Solid-state battery, halide solid electrolyte of solid-state battery and preparation method of halide solid electrolyte

Abstract

The invention provides a solid-state battery, a halide solid electrolyte of the solid-state battery and a preparation method of the halide solid electrolyte. The solid-state battery comprises a positive pole piece, a halide solid electrolyte and a negative pole piece, the preparation method of the halide solid electrolyte comprises the following steps: grinding a first raw material required for preparing the halide solid electrolyte in a dry grinding manner, and sintering the ground material in an inert atmosphere to obtain a first reactant; the preparation method comprises the following steps: mixing a first reactant and a second raw material, grinding the mixed substance in a dry grinding manner, and sintering the ground substance in an inert atmosphere to obtain the halide solid electrolyte, wherein the first raw material comprises a compound containing Li, Zr and X elements; the second raw material comprises a compound containing an M element. The halide solid electrolyte has higher ionic conductivity, so that the electrochemical performance of the solid-state battery is improved.

Description

Technical Field

[0001] The present invention relates to the field of batteries, and in particular to a solid-state battery, a halide solid electrolyte of the solid-state battery, and a preparation method thereof. Background Art

[0002] The emerging halide solid electrolytes not only have extremely high theoretical lithium ion conductivity and a wide electrochemical window, but also have good machinability and electrode material compatibility. They show great practical potential in all-solid-state batteries and have become a hot topic of common concern in academia and industry.

[0003] Currently, when preparing halide solid electrolytes using a solid-phase method, all the raw materials required for preparation are ground and mixed before being sintered to obtain the halide solid electrolyte. However, due to the limitations of the grinding process, the raw materials cannot be fully mixed during the preparation process, which restricts the conductivity of the halide solid electrolyte and, in turn, limits the electrochemical performance of all-solid-state batteries. Summary of the Invention

[0004] The present invention provides a solid-state battery, a halide solid electrolyte for the solid-state battery, and a preparation method thereof, so as to improve the ionic conductivity of the halide solid electrolyte in the solid-state battery, thereby optimizing various chemical properties of the solid-state battery (such as interfacial impedance, cycle performance, and energy density, etc.).

[0005] A first aspect of the present invention provides a solid-state battery, comprising: a positive electrode sheet, a halide solid electrolyte, and a negative electrode sheet;

[0006] Wherein, the halide solid electrolyte is prepared by the following method:

[0007] Grinding a first raw material required for preparing the halide solid electrolyte by dry grinding to obtain a first precursor powder;

[0008] sintering the first precursor powder in an inert atmosphere to obtain a first reactant;

[0009] Mixing the first reactant with the second raw material, and grinding the mixture by dry grinding to obtain a second precursor powder;

[0010] sintering the second precursor powder in an inert atmosphere to obtain the halide solid electrolyte;

[0011] Among them, the first raw material includes a compound containing Li, Zr, and X elements, and X includes at least one of Cl, Br, or I elements; the second raw material includes a compound containing M elements, and M includes at least one of Y, In, Sc, or Yb elements.

[0012] According to an embodiment of the present invention, the chemical general formula of the halide solid electrolyte is ;

[0013] where 0 ≤ a ≤ 6, 0 < b ≤ 3, 0 < c ≤ 3, 0 < d ≤ 8, M includes at least one of Y, In, Sc, or Yb elements, and X includes at least one of Cl, Br, or I elements.

[0014] According to an embodiment of the present invention, 1 ≤ a ≤ 3.5; and / or, 0 ≤ b ≤ 1.5; and / or, 0 ≤ c ≤ 1.5; and / or, 3.5 ≤ d ≤ 7.5.

[0015] According to an embodiment of the present invention, M includes In and / or Y; X includes Cl and / or Br.

