Solid-state battery, halide solid electrolyte, and electric device

Abstract

The present application provides a solid-state battery, a halide solid electrolyte and an electric device, the solid-state battery comprising a cathode sheet, the cathode sheet comprising a cathode active material layer, the cathode active material layer comprising a cathode active material and a halide solid electrolyte; the cathode active material comprising a high-voltage material, the highest charge cut-off voltage of the high-voltage material being greater than or equal to 4.3 V; the halide solid electrolyte comprising one or more of compounds satisfying the chemical formula Li 3‑2a‑b A a B b C c D d E e O n Cl 6‑m‑2n F m , wherein A comprises one or more of Ta, Nb and V, B comprises one or both of Zr and Hf, C, D, E each independently comprises a trivalent metal element, 0

Description

Technical Field

[0001] This application relates to the field of electrochemistry technology, and in particular, to a solid-state battery, a halide solid electrolyte, and an electrical device. Background Art

[0002] The solid-state battery uses a non-flammable solid electrolyte to replace the organic electrolyte in the traditional liquid secondary battery, greatly improving the safety of the battery. It is considered to be the new generation of battery closest to industrialization. However, in the solid-state battery, the interface compatibility is poor, resulting in an unsatisfactory cycle performance of the battery. Summary of the Invention

[0003] In view of the above problems, this application provides a solid-state battery, a halide solid electrolyte, and an electrical device, and the solid-state battery has improved cycle performance.

[0004] To achieve the above object, a first aspect of this application provides a solid-state battery, including a positive electrode sheet, the positive electrode sheet includes a positive electrode active material layer, and the positive electrode active material layer contains a positive electrode active material and a halide solid electrolyte;

[0005] The positive electrode active material includes a high-voltage material, and the highest charging cut-off voltage of the high-voltage material is greater than or equal to 4.3V;

[0006] The halide solid electrolyte includes one or more of the compounds satisfying the chemical formula Li 3-2a-b A a B b C c D d E e O n Cl 6-m-2n F m wherein, A includes one or more of Ta, Nb, and V, B includes one or two of Zr and Hf, C, D, and E each independently include a trivalent metal element, 0 < a ≤ 0.6, 0 < b ≤ 0.6, 0 < c < 0.3, 0 < d < 0.3, 0 < e < 0.3, c = d = e, 0 ≤ n ≤ 0.5, and the value of m makes the algebraic sum of the valence of the compound zero.

[0007] The solid-state battery provided by the present application adds a halide solid electrolyte satisfying the foregoing chemical formula to the positive electrode active material layer, that is, a high-voltage material and the halide solid electrolyte are used in combination in the positive electrode active material layer. Since the halide solid electrolyte satisfying this chemical formula has more lattice distortions and higher structural disorder inside, when cycling at a high voltage, it can effectively promote the activation of lithium ions, reduce the ion transport impedance between the positive electrode layer and the solid electrolyte layer, improve the ion transport rate, effectively improve the interfacial compatibility between the solid electrolyte layer and the positive electrode layer, and improve the cycle performance and rate performance of the battery.

[0008] In some embodiments, one or more of the following conditions are satisfied:

[0009] (1) The maximum charge cut-off voltage of the high-voltage material is 4.3V - 4.8V;

[0010] (2) C, D, and E each independently include one or more of Sc, Y, La, Ce, Nd, Pm, Sm, Ho, Er, Yb, Al, and In.

[0011] In some embodiments, 0 < n ≤ 0.5.

[0012] In some embodiments, 0.1 ≤ n ≤ 0.5.

[0013] In some embodiments, the halide solid electrolyte includes one or more of the compounds satisfying the chemical formula Li 3-2a- b A a Zr b In c D d E e O n Cl 6-m-2n F m ;

[0014] Wherein, A is one or both of Ta and Nb, D and E each independently are one or more of Y, Er, Yb, and Ho, 0.3 ≤ a ≤ 0.6, 0.2 ≤ b ≤ 0.6, 0 < c < 0.3, 0 < d < 0.3, 0 < e < 0.3, c = d = e, 0.25 ≤ n ≤ 0.5, and the value of m makes the algebraic sum of the valences of the compound zero.

[0015] In some embodiments, the positive electrode active material includes one or more of lithium nickel cobalt manganese oxide and lithium-rich manganese-based oxide, and the lithium nickel cobalt manganese oxide satisfies the chemical formula LiNi x Co y Mn 1-x-yO2, where 0.8 < x < 1 and 0 < y < 0.1; the lithium-rich manganese-based oxide satisfies the chemical formula x’Li2MnO3·(1 - x’)LiMO2, where M includes transition metal elements and 0 < x’ < 1.

[0016] In some embodiments, one or more of the following conditions are satisfied:

[0017] (1) 0.83 ≤ x ≤ 0.98;

[0018] (2) 0.35 ≤ x’ ≤ 0.75.

[0019] In some embodiments, the lithium nickel cobalt manganese oxide includes one or more of LiNi 0.83 Co 0.07 Mn 0.08 O2, LiNi 0.90 Co 0.05 Mn 0.05 O2, LiNi 0.94 Co 0.03 Mn 0.03 O2, and LiNi 0.96 Co 0.02 Mn 0.02 O2.

[0020] In some embodiments, the lithium-rich manganese-based oxide includes one or more of 0.45Li2MnO3·0.55LiNiO2, 0.55Li2MnO3·0.45LiNiO2, 0.55Li2MnO3·0.45LiCoO2, and 0.35Li2MnO3·0.75LiMnO2.

[0021] In some embodiments, the average particle size of the halide solid electrolyte is 0.3 μm to 10 μm.

[0022] In some embodiments, the average particle size of the halide solid electrolyte is 0.3 μm to 2 μm.

[0023] In some embodiments, the mass ratio of the positive electrode active material to the halide solid electrolyte is (60 - 80):(37 - 17).

[0024] In some embodiments, the positive electrode active material layer further includes a conductive agent, and the mass ratio of the conductive agent to the positive electrode active material is 3:(60 - 80).

[0025] In some embodiments, the solid-state battery further includes a solid electrolyte layer, and the solid electrolyte layer contains a sulfide solid electrolyte.

[0026] In some of these embodiments, the solid-state battery is an all-solid-state battery.

[0027] A second aspect of the present application provides a halide solid electrolyte, which includes one or more compounds satisfying the chemical formula Li 3-2a-b A a B b C c D d E e O n Cl 6-m-2n F m ;

[0028] wherein, A includes one or more of Ta, Nb, and V, B includes one or two of Zr and Hf, C, D, and E are each independently a trivalent metal element, 0 < a ≤ 0.6, 0 < b ≤ 0.6, 0 < c < 0.3, 0 < d < 0.3, 0 < e < 0.3, c = d = e, 0 ≤ n ≤ 0.5, and the value of m makes the algebraic sum of the valence of the compound zero.

[0029] In some of these embodiments, the halide solid electrolyte is the halide solid electrolyte in the solid-state battery described in the first aspect of the present application.

[0030] A third aspect of the present application provides an electrical device, including the solid-state battery described in the first aspect of the present application.

[0031] Details of one or more embodiments of the present application are set forth in the following drawings and description. Other features, objects, and advantages of the present application will become apparent from the specification, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] To better describe and illustrate the embodiments or examples provided by the present application, one or more drawings may be referred to. Additional details or examples used to describe the drawings should not be considered as limiting the scope of any of the disclosed applications, the currently described embodiments or examples, or the currently understood best mode of these applications. Moreover, in all the drawings, the same reference numerals are used to denote the same components. In the drawings:

[0033] Figure 1 is the X-ray diffraction pattern of the halide solid electrolyte according to an embodiment of the present application.

