Oxyhalide solid-state electrolyte and preparation method therefor, solid-state battery cell, battery device, and electric device

Abstract

An oxyhalide solid-state electrolyte and a preparation method therefor, a solid-state battery cell, a battery device, and an electric device. The general formula of the oxyhalide solid-state electrolyte is LiaAlmXnYbOc, wherein X includes a trivalent metal element other than Al, Y includes a halogen, 0<a≤9, 0<m, 0≤n, 0<m+n≤10, 0<a / m≤1, 0<b≤36, and 0<c≤10. The crystal structure of the oxyhalide solid-state electrolyte comprises a crystalline phase and an amorphous phase, wherein the crystalline phase is a LiCl phase. The X-ray diffraction pattern of the solid-state electrolyte has diffraction peaks at positions of 31.62°-32.62°, 34.40°-35.40°, 49.64°-50.64°, and 59.25°-60.25°. The solid-state battery cell has improved electrochemical performance.

Description

Halogen oxide solid electrolytes and their preparation methods, solid-state battery cells, battery devices, and electrical devices.

[0001] Cross-reference to related applications

[0002] This application claims priority to Chinese Patent Application No. 202510491996.9, filed on April 18, 2025, entitled “Halooxide Solid Electrolyte and Preparation Method Thereof, Solid Battery Cell, Battery Device, and Power-Consuming Device”, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of battery technology, specifically to a halide oxide solid electrolyte and its preparation method, a solid battery cell, a battery device, and an electrical device. Background Technology

[0004] Batteries are widely used in electronic devices such as mobile phones, laptops, electric vehicles, electric cars, electric airplanes, electric ships, electric car toys, electric toy ships, electric toy airplanes, and power tools.

[0005] In the development of battery cells, improving the cycle performance of battery cells is one of the urgent problems to be solved. Summary of the Invention

[0006] To address the aforementioned technical problems, this application provides a halide oxide solid electrolyte and its preparation method, a solid battery cell, a battery device, and an electrical device.

[0007] Firstly, embodiments of this application provide a halide oxide solid electrolyte. The general formula for halide oxide solid electrolytes is Li. a Al m X n Y b O c X includes trivalent metal elements other than Al, and Y includes halogens; 0 < a ≤ 9, 0 < m, 0 ≤ n, 0 < m + n ≤ 10, 0 < a / m ≤ 1, 0 < b ≤ 36, 0 < c ≤ 10; the crystal structure of the halide oxide solid electrolyte includes crystalline and amorphous phases, with the crystalline phase being the LiCl phase. The X-ray diffraction pattern of the halide oxide solid electrolyte has diffraction peaks at positions of 31.62°-32.62°, 34.40°-35.40°, 49.64°-50.64°, and 59.25°-60.25°.

[0008] The halide oxide solid electrolyte provided in this application replaces part of the halogen by doping with oxygen. Since the Li-O bond has a lower bond energy than the Li-Cl bond, the oxygen doping can weaken the Coulomb interaction between Li and Cl, resulting in a faster migration rate of lithium ions in the lattice / amorphous network of the halide oxide solid electrolyte. This improves the ionic conductivity of the halide oxide solid electrolyte and thus improves the cycle performance of the solid-state battery. At the same time, doping can make the halide oxide solid electrolyte have both crystalline and amorphous phases. The presence of the amorphous phase can give the halide oxide solid electrolyte a certain degree of viscoelasticity, thereby improving the solid-solid contact effect between the halide oxide solid electrolyte and other materials (such as positive electrode active materials), further improving the lithium ion transport efficiency.

[0009] In some embodiments, 4≤a≤9, 5≤m≤10, 5≤m+n≤10, 7≤b≤35, and 6≤c≤10.

[0010] In some embodiments, X includes one or more of Fe, In, Sb, and Bi.

[0011] In some embodiments, the glass transition temperature of the halide oxide solid electrolyte is -30°C to -10°C.

[0012] In some embodiments, the glass transition temperature of the halide oxide solid electrolyte is -20°C to -15°C.

[0013] In some embodiments, the melting temperature of the halide oxide solid electrolyte is 60°C to 260°C.

[0014] In some embodiments, the ionic conductivity of the halide oxide solid electrolyte at 25°C is 1×10⁻⁶. -4 mS / cm to 1×10 -2 mS / cm.

[0015] In some embodiments, the positive electrode includes a positive current collector and a positive electrode film layer located on at least one side of the positive current collector, the positive electrode film layer including a halide oxide solid electrolyte; the mass percentage of the solid electrolyte is 5%-35% based on the total mass of the positive electrode film layer.

[0016] Secondly, embodiments of this application provide a method for preparing a halide oxide solid electrolyte, comprising the following steps:

[0017] According to the chemical formula Li a Al m X n Y b O cProvide raw materials including lithium source, aluminum source, X element source, halogen source and oxygen source, where X includes trivalent metal elements other than Al, Y includes halogens; 0<a≤9, 0<m, 0≤n, 0<m+n≤10, 0<a / m≤1, 0<b≤36, 0<c≤10;

[0018] A precursor is obtained by mixing a lithium source, an aluminum source, an X element source, and a halogen source and subjecting them to a first heat treatment.

[0019] The precursor was mixed with an oxygen source and subjected to a second heat treatment to obtain a halide oxide solid electrolyte. The crystal structure of the halide oxide solid electrolyte includes a crystalline phase and an amorphous phase, with the crystalline phase being the LiCl phase. The X-ray diffraction pattern of the halide oxide solid electrolyte shows diffraction peaks at positions of 31.62°-32.62°, 34.40°-35.40°, 49.64°-50.64°, and 59.25°-60.25°.

[0020] The oxygen source includes crystalline hydrates, whose melting point is lower than the temperature of the second heat treatment.

[0021] According to the embodiments of this application, the method for preparing halide oxide solid electrolytes provided in this application uses crystalline hydrates as an oxygen source to provide oxygen element doping during the preparation process of halide oxide solid electrolytes. The crystalline hydrates can provide oxygen element during low-temperature decomposition, and the low-temperature decomposition characteristics of crystalline hydrates are conducive to the formation of a more porous polyanionic cluster environment. This generates a weak LiCl crystalline phase and an amorphous phase in the halide oxide solid electrolyte, weakening the Coulomb interaction between Li-Cl, and allowing lithium ions to have a faster migration rate in the lattice / amorphous network, thereby improving the ionic conductivity of the halide oxide solid electrolyte. Therefore, the preparation method of the second aspect embodiment of this application can be used to prepare the halide oxide solid electrolyte of the first aspect embodiment of this application.