[0016] In the second aspect of the present invention, a preparation scheme for the halide solid electrolyte in a solid-state battery is provided, including

[0017] Grind the first raw material required for preparing the halide solid electrolyte by dry grinding to obtain a first precursor powder;

[0018] Sinter the first precursor powder in an inert atmosphere to obtain a first reactant;

[0019] Mix the first reactant with the second raw material, and grind the mixture by dry grinding to obtain a second precursor powder;

[0020] Sinter the second precursor powder in an inert atmosphere to obtain the halide solid electrolyte;

[0021] Among them, the first raw material includes a compound containing Li, Zr, and X elements, and X includes at least one of Cl, Br, or I elements; the second raw material includes a compound containing M elements, and M includes at least one of Y, In, Sc, or Yb elements.

[0022] According to an embodiment of the present invention, the sintering temperature is 100~400 °C.

[0023] According to an embodiment of the present invention, the sintering time is 1~40 h.

[0024] According to an embodiment of the present invention, the gas in the inert atmosphere includes at least one of argon, nitrogen or helium.

[0025] A third aspect of the present invention provides a halide solid electrolyte prepared by the method described in the second aspect above. The chemical general formula of the halide solid electrolyte is ;

[0026] where 0 ≤ a ≤ 6, 0 < b ≤ 3, 0 < c ≤ 3, 0 < d ≤ 8, M includes at least one of Y, In, Sc or Yb elements, and X includes at least one of Cl, Br or I elements.

[0027] According to an embodiment of the present invention, 1 ≤ a ≤ 3.5; and / or, 0 ≤ b ≤ 1.5; and / or, 0 ≤ c ≤ 1.5; and / or, 3.5 ≤ d ≤ 7.5.

[0028] According to an embodiment of the present invention, the M includes In and / or Y; the X includes Cl and / or Br.

[0029] A fourth aspect of the present invention provides an electrical device, including an electrical device main body and the solid-state battery of the first aspect.

[0030] In the implementation of the present invention, it has at least the following beneficial effects:

[0031] In the present invention, when preparing the halide solid electrolyte in the solid-state battery, by classifying the raw materials into two categories and grinding and calcining the raw materials in two times, more sufficient mixing between the raw materials is achieved, so as to obtain a halide electrolyte with higher ionic conductivity, and further achieve the effect of improving the overall electrochemical performance of the solid-state battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The drawings here are incorporated into the description and form a part of this description, showing embodiments consistent with the present application, and are used together with the description to explain the principles of the present application.

[0033] Figure 1 It is a schematic flow chart of a method for preparing a halide solid electrolyte provided in Embodiment 1 of the present invention.

[0034] Through the above drawings, the clear embodiments of the present application have been shown, and there will be more detailed descriptions later. These drawings and text descriptions are not intended to limit the scope of the concept of the present application in any way, but to explain the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0035] In order to enable those skilled in the art to better understand the scheme of the present invention, the present invention is further described in detail below. The specific embodiments listed below are only for describing the principles and features of the present invention. The examples are only used to explain the present invention and are not intended to limit the scope of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts are within the scope of protection of the present invention.

[0036] Based on the introduction of the above technical background, the inventors started from the physical properties of each raw material and took into account the differences in hardness, particle size, etc. of different types of raw materials. By grinding and sintering part of the raw materials to obtain a first reactant, and then grinding and sintering the remaining raw materials and the first reactant again to obtain a halide solid electrolyte, part of the raw materials can be fully refined, evenly contacted, and the initial reaction can be completed, thereby reducing the difficulty of mixing and reacting this part of the raw materials with the remaining raw materials, thereby greatly improving the mixing uniformity and reaction completion between the raw materials, and achieving the effect of improving the ionic conductivity of the halide solid electrolyte.

[0037] A first embodiment of the present invention provides a solid-state battery, comprising a positive electrode, a halide solid electrolyte, and a negative electrode.

