronitrile, acetophenone, isophorone, benzonitrile, ethyl propionate, methyl propionate, methylene disulfonate, dimethyl sulfate, dimethyl sulfoxide (DMSO), ethyl acetate, methyl butyrate, dimethyl ether (DME), diethyl ether, dioxolane, γ-butyrolactone, methyl benzoate, 2-methyl-5-oxooxazolidine-2-carboxynitrile, N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAC), and combinations thereof. In some examples, the solvent combinations are miscible.

[0345] In some embodiments, including any of the foregoing embodiments, the acidic solution includes the solution described in PCT application WO 2023 / 121838, filed November 30, 2022, entitled “CATHOLYTES FOR A SOLID-STATEBATTERY”, the entire contents of which are incorporated herein by reference.

[0346] In some embodiments, including any of the foregoing examples, the solution contains vinyl sulfite (ES). In some embodiments, including any of the foregoing examples, the solution contains sulfolane.

[0347] In some embodiments, including any of the foregoing examples, the solution contains a solvent selected from the group consisting of: ethylene carbonate (EC), diethylene carbonate, dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), propyl methyl carbonate, nitroethyl carbonate, propylene carbonate (PC), diethyl carbonate (DEC), methyl propyl carbonate (MPC), dimethyl 2,5-dioxaadipic acid, tetrahydrofuran (THF), γ-butyrolactone (GBL), fluoroethylene carbonate (FEC), fluoromethyl ethylene carbonate (FMEC), methyl trifluoroethyl carbonate (F-EMC), fluorinated 3-(1,1,2,2-tetrafluoroethoxy)-1,1,2,2-tetrafluoropropane / 1,1,2,2-tetrafluoro-3-(1,1,2,2-tetrafluoroethoxy)propane (F-EPE), and fluorinated cyclic carbonate (F-AEC).

[0348] In some embodiments, including any of the foregoing examples, the solution contains a solvent selected from the group consisting of: dioxolane, 1,3-propenesulfonyl lactone (PES), sulfolane, acetonitrile (ACN), succinic anionyl, heptonitrile, octanoic anionyl, propionitrile, malononitrile, glutaronitrile (GLN), adiponitrile (ADN), adiponitrile, glutaronitrile, acetophenone, isophorone, benzonitrile, ethyl propionate, methyl propionate, and methylene disulfonate.

[0349] In some embodiments, including any of the foregoing examples, the solution contains a solvent selected from the group consisting of dimethyl sulfate, dimethyl sulfoxide (DMSO), ethyl acetate, methyl butyrate, dimethyl ether (DME), diethyl ether, dioxolane, γ-butyrolactone, methyl benzoate, and 2-methyl-5-oxooxazolidine-2-carboxynitrile.

[0350] In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4 and water; and (2) a solvent containing vinyl sulfite (ES) and sulfolane.

[0351] In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4; and (2) a solvent containing vinyl sulfite (ES) and sulfolane; wherein the concentration of the acid source in the acidic solution is about 10 ppm to 25 ppm, about 20 ppm to 40 ppm, about 30 ppm to 50 ppm, about 40 ppm to 60 ppm, or about 45 ppm to 65 ppm.

[0352] In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4; and (2) a solvent containing vinyl sulfite (ES) and sulfolane; wherein the concentration of the acid source in the acidic solution is about 300 ppm to 400 ppm, about 350 ppm to 450 ppm, about 400 ppm to 500 ppm, about 450 ppm to 550 ppm, or about 450 ppm to 600 ppm.

[0353] In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4; and (2) a solvent containing vinyl sulfite (ES) and sulfolane; wherein the concentration of the acid source in the acidic solution is approximately 50 ppm.

[0354] In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4; and (2) a solvent containing vinyl sulfite (ES) and sulfolane; wherein the concentration of the acid source in the acidic solution is approximately 500 ppm.

[0355] In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4; and (2) a solvent containing vinyl sulfite (ES); the concentration of the acid source in the acidic solution is about 10 ppm to 25 ppm, about 20 ppm to 40 ppm, about 30 ppm to 50 ppm, about 40 ppm to 60 ppm, or about 45 ppm to 65 ppm. In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4; and (2) a solvent containing vinyl sulfite (ES); the concentration of the acid source in the acidic solution is about 300 ppm to 400 ppm, about 350 ppm to 450 ppm, about 400 ppm to 500 ppm, about 450 ppm to 550 ppm, or about 450 ppm to 600 ppm. In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4; and (2) a solvent containing vinyl sulfite (ES); the concentration of the acid source in the acidic solution is about 50 ppm. In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4; and (2) a solvent containing vinyl sulfite (ES); the concentration of the acid source in the acidic solution is about 500 ppm. In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4; and (2) a solvent containing vinyl sulfite (ES); the concentration of the acid source in the acidic solution is about 1000 ppm to 5500 ppm, about 2000 ppm to 5500 ppm, about 3000 ppm to 5500 ppm, or about 4000 ppm to 5500 ppm. In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4; and (2) a solvent containing vinyl sulfite (ES); wherein the concentration of the acid source in the acidic solution is approximately 1000 ppm to 2000 ppm, approximately 1500 ppm to 2500 ppm, approximately 2000 ppm to 3000 ppm, approximately 2500 ppm to 3500 ppm, approximately 3000 ppm to 4000 ppm, approximately 3500 ppm to 4500 ppm, approximately 4000 ppm to 5000 ppm, or approximately 4500 ppm to 5500 ppm. In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4; and (2) a solvent containing vinyl sulfite (ES); wherein the concentration of the acid source in the acidic solution is approximately 5000 ppm.In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4; and (2) a solvent containing vinyl sulfite (ES); the concentration of the acid source in the acidic solution is approximately 5500 ppm.