[0034] Figure 2 is a schematic diagram of a solid-state battery monomer according to an embodiment of the present application.

[0035] Figure 3 is Figure 2 the exploded view of the solid-state battery monomer according to an embodiment of the present application shown.

[0036] Figure 4 This is a schematic diagram of a battery device according to one embodiment of this application.

[0037] Figure 5 This is a schematic diagram of a battery pack according to one embodiment of this application.

[0038] Figure 6 for Figure 5 An exploded view of a battery pack according to one embodiment of this application is shown.

[0039] Figure 7 This is a schematic diagram of an electrical device that uses a solid-state battery as a power source according to one embodiment of this application.

[0040] Explanation of reference numerals in the attached figures:

[0041] 1. Battery pack; 2. Upper casing; 3. Lower casing; 4. Battery assembly; 5. Solid-state battery cell; 51. Housing; 52. Solid-state battery cell; 53. Cover plate; 6. Electrical device. Detailed Implementation

[0042] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0043] The "range" disclosed in this application can be defined in the form of 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; any endpoint can be independently included or excluded, and they can be combined arbitrarily, meaning 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 ​​1 and 2 are listed, and maximum range values ​​3, 4, and 5 are also 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 document; "0-5" is simply a shortened representation of these numerical combinations. Furthermore, stating that a parameter is an integer ≥2 is equivalent to disclosing that the parameter is, for example, an integer 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc. For instance, stating that a parameter is an integer selected from "2-10" is equivalent to listing the integers 2, 3, 4, 5, 6, 7, 8, 9, and 10.

[0044] In this application, the terms "multiple" or "various" are used unless otherwise specified, referring to a quantity greater than or equal to 2. For example, "one or more" means one or more types.

[0045] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions.

[0046] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment or implementation of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments. The term "implementation" as used herein has a similar understanding.

[0047] Those skilled in the art will understand that the order in which the steps are written in the methods of various embodiments or examples does not imply a strict execution order and does not constitute any limitation on the implementation process. The detailed execution order of each step should be determined by its function and possible internal logic. 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) can 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.

[0048] In this application, open-ended technical features or solutions described using terms such as "containing," "including," or "comprising" do not exclude additional members beyond those listed unless otherwise specified. They can be considered as providing both closed-ended features or solutions comprised of the listed members and open-ended features or solutions that include additional members beyond the listed members. For example, if A includes a1, a2, and a3, it may also include other members or exclude additional members unless otherwise specified. This can be considered as providing both the feature or solution that "A consists of a1, a2, and a3" and the feature or solution that "A includes not only a1, a2, and a3, but also other members."

[0049] In this application, unless otherwise specified, A (e.g., B) means that B is a non-limiting example of A, and it is understood that A is not limited to B.

[0050] In this application, "optionally," "optionally," and "optional" mean that something is optional, that is, it means that it is selected from either "with" or "without." If there are multiple "optional" entries in a technical solution, unless otherwise specified and there are no contradictions or mutual constraints, each "optional" entry shall be independent.

[0051] In traditional solid-state batteries, the chemical composition and properties of the solid electrolyte in the solid electrolyte layer and the positive electrode active material in the positive electrode active material layer are usually quite different. This results in poor interfacial compatibility between the solid electrolyte layer and the positive electrode layer, leading to less than ideal battery performance, such as cycle performance. Moreover, when the positive electrode active material is a high-voltage material, the ion transport impedance problem caused by poor interfacial compatibility between the positive electrode layer and the solid electrolyte layer is amplified due to the battery cycling at high voltage. Therefore, the problem of poor battery cycle performance is particularly prominent when the positive electrode active material is a high-voltage material.

[0052] In view of this, this application provides a solid-state battery, a halide solid electrolyte, and an electrical device. In this solid-state battery, by incorporating the halide solid electrolyte provided in this application into the positive electrode active material layer, the interfacial compatibility between the solid electrolyte layer and the positive electrode layer can be improved, thereby improving the cycle performance of the battery when the positive electrode active material is a high-voltage material. The solid-state battery, halide solid electrolyte, and electrical device will be described in detail below.

[0053] Unless otherwise specified, the term "solid-state battery" in this application refers to a battery in which the electrolyte includes a solid electrolyte. Typically, a solid-state battery includes a positive electrode, a solid electrolyte layer, and a negative electrode. During charging and discharging, active ions repeatedly insert and extract between the positive and negative electrodes. The solid electrolyte layer acts as a conductor of ions between the positive and negative electrodes and also isolates them, preventing short circuits. Therefore, a separator, as found in traditional lithium-ion batteries, is not required in solid-state batteries. Solid-state batteries use a non-flammable solid electrolyte instead of the organic electrolyte in traditional liquid lithium-ion batteries, significantly improving battery safety. In addition to enhanced safety, solid-state batteries are better suited for high-energy-density positive and negative electrode materials and reduce system weight, thus facilitating improvements in energy density.

[0054] In this application, unless otherwise specified, "solid electrolyte" refers to an electrolyte material or substance that exists in solid form during the storage and fabrication of solid-state batteries and their components, as well as during the operation of solid-state batteries. This includes, but is not limited to, solid electrolytes existing in solid form at room temperature.

[0055] In this application, unless otherwise specified, "negative electrode active material" refers to a substance used in the positive electrode sheet that is capable of reversibly inserting and extracting active ions; "positive electrode active material" refers to a substance used in the positive electrode sheet that is capable of reversibly extracting and inserting active ions. During solid-state battery charging, active ions are extracted from the positive electrode, pass through the solid electrolyte layer, and insert into the negative electrode; conversely, during solid-state battery discharging, active ions are extracted from the negative electrode and insert into the positive electrode. The active ions are not specifically limited or restrictive; they can be lithium ions, in which case it corresponds to a lithium-ion solid-state battery. It can be understood that the positive electrode active material layer contains positive electrode active material, and the negative electrode active material layer contains negative electrode active material.

[0056] In a first aspect, this application provides a solid-state battery, which includes a positive electrode sheet, the positive electrode sheet including a positive active material layer, the positive active material layer comprising a positive active material and a halide solid electrolyte; the positive active material includes a high-voltage material, the highest charging cut-off voltage of the high-voltage material being greater than or equal to 4.3V;

[0057] The halide solid electrolyte includes one or more of the compounds satisfying the chemical formula Li 3-2a-b A a B b C c D d E e O n Cl 6-m-2n F m wherein, A includes one or more of Ta, Nb and V, B includes one or two of Zr and Hf, C, D, and E each independently include a trivalent metal element, 0 < a ≤ 0.6, 0 < b ≤ 0.6, 0 < c < 0.3, 0 < d < 0.3, 0 < e < 0.3, c = d = e, 0 ≤ n ≤ 0.5, and the value of m makes the algebraic sum of the valences of the compound zero.

[0058] In the above solid-state battery provided by the present application, a halide solid electrolyte satisfying the above chemical formula is added to the positive electrode active material layer, that is, a high-voltage material and the halide solid electrolyte are used in combination in the positive electrode active material layer. Due to the halide solid electrolyte satisfying this chemical formula, there are较多 lattice distortions and a较高 degree of structural disorder inside it. Therefore, when cycling at a high voltage, it can effectively promote the activation of lithium ions, reduce the ion transport impedance between the positive electrode layer and the solid electrolyte layer, improve the ion transport rate, effectively improve the interfacial compatibility between the solid electrolyte layer and the positive electrode layer, and improve the cycle performance and rate performance of the battery. Compared with the method of using a traditional halide solid electrolyte or a halogen oxide solid electrolyte as a positive electrode additive and combining it with the positive electrode active material, the halide solid electrolyte provided by the present application is a high-entropy system, so its stability at a high oxidation potential is better. Therefore, when it is combined with a high-voltage material, it can effectively improve the cycle performance of the battery.