[0022] In some embodiments, the crystalline hydrate includes one or more of AlCl3·6H2O, FeCl3·6H2O, CrCl3·6H2O, InCl3·4H2O, and YCl3·6H2O.

[0023] In some embodiments, the lithium source, aluminum source, and element X source are all anhydrous compounds.

[0024] In some embodiments, the lithium source includes lithium-containing halides.

[0025] In some embodiments, the aluminum source includes an aluminum halide.

[0026] In some embodiments, the source of element X includes a halide containing element X.

[0027] In some embodiments, the temperature of the first heat treatment is 150°C-300°C.

[0028] In some embodiments, the first heat treatment time is 3h-10h.

[0029] In some embodiments, the temperature of the second heat treatment is 200°C-300°C.

[0030] In some embodiments, the second heat treatment time is 0.5h-5h.

[0031] Thirdly, embodiments of this application provide a solid-state battery cell.

[0032] Fourthly, embodiments of this application provide a battery device, including a solid-state battery cell according to the third aspect of this application.

[0033] Fifthly, embodiments of this application provide an electrical device, including a solid-state battery cell according to the third aspect of this application or a battery device according to the fourth aspect of this application. Attached Figure Description

[0034] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly described below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on the drawings without creative effort.

[0035] Figure 1 is a schematic diagram of the structure of a vehicle provided in some embodiments of this application.

[0036] Figure 2 is a schematic diagram of the explosion of a battery provided in some embodiments of this application.

[0037] Figure 3 is an exploded view of the battery module shown in Figure 2.

[0038] Figure 4 shows the X-ray diffraction (XRD) patterns of the solid electrolytes in some Examples 1 and Comparative Example 1 of this application.

[0039] The accompanying drawings are not necessarily drawn to scale.

[0040] The reference numerals in the attached drawings are explained as follows: 1. Vehicle; 2. Battery unit; 3. Controller; 4. Motor; 5. Housing; 5a. First housing section; 5b. Second housing section; 5c. Reception space; 6. Battery module; 7. Battery cell. Detailed Implementation

[0041] The following detailed description, with appropriate reference to the accompanying drawings, discloses embodiments of the halide oxide solid electrolyte, its preparation method, solid-state battery cell, battery device, and power-consuming device of this application. However, unnecessary detailed descriptions may be omitted. For example, detailed descriptions of well-known matters and repetitive descriptions of practically identical structures may be omitted. This is to avoid unnecessarily lengthy descriptions and to facilitate understanding by those skilled in the art. Furthermore, the accompanying drawings and the following description are provided for the purpose of enabling those skilled in the art to fully understand this application and are not intended to limit the subject matter of the claims.

[0042] The "range" disclosed in this application is defined by a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of a particular range. Ranges defined in this way can include or exclude endpoints and can be arbitrarily combined; that is, any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60-120 and 80-110 are listed for a specific parameter, it is expected that ranges of 60-110 and 80-120 are also included. Furthermore, if minimum range values ​​of 1 and 2 are listed, and if maximum range values ​​of 3, 4, and 5 are listed, then the following ranges are all expected: 1-3, 1-4, 1-5, 2-3, 2-4, and 2-5. In this application, unless otherwise stated, the numerical range "ab" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0-5" indicates that all real numbers between "0-5" have been listed in this article; "0-5" is simply a shortened representation of these numerical combinations. Furthermore, when a parameter is stated as an integer greater than or equal to "yes", it is equivalent to disclosing that the parameter is, for example, an integer such as 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0043] Unless otherwise specified, all embodiments and optional embodiments of this application may be combined with each other to form new technical solutions, and such technical solutions should be considered to be included in the disclosure of this application.

[0044] Unless otherwise specified, all technical features and optional technical features of this application may be combined to form new technical solutions, and such technical solutions shall be deemed to be included in the disclosure of this application.

[0045] Unless otherwise specified, all steps of this application may be performed sequentially or randomly, preferably sequentially. For example, if the method includes steps (a) and (b), it means that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, if the method may also include step (c), it means that step (c) may be added to the method in any order. For example, the method may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc.

[0046] Unless otherwise specified, in this application, the terms "first," "second," etc., are used to distinguish different objects, rather than to describe a specific order or primary / secondary relationship.

[0047] In this application, the terms "multiple" or "various" refer to two or more kinds.

[0048] In the description of the embodiments of this application, unless otherwise specified, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0049] Unless otherwise stated, the terms used in this application have the common meanings as commonly understood by those skilled in the art.

[0050] Unless otherwise stated, the values ​​of the parameters mentioned in this application can be determined using various testing methods commonly used in the art, for example, according to the testing methods given in the embodiments of this application. Unless otherwise stated, the test temperature for each parameter is 25°C.

[0051] The battery device mentioned in the embodiments of this application may be a single physical module comprising one or more battery cells to provide higher voltage and capacity.

[0052] A single battery cell is the smallest unit that makes up a battery device, and it can independently perform the functions of charging and discharging. When there are multiple battery cells, they are connected in series, parallel, or mixed connections through a busbar.

[0053] In some embodiments, the battery device may be a battery module; when there are multiple battery cells, the multiple battery cells are arranged and fixed to form a battery module.

[0054] In some embodiments, the battery device may be a battery pack, which includes a housing and individual battery cells, with the individual battery cells or battery modules housed within the housing.

[0055] In some embodiments, the housing may be part of the vehicle's chassis structure. For example, a portion of the housing may be at least a part of the vehicle's floor, or a portion of the housing may be at least a part of the vehicle's crossbeams and longitudinal beams.

[0056] In some embodiments, the battery device may be an energy storage device. Energy storage devices include energy storage containers, energy storage cabinets, etc.

[0057] The technical solutions described in the embodiments of this application are applicable to battery devices and electrical devices that use battery devices.

[0058] Battery devices can be used as the power source for electrical devices or as energy storage units for electrical devices. Electrical devices can be, but are not limited to, mobile devices (such as mobile phones, tablets, laptops, etc.), vehicles (such as pure electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, electric bicycles, electric scooters, electric golf carts, electric trucks, etc.), electric trains, ships and satellites, energy storage systems, etc.

[0059] Electrical devices can choose the type of battery device according to their usage needs, such as individual battery cells, battery modules, or battery packs.

[0060] For ease of explanation, the following embodiments will use a vehicle as an example of an electrical device.

[0061] Figure 1 is a schematic diagram of the structure of a vehicle provided in some embodiments of this application.