[0356] In one embodiment, including any of the foregoing embodiments, the acid source further contains water. For example, in one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4 and water; and (2) a solvent containing vinyl sulfite (ES) and sulfolane; the concentration of the acid source in the acidic solution is about 10 ppm to 25 ppm, about 20 ppm to 40 ppm, about 30 ppm to 50 ppm, about 40 ppm to 60 ppm, or about 45 ppm to 65 ppm. In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4 and water; and (2) a solvent containing vinyl sulfite (ES) and sulfolane; the concentration of the acid source in the acidic solution is about 50 ppm.

[0357] In one embodiment, including any of the foregoing embodiments, the acid source further contains water. For example, in one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4 and water; and (2) a solvent containing vinyl sulfite (ES); the concentration of the acid source in the acidic solution is about 10 ppm to 25 ppm, about 20 ppm to 40 ppm, about 30 ppm to 50 ppm, about 40 ppm to 60 ppm, or about 45 ppm to 65 ppm. In one embodiment, including any of the foregoing embodiments, the solution contains: (1) an acid source containing H3PO4 and water; and (2) a solvent containing vinyl sulfite (ES); the concentration of the acid source in the acidic solution is about 50 ppm. Non-limiting embodiments

[0358] This application provides at least the following non-limiting embodiments:

[0359] (a) A method for processing a bilayer comprising a metal foil or metal powder layer and a lithium-filled garnet layer, comprising:

[0360] i. Provide a solution containing an acid source, the concentration of which is approximately 10 ppm to 5500 ppm;

[0361] ii. Contact the bilayer with the solution for about one hour or less; and

[0362] iii. Remove the bilayer from the solution to obtain an acid-treated bilayer.

[0363] (b) According to the method in (a), the acid source contains an acid, and / or its conjugate base, and / or its dissolved ions, selected from:

[0364] i. H3PO4 and / or H2PO4 - and / or PO4 3- and / or PO4 2- ;

[0365] ii. H2SO4 and / or HSO4 - and / or SO4 2- and / or SO4 - ;

[0366] iii. HCl and / or Cl - ;

[0367] iv. H3BO3 and / or B(OH)4 - and / or BH2O3 - ;

[0368] v. H2TiF6 and / or TiF6 2- ;

[0369] vi. H2ZrF6 and / or ZrF6 2- ;as well as

[0370] vii. Their combination.

[0371] (c) According to the method described in (b), the acid source also contains water.

[0372] (d) The method according to any one of (a)-(c) wherein the acid source contains H3PO4.

[0373] (e) The concentration of the acid source in the solution according to any one of (a)-(d) is about 30 ppm, about 50 ppm, about 80 ppm, about 100 ppm, about 300 ppm, about 500 ppm, about 800 ppm, about 1000 ppm, about 1500 ppm, about 2000 ppm, about 2500 ppm, about 3000 ppm, about 4000 ppm, about 4500 ppm, about 5000 ppm, or about 5500 ppm.

[0374] (f) According to the method described in (e), the concentration of the acid source in the acidic solution is approximately 5000 ppm.

[0375] (g) The solution contains vinyl sulfite, sulfolane, or a combination thereof, according to any one of (a)-(f).

[0376] (h) According to the method described in (g), the solution contains vinyl sulfite.

[0377] (i) According to the method described in (g), the solution contains sulfolane and vinyl sulfite, wherein the volume ratio of sulfolane to vinyl sulfite is approximately 3:7 to 5:5.

[0378] (j) According to the method described in (g), the solution contains sulfolane and vinyl sulfite, wherein the volume ratio of sulfolane to vinyl sulfite is approximately 3:7.

[0379] (k) According to any one of (a)-(j), the solution further contains a lithium salt at a concentration of about 0.1 M to 5 M.