[0059] It should be noted that the "positive electrode layer" described in the present application at least includes a positive electrode active material layer.

[0060] It should be noted that the "traditional halide solid electrolyte" described in the present application refers to a solid electrolyte satisfying the chemical formula Li3M1X16, where M1 includes one or more of trivalent rare earth elements, and X1 includes one or more of halogens; this traditional halide solid electrolyte can be, for example, Li3InCl6, Li3YCl6 or Li3HoCl6;

[0061] The "halogen oxide solid electrolyte" refers to a solid electrolyte satisfying the chemical formula Li3M2OX14, where M2 includes one or more of trivalent metal elements, and X2 includes one or more of halogens; this halogen oxide solid electrolyte can be, for example, LiTaOCl4 or LiNbOCl4.

[0062] As an example, the following method can be used to obtain a sample of the positive electrode active material layer in a solid-state battery: After disassembling the battery, remove the positive electrode sheet and soak it in dimethyl carbonate for a certain period of time (e.g., 2h~10h); then remove the positive electrode sheet and dry it at a certain temperature and time (e.g., 60℃, more than 4h), and remove the dried positive electrode sheet. Bake the dried positive electrode sheet at a certain temperature and time (e.g., 400℃, more than 2h), and randomly select a region of the baked positive electrode sheet to sample the positive electrode active material layer (a blade can be used to scrape off the powder for sampling). Soak the collected sample in N-methylpyrrolidone for a certain period of time, filter it, and wash the solid material; dissolve the washed solid material in a mixed solution of acetonitrile and water, soak it for a period of time, filter it, and dry the obtained solid material to obtain the positive electrode active material sample; at the same time, dry and crystallize the filtrate to obtain the halide solid electrolyte sample.

[0063] As an example, the positive electrode active material sample obtained in the aforementioned steps can be prepared into a mold battery or a stacked battery. By performing a charging test on the mold battery or stacked battery, its maximum charging cut-off voltage can be measured. For instance, in a battery testing system, the mold battery or stacked battery is charged with a constant current while the battery voltage change is monitored in real time. As the charging process proceeds, the battery voltage gradually increases. When the battery voltage reaches a specific value, the rate of voltage increase will suddenly accelerate, or a voltage plateau will appear. This specific voltage value can be identified as the maximum charging cut-off voltage.

[0064] As an example, the chemical composition of the halide solid electrolyte sample obtained in the aforementioned steps can be determined by inductively coupled plasma mass spectrometry.

[0065] In some embodiments, a can be 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, or a range of any of the above values.

[0066] In some embodiments, b can be 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, or a range of any of the above values.

[0067] In some embodiments, c, d, and e may each be independently 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, or within any range of the above values.

[0068] In some embodiments, n can be 0, 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5 or within the range composed of any of the above values.

[0069] In some embodiments, the highest charging cut-off voltage of the high-voltage material is 4.3V - 4.8V. For example, the highest charging cut-off voltage can be 4.3V, 4.4V, 4.5V, 4.6V, 4.7V, 4.8V or within the range composed of any of the above values. Thus, when the high-voltage material is paired with the aforementioned halide solid electrolyte, the cycling performance of the battery can be effectively improved.

[0070] The high-voltage material includes one or more of lithium nickel cobalt manganese oxide and lithium-rich manganese-based oxide, and the lithium nickel cobalt manganese oxide satisfies the chemical formula LiNi x Co y Mn 1-x-y O2, 0.8 < x < 1, 0 < y < 0.1; the lithium-rich manganese-based oxide satisfies the chemical formula x’Li2MnO3·(1 - x’)LiMO2, M includes transition metal elements, 0 < x’ < 1.

[0071] When the lithium nickel cobalt manganese oxide and / or lithium-rich manganese-based oxide that satisfy the above chemical formula are used as the high-voltage material and paired with the aforementioned halide solid electrolyte, the promoting effect of the halide solid electrolyte on ion activation during cycling at high voltage can be better exerted, the interfacial compatibility between the solid electrolyte layer and the positive electrode layer can be further improved, and thus the cycling performance of the battery can be further improved.

[0072] It can be understood that the "lithium-rich manganese-based oxide" described in this application refers to a material with a composite structure composed of layered Li2MnO3 and LiMO2.

[0073] As an example, the composition of the positive electrode active material can be tested by the following method: performing inductively coupled plasma mass spectrometry on the positive electrode active material sample obtained in the aforementioned step, and the composition of the positive electrode active material sample can be determined.

[0074] In some embodiments, the transition metal elements include, but are not limited to, one or more of Ni, Co, Fe, Sc, Ti, V, Cr, Fe, Cu, Zn, and Mn.

[0075] In some embodiments, x can be 0.83, 0.85, 0.87, 0.89, 0.9, 0.93, 0.95, 0.97, 0.99 or within the range composed of any of the above values.

[0076] In some embodiments, y can be 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, or within any of the above values.

[0077] In some embodiments, x' can be 0.05, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 0.99, or a range of any of the above values.

[0078] In some implementations, 0.83 ≤ x ≤ 0.98. When the nickel content in lithium nickel cobalt manganese oxide is within this range, its maximum charging cut-off voltage will be relatively higher. For high-voltage materials within this range, pairing them with halide solid electrolytes will improve the interfacial compatibility between the solid electrolyte layer and the positive electrode layer, thus resulting in better battery cycle performance.

[0079] In some implementations, 0.35 ≤ x' ≤ 0.75. When the content of Li2MnO3 in the lithium-rich manganese-based oxide is within this range, for high-voltage materials within this range, the combination of halide solid electrolyte with it has a better effect on improving the interfacial compatibility between the solid electrolyte layer and the positive electrode layer, thus resulting in better battery cycle performance.

[0080] In some implementations, C, D, and E each independently include one or more of Sc, Y, La, Ce, Nd, Pm, Sm, Ho, Er, Yb, Al, and In.

[0081] In some embodiments, the lithium nickel cobalt manganese oxide includes LiNi 0.83 Co 0.07 Mn 0.08 O2, LiNi 0.90 Co 0.05 Mn 0.05 O2, LiNi 0.94 Co 0.03 Mn 0.03 O2 and LiNi 0.96 Co 0.02 Mn 0.02 One or more of O2. When these lithium nickel cobalt manganese oxides are combined with the aforementioned halide solid electrolytes, they improve the interfacial compatibility between the solid electrolyte layer and the positive electrode layer, enabling the battery to have higher cycle performance.

[0082] In some embodiments, the lithium-rich manganese-based oxide includes one or more of 0.45Li2MnO3·0.55LiNiO2, 0.55Li2MnO3·0.45LiNiO2, 0.55Li2MnO3·0.45LiCoO2, and 0.35Li2MnO3·0.75LiMnO2. After these lithium-rich manganese-based oxides are combined with the aforementioned halide solid electrolyte, the improvement effect on the interfacial compatibility between the solid electrolyte layer and the cathode layer is better, enabling the battery to have higher cycling performance.

[0083] In some embodiments, 0 < n ≤ 0.5. The anion side of the halide solid electrolyte contains oxygen element, which can effectively improve the water stability of the halide solid electrolyte; meanwhile, due to the relatively high electronegativity of oxygen element, the stability of the halide solid electrolyte at high oxidation potential can be further improved, thus facilitating the improvement of the cycling performance of the battery.