[0038] Among them, halide solid electrolyte is used Figure 1 Prepared by the method shown, Figure 1 The flowchart of the method for preparing a halide solid electrolyte provided in the first embodiment of the present invention is as follows. Figure 1 As shown, the halide solid electrolyte is prepared by the following method:

[0039] S101. Grind a first raw material required for preparing a halide solid electrolyte by dry grinding to obtain a first precursor powder, wherein the first raw material includes a compound containing Li, Zr, and X elements, and X includes at least one of Cl, Br, or I elements.

[0040] Exemplarily, the dry grinding method may include a ball milling method or a grinding method using an agate mortar.

[0041] Specifically, the first raw material is part of the raw materials required to prepare the halide solid electrolyte, including a compound containing Li, Zr, and an element X, wherein X includes at least one of Cl, Br, or I. Exemplarily, the first raw material may include elements such as LiCl, LiBr, and ZrCl4.

[0042] S102. Sintering the first precursor powder in an inert atmosphere to obtain a first reactant.

[0043] The first reactant is a reactant obtained by sintering the raw materials in the first precursor powder.

[0044] S103. Mix the first reactant with the second raw material, and grind the mixture by dry grinding to obtain a second precursor powder, wherein the second raw material includes a compound containing the element M, and M includes at least one of the elements Y, In, Sc or Yb.

[0045] In this step, the dry grinding method is continued to be adopted to mix and grind the first reactant and the second raw material to obtain a second precursor powder.

[0046] Specifically, the second raw material is the remaining raw material required for preparing the halide solid electrolyte except for the first raw material, including a compound containing an M element, wherein M includes Y, In, Sc, or Yb. Exemplarily, the second raw material may include InCl3 and / or YCl3, etc.

[0047] S104. Sintering the second precursor powder in an inert atmosphere to obtain a halide solid electrolyte.

[0048] In this step, the precursor powder needs to be sintered to allow the second raw material and the first reactant to complete the remaining reaction, thereby obtaining a halide solid electrolyte.

[0049] It should be noted that, in the preparation process of the halide solid electrolyte, the present invention adopts the method of grinding and burning the raw materials twice, so that part of the raw materials are first fully refined, uniformly contacted and complete the initial reaction, thereby reducing the difficulty of mixing and reacting between this part of the raw materials and the remaining raw materials, greatly improving the mixing uniformity and reaction completion between the raw materials, and effectively improving the ionic conductivity of the halide solid electrolyte.

[0050] In addition, in the solid-state battery provided by the present invention, the positive electrode sheet specifically includes a positive electrode current collector and a positive electrode active layer formed of a positive electrode active material disposed on the surface of the positive electrode current collector. It should be understood that the present invention is not strictly limited to the positive electrode active material in the positive electrode sheet, and can be a positive electrode active material commonly used in lithium-ion batteries, such as at least one composite oxide of lithium and a metal selected from the group consisting of cobalt, manganese, nickel, and combinations thereof. Specifically, it can be at least one of lithium cobaltate, lithium nickelate, lithium manganate, nickel-cobalt-manganese ternary material, nickel-cobalt-aluminum ternary material, lithium iron phosphate (LFP), lithium nickel manganate, and lithium-rich manganese-based materials.

[0051] The negative electrode plate specifically includes a negative electrode current collector and a negative electrode active layer formed by a negative electrode active material disposed on the surface of the negative electrode current collector. It should be understood that the negative electrode active material in the negative electrode plate of the present invention is not strictly limited and may be a negative electrode active material commonly used in current lithium-ion batteries, such as at least one of graphite, hard carbon, soft carbon, mesophase carbon microspheres, silicon-based negative electrode materials (mainly including silicon monoxide, silicon-carbon negative electrodes), tin-based negative electrode materials (mainly including tin, tin alloys), etc.

[0052] As a specific example, in the preparation stage of the solid-state battery, after the halide solid electrolyte prepared by the above method is made into a powder form, it can be subjected to a pressing process using a powder press to obtain an electrolyte layer; after sequentially laminating and pressing the positive electrode plate, the electrolyte layer, and the negative electrode plate, a solid-state battery is formed by pressing.