[0380] (l) According to the method of (k), the lithium salt is selected from the group consisting of: LiPF6, lithium bis(oxalatoborate) (LiBOB), lithium bis(perfluoroethanesulfonyl)imide (LiBETI), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), LiBF4, LiClO4, LiAsF6, lithium bis(fluorosulfonyl)imide (LiFSI), LiF, LiI, LiBr, LiCl, and combinations thereof.

[0381] (m) According to any one of (a)-(l), the bilayer is in contact with the solution for at least 1 second, at least 10 seconds, at least 1 minute, at least 2 minutes, at least 3 minutes, at least 4 minutes, at least 5 minutes, at least 10 minutes, at least 20 minutes, at least 30 minutes, at least 40 minutes, at least 50 minutes, or one hour.

[0382] (n) The method according to any one of (a)-(m), the method further comprising (iv): contacting the acid-treated bilayer with a first rinsing solution for about 1 second to 1 minute, removing the acid-treated bilayer to obtain a rinsed acid-treated bilayer.

[0383] (o) According to the method described in (n), the first rinsing solution contains vinyl sulfite, sulfolane, or a combination thereof.

[0384] (p) According to the method described in (o), the first rinsing solution contains vinyl sulfite.

[0385] (q) The method according to any one of (a)-(p), the method further comprising (v): contacting the acid-treated bilayer with a second rinsing solution for about 1 second to 1 minute, removing the acid-treated bilayer to obtain a rinsed acid-treated bilayer.

[0386] (r) According to the method described in (q), the second rinse solution contains acetonitrile.

[0387] (s) According to the method described in any one of (a)-(q), the method further comprises (vi): drying the rinsed acid-treated bilayer.

[0388] (t) According to the method described in any one of (a)-(s), the lithium-filled garnet layer in the bilayer is a lithium-filled garnet thin film.

[0389] (u) According to the method described in any one of (a)-(t), the bilayer is sintered.

[0390] (v) According to the method described in any one of (a)-(u), the contacting is carried out in a continuous manner.

[0391] (w) According to the method described in any one of (a)-(u), the bilayer is kept flat by a magnetic sheet.

[0392] (x) An acid-treated bilayer prepared by the method described in any one of (a)-(w).

[0393] (y) According to the acid-treated bilayer described in (x), the bilayer contains members selected from the group consisting of: phosphorus (P), titanium (Ti), chlorine (Cl), sulfur (S), boron (B), zirconium (Zr), their ions, and combinations thereof, and by X-ray photoelectron spectroscopy measurement, its content is greater than about 0.05 atomic percentage.

[0394] (z) According to the acid-treated bilayer described in (x), the lithium-filled garnet layer contains members selected from the group consisting of: phosphorus (P), titanium (Ti), chlorine (Cl), sulfur (S), boron (B), zirconium (Zr), their ions, and combinations thereof, and by X-ray photoelectron spectroscopy measurement, its penetration depth is about 1 μm to 20 μm.

[0395] (aa) According to the acid-treated bilayer described in (x), the bulk phase (non-surface) of the sintered lithium-filled garnet thin film layer conforms to the chemical formula Li A La B Al C M'' D Zr E O F , where 5 < A < 8, 1.5 < B < 4, 0.1 < C < 2, 0 ≤ D < 2, 1 < E < 3, 10 < F < 13, and M'' is selected from the group consisting of: Mo, W, Nb, Y, Ta, Ga, Sb, Ca, Ba, Sr, Ce, Hf, and Rb.

[0396] (bb) The acid - treated bilayer according to (x), the bulk (non - surface) of the sintered lithium - filled garnet thin film layer conforms to a chemical formula selected from the group consisting of: Li A La B M' C M'' D Zr E O F 、Li A La B M' C M'' D Ta E O F 和Li A La B M' C M'' D Nb E O F , where 4 < A < 8.5, 1.5 < B < 4, 0 ≤ C < 2.5, 0 ≤ D < 2.5, 0 < E < 2.5, 10 < F < 14, where M' and M'' are each independently selected from the group consisting of: Al, Mo, W, Nb, Ga, Y, Gd, Sb, Ca, Ba, Sr, Ce, Hf, Rb, and Ta.

[0397] (cc) The acid - treated bilayer according to (x), the bulk (non - surface) of the sintered lithium - filled garnet thin film layer conforms to the chemical formula Li a La b Zr c Al d M'' e O f , where 5 < a < 7.7, 2 < b < 4, 0 < c < 2.5, 0 < d < 2.5, 0 ≤ e < 2.5, 10 < f < 14, and M'' is a metal selected from Nb, Ta, V, W, Mo, and Sb.

[0398] (dd) The acid - treated bilayer according to (x), the bulk (non - surface) of the sintered lithium - filled garnet thin film layer conforms to the chemical formula Li a La b Zr c Al d O f , where 5 < a < 7.7, 2 < b < 4, 0 < c < 2.5, 0 < d < 2.5, 10 < f < 14.