[0084] In some embodiments, 0.1 ≤ n ≤ 0.5. Thus, it is beneficial to further improve the stability of the halide solid electrolyte at high oxidation potential, thereby improving the cycling performance of the battery.

[0085] In some embodiments, the halide solid electrolyte includes one or more of the compounds satisfying the chemical formula Li 3-2a- b A a Zr b In c D d E e O n Cl 6-m-2n F m where A is one or both of Ta and Nb, D and E are each independently one or more of Y, Er, Yb, and Ho, 0.3 ≤ a ≤ 0.6, 0.2 ≤ b ≤ 0.6, 0 < c < 0.3, 0 < d < 0.3, 0 < e < 0.3, c = d = e, 0.25 ≤ n ≤ 0.5, and the value of m makes the algebraic sum of the valences of the compound zero.

[0086] Thus, there are more lattice distortions and higher structural disorder in the halide solid electrolyte, and its stability at high oxidation potential is better. Therefore, when it is combined with high-voltage materials and cycled at high voltage, it can more effectively promote the activation of lithium ions, further improve the ion transport rate, and further effectively improve the interfacial compatibility between the solid electrolyte layer and the cathode layer, thereby further improving the cycling performance of the battery.

[0087] In some embodiments, the average particle size of the halide solid electrolyte is 0.3 μm to 10 μm. For example, the average particle size can be 0.3 μm, 0.5 μm, 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, or within any range of the above values. This facilitates interfacial contact between the halide solid electrolyte and the solid electrolyte layer, improving interfacial ion transport kinetics.

[0088] In some embodiments, the average particle size of the halide solid electrolyte is 0.3 μm to 2 μm. For example, the average particle size can be 0.3 μm, 0.5 μm, 0.7 μm, 0.9 μm, 1 μm, 1.1 μm, 1.3 μm, 1.5 μm, 1.7 μm, 1.9 μm, 2 μm, or within any range of the above values. This is beneficial for further improving the interfacial ion transport kinetics.

[0089] It should be noted that the "average particle size of halide solid electrolytes" mentioned in this application refers to the Dv99 particle size of the halide solid electrolyte, that is, the particle size corresponding to a cumulative volume distribution of 99% in the halide solid electrolyte particle system. As an example, the average particle size of halide solid electrolytes can be determined using a laser particle size analyzer (such as Malvern MasterSize 3000).

[0090] In some embodiments, the mass ratio of the positive electrode active material to the halide solid electrolyte is (60~80):(37~17). For example, this mass ratio can be 60:37, 60:30, 60:25, 60:20, 60:17, 80:37, 80:30, 80:25, 80:20, 80:17, or within any range of the above values. This allows for a more effective combination of the positive electrode active material and the halide solid electrolyte, resulting in further improved cycle performance of the battery.

[0091] In some embodiments, the positive electrode active material layer further comprises a conductive agent, and the mass ratio of the conductive agent to the positive electrode active material is 3:(60~80). For example, this mass ratio can be 3:80, 3:75, 3:70, 3:65, 3:60, or within any range of the above values. This enables the positive electrode to possess good electron transport properties.

[0092] In some embodiments, the conductive agent includes, but is not limited to, one or more of carbon nanotubes (CNTs), graphite, acetylene black, and vapor-grown carbon fibers (VGCF).

[0093] In some embodiments, the solid-state battery further includes a solid electrolyte layer comprising a sulfide solid electrolyte. This improves the compatibility between the positive electrode layer and the solid electrolyte layer, enhances the interfacial compatibility between the positive electrode layer and the solid electrolyte layer due to the halide solid electrolyte, and results in better battery cycle performance.

[0094] In some embodiments, the sulfide solid electrolyte includes Li6PS5Cl (LPSC), Li 10 GeP2S 12 (LGPS) and Li7P3S 11 One or more of them.

[0095] In some embodiments, the solid-state battery is an all-solid-state battery.

[0096] In this application, unless otherwise specified, "all-solid-state battery" refers to a solid-state battery in which all electrolytes are solid electrolytes. In this case, the positive electrode, the positive electrode plate and the electrolyte are all made of solid materials, and no liquid electrolyte is provided in the battery, so it can be called an "all-solid-state battery".

[0097] A solid-state battery includes at least one solid-state battery cell. A solid-state battery may include one or more solid-state battery cells.

[0098] In this application, unless otherwise specified, "solid-state battery cell" refers to a basic unit capable of converting chemical energy into electrical energy, and all its components are solid-state. In some embodiments, a solid-state battery cell may be an all-solid-state battery cell.

[0099] In this application, unless otherwise specified, "all-solid-state battery cell" refers to a solid-state battery cell in which all electrolytes are solid electrolytes. In this case, the positive electrode, positive electrode plate and electrolyte are all made of solid materials, and no liquid electrolyte is provided in the battery cell, so it can be called "all-solid-state battery cell".

[0100] Non-limitingly, a solid-state battery cell (which can be an all-solid-state battery cell) may include a positive electrode, a solid electrolyte layer, and a negative electrode, with the solid electrolyte layer located between the positive and negative electrodes. During battery charging and discharging, active ions repeatedly insert and extract between the positive and negative electrodes. The solid electrolyte layer serves to conduct ions between the positive and negative electrodes and also isolates them, thus preventing short circuits between the positive and negative electrodes.

[0101] In some embodiments, the solid-state battery cell 5 includes a solid-state cell 52.

[0102] In some implementations, the solid-state cell is an all-solid-state cell.

[0103] In some embodiments, the solid-state cell 52 (which may be an all-solid-state cell) includes a positive electrode, a solid electrolyte layer, and a negative electrode stacked sequentially.

[0104] Positive electrode sheet

[0105] In some embodiments, the positive electrode includes a positive current collector and a positive active material layer disposed on at least one surface of the positive current collector, the positive active material layer comprising a positive active material and a halide solid electrolyte.

[0106] As a non-limiting example, the positive current collector has two surfaces opposite each other in its own thickness direction, and the positive active material layer is disposed on either or both of the two opposite surfaces of the positive current collector.

[0107] In some embodiments, the positive electrode current collector may 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 obtained by forming a metal material on a polymer material substrate. Non-limiting examples of the metal material in the positive electrode current collector may include one or more of aluminum, aluminum alloys, nickel, nickel alloys, titanium, titanium alloys, silver, and silver alloys. Non-limiting examples of the polymer material substrate in the positive electrode current collector may include one or more of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), and polyethylene (PE).

[0108] In some embodiments, the positive electrode active material, in addition to lithium nickel cobalt manganese oxide and / or lithium-rich manganese-based oxide, may optionally include one or more of the following materials: lithium cobalt oxide (such as LiCoO2), lithium nickel oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt aluminum oxide, and their modified compounds. Non-limiting examples of lithium cobalt oxide may include LiCoO2; non-limiting examples of lithium nickel oxide may include LiNiO2; non-limiting examples of lithium nickel cobalt aluminum oxide may include LiNi 0.8 Co 0.15 Al 0.05 O2.

[0109] Understandably, lithium (Li) is intercalated and deintercalated during the charging and discharging process of a battery, and the Li content in the positive electrode varies depending on the state of discharge. Unless otherwise specified, the Li content in the examples of positive electrode materials listed in this application refers to the initial state of the material. When a positive electrode material is applied to a positive electrode in a battery system, the Li content in the positive electrode material typically changes after charge-discharge cycles. The Li content can be measured using molar content, but is not limited to this. Regarding "Li content refers to the initial state of the material," the initial state of the material refers to its state before being added to the positive electrode slurry. It is understood that new materials obtained by appropriately modifying the listed positive electrode materials are also within the scope of positive electrode materials. The aforementioned appropriate modification refers to acceptable modification methods for the positive electrode material; non-limiting examples include coating modification.