[0062] As shown in Figure 1, a battery device 2 is installed inside the vehicle 1. The battery device 2 can be located at the bottom, front, or rear of the vehicle 1. The battery device 2 can be used to power the vehicle 1; for example, the battery device 2 can serve as the operating power source for the vehicle 1.

[0063] The vehicle 1 may also include a controller 3 and a motor 4. The controller 3 is used to control the battery device 2 to supply power to the motor 4, for example, for the power needs of the vehicle 1 during starting, navigation and driving.

[0064] In some embodiments, the battery device 2 can not only serve as the operating power source for the vehicle 1, but also as the driving power source for the vehicle 1, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1.

[0065] Figure 2 is an exploded view of a battery provided in some embodiments of this application. As shown in Figure 2, the battery device 2 includes a housing 5 and a battery cell (not shown), with the battery cell housed within the housing 5.

[0066] The housing 5 is used to house individual battery cells, and the housing 5 can have various structures. In some embodiments, the housing 5 may include a first housing portion 5a and a second housing portion 5b, which overlap each other, and together define a housing space 5c for housing the individual battery cells. The second housing portion 5b may be a hollow structure with one end open, and the first housing portion 5a may be a plate-like structure, with the first housing portion 5a covering the open side of the second housing portion 5b to form a housing 5 with the housing space 5c; alternatively, both the first housing portion 5a and the second housing portion 5b may be hollow structures with one side open, with the open side of the first housing portion 5a covering the open side of the second housing portion 5b to form a housing 5 with the housing space 5c. Of course, the first housing portion 5a and the second housing portion 5b can have various shapes, such as cylinders, cuboids, etc.

[0067] To improve the sealing performance after the first housing part 5a and the second housing part 5b are connected, a sealing element, such as sealant or sealing ring, can also be provided between the first housing part 5a and the second housing part 5b.

[0068] Assuming that the first box section 5a covers the top of the second box section 5b, the first box section 5a can also be called the upper box cover, and the second box section 5b can also be called the lower box.

[0069] In battery device 2, there can be one or more battery cells. If there are multiple battery cells, they can be connected in series, in parallel, or in a mixed configuration. A mixed configuration means that multiple battery cells are connected in both series and parallel configurations. Multiple battery cells can be directly connected in series, in parallel, or in a mixed configuration, and then the whole assembly of multiple battery cells is housed in housing 5. Alternatively, multiple battery cells can first be connected in series, in parallel, or in a mixed configuration to form battery module 6, and then multiple battery modules 6 can be connected in series, in parallel, or in a mixed configuration to form a whole assembly, which is then housed in housing 5.

[0070] Figure 3 is an exploded view of the battery module shown in Figure 2.

[0071] As shown in Figure 3, in some embodiments, there are multiple battery cells 7, which are first connected in series, parallel, or mixed to form a battery module 6. The multiple battery modules 6 are then connected in series, parallel, or mixed to form a whole and housed in a casing.

[0072] Multiple battery cells 7 in battery module 6 can be electrically connected through a busbar component to achieve parallel, series, or mixed connection of multiple battery cells 7 in battery module 6.

[0073] The battery cells mentioned in the embodiments of this application may include lithium-ion battery cells or sodium-ion battery cells.

[0074] Solid-state battery cells are battery cells that use solid electrolytes as the electrolyte material. A solid-state battery cell typically includes a casing and an electrode assembly housed within the casing. The electrode assembly generally includes a positive electrode, a negative electrode, and an electrolyte layer. The electrolyte layer, located between the positive and negative electrodes, serves to isolate the electrodes and transport active ions. The electrolyte layer consists of a solid electrolyte. Because solid-state battery cells do not contain liquid electrolytes, a certain amount of solid electrolyte is added to the positive electrode to improve the lithium-ion transport efficiency. Common solid electrolytes include inorganic solid electrolytes and polymer solid electrolytes. Inorganic solid electrolytes include halide solid electrolytes, oxide solid electrolytes, and sulfide solid electrolytes, among others.

[0075] Halogen solid electrolytes such as LiAlCl4 have low melting points and melt into a liquid state at around 200°C during preparation. After cooling to room temperature, the resulting solid electrolyte is brittle and has low ionic conductivity. The low ionic conductivity leads to poor lithium-ion transport efficiency. Furthermore, due to its high brittleness, its contact with the positive electrode active material is poor (solid-solid contact) when added to the positive electrode, which further deteriorates lithium-ion transport and thus affects the electrochemical performance of the solid-state battery cell.

[0076] In view of this, this application provides a halide oxide solid electrolyte. By introducing oxygen into the halide solid electrolyte for doping treatment, the ionic conductivity of the solid electrolyte can be improved. At the same time, doping can generate a certain amorphous phase in the halide oxide solid electrolyte, giving the halide oxide solid electrolyte a certain degree of viscoelasticity. This can improve the contact effect between the halide oxide solid electrolyte and the positive electrode active material, enhance the active ion transport efficiency, and thus improve the electrochemical performance of the solid battery cell.

[0077] [Halooxide solid electrolyte]

[0078] An embodiment of the first aspect of this application provides a halide oxide solid electrolyte, wherein the general formula of the halide oxide solid electrolyte is Li. a Al m X n Y b O c X includes trivalent metal elements other than Al, and Y includes halogens; 0 < a ≤ 9, 0 < m, 0 ≤ n, 0 < m + n ≤ 10, 0 < a / m ≤ 1, 0 < b ≤ 36, 0 < c ≤ 10; the crystal structure of the halide oxide solid electrolyte includes crystalline and amorphous phases, with the crystalline phase being the LiCl phase; the X-ray diffraction pattern of the halide oxide solid electrolyte shows diffraction peaks at positions of 31.62°-32.62°, 34.40°-35.40°, 49.64°-50.64°, and 59.25°-60.25°.

[0079] The halide oxide solid electrolyte provided in this application replaces part of the halogen by doping with oxygen. Since the Li-O bond has a lower bond energy than the Li-Cl bond, the oxygen doping can weaken the Coulomb interaction between Li and Cl, resulting in a faster migration rate of lithium ions in the lattice / amorphous network of the halide oxide solid electrolyte. This improves the ionic conductivity of the halide oxide solid electrolyte and thus improves the cycle performance of the solid-state battery. At the same time, doping can make the halide oxide solid electrolyte have both crystalline and amorphous phases. The presence of the amorphous phase can give the halide oxide solid electrolyte a certain degree of viscoelasticity, thereby improving the solid-solid contact effect between the halide oxide solid electrolyte and other materials (such as positive electrode active materials), further improving the lithium ion transport efficiency.