[0399] (ee) The acid - treated bilayer according to (x), the bulk (non - surface) of the sintered lithium - filled garnet thin film layer approximately conforms to Li6La3Zr2O 12 Al 1 / 3 ; approximately conforms to Li 6.25 La3Zr2O12 Al 0.25 Approximately conforms to Li4La3Zr2O 12 Al1; approximately conforms to Li 6.7 La3Zr2O 12 Al 0.3 Or approximately conforming to Li7La3Zr2O 12 .

[0400] (ff) According to any one of (x)-(ee), the bulk phase (non-surface) of the sintered lithium-filled garnet film layer is polycrystalline.

[0401] (gg) An acid-treated bilayer according to any one of (x)-(ff) has an areal resistivity (ASR) of approximately 5 Ω-cm at 25°C. 2 Up to 50 Ω-cm 2 .

[0402] (hh) According to the acid-treated bilayer described in (g), the bilayer has an area resistivity (ASR) of approximately 5 Ω-cm at 25°C. 2 Up to 30 Ω-cm 2 .

[0403] (ii) The acid-treated bilayer according to (g) has an area resistivity (ASR) of approximately 5 Ω-cm at 25°C. 2 Up to 25 Ω-cm 2 .

[0404] (jj) After the acid-treated bilayer according to any one of (x)-(ii) is subjected to a high temperature and high pressure (HTHV) test at 60°C for one month, the area resistivity (ASR) of the bilayer increases by no more than about 50%.

[0405] (kk) According to (jj), after one month of HTHV testing at 60°C, the area resistivity (ASR) of the bilayer increases by no more than about 30%.

[0406] (ll) An acid-treated bilayer according to any one of (x)-(kk), after acid treatment and storage in dry air for up to 21 days, characterized by an atomic percentage of functional groups CO3 and Zr of about 5 but greater than 0, as measured by XPS.

[0407] (mm) An acid-treated bilayer according to any one of (x)-(ll), measured by XPS one week after HTHV testing, is characterized by an atomic percentage of functional groups CO3 and Zr of about 1 but greater than 0.

[0408] (nn) An electrochemical cell or rechargeable cell comprising any one of (x)-(mm) a bilayer.

[0409] (oo) A bilayer comprising a metal foil or metal powder layer and a lithium-filled garnet layer, the lithium-filled garnet layer containing members selected from the group consisting of phosphorus (P), titanium (Ti), chlorine (Cl), sulfur (S), boron (B), zirconium (Zr), their ions, and combinations thereof, having a penetration depth of approximately 1 μm to 20 μm as measured by X-ray photoelectron spectroscopy (XPS).

[0410] (pp) According to the bilayer described in (oo), the lithium-filled garnet layer conforms to the chemical formula Li a La b Zr c O d Al e Where 5≤a≤8, 2≤b≤4, 1≤c≤2, 11≤d≤14, and 0≤e≤1, by choosing a, b, c, d, and e, the chemical formula Li is made... a La b Zr c O d Al e It is electrically neutral.

[0411] (qq) According to (pp), the double layer is 6, 6.25, 6.50, 6.75 or 7.

[0412] (rr) The double layer according to (oo) or (pp), where e is 0, 0.25, 0.5, 0.75 or 1.

[0413] (ss) A double layer according to any one of (oo)-(rr), where b is 3 and c is 2.

[0414] (tt) A double layer according to any one of (ap)-(as), wherein d is 12.

[0415] (uu) According to (pp), the two layers are 6.25, b is 3, c is 2, d is 12, and e is 0.25.

[0416] (vv) According to (pp), the two layers are approximately 6.25, b is approximately 3, c is approximately 2, d is approximately 12, and e is approximately 0.25.

[0417] (ww) A bilayer according to any one of (oo)-(vv), wherein the bilayer contains an acid, and / or its conjugate base, and / or its dissolved ion incorporated or bonded to the bilayer, wherein the acid, and / or its conjugate base, and / or its dissolved ion is selected from the group consisting of:

[0418] i. H3PO4 and / or H2PO4 - and / or PO4 3- and / or PO4 2- ;

[0419] ii. H2SO4 and / or HSO4 - and / or SO4 2- and / or SO4 - ;

[0420] iii. HCl and / or Cl - ;

[0421] iv. H3BO3 and / or B(OH)4 - and / or BH2O3 - ;

[0422] v. H2TiF6 and / or TiF6 2- ;

[0423] vi. H2ZrF6 and / or ZrF6 2- ;as well as

[0424] vii. Their combination.

[0425] (xx) A bilayer according to any one of (oo)-(ww), characterized in that it has a layer of less than 1 μm thereon, the layer containing lithium carbonate, lithium hydroxide, lithium oxide, their hydrates, their oxides, or combinations thereof.

[0426] (yy) According to any one of (oo)-(ww), the bilayer has a lithium carbonate content of about less than 1 atomic percentage but greater than 0, as measured by X-ray photoelectron spectroscopy (XPS).