[0110] In the examples of cathode materials in this application, the oxygen (O) content is only a theoretical value. Lattice oxygen release will cause changes in the molar content of oxygen, and the actual O content will fluctuate. The O content can be measured in molar content, but is not limited to this.

[0111] In some embodiments, the positive electrode active material layer may optionally include a binder (which may be referred to as a positive electrode binder). As a non-limiting example, the positive electrode 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.

[0112] In some embodiments, the positive electrode sheet can be prepared by dry or wet methods. For example, it can be dry-pressed into a film. Alternatively, it can be wet-coated and dried to form a film.

[0113] As a non-limiting example, the positive electrode sheet can be prepared by: dry mixing the components used to prepare the positive electrode sheet, such as the positive electrode active material, halide solid electrolyte, conductive agent, positive electrode binder, and any other components; then heating and pressurizing the mixed material to knead it into a clump; hot rolling pressing to form a self-supporting positive electrode sheet; and hot rolling bonding the self-supporting positive electrode sheet with a positive electrode current collector, wherein the self-supporting positive electrode sheet can be bonded to at least one side (single or double sides) of the positive electrode current collector to obtain the positive electrode sheet. Non-limitingly, a dual planetary mixer can be used for dry mixing. Non-limitingly, a kneading and pressing process can be performed using a Banbury mixer. Non-limitingly, the temperature for hot rolling pressing can be 75°C to 85°C, and further, such as 78°C, 80°C, 82°C, etc. The method for assembling solid-state batteries using the positive electrode sheet is suitable for industrial mass production.

[0114] Negative electrode sheet

[0115] In some embodiments, the negative electrode sheet includes a negative electrode active material layer, which includes a negative electrode active material.

[0116] In some implementations, the negative electrode active material is a lithium indium alloy (InLi alloy).

[0117] In some implementations, the negative electrode is an InLi alloy film.

[0118] In some embodiments, the negative electrode active material may also be a negative electrode active material known in the art for use in solid-state batteries. As a non-limiting example, the negative electrode active material may include one or more of the following materials: elemental silicon, elemental tin, silicon-carbon composites, silicon suboxide, graphite, and metallic lithium. However, this application is not limited to these materials or substances, and other conventional materials that can be used as battery negative electrode active materials may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0119] In some embodiments, the negative electrode sheet may include a negative current collector and a negative active material layer disposed on at least one surface of the negative current collector, the negative active material layer comprising a negative active material. As a non-limiting example, the negative current collector has two surfaces opposite to each other in its own thickness direction, and the negative active material layer is disposed on either or both of the two opposite surfaces of the negative current collector.

[0120] In some embodiments, the negative electrode current collector may be a metal foil or a composite current collector. For example, copper foil may be used as the metal foil. In the negative electrode current collector, 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. In the negative electrode current collector, the composite current collector may be formed by forming a metal material on the polymer material substrate. Non-limiting examples of the metal material in the negative electrode current collector may include one or more of copper, copper alloys, nickel, nickel alloys, titanium, titanium alloys, silver, and silver alloys. Non-limiting examples of the polymer material substrate in the negative electrode current collector may include one or more of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), and polyethylene (PE).

[0121] In some embodiments, the negative electrode active material layer may optionally include a conductive agent (which may be referred to as a negative electrode conductive agent). Without limitation, the negative electrode conductive agent may include one or more of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.

[0122] In some embodiments, the negative electrode active material layer may optionally include an adhesive (denoted as negative electrode adhesive). As a non-limiting example, the negative electrode adhesive may include one or more of styrene-butadiene rubber (SBR), polyacrylic acid (PAA), sodium polyacrylate (PAAS), polyacrylamide (PAM), polyvinyl alcohol (PVA), sodium alginate (SA), polymethacrylic acid (PMAA), and carboxymethyl chitosan (CMCS).

[0123] In some embodiments, the negative electrode active material layer may optionally include other additives, such as thickeners (e.g., sodium carboxymethyl cellulose (CMC-Na)).

[0124] In some embodiments, the negative electrode sheet can be prepared by dry or wet methods. For example, it can be dry-pressed into a film. Alternatively, it can be wet-coated into a film.

[0125] As a non-limiting example, the negative electrode sheet can be prepared by dispersing the components used to prepare the negative electrode sheet, such as the negative electrode active material, negative electrode conductive agent, negative electrode binder, and any other components, in a solvent (a non-limiting example of a solvent is p-xylene) to form a negative electrode slurry. Further, the negative electrode slurry is coated onto at least one surface of the negative electrode current collector, and after drying, cold pressing, and other processes, the negative electrode sheet is obtained. Cold pressing can be performed using a cold rolling mill. The surface of the negative electrode current collector coated with the negative electrode slurry can be a single surface of the negative electrode current collector or both surfaces of the negative electrode current collector. The solid content of the negative electrode slurry can be 30wt% to 70wt%, optionally 40wt% to 60wt%. The viscosity of the negative electrode slurry at room temperature can be adjusted to 2000 mPa·s to 10000 mPa·s, optionally 3000 mPa·s to 10000 mPa·s. When coating the negative electrode slurry, the coating density per unit area (after deducting solvent) on a dry weight basis, based on the amount coated on one side of the negative electrode current collector, can be 1.5 mg / cm². 2 ~ 22 mg / cm 2 However, this is not the only possibility. The compaction density of the negative electrode sheet can be 1.0 g / cm³. 3 ~ 2.0 g / cm 3 1.0 g / cm³ is an optional value. 3 ~ 1.8 g / cm 3 .

[0126] solid electrolyte layer

[0127] The solid electrolyte layer acts as a conductor of ions between the positive and negative electrodes, and can also isolate the positive and negative electrodes to prevent short circuits between them.

[0128] It is understood that the solid electrolyte layer includes a solid electrolyte. In addition to sulfide solid electrolytes, the solid electrolyte in the solid electrolyte layer may optionally include other solid electrolytes known in the art that can be used in solid-state batteries, such as one or more of halide solid electrolytes, oxide solid electrolytes, and polymer solid electrolytes.

[0129] In some embodiments, non-limiting examples of sulfide solid electrolytes may include Li 10 GeP2S 12 Li₂S-P₂S₅, Argyrodite type (such as Li₆PS₅Cl, Li 5.5 PS 5.5 Cl 1.5 One or more of the following: etc.

[0130] In some embodiments, non-limiting examples of oxide-based solid electrolytes may include LISICON-type oxide electrolytes (such as γ-Li3PO4, etc.), NASICON-type oxide electrolytes (such as Li... 1+x Al x Ge 2-x (PO4)3, Li 1+ x Al x Ti 2-x (PO4)3, etc., 0≤x≤1), Garnet-type oxide electrolytes (such as Li7La3Zr2O12, etc.), Perovskite-type oxide electrolytes (such as Li 3x La 2 / 3-x One or more of the following: TiO3, etc. (0≤x≤0.5).

[0131] In some embodiments, non-limiting examples of halide-based solid electrolytes may include one or more of Li3InCl6, Li3YCl6, Li3ScCl6, Li3ErCl6, Li2ZrCl6, etc.

[0132] The solid electrolyte layer can be prepared using a dry method. In some embodiments, the solid electrolyte layer can be formed by pressing a solid electrolyte material into a solid electrolyte membrane. In other embodiments, the solid electrolyte layer is formed by pressing the constituent raw materials of the solid electrolyte layer onto an electrode layer. In still other embodiments, the solid electrolyte membrane can also be prepared using methods such as fibrosis combined with calendering, melt extrusion, or spraying.