[0080] Figure 1 shows the X-ray diffraction (XRD) pattern of the halide oxide solid electrolyte in one embodiment of this application. It can be seen that, compared with the comparative example, the XRD pattern of the halide oxide solid electrolyte provided in this embodiment of the application only has a weak LiCl diffraction peak. This indicates that other elements such as Al and O in the halide oxide solid electrolyte provided in this embodiment of the application exist in the amorphous phase, and most of the halide oxide solid electrolyte is in the amorphous phase. This makes the halide oxide solid electrolyte have good viscoelasticity to improve its contact effect with the positive electrode active material, and can effectively improve the lithium ion diffusion rate.

[0081] In some embodiments, 4≤a≤9, 5≤m≤10, 5≤m+n≤10, 7≤b≤35, and 6≤c≤10.

[0082] According to the embodiments of this application, by keeping the proportions of each component in the halide oxide solid electrolyte within the above-mentioned range, it is beneficial to further adjust the structural composition of the halide oxide solid electrolyte, so that the halide oxide solid electrolyte has a suitable crystalline phase and amorphous phase, further improving the migration rate of lithium ions in the halide oxide solid electrolyte and improving the ionic conductivity of the halide oxide solid electrolyte.

[0083] In some embodiments, X may include one or more of Fe, In, Sb, and Bi.

[0084] In some embodiments, the glass transition temperature of the halide oxide solid electrolyte is -30°C to -10°C. As an example, the glass transition temperature of the halide oxide solid electrolyte is -30°C, -29°C, -28°C, -27°C, -26°C, -25°C, -24°C, -23°C, -22°C, -21°C, -20°C, -19°C, -18°C, -17°C, -16°C, -15°C, -14°C, -13°C, -12°C, -11°C, -10°C, or any combination of the above numbers, and may be selected as -20°C to -15°C.

[0085] The glass transition temperature of a halide oxide solid electrolyte refers to the temperature at which the halide oxide solid electrolyte changes from a glassy state to a rubbery state. By keeping the glass transition temperature of the halide oxide solid electrolyte within the above range, the halide oxide solid electrolyte can change to a rubbery state at room temperature. In this state, the halide oxide solid electrolyte can have good viscoelasticity, which can improve its deformability and solve the problem of poor contact between the halide oxide solid electrolyte and the positive electrode active material, thereby improving the transport efficiency of active ions and improving the electrochemical performance of solid-state battery cells.

[0086] The glass transition temperature of halide oxide solid electrolytes can be measured using instruments and methods known in the art. For example, differential scanning calorimetry (DSC) can be used. The specific heat capacity changes significantly before and after the glass transition temperature, and the glass transition temperature can be determined from the DSC curve. The glass transition temperature is typically a step in the endothermic direction, and the glass transition is a region. This method usually uses the intersection of the curve with a line equidistant from two extrapolated baselines as the glass transition temperature.

[0087] In some embodiments, the melting temperature of the halide oxide solid electrolyte can be 60°C-260°C. For example, the melting temperature of the halide oxide solid electrolyte can be 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, 170°C, 180°C, 190°C, 200°C, 210°C, 220°C, 230°C, 240°C, 250°C, 260°C, or any range of the above values. Optionally, the melting temperature of the halide oxide solid electrolyte can be 80°C-220°C.

[0088] In this application, the melting temperature of the halide oxide solid electrolyte refers to the temperature at which the halide oxide solid electrolyte is heated to a molten state. The positive electrode in this application may include the halide oxide solid electrolyte provided in the first aspect embodiment. By keeping the melting temperature of the halide oxide solid electrolyte within the aforementioned range, the halide oxide solid electrolyte can be heated to a molten state and dispersed in the positive electrode. This improves the contact between the halide oxide solid electrolyte and the active components of the positive electrode, reducing the contact gap. Simultaneously, dispersing the halide oxide solid electrolyte in the positive electrode at the aforementioned temperature reduces the structural damage to the active material of the positive electrode caused by high temperatures, thus improving the structural stability of the positive electrode.

[0089] The melting temperature of halide oxide solid electrolytes can be determined using methods and instruments known in the art. For example, differential scanning calorimetry (DSC) can be used. During the melting process, halide oxide solid electrolytes undergo significant melting, and the DSC curve will show a sharp peak at the melting temperature; this peak value is the melting temperature of the halide oxide solid electrolyte. Because halide oxide solid electrolytes have a certain amorphous state, their melting temperature has a certain range.

[0090] In some embodiments, the ionic conductivity of the halide oxide solid electrolyte can be 1 × 10⁻⁶. -4 mS / cm to 1×10 - 2 mS / cm. As an example, the ionic conductivity of halide oxide solid electrolytes can be 1 × 10⁻⁶ mS / cm. -4 mS / cm, 1×10 - 3 mS / cm, 1×10 -2 mS / cm, or any range of the above values.

[0091] According to the embodiments of this application, by making the ionic conductivity of the halide oxide solid electrolyte within the above-mentioned range, the halide oxide solid electrolyte can have high ion transport characteristics, which is beneficial to further improve the electrochemical performance of solid-state battery cells.

[0092] The ionic conductivity of halide oxide solid electrolytes has a well-known meaning in the art and can be measured using methods and instruments known in the art. For example, electrochemical impedance spectroscopy can be used. A certain amount (e.g., 120 mg) of halide oxide solid electrolyte is placed in a mold and pressed under a certain pressure (e.g., 360 MPa). Then, a lithium metal symmetric battery is assembled according to the structure of "blocking electrode-halide oxide solid electrolyte-blocking electrode". The blocking electrode can be a carbon electrode. The ionic conductivity is tested and calculated. The test frequency range can be 1 Hz-1 MHz, the amplitude can be 10 mV, and the test temperature is 25 °C.

[0093] [Preparation methods of halide oxide solid electrolytes]

[0094] An embodiment of the second aspect of this application provides a method for preparing a halide oxide solid electrolyte, comprising the following steps:

[0095] Step S100, according to the chemical formula Li a Al m X n Y b O cProvide raw materials including lithium source, aluminum source, X element source, Y element source and oxygen source, where X includes trivalent metal elements other than Al, Y includes halogens; 0<a≤9, 0<m, 0≤n, 0<m+n≤10, 0<a / m≤1, 0<b≤36, 0<c≤10;

[0096] Step S200: The lithium source, aluminum source, X element source and Y element source are mixed and subjected to a first heat treatment to obtain the precursor;

[0097] In step S300, the precursor is mixed with an oxygen source and subjected to a second heat treatment to obtain a halide oxide solid electrolyte. The crystal structure of the halide oxide solid electrolyte includes a crystalline phase and an amorphous phase, with the crystalline phase being the LiCl phase. The X-ray diffraction pattern of the halide oxide solid electrolyte shows diffraction peaks at positions of 31.62°-32.62°, 34.40°-35.40°, 49.64°-50.64°, and 59.25°-60.25°.