[0427] (zz) A bilayer according to any one of (ww)-(yy), wherein the bilayer contains H3PO4 and / or H2PO4. - and / or PO4 3- and / or PO4 2- .

[0428] (aaa) The bilayer according to any one of (ww)-(zz) contains phosphorus and has a penetration depth of about 1 μm to 20 μm, as measured by X-ray photoelectron spectroscopy.

[0429] (bbb) A bilayer according to any one of (ww)-(aaa), the bilayer comprising a phosphorus-containing layer containing Li3PO4, LiH2PO4 or a combination thereof.

[0430] (ccc) According to (bbb), the phosphorus-containing layer is continuous.

[0431] (ddd) According to (bbb), the phosphorus-containing layer is discontinuous.

[0432] (eee) A bilayer according to any one of (oo)-(ddd), characterized in that the atomic percentage of P to Zr is about 1.5 to 10 as measured by XPS.

[0433] (fff) A bilayer according to any one of (oo)-(ddd), characterized in that the atomic percentage of P to Zr, as measured by XPS, is about 1.5 to 3.

[0434] (ggg) The bilayer according to any one of (oo)-(fff), wherein the bilayer is acid-treated.

[0435] (hhh) The bilayer according to any one of (oo)-(ggg) is sintered.

[0436] (iii) A continuous double-layer processing production line, comprising a front roller, a rear roller, and at least one acid treatment section between the front roller and the rear roller;

[0437] The front roller is wound with a double layer, the double layer comprising a metal foil or metal powder layer and a lithium-filled garnet layer; the metal layer is in contact with the front roller.

[0438] The acid treatment section includes a reservoir or a dispensing unit; the reservoir or the dispensing unit is suspended above the double layer; the reservoir or the dispensing unit contains a solution containing an acid source at a concentration of approximately 10 ppm to 5500 ppm.

[0439] (jjj) The continuous double-layer processing production line according to (iii) further includes a conveyor belt and a magnetic sheet, the double layer being located on top of the conveyor belt and the magnetic sheet being located below and in contact with the conveyor belt.

[0440] (kkk) The continuous double-layer processing production line according to (iii) or (jjj) also includes a drying section. Example

[0441] X-ray photoelectron spectroscopy (XPS) measurements were performed on a Thermo Scientific Model K-Alpha 1 XPS instrument. A monochromatic Al X-ray source with an X-ray energy of 1486.6 eV and a spot size of 400 μm was used. The baseline pressure during measurement was 2 * 10⁻⁶. -9 mbar or lower.

[0442] Unless otherwise specified, lithium-filled garnet films are prepared by depositing a slurry of lithium-filled garnet precursor material onto an aluminum substrate using a doctor blade method and sintering it at 1000°C to 1300°C to produce a lithium-filled garnet film with a thickness of approximately 50 micrometers (μm).

[0443] Unless otherwise specified, the co-sintered thin film (CSC film) is prepared according to the following steps: A slurry of lithium-filled garnet precursor material is cast onto a Mylar polyester film. A second layer of slurry, including nickel particles and additional lithium-filled garnet precursor material (by screen printing or casting), is deposited onto the lithium-filled garnet material slurry. The resulting CSC bilayer is sintered on an aluminum substrate at 1000°C to 1300°C to produce a CSC film with a thickness of approximately 50 micrometers.

[0444] Unless otherwise specified, the bilayer (film on metal foil) is prepared as follows: A slurry of lithium-filled garnet precursor material is poured onto the metal foil and dried to form a green strip. The green strip cast on the metal foil (bilayer before sintering) is unfolded and cut to a size suitable for sintering. This is done using a laser cutter or a blade punching tool. The discrete green strips are then stacked between a pad assembly and placed on a support frame for the sintering equipment. The pad assembly refers to a dense Al2O3 plate on which the green strip is placed, green strip side up, followed by a ceramic or metal frame assembly, then a metal plate coated with LiAlO2, and then another dense Al2O3 plate. Example 1: Acid Treatment of CSC Thin Films

[0445] Preparation of an ESS solution containing 50 ppm H3PO4: Prepare a vinyl sulfite:sulfolane (ESS, 7:3 volume ratio) solution in a large aluminum (Al) bottle. Add molecular sieves (baked at 220°C under vacuum for 12 hours) at a mass ratio (relative to the total mass of solvent) of 10% to the ESS stock solution. Dehydrate the ESS stock solution on the molecular sieves for 14 days until the water content is less than 10 ppm as determined by Karl Fischer titration. Aliquot the now dried ESS stock solution into appropriately sized smaller plastic bottles using graduated cylinders. Measure the corresponding volume of phosphoric acid from the 85% H3PO4 (w / w) aqueous solution stock bottle and aliquot it into the corresponding ESS aliquots to prepare an ESS solution containing 50 ppm H3PO4. Then, manually shake the ESS aliquots containing 50 ppm H3PO4 for 5 seconds and allow them to stand for at least 2 minutes before use.