[0133] Solid electrolyte layers can also be prepared using a wet process. The electrolyte slurry used includes at least a solid electrolyte and an organic solvent, and usually also includes one or more of a binder and a dispersant.

[0134] It is understood that the "electrode layer" mentioned in this application refers to the positive electrode or the negative electrode.

[0135] In some embodiments, the thickness of the solid electrolyte layer can be 0.1 μm to 1000 μm, and can be selected as 10 μm to 100 μm, 100 μm to 800 μm, 500 μm to 800 μm, etc.

[0136] In a non-limiting manner, the positive electrode, the solid electrolyte layer, and the negative electrode can be assembled in a stacked manner, with the solid electrolyte layer placed between the positive electrode and the negative electrode.

[0137] Non-limitingly, a solid-state battery cell can be prepared by stacking a positive electrode, a solid electrolyte membrane, and a negative electrode in sequence, placing the solid electrolyte membrane between the positive and negative electrodes, and then rolling them together.

[0138] Non-limitingly, a solid-state battery cell can be prepared by stacking a positive electrode membrane, a solid electrolyte membrane, and a negative electrode membrane in sequence, placing the solid electrolyte membrane between the positive electrode membrane and the negative electrode membrane, and then rolling it.

[0139] The rolling process can be either cold rolling or hot rolling. A non-limiting example of a temperature for hot rolling is 180°C.

[0140] In some embodiments, the solid-state battery may include an outer packaging. This outer packaging can be used to encapsulate the aforementioned solid-state battery cell.

[0141] In some embodiments, the outer packaging of a solid-state battery can be a rigid shell, such as a hard plastic shell, an aluminum shell, or a steel shell. The outer packaging of a solid-state battery can also be a soft pack, such as a pouch-type soft pack. The material of the soft pack can be plastic; further, non-limiting examples of plastics may include one or more of polypropylene, polybutylene terephthalate, and polybutylene succinate.

[0142] This application does not impose any particular limitation on the shape of the solid-state battery cell; it can be cylindrical, square, or any other arbitrary shape. For example, Figure 2 This is an example of a square-structured solid-state battery cell 5.

[0143] In some of these implementations, reference is made to... Figure 3 The outer packaging may include a housing 51 and a cover 53. The housing 51 may include a base plate and side plates connected to the base plate, the base plate and side plates forming a receiving cavity. The housing 51 has an opening communicating with the receiving cavity, and the cover 53 can be placed over the opening to close the receiving cavity. A solid-state battery cell 52 is encapsulated within the receiving cavity. The number of solid-state battery cells 52 contained in a single solid-state battery cell 5 may be one or more, which can be selected by those skilled in the art according to actual needs.

[0144] Solid-state batteries can be battery device 4 or battery pack 1.

[0145] The battery device includes at least one solid-state battery cell. The number of solid-state battery cells in the battery device can be one or more, and those skilled in the art can select an appropriate number according to the application and capacity of the battery device.

[0146] Figure 4 This is battery device 4, used as an example. (See reference...) Figure 4 In the battery device 4, multiple solid-state battery cells 5 can be arranged sequentially along the length of the battery device 4. Of course, they can also be arranged in any other manner. Furthermore, the multiple solid-state battery cells 5 can be fixed in place using fasteners.

[0147] Optionally, the battery device 4 may also include a housing with a receiving space in which a plurality of solid-state battery cells 5 are housed.

[0148] In some embodiments, the battery devices described above can also be assembled into a battery pack, and the number of battery devices contained in the battery pack can be one or more. Those skilled in the art can select an appropriate number according to the application and capacity of the battery pack.

[0149] Figure 5 and Figure 6 This is battery pack 1 as an example. (See reference...) Figure 5 and Figure 6 The battery pack 1 may include a battery box and multiple battery devices 4 disposed within the battery box. The battery box includes an upper body 2 and a lower body 3, with the upper body 2 covering the lower body 3 to form a closed space for accommodating the battery devices 4. The multiple battery devices 4 can be arranged in any manner within the battery box.

[0150] Secondly, this application provides a halide solid electrolyte, said halide solid electrolyte comprising the chemical formula Li 3-2a-b A a B b C c D d E e O n Cl 6-m-2n F m One or more of the compounds;

[0151] Among them, A includes one or more of Ta, Nb, and V, B includes one or both of Zr and Hf, C, D, and E are each independently a trivalent metal element, 0 < a ≤ 0.6, 0 < b ≤ 0.6, 0 < c < 0.3, 0 < d < 0.3, 0 < e < 0.3, c = d = e, 0 ≤ n ≤ 0.5, and the value of m makes the algebraic sum of the valences of the compound zero.

[0152] In some embodiments, the halide solid electrolyte is the halide solid electrolyte in the solid-state battery described in the first aspect of the present application.

[0153] The halide solid electrolyte of the second aspect of the present application has a similar function to the halide solid electrolyte in the solid-state battery of the first aspect of the present application, and will not be elaborated here.

[0154] In a third aspect, the present application provides a method for preparing a halide solid electrolyte, which can be used to prepare the halide solid electrolyte of the second aspect of the present application, and may include the following steps S1 to S2:

[0155] S1: Mix the precursor lithium salt and metal halide according to the stoichiometric ratio of the target product and then perform ball milling.

[0156] S2: Anneal the mixture after ball milling to prepare the halide solid electrolyte.

[0157] In some embodiments, the precursor lithium salt includes one or more of LiCl, LiF, Li2O, and Li2CO3.

[0158] In some embodiments, the metal halide includes one or more of TaCl5, NbCl5, VCl5, ZrCl4, HfCl4, InCl3, YCl3, ScCl3, ErCl3, YbCl3, HoCl3, TaF5, and NbF5.

[0159] In some embodiments, the ball milling medium for the ball milling includes zirconia beads; optionally, the diameter of the zirconia beads can be 10 mm, 5 mm, or 3 mm.

[0160] In some embodiments, the mass ratio of the balls to the material for the ball milling is (40 - 50):1.

[0161] In some embodiments, the ball milling speed for the ball milling is 400 rpm to 600 rpm.

[0162] In some embodiments, the ball milling duration for the ball milling is 15 h to 200 h.

[0163] In some embodiments, the annealing temperature for the annealing is 100°C to 240°C.

[0164] In some embodiments, the annealing holding time for the annealing treatment is 3h to 6h.

[0165] In some embodiments, the annealing process is performed under an inert atmosphere; alternatively, the inert atmosphere may be an argon atmosphere.

[0166] Fourthly, this application provides an electrical device that includes the solid-state battery described in the first aspect of this application.

[0167] In some embodiments, the electrical device includes at least one of the solid-state batteries of any of the embodiments provided in this application.

[0168] In a non-limiting sense, solid-state batteries can be used as a power source for electrical devices or as an energy storage unit for electrical devices. Electrical devices can include, but are not limited to, mobile devices, electric vehicles, electric trains, ships and satellites, energy storage systems, etc. Mobile devices can be, for example, mobile phones, laptops, etc.; electric vehicles can be, for example, pure electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, electric bicycles, electric scooters, electric golf carts, electric trucks, electric motorcycles, power tools, etc., but are not limited to these. This electrical device can also be applied to military equipment, aerospace, and other fields, and can also be applied to energy storage power systems such as hydroelectric, thermal, wind, and solar power plants.

[0169] As an electrical device, solid-state batteries can be selected based on its usage requirements.

[0170] Figure 7 Here is an example of an electrical device 6. This electrical device is a pure electric vehicle, a hybrid electric vehicle, or a plug-in hybrid electric vehicle, etc. To meet the high power and high energy density requirements of this electrical device for solid-state batteries, a battery device or battery pack can be used.