[0053] In a possible implementation manner, the chemical general formula of the halide solid electrolyte in the solid-state battery can be , where 0 ≤ a ≤ 6, 0 < b ≤ 3, 0 < c ≤ 3, 0 < d ≤ 8, M includes at least one of the elements Y, In, Sc, or Yb, and X includes at least one of the elements Cl, Br, or I.

[0054] It should be understood that a, b, c, and d in the prepared halide solid electrolyte are determined according to the configuration ratios of the respective raw materials.

[0055] Exemplarily, the halide solid electrolyte can be Li 2.85 Y 0.85 Zr 0.15 Cl6, Li 2.9 In 0.9 Zr 0.1 Cl6, and Li 2.75 In 0.75 Zr 0.25 Cl6, etc.

[0056] As a preferred scheme, 1 ≤ a ≤ 3.5; and / or, 0 ≤ b ≤ 1.5; and / or, 0 ≤ c ≤ 1.5; and / or, 3.5 ≤ d ≤ 7.5.

[0057] It should be understood that when a in the chemical formula of the halide solid electrolyte is taken from any value in 1 to 3.5; and / or, b is taken from any value in 0 to 1.5; and / or, c is taken from any value in 0 to 1.5; and / or, d is taken from any value in 3.5 to 7.5, the performance of the halide dielectric is better and it has a higher ionic conductivity.

[0058] As a preferred scheme, M includes In and / or Y. It should be understood that when M in the chemical formula of the halide solid electrolyte is In, or Y, or In and Y, the performance of the halide solid electrolyte is better.

[0059] As a preferred solution, X includes Cl and / or Br. It should be understood that when X in the chemical formula of the halide solid electrolyte is Cl, or Br, or Cl and Br, the performance of the halide solid electrolyte is better.

[0060] The solid-state battery provided by the present invention uses a halide electrolyte with higher ionic conductivity, thereby making the solid-state battery have more superior electrochemical properties, such as lower interfacial impedance, better cycle performance and higher energy density.

[0061] The second embodiment of the present invention provides a preparation method of a halide solid electrolyte in a solid-state battery. Please refer to the preparation method of the halide solid electrolyte in the embodiment of the present invention. Figure 1 This embodiment specifically describes the implementation details of the solution. The method includes:

[0062] S101. Grind a first raw material required for preparing a halide solid electrolyte by dry grinding to obtain a first precursor powder, wherein the first raw material includes a compound containing Li, Zr, and X elements, and X includes at least one of Cl, Br, or I elements.

[0063] Exemplary dry grinding methods include ball milling or grinding with an agate mortar.

[0064] Specifically, the first raw material is part of the raw materials required to prepare the halide solid electrolyte, including a compound containing Li, Zr, and an element X, wherein X includes at least one of Cl, Br, or I. Exemplarily, the first raw material may include elements such as LiCl, LiBr, and ZrCl4.

[0065] S102. Sintering the first precursor powder in an inert atmosphere to obtain a first reactant.

[0066] The first reactant is a reactant obtained by sintering the raw materials in the first full-region powder.

[0067] In a possible implementation, the inert gas atmosphere may be at least one of nitrogen, argon, helium, and neon.

[0068] Specifically, the inert gas is any one of nitrogen, argon, helium, and neon, and can also be composed of any combination of multiple substances among the above substances, for example, it can be composed of two, three or more substances. This embodiment of the present invention does not specifically limit this.

[0069] In a possible implementation, the sintering temperature is 100-400°C.

[0070] Specifically, the sintering temperature is, for example, 100°C, 125°C, 150°C, 175°C, 200°C, 225°C, 250°C, 275°C, 300°C, 325°C, 350°C, 375°C, 400°C, or any two of the foregoing values ​​are selected to form a new range, and the value taken within the new range.