[0098] The oxygen source includes crystalline hydrates, whose melting point is lower than the temperature of the second heat treatment.

[0099] The method for preparing halide oxide solid electrolytes provided in this application uses crystalline hydrates as an oxygen source to provide oxygen for doping during the preparation process. The crystalline hydrates can provide oxygen during low-temperature decomposition, and the low-temperature decomposition characteristics of crystalline hydrates are conducive to the formation of a more porous polyanion cluster environment. This generates weak LiCl crystalline and amorphous phases in the halide oxide solid electrolyte, weakening the Coulomb interaction between Li and Cl, and enabling lithium ions to have a faster migration rate in the lattice / amorphous network, thereby improving the ionic conductivity of the halide oxide solid electrolyte.

[0100] The method for preparing halide oxide solid electrolytes provided in this application embodiment can synthesize oxygen-free Li during the first heat treatment process. a Al m X n Y b In this step, a precursor forms a crystalline phase. In step S200, oxygen is introduced, but it does not participate in the formation of the crystalline phase, only forming an amorphous phase. This allows for better control of the amorphous phase content in the halide oxide solid electrolyte, which is beneficial for further improving the viscoelasticity of the halide oxide solid electrolyte. Furthermore, using crystalline hydrate as the oxygen source and employing two heat treatments during the preparation process for the synthesis of the halide oxide solid electrolyte eliminates the traditional ball milling mixing step. This facilitates the rapid synthesis of halide oxide solid electrolytes containing both crystalline and amorphous phases, reducing production costs and improving production efficiency.

[0101] In some embodiments, the temperature of the first heat treatment can be 150°C-300°C. As an example, the temperature of the first heat treatment can be 150°C, 160°C, 170°C, 180°C, 190°C, 200°C, 210°C, 220°C, 230°C, 240°C, 250°C, 260°C, 270°C, 280°C, 290°C, 300°C, or any range of the above values, and can be selected as 180°C-260°C.

[0102] In some embodiments, the time for the first heat treatment can be 3h-1h, for example, 3h, 4h, 5h, 6h, 7h, 8h, 9h, 10h, or any range of the above values.

[0103] In some embodiments, the temperature of the second heat treatment can be 200℃-300℃. As an example, the temperature of the second heat treatment can be 200℃, 210℃, 220℃, 230℃, 240℃, 250℃, 260℃, 270℃, 280℃, 290℃, 300℃, or any range of the above values, and can be selected as 220℃-280℃.

[0104] In some embodiments, the duration of the second heat treatment can be 0.5h-5h. As an example, the duration of the second heat treatment can be 0.5h, 1.0h, 1.5h, 2.0h, 2.5h, 3.0h, 3.5h, 4.0h, 4.5h, 5.0h, or any range of the above values.

[0105] According to the embodiments of this application, by keeping the temperature and time of the first heat treatment and the second heat treatment within the above-mentioned range, it is beneficial to simultaneously form crystalline and amorphous phases in the solid electrolyte and control the content of crystalline and amorphous phases within a suitable range, thereby further improving the ionic conductivity of the solid electrolyte.

[0106] In some embodiments, the crystalline hydrate may include one or more of AlCl3·6H2O, FeCl3·6H2O, CrCl3·6H2O, InCl3·4H2O, and YCl3·6H2O.

[0107] In some embodiments, the lithium source may include one or more lithium-containing compounds, optionally lithium-containing halides.

[0108] In some embodiments, the aluminum source may include one or more aluminum-containing compounds, optionally aluminum halides.

[0109] In some embodiments, the source of element X may include one or more compounds containing element X, optionally in the form of halides containing element X. Element X includes trivalent metal elements other than Al, and may be one or more of Fe, In, Sb, and Bi.

[0110] In some embodiments, the lithium source, aluminum source, and X element source each independently include their respective anhydrous halides. This reduces the introduction of impurity elements during the preparation of halide oxide solid electrolytes. Furthermore, since the lithium source, aluminum source, and X element source are free of water of crystallization, the introduction of oxygen in step S200 can be avoided. This facilitates control over the structural composition of the resulting halide oxide solid electrolyte, resulting in a higher proportion of amorphous phases.

[0111] [positive electrode]

[0112] The positive electrode includes a positive current collector and a positive electrode film layer located on at least one side of the current collector, the positive electrode film layer including a positive electrode active material.

[0113] As an example, the current collector has two surfaces opposite each other in its own thickness direction, and the positive electrode film layer is disposed on either or both of the two opposite surfaces of the current collector.

[0114] In some embodiments, the positive electrode active material may include one or more of lithium phosphate and layered lithium transition metal oxides.

[0115] Lithium-containing phosphates may include one or more of lithium iron phosphate, lithium manganese phosphate, lithium manganese iron phosphate, and their respective modified compounds.

[0116] Examples of layered lithium-containing transition metal oxides may include one or more of lithium cobalt oxides, lithium nickel oxides, lithium manganese oxides, lithium nickel cobalt oxides, lithium manganese cobalt oxides, lithium nickel manganese oxides, lithium nickel cobalt manganese oxides, lithium nickel cobalt aluminum oxides, and their respective modified compounds.

[0117] In some embodiments, the layered lithium-containing transition metal oxide may include Ni. The molar amount of Ni may account for more than 70% of the total molar amount of transition metal elements in the layered lithium-containing transition metal oxide; optionally, the molar amount of Ni may account for more than 80% of the total molar amount of transition metal elements in the layered lithium-containing transition metal oxide; more preferably, the molar amount of Ni may account for more than 90% of the total molar amount of transition metal elements in the layered lithium-containing transition metal oxide.

[0118] The higher the Ni content in layered lithium-containing transition metal oxides, the higher the energy density of the battery cell.

[0119] In some embodiments, layered lithium-containing transition metal oxides may include Li a Ni b Co c M d O e A fWherein, 0 < a ≤ 1.2; 0.8 ≤ b < 1; 0 < c < 1; 0 < d < 1; b + c + d = 1; 1 ≤ e ≤ 2; 0 ≤ f ≤ 1; M includes, but is not limited to, one or more of Mn, Al, Zr, Zn, Cu, Cr, Mg, Fe, V, Ti, and B; A includes, but is not limited to, one or more of N, F, S, and Cl. This can further improve the energy density of individual battery cells.