[0171] Another example device could be a mobile phone, tablet, or laptop. These devices typically require a thin and light design and can use solid-state batteries as their power source.

[0172] Example

[0173] The following describes some embodiments of this application. The embodiments described below are exemplary and are only used to explain this application, and should not be construed as limiting this application. Where the technology or conditions are not specified in the embodiments, they are performed according to the description above, or according to the technology or conditions described in the literature in this field, or according to the product instructions. Reagents or instruments whose manufacturers are not specified are all conventional products that can be obtained commercially, or can be synthesized from commercially available products using conventional methods.

[0174] In the following examples, room temperature refers to 20°C to 30°C.

[0175] Example 1

[0176] (1) Preparation of halide solid electrolytes

[0177] Precursor lithium salts LiCl, LiF, and Li₂O, and metal halides TaCl₅, ZrCl₄, InCl₃, YCl₃, and ErCl₃ were added to a ball mill jar in a specific stoichiometric ratio (LiCl:LiF:Li₂O:TaCl₅:ZrCl₄:InCl₃:YCl₃:ErCl₃ = 0.3:0.1:0.5:0.5:0.3:0.1:0.1:0.1). Zirconium beads with a diameter of 5 mm were used for ball milling. The ball-to-material mass ratio was controlled at 45:1, the milling speed at 500 rpm, and the milling time at 20 hours. After milling, the mixture was annealed in an inert argon atmosphere at 200℃ for 5 hours to obtain a solid product. This solid product was then ball-milled and sieved to obtain the halide solid electrolyte Li. 1.4 Ta 0.5 Zr 0.3 In 0.1 Y 0.1 Er 0.1 O 0.5 Cl 4.9 F 0.1 Its particle size ranges from 0.3μm to 5.2μm.

[0178] (2) Preparation of solid-state batteries

[0179] LiNi 0.83 Co 0.07 Mn 0.08 O2 (Ni83), halide solid electrolyte Li 1.4 Ta 0.5 Zr 0. 3In 0.1 Y 0.1 Er 0.1 O 0.5 Cl 4.9 F 0.1 A mixed positive electrode material was obtained by dry mixing the conductive agent with vapor-grown carbon fiber (70 mg, 27 mg, and 3 mg of the three components, respectively). 100 mg of a sulfide electrolyte, Li6PS5Cl, was placed in a mold and compacted under 125 MPa pressure to form a solid electrolyte layer (0.8 mm thick). 15 mg of the mixed positive electrode material and a Li-In alloy sheet were added to both sides of the solid electrolyte layer, and then the mixture was molded under 500 MPa pressure and held for 5 minutes to obtain a solid-state battery cell composed of a positive electrode, a solid electrolyte layer, and a negative electrode layer stacked sequentially. This solid-state battery cell was packaged in a hard plastic shell to obtain a solid-state battery.

[0180] Example 2

[0181] Similar to the preparation method in Example 1, the main difference is that in step (1), NbCl5 is used instead of TaCl5, and the amount of each metal halide is adjusted so that the final halide solid electrolyte is Li. 1.4 Nb 0.5 Zr 0.3 In 0.1 Y 0.1 Er 0.1 O 0.5 Cl 4.9 F 0.1 .

[0182] Example 3

[0183] Similar to the preparation method in Example 1, the main difference is that in step (1), the amounts of each precursor lithium salt and each metal halide are adjusted so that the final halide solid electrolyte is Li 1.4 Ta 0.6 Zr 0.2 In 0.1 Y 0.1 Er 0.1 O 0.25 Cl 5. 4F 0.1 .

[0184] Example 4

[0185] Similar to the preparation method in Example 1, the main difference is that in step (1), the amount of each metal halide is adjusted so that the final halide solid electrolyte is Li 1.4 Ta 0.3 Zr 0.6 In 0.1 Y 0.1 Er 0.1 O 0.5 Cl 4.9 F 0.1 .

[0186] Example 5

[0187] Similar to the preparation method in Example 1, the main difference is that in step (1), HoCl3 is used instead of ErCl3, and the amount of each metal halide is adjusted so that the final halide solid electrolyte is Li. 1.4 Ta 0.5 Zr 0.3 In 0.1 Y 0.1 Ho 0.1 O 0.5 Cl 4.9 F0.1 .

[0188] Example 6

[0189] Similar to the preparation method in Example 1, the main difference is that in step (1), NbCl5 is used instead of TaCl5, and the amounts of each precursor lithium salt and each metal halide are adjusted so that the final halide solid electrolyte is Li 1.4 Nb 0.6 Zr 0.2 In 0.1 Y 0.1 Er 0.1 O 0.25 Cl 5.4 F 0.1 .

[0190] Example 7

[0191] Similar to the preparation method in Example 1, the main difference is that in step (1), YbCl3 is used instead of YCl3, and the amount of each metal halide is adjusted so that the final halide solid electrolyte is Li. 1.4 Ta 0.5 Zr 0.3 In 0.1 Yb 0.1 Er 0.1 O 0.5 Cl 4.9 F 0.1 .

[0192] Example 8

[0193] Similar to the preparation method in Example 1, the main difference is that in step (1), YbCl3 is used instead of YCl3, and ScCl3 is used instead of ErCl3, and the amount of each metal halide is adjusted so that the final halide solid electrolyte is Li. 1.4 Ta 0. 5Zr 0.3 In 0.1 Yb 0.1 Sc 0.1 O 0.5 Cl 4.9 F 0.1 .

[0194] Example 9

[0195] Similar to the preparation method in Example 1, the main difference is that in step (1), the amount of each precursor lithium salt is adjusted so that the final halide solid electrolyte is Li 1.7 Ta 0.5 Zr 0.3 In 0.1 Y 0.1 Er0.1 O 0.1 Cl 5.7 F 0.1 .

[0196] Example 10

[0197] The preparation method is similar to that of Example 1, the main difference being that in step (2), equal masses of LiNi are used. 0.8 Co 0.1 Mn 0.1 O2 (NCM811) instead of LiNi 0.83 Co 0.07 Mn 0.08 O2 (Ni83).

[0198] Example 11

[0199] The preparation method is similar to that of Example 1, the main difference being that in step (2), equal masses of LiNi are used. 0.96 Co 0.02 Mn 0.02 O2 (Ni96) replaces LiNi 0.83 Co 0.07 Mn 0.08 O2 (Ni83).

[0200] Example 12

[0201] The preparation method is similar to that in Example 1, the main difference being that in step (2), 0.55Li2MnO3·0.45LiNiO2 of equal mass is used instead of LiNi. 0.83 Co 0.07 Mn 0.08 O2 (Ni83).

[0202] Comparative Example 1

[0203] The preparation method is similar to that of Example 1, the main difference being that in step (2), an equal mass of LiTa is used. 0.5 Zr 0.625 Cl 5.9 F 0.1 Replace Li 1.4 Ta 0.5 Zr 0.3 In 0.1 Y 0.1 Er 0.1 O 0.5 Cl 4.9 F 0.1 .

[0204] Comparative Example 2

[0205] The preparation method is similar to that in Example 1, the main difference being that in step (2), an equal mass of LiTaCl6 is used instead of Li. 1.4 Ta 0.5 Zr 0.3 In 0.1 Y 0.1 Er 0.1 O 0.5 Cl 4.9 F 0.1 .

[0206] Comparative Example 3

[0207] The preparation method is similar to that of Example 1, the main difference being that in step (2), LiTaOCl4 of equal mass is used instead of Li. 1.4 Ta 0.5 Zr 0.3 In 0.1 Y 0.1 Er 0.1 O 0.5 Cl 4.9 F 0.1 .