[0071] As a preferred solution, the sintering temperature is 150-350° C. Specifically, the sintering temperature is preferably any value within the range of 150-350° C.

[0072] In a possible implementation, the sintering time is 1 to 40 hours.

[0073] Specifically, the sintering time is, for example, 1h, 2.5h, 5h, 7.5h, 10h, 12.5h, 15h, 17.5h, 20h, 22.5h, 25h, 27.5h, 30h, 32.5h, 35h, 37.5h, 40h, or any two of the foregoing values ​​are selected to form a new range, and the value taken within the new range.

[0074] As a preferred solution, the sintering time is 1 to 30 hours. Specifically, the sintering time is preferably any value within the range of 1 to 30 hours.

[0075] S103. Mix the first reactant with the second raw material, and grind the mixture by dry grinding to obtain a second precursor powder, wherein the second raw material includes a compound containing the element M, and M includes at least one of the elements Y, In, Sc or Yb.

[0076] In this step, the dry grinding method is continued to be adopted to mix and grind the first reactant and the second raw material to obtain a second precursor powder.

[0077] Specifically, the second raw material is the remaining raw material required for preparing the halide solid electrolyte except for the first raw material, including a compound containing an M element, wherein M includes Y, In, Sc, or Yb. Exemplarily, the second raw material may include InCl3 and / or YCl3, etc.

[0078] S104. Sintering the second precursor powder in an inert atmosphere to obtain a halide solid electrolyte.

[0079] In this step, the precursor powder needs to be sintered to allow the second raw material and the first reactant to complete the remaining reaction, thereby obtaining a halide solid electrolyte.

[0080] In a possible implementation, the sintering temperature is 100-400°C.

[0081] Specifically, the sintering temperature is, for example, 100°C, 125°C, 150°C, 175°C, 200°C, 225°C, 250°C, 275°C, 300°C, 325°C, 350°C, 375°C, 400°C, or any two of the foregoing values are selected to form a new range, and the value taken within the new range.

[0082] As a preferred solution, the sintering temperature is 150 - 350°C. Specifically, the sintering temperature is preferably any value taken within the range of 150 - 350°C.

[0083] In a possible implementation, the sintering time is 1 - 40 h.

[0084] Specifically, the sintering time is, for example, 1 h, 2.5 h, 5 h, 7.5 h, 10 h, 12.5 h, 15 h, 17.5 h, 20 h, 2^{2.5} h, 25 h, 27.5 h, 30 h, 32.5 h, 35 h, 37.5 h, 40 h, or any two of the foregoing values are selected to form a new range, and the value taken within the new range.

[0085] As a preferred solution, the sintering time is 1 - 30 h. Specifically, the sintering time is preferably any value taken within the range of 1 - 30 h.

[0086] It should be understood that the sintering temperature and sintering time in the above steps S102 and S104 may be the same or different, and the values of the sintering temperature and time can be determined according to the actual application situation.

[0087] In the specific implementation of this solution, the chemical general formula of the halide solid electrolyte can be , where 0 ≤ a ≤ 6, 0 < b ≤ 3, 0 < c ≤ 3, 0 < d ≤ 8.

[0088] The preparation method of the halide solid electrolyte provided by the present invention enables some of the raw materials to be fully refined, evenly contacted, and undergo preliminary reactions by means of grinding and calcining the raw materials in two batches, thereby reducing the difficulty of mixing and reacting between this part of the raw materials and the remaining part of the raw materials, and thus greatly improving the mixing uniformity and reaction completion degree between the raw materials, achieving the effect of increasing the ionic conductivity of the halide solid electrolyte.

[0089] Example 3 of the present invention provides a halide solid electrolyte prepared by using the above preparation method, and the chemical general formula of the halide solid electrolyte is .