[0446] Rinsing the CSC film in a solvent containing H3PO4: Place the CSC film in a separate HDPE plastic container with the cathode side facing up. Pour an aliquot (15 mL) of ESS containing 50 ppm H3PO4 onto each solid CSC film, ensuring complete immersion. Then cover the plastic container and allow the CSC film to stand in the solution for 5 minutes to 1 hour. After immersion, remove the double layer from the 50 ppm H3PO4 ESS immersion solution and transfer it to a new HDPE container containing rinsing solution (15 mL vinyl sulfite). Place the CSC film in the rinsing solution with the garnet side facing up for 5 minutes. Then remove the CSC film from the rinsing solution, place it on absorbent paper, and dry it with compressed dry air (CDA). During the drying process, turn the CSC film back and forth to ensure that there is no residual vinyl sulfite coating on either the anode or cathode side of the CSC film. Example 2: ASR Study of Acid-Treated CSC Thin Films

[0447] Following the procedure of Example 1, the CSC film was cut into 11 mm discs. Individual bilayers were used in electrochemical cells. The cells included a lithium metal anode and a nickel-manganese-cobalt oxide active material. The cells underwent a formation cycle and were then charged to 4.35 V at a C / 3 rate at 25°C. The data presented in Figure 1 are the cell areal resistivity (ASR) of the first C / 3 cycle, compared to 11 individual cells of bilayers treated with ESS solutions of H3PO4 (50 ppm), H2TiF6 (50 ppm), or H3BO3 (100 ppm) with solid-state bilayers treated with LiBF4. The cells were then placed in a 60°C oven and stored at a settling voltage close to 4.35 V for 30 days. After high-temperature, high-pressure (HTHV) exposure, the cells were returned to a 25°C oven for C / 3 discharge (2.8 V–4.35 V) and a complete C / 3 cycle (2.8 V–4.35 V). The data in Figure 2 represents the ASR (Advanced Performance Reduction) after a complete C / 3 cycle following high-temperature, high-pressure storage of the battery. This test is referred to in this application as the High-Voltage High-Temperature (HVHT) test.

[0448] Figures 1 and 2 show a comparison of the ASR of an acid-treated solid bilayer treated with an ESS solution containing H3PO4 (50 ppm), H2TiF6 (50 ppm), and H3BO3 (100 ppm) with that of a solid bilayer treated with LiBF4. The acid-treated bilayer was processed according to the procedure in Example 1.

[0449] Figure 1 shows the ASR after acid treatment, and Figure 2 shows the ASR after the high-temperature and high-pressure (HTHV) test in Example 2. As shown in Figure 2, the bilayer treated with H3PO4, after one month of HTHV testing in Example 2, is characterized by an ASR of less than 60 ohms*cm. 2 . Example 3: Acid treatment in a double layer

[0450] Preparation of an ES solution containing 5000 ppm H3PO4: Prepare a vinyl sulfite (ES) solution in a large tank on a chemical wet processing bench. Measure the appropriate mass of phosphoric acid from a 99.9 wt% H3PO4 (w / w) stock bottle and add it to the ES tank to prepare an ES solution containing 5000 ppm H3PO4. Allow the 5000 ppm H3PO4 to completely dissolve in the ES tank for 1 hour.

[0451] Rinse the double layer with a solvent containing H3PO4: Place the double layer into a PTFE (polytetrafluoroethylene) cartridge with a single film slot, the double layer comprising a sintered lithium-filled garnet film on pure nickel foil or nickel alloy foil. Then immerse the double layer in an ES immersion solution containing 5000 ppm H3PO4 for 2 to 5 minutes. After immersion, remove the PTFE cartridge containing the double layer from the ES immersion solution containing 5000 ppm H3PO4 and transfer it to a new tank containing vinyl sulfite rinsing solution on a wet processing station. Let the PTFE cartridge containing the double layer remain in the rinsing solution for 10 seconds. Then remove the PTFE cartridge containing the double layer from the rinsing solution and transfer it to a final rinsing tank containing acetonitrile rinsing solution on a wet processing station. Let the PTFE cartridge containing the double layer remain in the final rinsing solution for 10 seconds. The double-layered PTFE cartridge is then removed from the rinsing solution and transferred to an empty reservoir, where it is dried with compressed dry air (CDA). Once drying is complete, the double layer is removed individually from the PTFE cartridge. Example 4: ASR Study of Acid-Treated Bilayer