[0208] Comparative Example 4

[0209] The preparation method is similar to that of Example 1, the main difference being that in step (2), equal masses of LiNi are used. 0.5 Co 0.25 Mn 0.25 O2 (NCM211) replaces LiNi 0.83 Co 0.07 Mn 0.08 O2 (Ni83).

[0210] Some parameters of the above embodiments and comparative examples are shown in Table 1 below.

[0211] Table 1

[0212]

[0213] The performance of the halide solid electrolytes and solid-state batteries obtained in Examples 1-12 and Comparative Examples 1-4 was tested, and the test results are shown in Table 2 below.

[0214] Test section

[0215] (1) X-ray diffraction test

[0216] X-ray diffraction was used to test the halide solid electrolyte.

[0217] (2) Cyclic performance test

[0218] At 25°C, the solid-state battery was first charged to 4.8V at a current density of 0.1C (vs. Li). + / Li) (wherein, Example 10 is charged to 4.3V and Comparative Example 4 is charged to 4.2V), left to stand for 10 minutes, and then discharged to 2.6V at a current density of 0.1C (vs. Li) + / Li), cycle charge and discharge 3 times; then charge the solid-state battery to 4.8V at a current density of 0.33C (vs. Li). + / Li) (wherein, Example 10 is charged to 4.3V and Comparative Example 4 is charged to 4.2V), left to stand for 10 minutes, and then discharged to 2.8V at a current density of 0.33C (vs. Li) + The discharge specific capacity at this point is denoted as C1. The solid-state battery is cycled 50 times at a current density of 0.33C; the discharge capacity at this point is denoted as C2. The capacity retention rate of the solid-state battery after 50 cycles = C2 / C1 × 100%.

[0219] Table 2

[0220]

[0221] Table 2 shows that when Examples 1-12 are compared with Comparative Examples 1-3, the use of the halide solid electrolyte provided in this application as a positive electrode additive can enable the solid-state battery to have higher cycle performance. When Examples 1-12 are compared with Comparative Example 4, the halide solid electrolyte provided in this application has higher cycle performance when combined with high-voltage materials.

[0222] In addition, from Figure 1 It can be seen that the halide solid electrolyte prepared in this application has a crystalline structure.

[0223] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0224] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A solid-state battery, characterized in that, comprising a positive electrode plate, the positive electrode plate comprising a positive electrode active material layer, the positive electrode active material layer comprising a positive electrode active material and a halide solid electrolyte; the positive electrode active material comprises a high-voltage material, the highest charging cut-off voltage of the high-voltage material being greater than or equal to 4.3 V; The halide solid electrolyte includes one or more of the compounds satisfying the chemical formula Li 3-2a-b A a B b C c D d E e O n Cl 6-m-2n F m , where A includes one or more of Ta, Nb, and V, B includes one or both of Zr and Hf, C, D, and E each independently include a trivalent metal element, 0 < a ≤ 0.6, 0 < b ≤ 0.6, 0 < c < 0.3, 0 < d < 0.3, 0 < e < 0.3, c = d = e, 0 ≤ n ≤ 0.5, and the value of m makes the algebraic sum of the valences of the compound zero.

2. The solid-state battery according to claim 1, characterized in that, meeting one or more of the following conditions: (1) the highest charging cut-off voltage of the high-voltage material is 4.3 V to 4.8 V; (2) C, D, and E each independently comprise one or more of Sc, Y, La, Ce, Nd, Pm, Sm, Ho, Er, Yb, Al, and In.

3. The solid-state battery according to claim 1 or 2, characterized in that, 0<n≤0.5。 4. The solid-state battery according to any one of claims 1 to 3, characterized in that, 0.1≤n≤0.5。 5. The solid-state battery according to any one of claims 1 to 4, characterized in that, The halide solid electrolyte includes those satisfying the chemical formula Li 3-2a-b A a Zr b In c D d E e O n Cl 6-m-2n F m One or more of the compounds; wherein A is one or both of Ta and Nb, D and E each independently are one or more of Y, Er, Yb, and Ho, 0.3 ≤ a ≤ 0.6, 0.2 ≤ b ≤ 0.6, 0 < c < 0.3, 0 < d < 0.3, 0 < e < 0.3, c = d = e, 0.25 ≤ n ≤ 0.5, and m is valued such that the algebraic sum of the valences of the compound is zero.

6. The solid-state battery according to any one of claims 1 to 5, characterized in that, The positive electrode active material includes one or more of lithium nickel cobalt manganese oxide and lithium-rich manganese-based oxide, and the lithium nickel cobalt manganese oxide satisfies the chemical formula LiNi x Co y Mn 1-x-y O2, where 0.8 < x < 1 and 0 < y < 0.1; the lithium-rich manganese-based oxide satisfies the chemical formula x’Li2MnO3·(1-x’)LiMO2, M includes transition metal elements, and 0 < x’ < 1.

7. The solid-state battery according to claim 6, characterized in that, meeting one or more of the following conditions: （1）0.83≤x≤0.98； （2）0.35≤x’≤0.75。 8. The solid-state battery according to claim 6 or 7, characterized in that, The lithium nickel cobalt manganese oxide includes LiNi 0.83 Co 0.07 Mn 0.08 O2, LiNi 0.90 Co 0.05 Mn 0.05 O2, LiNi 0.94 Co 0.03 Mn 0.03 O2 and LiNi 0.96 Co 0.02 Mn 0.02 One or more of O2.

9. The solid-state battery according to any one of claims 6 to 8, characterized in that, the lithium-rich manganese-based oxide comprises one or more of 0.45Li2MnO3·0.55LiNiO2, 0.55Li2MnO3·0.45LiNiO2, 0.55Li2MnO3·0.45LiCoO2, and 0.35Li2MnO3·0.75LiMnO2.

10. The solid-state battery according to any one of claims 1 to 9, characterized in that, the average particle size of the halide solid electrolyte is 0.3 μm to 10 μm.

11. The solid-state battery according to any one of claims 1 to 10, characterized in that, the average particle size of the halide solid electrolyte is 0.3 μm to 2 μm.

12. The solid-state battery according to any one of claims 1 to 11, characterized in that, the mass ratio of the positive electrode active material to the halide solid electrolyte is (60 to 80):(37 to 17).

13. The solid-state battery according to any one of claims 1 to 12, characterized in that, the positive electrode active material layer further comprises a conductive agent, the mass ratio of the conductive agent to the positive electrode active material being 3:(60 to 80).

14. The solid-state battery according to any one of claims 1 to 13, characterized in that, the solid-state battery further comprises a solid electrolyte layer, the solid electrolyte layer comprising a sulfide solid electrolyte.

15. The solid-state battery according to any one of claims 1 to 14, characterized in that, the solid-state battery is a all-solid-state battery.

16. A halide solid electrolyte, characterized in that, The halide solid electrolyte includes those satisfying the chemical formula Li 3-2a-b A a B b C c D d E e O n Cl 6-m-2n F m One or more of the compounds; wherein A comprises one or more of Ta, Nb, and V, B comprises one or both of Zr and Hf, C, D, and E each independently are trivalent metal elements, 0 < a ≤ 0.6, 0 < b ≤ 0.6, 0 < c < 0.3, 0 < d < 0.3, 0 < e < 0.3, c = d = e, 0 ≤ n ≤ 0.5, and m is valued such that the algebraic sum of the valences of the compound is zero.

17. The halide solid electrolyte according to claim 16, characterized in that, the halide solid electrolyte is the halide solid electrolyte in the solid-state battery according to any one of claims 2 to 15.

18. An electrical appliance, characterized in that, comprising the solid-state battery according to any one of claims 1 to 15.

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