[0090] Among them, 0 ≤ a ≤ 6, 0 < b ≤ 3, 0 < c ≤ 3, 0 < d ≤ 8, M includes at least one of Y, In, Sc or Yb elements, and X includes at least one of Cl, Br or I elements. Note: In the translation of item , "2^{2.5}" is used to represent "22.5" in the original text because there seems to be a formatting issue in the original text where "22.5" is written in a non-standard way. If this is not what you intended, please provide more context or clarify the original text.

[0091] It should be understood that a, b, c and d in the prepared halide solid electrolyte are determined according to the configuration ratio of each raw material.

[0092] For example, the halide solid electrolyte may be Li 2.85 Y 0.85 Zr 0.15 Cl6、Li 2.9 In 0.9 Zr 0.1 Cl6 and Li 2.75 In 0.75 Zr 0.25 Cl6 etc.

[0093] As a preferred solution, 1≤a≤3.5; and / or, 0≤b≤1.5; and / or, 0≤c≤1.5; and / or, 3.5≤d≤7.5.

[0094] It should be understood that when a in the chemical formula of the halide solid electrolyte is taken from any value of 1 to 3.5; and / or b is taken from any value of 0 to 1.5; and / or c is taken from any value of 0 to 1.5; and / or d is taken from any value of 3.5 to 7.5, the performance of the halide dielectric is better, for example, it has higher ionic conductivity.

[0095] As a preferred solution, M includes In and / or Y. It should be understood that when M in the chemical formula of the halide solid electrolyte is In, or Y, or In and Y, the performance of the halide solid electrolyte is better.

[0096] As a preferred solution, X includes Cl and / or Br. It should be understood that when X in the chemical formula of the halide solid electrolyte is Cl, or Br, or Cl and Br, the performance of the halide solid electrolyte is better.

[0097] The halide solid electrolyte provided by the present invention is doped with the Zr element and has higher ionic conductivity than conventional halide solid electrolytes. In addition, the halide solid electrolyte provided by this embodiment is prepared by the above-mentioned preparation method, which has the effect of improving the ionic conductivity of the halide solid electrolyte, so that the ionic conductivity of the halide solid electrolyte provided by this embodiment is further improved.

[0098] A fourth embodiment of the present invention provides an electrical device, comprising an electrical device body and the all-solid-state battery provided by the present invention.

[0099] It should be noted that the present invention does not specifically limit the type of electrical device, which can be any electrical device that includes the battery, including but not limited to electric vehicles, mobile phones, portable devices, laptops, electric bicycles, electric toys, energy storage devices, etc.

[0100] The present invention is further described below through specific examples.

[0101] Example 1

[0102] Preparation of halide solid electrolytes:

[0103] (1) The first raw material LiCl and ZrCl4 were weighed in a molar ratio of 2.8:0.2, added to an agate mortar, and ground by dry grinding for 30 minutes to obtain a first precursor powder;

[0104] (2) In a nitrogen atmosphere, the first precursor powder is sintered in a heat treatment furnace to obtain a chemical composition of Li 2.8 Zr 0.2 Cl 3.6 The first reactant;

[0105] (3) Add the first reactant to an agate mortar, then weigh 0.8 mol of the second raw material InCl3 and add it to the mortar, and continue grinding for 30 minutes to obtain the second precursor powder;

[0106] (4) In a nitrogen atmosphere, the second precursor powder is sintered in a heat treatment furnace to obtain a chemical composition of Li 2.8 In 0.8 Zr 0.2 Cl6 halide solid electrolyte.

[0107] Example 2

[0108] Preparation of halide solid electrolytes:

[0109] The difference from Example 1 is that the composition and ratio of the first raw material and the second raw material are changed so that the chemical composition of the first reaction is Li 2.9 Zr 0.1 Cl 3.3 , the chemical composition of the second reactant is Li 2.9 In 0.9 Zr 0.1 Cl6.