[0452] After processing according to the procedure in Example 3, the bilayer was cut into 11 mm discs. Individual bilayers were used in electrochemical cells. The cells included a lithium metal anode. The cells included nickel manganese cobalt (NMC) oxide active material. The cells were formed and cycled, then charged to 4.25 V at a C / 3 rate at 25°C. The data in Figure 3 are the areal resistivity (ASR) of 11 individual cells of the bilayer treated with H3PO4 in 5000 ppm ES (ethylene sulfite) solution during the first C / 3 cycle. The cells were then placed in a 60°C oven and stored at a resting voltage close to 4.25 V for 30 days. After high-temperature and high-pressure exposure, the cells were returned to a 25°C oven for C / 3 discharge (2.8 V–4.25 V) and a complete C / 3 cycle (2.8 V–4.25 V). The data in Figure 4 are the ASR of the cells after a complete C / 3 cycle following high-temperature and high-pressure storage. This test is referred to in this application as the High Voltage High Temperature (HVHT) test.

[0453] Figures 3 and 4 show the ASR of the acid-treated solid bilayer after treatment with H3PO4 (5000 ppm) ES solution. Figure 3 is the ASR after acid treatment, and Figure 4 is the ASR after high temperature and high pressure (HTHV) testing in Example 4. The acid-treated bilayer was processed according to the procedure in Example 3. Example 5: Acid treatment and ASR study of CSC thin films

[0454] CSC bilayers, comprising a lithium-filled garnet film and a layer comprising metal powder and lithium-filled garnet, were treated according to the procedure of Example 3. Figures 5 and 6 show the ASRs of these acid-treated CSC bilayers treated with H3PO4 in 50 ppm, 500 ppm, and 5000 ppm ES solutions. Figure 5 shows the ASR after acid treatment, and Figure 6 shows the ASR after high-temperature and high-pressure (HTHV) testing in Example 4. Slight differences in ASRs exist between the bilayers treated with 50 ppm, 500 ppm, and 5000 ppm H3PO4, but all ASR values ​​remain within an acceptable range (30-35 ohms*cm). 2 Furthermore, as shown in Figure 6, the bilayer ASR treated with 50 ppm, 500 ppm, and 5000 ppm H3PO4 still remained below 66 ohms*cm after the HTHV test in Example 4. 2 . Example 6 Characterization of surface acid-treated bilayer

[0455] The bilayer treated with H3PO4 (as described in Examples 1 and 3) was characterized by XPS. The bilayer was transferred to an XPS system (ThermoFisher Scientific K-Alpha) under a dry atmosphere (dew point -50°C). Monochromatic, microfocused Al-Kα was used as the X-ray source at 10... -8 XPS analysis was performed under Torr pressure. The analysis region had a diameter of 400 μm. The XPS spectra were fitted using a Gaussian / Lorentz product function peak shape model combined with the background.

[0456] The results for the bilayer before formation, after formation, and one week after HTHV testing in Examples 2 or 4 are listed in Table 1. The results have been normalized to Zr3d atom counts, and the observed numerical ranges are provided.

[0457] Table 1. XPS Analysis

[0458]

[0459] The above embodiments and examples are illustrative and not limiting. Those skilled in the art will recognize or be able to determine numerous equivalents of specific compounds, materials, and procedures using no more than conventional experiments. All such equivalents are considered to fall within the scope of the appended claims.

Claims

1. A method for processing a double layer, said double layer comprising a metal foil or metal powder layer and a lithium-filled garnet layer, comprising: (a) Provide a solution containing an acid source, the concentration of which is about 10 ppm to 5500 ppm; (b) Contact the bilayer with the solution for about one hour or less; as well as (c) Remove the bilayer from the solution to obtain an acid-treated bilayer.

2. The method according to claim 1, wherein the acid source contains an acid, and / or its conjugate base, and / or its dissolved ions, selected from: (a) H3PO4 and / or H2PO4 - and / or PO4 3- and / or PO4 2- ; (b) H2SO4 and / or HSO4 - and / or SO4 2- and / or SO4 - ; (c) HCl and / or Cl - ; (d) H3BO3 and / or B(OH)4 - and / or BH2O3 - ; (e) H2TiF6 and / or TiF6 2- ; (f) H2ZrF6 and / or ZrF6 2- ;as well as (g) Their combination.

3. The method according to claim 1 or 2, wherein the acid source contains H3PO4.

4. The method according to any one of claims 1-3, wherein the concentration of the acid source in the acidic solution is about 5000 ppm.

5. The method according to any one of claims 1-4, wherein the solution contains vinyl sulfite.

6. The method according to any one of claims 1-5, the method further comprising (d): contacting the acid-treated bilayer with a first rinsing solution for about 1 second to 1 minute, and removing the acid-treated bilayer from the first rinsing solution to obtain a rinsed acid-treated bilayer.

7. The method according to any one of claims 1-6, further comprising (e): contacting the acid-treated bilayer with a second rinsing solution for about 1 second to 1 minute, and removing the acid-treated bilayer from the second rinsing solution to obtain a rinsed acid-treated bilayer.