[0120] In some embodiments, as an example, layered lithium-containing transition metal oxides may include, but are not limited to, LiNi. 0.8 Co 0.1 Mn 0.1 O2, LiNi 0.8 Co 0.15 Al 0.05 O2, LiNi 0.9 Co 0.06 Mn 0.04 O2, LiNi 0.92 Co 0.06 Mn 0.02 O2, LiNi 0.96 Co 0.02 Mn 0.02 O2, LiNi 0.96 Co 0.02 Mn 0.02 O2N 0.02 One or more of them.

[0121] During the charging and discharging process of a battery cell, Li undergoes insertion / extraction and consumption, resulting in varying molar Li content at different discharge states. In the examples of positive electrode active materials in this application, the molar Li content refers to the initial state of the material, i.e., the state before feeding. After charge-discharge cycles, the molar Li content may change when the positive electrode active material is applied to the battery cell.

[0122] In the examples of positive electrode active materials in this application, the molar content of O is only a theoretical value. Oxygen release from the crystal lattice will cause the molar content of O to change, and the actual molar content of O will fluctuate.

[0123] The modified compounds for the above-mentioned positive electrode active materials can be obtained by doping and / or surface coating of the positive electrode active materials.

[0124] In some embodiments, the positive electrode film layer may optionally include a binder. As an example, the binder may include one or more of polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), PVDF-tetrafluoroethylene-propylene terpolymer, PVDF-hexafluoropropylene-tetrafluoroethylene terpolymer, tetrafluoroethylene-hexafluoropropylene copolymer, and fluorinated acrylate resins.

[0125] In some implementations, the weight percentage of the binder in the positive electrode film layer is greater than or equal to 0.5%, which is beneficial for obtaining good adhesion performance.

[0126] In some embodiments, the positive electrode film layer further includes a conductive agent. As an example, the conductive agent may include one or more of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.

[0127] In some embodiments, the positive electrode film layer further includes a solid electrolyte.

[0128] Solid electrolytes may include the halide oxide solid electrolytes provided in the first aspect of this application or halide oxide solid electrolytes obtained according to the preparation method provided in the second aspect of this application.

[0129] In some embodiments, based on the total mass of the positive electrode film, the mass percentage of the halide oxide solid electrolyte in the positive electrode film can be 5%-35%, for example, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, or any range of the above values, and can be selected as 10%-32%.

[0130] In some embodiments, the current collector serving as the positive electrode may also be a metal foil or a composite current collector. For example, aluminum foil may be used as the metal foil. The composite current collector may include a polymer material substrate and a metal layer formed on at least one surface of the polymer material substrate. The composite current collector can be made by forming a metal material, such as aluminum, aluminum alloy, copper, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, on the polymer material substrate. The polymer material substrate may include polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), polyethylene (PE), and other substrates.

[0131] In some embodiments, the thickness of the positive current collector is from 4 μm to 20 μm. It is optionally from 6 μm to 18 μm, and more preferably from 8 μm to 16 μm.

[0132] [negative electrode]

[0133] The negative electrode includes a negative electrode current collector and a negative electrode film layer located on at least one side of the negative electrode current collector. The negative electrode film layer may include a negative electrode active material.

[0134] As an example, the negative electrode active material may include one or more of the following: artificial graphite, natural graphite, mesophase micro carbon spheres, hard carbon, soft carbon, silicon, and silicon-carbon composites.

[0135] Silicon-based composite materials can be prepared by methods known in the art. For example, they can be prepared by vapor deposition using graphite and silicon materials as raw materials.

[0136] In some embodiments, the negative electrode active material may further include one or more of Li, Sn, Zn, In and their alloys.

[0137] In some embodiments, the negative electrode film layer may further include a negative electrode conductive agent. As an example, the negative electrode conductive agent may include, but is not limited to, one or more of superconducting carbon, conductive graphite, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.

[0138] In some embodiments, the negative electrode film layer may also include other additives. As an example, other additives may include thickeners, such as sodium carboxymethyl cellulose (CMC-Na), PTC thermistor materials, etc.

[0139] In some embodiments, the negative electrode current collector may be a metal foil or a composite current collector. Examples of metal foils include copper foil, copper alloy foil, aluminum foil, and aluminum alloy foil. The composite current collector may include a polymeric material substrate and a metal material layer formed on at least one side of the polymeric material substrate. Examples of metal materials include, but are not limited to, one or more of copper, copper alloys, nickel, nickel alloys, titanium, titanium alloys, silver, and silver alloys. Examples of polymeric material substrates include, but are not limited to, one or more of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), and polyethylene (PE).

[0140] The negative electrode does not exclude other additional functional layers besides the negative electrode film layer. For example, in some embodiments, the negative electrode may also include a conductive undercoat layer sandwiched between the negative electrode current collector and the negative electrode film layer and located on the surface of the negative electrode current collector, which may be composed of a conductive agent and an adhesive; in some embodiments, the negative electrode may also include a protective layer covering the surface of the negative electrode film layer.

[0141] In some embodiments, the battery cell can be a negative electrode-free battery cell, in which case no negative electrode film layer containing a negative electrode active material layer is disposed on the negative electrode current collector. When the battery cell is a negative electrode-free battery cell, a functional layer for depositing lithium metal can be disposed on the surface of the negative electrode current collector. The material of the functional layer can include a metallic material, such as an elemental metal or an alloy. The type of metallic material can be any type known in the art that can serve as a negative electrode functional layer in a negative electrode-free battery cell, and this application does not limit this.

[0142] [Electrolyte layer]

[0143] The electrolyte layer includes a solid electrolyte.

[0144] Solid electrolytes may include halide oxide solid electrolytes according to the first aspect of this application or halide oxide solid electrolytes prepared according to the preparation method of the second aspect of this application.

[0145] In some embodiments, the solid electrolyte may also include one or more of the following: sulfide solid electrolytes, oxide solid electrolytes, halide solid electrolytes, and organic solid electrolytes, which are different from the halide oxide solid electrolytes of the first aspect of this application.