[0110] Example 3

[0111] Preparation of halide solid electrolytes:

[0112] The difference from Example 1 is that the composition and ratio of the first raw material and the second raw material are changed so that the chemical composition of the first reactant is Li 2.85 Zr 0.15 Cl 3.45 , the chemical composition of the second reactant is Li 2.85 In 0.85 Zr 0.15 Cl6.

[0113] Example 4

[0114] Preparation of halide solid electrolytes:

[0115] The difference from Example 1 is that the composition and ratio of the first raw material and the second raw material are changed so that the chemical composition of the first reactant is Li 2.75 Zr 0.25 Cl 3.75 , the chemical composition of the second reactant is Li 2.75 In 0.75 Zr 0.25 Cl6.

[0116] Example 5

[0117] Preparation of halide solid electrolytes:

[0118] The difference from Example 1 is that the composition and ratio of the first raw material and the second raw material are changed so that the chemical composition of the first reactant is Li 2.85 Zr 0.15 Cl 3.45 , the chemical composition of the second reactant is Li 2.85 Y 0.85 Zr 0.15 Cl6.

[0119] Example 6

[0120] Preparation of halide solid electrolytes:

[0121] The difference from Example 1 is that the composition and proportion of the second raw material are changed so that the chemical composition of the second reactant is Li 2.8 Y 0.8 Zr 0.2 Cl6.

[0122] Example 7

[0123] Preparation of halide solid electrolytes:

[0124] The difference from Example 1 is that the composition and proportion of the second raw material are changed so that the chemical composition of the second reactant is Li 2.8 Sc 0.8 Zr 0.2 Cl6.

[0125] Example 8

[0126] Preparation of halide solid electrolytes:

[0127] The difference from Example 1 is that the composition and proportion of the second raw material are changed so that the chemical composition of the second reactant is Li 2.8 Yb 0.8 Zr 0.2 Cl6.

[0128] Example 9

[0129] Preparation of halide solid electrolytes:

[0130] The difference from Example 1 is that the composition and proportion of the second raw material are changed so that the chemical composition of the second reactant is Li 2.8 In 0.8 Zr 0.2 Cl 5.5 Br 0.5 .

[0131] Example 10

[0132] Preparation of halide solid electrolytes:

[0133] The difference from Example 1 is that the composition and proportion of the second raw material are changed so that the chemical composition of the second reactant is Li 2.8 Y 0.8 Zr 0.2 Cl5Br.

[0134] Comparative Example 1

[0135] Preparation of halide solid electrolytes:

[0136] (1) Raw materials LiCl, ZrCl 4、 InCl3 was weighed in a molar ratio of 2.8:0.2:0.8, added to an agate mortar, and ground using a dry grinding method for 30 minutes to obtain a precursor powder;

[0137] (2) In a nitrogen atmosphere, the precursor powder is sintered in a heat treatment furnace to obtain a chemical composition of Li 2.8 In 0.8 Zr 0.2 Cl6 halide solid electrolyte.

[0138] Comparative Example 2

[0139] Preparation of halide solid electrolytes:

[0140] The difference from Comparative Example 1 is that the composition and proportion of the raw materials are changed so that the chemical composition of the halide solid electrolyte is Li 2.8 Y 0.8 Zr 0.2 Cl6.

[0141] Comparative Example 3

[0142] Preparation of halide solid electrolytes:

[0143] The difference from Comparative Example 1 is that the composition and proportion of the raw materials are changed so that the chemical composition of the halide solid electrolyte is Li 2.8 Sc 0.8 Zr 0.2 Cl6.

[0144] The ion conductivity of the halide solid electrolytes prepared in the above examples and comparative examples was tested. The test results are shown in Table 1. The test method is as follows:

[0145] 1) Weigh 100 mg of halide solid electrolyte powder and place it in a pressurized mold. Pressurize the powder at 300 MPa. While the pressure is applied, measure the impedance of the electrolyte material at room temperature (25°C) using an electrochemical workstation (Solarton 1260) and electrochemical impedance spectroscopy.