8. The method according to any one of claims 1-7, the method further comprising (f): drying the rinsed acid-treated bilayer.

9. The method according to any one of claims 1-8, wherein the contact is performed continuously.

10. The method according to any one of claims 1-9, wherein the double layer is kept flat by a magnetic sheet during process (b).

11. An acid-treated bilayer prepared by the method of any one of claims 1-10.

12. The acid-treated bilayer according to claim 11, wherein the bilayer contains members selected from the group consisting of phosphorus (P), titanium (Ti), chlorine (Cl), sulfur (S), boron (B), zirconium (Zr), their ions, and combinations thereof, and the content thereof is greater than about 0.05 atomic percent as measured by X-ray photoelectron spectroscopy.

13. The acid-treated bilayer according to claim 1, wherein the bilayer has an area resistivity (ASR) of approximately 5 Ω-cm at 25°C. 2 Up to 30 Ω-cm 2 .

14. The acid-treated bilayer according to claim 11 or 12, after one month of HTHV testing at 60°C, the area resistivity (ASR) of the bilayer increases by no more than about 30%.

15. The acid-treated bilayer according to any one of claims 11-14, wherein the bilayer is stored under dry air conditions for up to 21 days after acid treatment, and as measured by XPS, is characterized by functional groups The atomic percentages of CO3 and Zr are approximately less than 5 but greater than 0.

16. The acid-treated bilayer according to any one of claims 11-15, wherein the bilayer is measured by XPS one week after high temperature and high pressure (HTHV) testing, characterized by functional groups The atomic percentages of CO3 and Zr are approximately less than 1 but greater than 0.

17. A bilayer comprising a metal foil or metal powder layer and a lithium-filled garnet layer, the lithium-filled garnet layer containing members selected from the group consisting of phosphorus (P), titanium (Ti), chlorine (Cl), sulfur (S), boron (B), zirconium (Zr), their ions, and combinations thereof, having a penetration depth of about 1 μm to 20 μm as measured by X-ray photoelectron spectroscopy (XPS).

18. The bilayer according to claim 17, wherein the lithium-filled garnet layer conforms to the chemical formula Li a La b Zr c O d Al e Where 5≤a≤8, 2≤b≤4, 1≤c≤2, 11≤d≤14, and 0≤e≤1, by choosing a, b, c, d, and e, the chemical formula Li is made... a La b Zr c O d Al e It is electrically neutral.

19. The double layer according to claim 18, wherein a is 6.25, b is 3, c is 2, d is 12, and e is 0.

25.

20. The bilayer according to any one of claims 17-19, wherein the bilayer contains an acid, and / or its conjugate base, and / or its dissolved ion incorporated or bonded to the bilayer, wherein the acid, and / or its conjugate base, and / or its dissolved ion is selected from the group consisting of: (a) H3PO4 and / or H2PO4 - and / or PO4 3- and / or PO4 2- ; (b) H2SO4 and / or HSO4 - and / or SO4 2- and / or SO4 - ; (c) HCl and / or Cl - ; (d) H3BO3 and / or B(OH)4 - and / or BH2O3 - ; (e) H2TiF6 and / or TiF6 2- ; (f) H2ZrF6 and / or ZrF6 2- ;as well as (g) Their combination.

21. The bilayer according to any one of claims 17-20, wherein the lithium carbonate content of the bilayer, as measured by X-ray photoelectron spectroscopy (XPS), is less than 1 but greater than 0 atomic percentage.

22. The bilayer according to any one of claims 17-21, wherein the bilayer contains H3PO4 and / or H2PO4. - and / or PO4 3- and / or PO4 2- .

23. The bilayer according to any one of claims 17-22, wherein the bilayer comprises a phosphorus-containing layer containing Li3PO4, LiH2PO4, or a combination thereof.

24. The double layer according to any one of claims 17-23, characterized in that, The atomic percentages of P and Zr, as measured by XPS, are approximately 1.5 to 3.

25. The bilayer according to any one of claims 17-24, wherein the bilayer is acid-treated.

26. A continuous double-layer processing production line, comprising a front roller, a rear roller, and at least one acid treatment section between the front roller and the rear roller; The front roller is wound with a double layer, the double layer comprising a metal foil or metal powder layer and a lithium-filled garnet layer; the metal layer is in contact with the front roller. The acid treatment section includes a reservoir or a dispensing unit; the reservoir or the dispensing unit is suspended above the double layer; the reservoir or the dispensing unit contains a solution containing an acid source at a concentration of approximately 10 ppm to 5500 ppm.

27. The continuous double-layer processing production line according to claim 26 further includes a conveyor belt and a magnetic sheet, wherein the double layer is located above the conveyor belt and the magnetic sheet is located below the conveyor belt and in contact with it.

28. The continuous double-layer processing production line according to claim 26 or 27 further includes a drying section.

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