[0146] Sulfide solid electrolytes have high 10 -2 S / cm to 10 -3 A lithium-ion conductivity of S / cm facilitates the formation of contact interfaces between electrodes and exhibits high mechanical strength and flexibility. In this application embodiment, there are no particular limitations on the type of sulfide-based solid electrolyte, and all known sulfide materials used in the battery field are acceptable. In this application embodiment, the sulfide-based solid electrolyte may include Li6PS5Cl (LPSCl), Thio-LISICON (Li 3.25 Ge 0.25 P 0.75 S4), Li2S-P2S5-LiCl, Li2S-SiS2, LiI-Li2S-SiS2, LiI-Li2S-P2S5, LiI-Li2S-P2O5, LiI-Li3PO4-P2S5, Li2S-P2S5, Li3PS4, Li7P3S 11 , LiI-Li2S-B2S3, Li3PO4-Li2S-Si2S, Li3PO4-Li2S-SiS2, LiPO4-Li2S-SiS, Li 10 GeP2S 12 Li 9.54 Si 1.74 P 1.44 S 11.7 Cl 0.3 and Li7P3S 11 One or more of them.

[0147] Oxide-based solid electrolytes exhibit high safety in air and have a 10 -3 S / cm to 10 -4The lithium-ion conductivity (S / cm) is lower than that of sulfide-based solid electrolytes, but relatively higher. Furthermore, oxide-based solid electrolytes exhibit high electrochemical safety and mechanical strength. However, oxide-based solid electrolytes have high oxidation voltage. Additionally, solid electrolytes have high grain boundary resistance, making it difficult to form a contact interface between the electrode and electrolyte, requiring high-temperature heat treatment processes of 1000 kJ or higher, and are difficult to scale up. In the embodiments of this application, the oxide-based solid electrolyte can be any known oxide material used in the field of lithium batteries. In the embodiments of this application, the oxide-based solid electrolyte includes perovskite solid electrolyte, sodium superionic conductor solid electrolyte (NASICON), lithium superionic conductor solid electrolyte (LISICON), and lithium lanthanum zirconium oxide solid electrolyte (LLZO).

[0148] Organic solid electrolytes (OSEs) are a type of solid electrolyte. OSEs can readily form electrode interfaces and minimize dendrite growth, thus ensuring stable reactions between OSEs and lithium metal. The disadvantages of OSEs are their relatively low lithium-ion conductivity and the fact that they typically require high-temperature operation. In this embodiment, the OSE comprises polyethylene oxide (PEO).

[0149] The thickness of the electrolyte layer can be selected differently depending on the desired properties of the solid-state battery. Specifically, in some embodiments, the thickness of the electrolyte layer can be from 0.1 μm to 1000 μm; in other embodiments, the thickness of the electrolyte layer can be from 1 μm to 500 μm; in still other embodiments, the thickness of the electrolyte layer can be from 20 μm to 30 μm; this application does not limit it in this regard.

[0150] For ease of subsequent description and understanding, the preparation method of the battery cell and the battery cell in the embodiments of this application can use sulfide-based solid electrolytes.

[0151] Example

[0152] The following embodiments describe the disclosure of this application in more detail. These embodiments are merely illustrative, as various modifications and variations will be apparent to those skilled in the art within the scope of the disclosure of this application. Unless otherwise stated, all parts, percentages, and ratios reported in the following embodiments are based on mass, and all reagents used in the embodiments are commercially available or synthesized by conventional methods and can be used directly without further processing, and the instruments used in the embodiments are commercially available.

[0153] Example 1

[0154] Preparation of halide oxide solid electrolytes

[0155] Anhydrous lithium chloride (LiCl) and anhydrous aluminum chloride (AlCl3) were mixed evenly in a mortar at a molar ratio of 1:1, and then added to an alumina crucible. The mixture was heated to 200°C in an argon atmosphere and kept at that temperature for 5 hours to obtain the precursor LiAlCl4.

[0156] The precursor and AlCl3·6H2O were added to an alumina crucible at a molar ratio of 4:1, and heated to 250℃ under an argon atmosphere and held for 1 h to obtain the halide oxide solid electrolyte Li4Al5Cl7O6.

[0157] Preparation of solid-state battery cells

[0158] LiNi, the positive electrode active material 0.8 Co 0.1 Mn 0.1 O2, the halide oxide solid electrolyte LiAlCl4O prepared above 0.75 The conductive agent carbon black is added to a mortar and ground for 30 minutes at a mass ratio of 70:27:3 to obtain a positive electrode powder.

[0159] The sulfide solid electrolyte Li7PS5Cl1 was cold-pressed into a sheet at a pressure of 2t to obtain an electrolyte layer. Then, the above-mentioned positive electrode powder was uniformly covered on one side of the electrolyte layer and held at a pressure of 4t for 10 minutes. Then, composite indium sheet and composite copper-lithium sheet were attached to the other side of the electrolyte layer. Finally, the solid battery cell was compacted in a mold at a pressure of 360MPa to obtain a solid battery cell.

[0160] Examples 2-5

[0161] The preparation method of the solid-state battery cell is similar to that in Example 1, except that the parameters of the halide oxide solid electrolyte are adjusted. The specific parameter adjustments are shown in Table 1.

[0162] Comparative Examples 1 to 2

[0163] The preparation method of the solid-state battery cell is similar to that in Example 1, except that the parameters of the halide oxide solid electrolyte are adjusted. The specific parameter adjustments are shown in Table 1.

[0164] Table 1

[0165] Examples 6 to 9

[0166] The preparation method of the solid-state battery cell is similar to that in Example 1, except that the preparation parameters of the halide oxide solid electrolyte are adjusted. For details of the parameter adjustments, please refer to Table 2.

[0167] Table 2

[0168] Comparative Example 3

[0169] The preparation method of the solid-state battery cell is similar to that in Example 1, except that the preparation method of the halide oxide solid electrolyte is adjusted, as follows:

[0170] Anhydrous lithium chloride (LiCl), anhydrous aluminum chloride (AlCl3), and aluminum chloride hexahydrate (AlCl3·6H2O) were mixed evenly in a mortar at a molar ratio of 4:4:1, and then added to an alumina crucible. The mixture was heated to 200°C in an argon atmosphere and kept at that temperature for 5 hours to obtain a halide oxide solid electrolyte.

[0171] Test section

[0172] 1. Ionic conductivity of halide oxide solid electrolytes

[0173] A solid halide oxide electrolyte was placed in a mold and pressed at 360 MPa and 550 °C. A symmetrical cell was assembled using carbon powder as a blocking electrode, following a "blocking electrode-electrolyte layer-blocking electrode" structure. Electrochemical impedance spectroscopy was performed, and the ionic conductivity was calculated. The test frequency range was 1 Hz-1 MHz, the amplitude was 10 mV, and the test temperature was 25 °C. The impedance R of the solid halide oxide electrolyte was obtained according to the formula: The ionic conductivity of halide oxide solid electrolytes can be calculated, where L is the thickness of the electrolyte layer and S is the cross-sectional area of ​​the electrolyte layer.