[0146] 2) The real value of the impedance at the measurement point where the absolute value of the phase of the plurality of impedances is the smallest is taken as the resistance value RSE of the electrolyte material with respect to ion conduction;

[0147] 3) Using the resistance value RSE, based on the formula , calculate the ionic conductivity of the halide solid electrolyte, where σ is the ionic conductivity, RSE is the measured resistance of the electrolyte material relative to ionic conduction, S is the surface area of ​​the electrolyte material under pressure, and t is the thickness of the electrolyte material under pressure.

[0148] Table 1: Ionic conductivity test results of Examples and Comparative Examples

[0149]

[0150] According to the data in Table 1, the room temperature ionic conductivity of the halide solid electrolytes corresponding to Examples 1-10 is significantly higher than that of Comparative Examples 1-3, especially Example 1 and Comparative Example 1, Example 6 and Comparative Example 2, and Example 7 and Comparative Example 3. When the chemical components of the prepared halide solid electrolytes are the same, the room temperature ionic conductivity of the halide solid electrolytes corresponding to the examples is significantly higher than that of the comparative examples. It can be seen that the preparation method provided by the present invention can effectively improve the ionic conductivity of the halide solid electrolyte.

[0151] Based on this, the solid-state battery provided by the present invention also has more superior electrochemical performance because it includes a halide electrolyte with higher ionic conductivity.

[0152] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A solid-state battery, characterized in that: Comprising: a positive electrode sheet, a halide solid electrolyte, and a negative electrode sheet; wherein, the halide solid electrolyte is prepared by the following method: grinding a first raw material required for preparing the halide solid electrolyte by dry grinding to obtain a first precursor powder, wherein the first raw material includes a compound containing Li, Zr, and X elements, and X includes at least one of Cl, Br, or I elements; sintering the first precursor powder in an inert atmosphere to obtain a first reactant; mixing the first reactant with a second raw material, and grinding the mixture by dry grinding to obtain a second precursor powder, wherein the second raw material includes a compound containing M elements, and M includes at least one of Y, In, Sc, or Yb elements; sintering the second precursor powder in an inert atmosphere to obtain the halide solid electrolyte.

2. The solid-state battery according to claim 1, characterized in that The general chemical formula of the halide solid electrolyte is ; where 0≤a≤6, 0<b≤3, 0<c≤3, 0<d≤8, M includes at least one of Y, In, Sc, or Yb elements, and X includes at least one of Cl, Br, or I elements.

3. The solid-state battery according to claim 2, characterized in that 1≤a≤3.5; and / or, 0≤b≤1.5; and / or, 0≤c≤1.5; and / or, 3.5≤d≤7.

5.

4. The solid-state battery according to claim 2, characterized in that The M includes In and / or Y; the X includes Cl and / or Br.

5. A method for preparing a halide solid electrolyte in a solid-state battery, characterized in that: Comprising: grinding a first raw material required for preparing the halide solid electrolyte by dry grinding to obtain a first precursor powder; sintering the first precursor powder in an inert atmosphere to obtain a first reactant; mixing the first reactant with a second raw material, and grinding the mixture by dry grinding to obtain a second precursor powder; sintering the second precursor powder in an inert atmosphere to obtain the halide solid electrolyte; wherein, the first raw material includes a compound containing Li, Zr, and X elements, and X includes at least one of Cl, Br, or I elements; the second raw material includes a compound containing M elements, and M includes at least one of Y, In, Sc, or Yb elements.

6. The method according to claim 5, characterized in that [[ID= 7. The method according to claim 5, characterized in that ​ 8. The method according to any one of claims 5 to 7, characterized in that ​ 9. A halide solid electrolyte obtained according to the preparation method according to any one of claims 5 to 8, characterized in that: The general chemical formula of the halide solid electrolyte is ; ​ 10. The halide solid electrolyte according to claim 9, characterized in that ​ 11. The halide solid electrolyte according to claim 10, characterized in that ​

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