[0174] 2. Electrochemical performance of solid-state battery cells

[0175] At 25°C, the assembled solid-state battery cell was charged to 3.68V (4.3V for lithium) at a current density of 0.1C, left to stand for 10 minutes, and then discharged to 1.98V (2.6V for lithium) at a current density of 0.1C to obtain the first discharge capacity C0 of the battery; the solid-state battery cell was charged and discharged according to the above scheme, and the discharge capacity of the nth cycle was recorded as Cn;

[0176] The ratio of the first-cycle discharge capacity C0 of a solid-state battery cell to the weight of the positive electrode active material is used as the first-cycle discharge capacity (mAh / g) of the solid-state battery cell.

[0177] The first charge-discharge efficiency (%) of a solid-state battery cell = C0 / D0 × 100%;

[0178] n-cycle capacity retention rate (%) = Cn / C0 × 100%.

[0179] The test results are detailed in Table 3.

[0180] Table 3

[0181] Based on the data in Tables 1 to 3, this application embodiment uses low-melting-point crystalline hydrates as oxygen sources to introduce oxygen elements into the halide solid electrolyte. Through the adjustment period preparation method, the prepared halide oxide solid electrolyte has high ionic conductivity and generates more amorphous phases, thereby giving the halide oxide solid electrolyte a certain degree of viscoelasticity. This improves the lithium-ion transport rate and thus improves the electrochemical performance of solid-state battery cells.

[0182] It should be noted that this application is not limited to the above-described embodiments. The above embodiments are merely examples, and any embodiments with the same structure and effect as the technical concept within the scope of this application are included in the technical scope of this application. Furthermore, various modifications that can be conceived by those skilled in the art to the embodiments, and other ways of constructing by combining some of the constituent elements of the embodiments, without departing from the spirit of this application, are also included in the scope of this application.

Claims

1. A solid-state battery cell, comprising a positive electrode, a negative electrode, and an electrolyte layer, wherein the electrolyte layer is located between the positive electrode and the negative electrode, and the positive electrode comprises a halide oxide solid electrolyte; The halide solid-state electrolyte has a general formula of Li a Al m X n Y b O c , X includes a trivalent metal element other than Al, Y includes a halogen; 0 The crystal structure of the halide oxide solid electrolyte includes a crystalline phase and an amorphous phase. The crystalline phase is the LiCl phase. The X-ray diffraction pattern of the halide oxide solid electrolyte has diffraction peaks at positions of 31.62°-32.62°, 34.40°-35.40°, 49.64°-50.64°, and 59.25°-60.25°.

2. The solid-state battery cell of claim 1, wherein, 4≤a≤9, 5≤m≤10, 5≤m+n≤9, 7≤b≤35, 6≤c≤10.

3. The solid-state battery cell of claim 1 or 2, wherein, X includes one or more of Fe, In, Sb, and Bi.

4. The solid-state battery cell of any one of claims 1-3, wherein, The glass transition temperature of the halide oxide solid electrolyte is -30°C to -10°C.

5. The solid state battery cell of claim 4, wherein, The glass transition temperature of the halide oxide solid electrolyte is -20°C to -15°C.

6. The solid-state battery cell of claim 4 or 5, wherein, The melting temperature of the halide oxide solid electrolyte is 60°C to 260°C.

7. The solid-state battery cell of any one of claims 1-6, wherein, The oxyhalide solid state electrolyte has an ionic conductivity of 1 x 10 -4 mS / cm to 1 x 10 -2 mS / cm at 25°C.

8. The solid-state battery cell of any one of claims 1-7, wherein, The positive electrode includes a positive current collector and a positive electrode film layer located on at least one side of the positive current collector, the positive electrode film layer including the halide oxide solid electrolyte; based on the total mass of the positive electrode film layer, the mass percentage of the solid electrolyte is 5%-35%.

9. A battery device comprising a solid-state battery cell according to any one of claims 1-8.

10. An electrical device comprising a solid-state battery cell according to any one of claims 1-8 or a battery device according to claim 9.

11. A halide oxide solid state electrolyte having the general formula Li a Al m X n Y b O c wherein, X includes trivalent metal elements other than Al, and Y is a halogen; 0<a≤9, 0<m, 0≤n, 0<m+n≤10, 0<a / m≤1, 0<b≤36, 0<c≤10; The crystal structure of the halide oxide solid electrolyte includes a crystalline phase and an amorphous phase. The crystalline phase is the LiCl phase. The X-ray diffraction pattern of the halide oxide solid electrolyte has diffraction peaks at positions of 31.62°-32.62°, 34.40°-35.40°, 49.64°-50.64°, and 59.25°-60.25°.

12. A method for preparing a halide oxide solid electrolyte, comprising the following steps: According to the chemical formula Li a Al m X n Y b O c A raw material comprising a lithium source, an aluminum source, an X element source, a halogen source, and an oxygen source is provided, wherein X includes a trivalent metal element other than Al, Y includes a halogen; 0 The lithium source, aluminum source, X element source and halogen source are mixed and subjected to a first heat treatment to obtain a precursor. The precursor is mixed with the oxygen source and subjected to a second heat treatment to obtain a halide oxide solid electrolyte. The crystal structure of the halide oxide solid electrolyte includes a crystalline phase and an amorphous phase. The crystalline phase is the LiCl phase. The X-ray diffraction pattern of the halide oxide solid electrolyte has diffraction peaks at positions of 31.62°-32.62°, 34.40°-35.40°, 49.64°-50.64°, and 59.25°-60.25°. The oxygen source includes a crystalline hydrate, the melting point of which is lower than the temperature of the second heat treatment.

13. The method of making according to claim 12, wherein, The crystalline hydrate includes one or more of AlCl3·6H2O, FeCl3·6H2O, CrCl3·6H2O, InCl3·4H2O, and YCl3·6H2O.

14. The production method according to claim 12 or 13, wherein The lithium source, the aluminum source, and the X element source are all anhydrous compounds; wherein... The lithium source includes lithium-containing halides; and / or The aluminum source includes aluminum halide; and / or The source of element X includes halides containing element X.

15. The method of manufacturing according to any one of claims 12-14, wherein, The preparation method satisfies at least one of the following conditions: (1) The temperature of the first heat treatment is 150℃-300℃; (2) The duration of the first heat treatment is 3-10 hours; (3) The temperature of the second heat treatment is 200℃-300℃; (4) The second heat treatment time is 0.5h-5h.

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