Halide solid electrolyte, preparation method thereof and solid-state battery

Abstract

The invention discloses a halide solid electrolyte, a preparation method thereof and a solid-state battery, and relates to the technical field of batteries. The chemical formula of the halide solid electrolyte is LigMhNiXjOk, and M and N are at least one of Si, Ta, Nb, Hf, Zr, Y, Sc, In, Al and La respectively; x is a halogen element; the preparation method comprises the following steps: carrying out ball milling on LiaNOb and MXc in a protective atmosphere to obtain the halide solid electrolyte. A lithium salt precursor of a traditional halide solid electrolyte material is changed, polyanion salt of rare earth elements of Si, Ta, Nb, Hf, Zr, Y, Sc, In, Al and La is adopted as the lithium salt precursor, the variety of halide solid electrolytes is expanded, and the ionic conductivity of the halide solid electrolytes is improved; and the assembled total battery is excellent in interface contact and more excellent in cycling stability and rate capability.

Description

TECHNICAL FIELD

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

[0002] With the rapid development of electrochemical energy storage technology, the current commercial liquid battery has basically reached its upper limit of energy density, and it also has serious safety hazards. To meet the growing demand for high specific energy and high safety, it is a great challenge for the current lithium-ion battery technology. Solid-state batteries are an effective solution, but their development is limited by solid-state electrolytes (SSE).

[0003] Among the many solid-state electrolyte systems, halide SSEs perform the most balanced in terms of electrochemical window, compaction density, forming process, air stability, ionic conductivity, etc., and are favorable candidates for solid-state electrolytes for all-solid-state batteries. However, existing halide solid-state electrolytes have a single composition of lithium salt precursors, only LiX (X = F, Cl, Br, I), Li2O, etc., resulting in limited types of electrolytes. In particular, the ionic conductivity of existing halide solid-state electrolytes is generally not high (less than 2 mS / cm), and it is necessary to further improve the ionic conductivity. However, the current synthesis strategy based on single-anion precursors cannot break through this bottleneck. SUMMARY

[0004] The present application aims to at least solve one of the technical problems in the prior art, and provides a halide solid-state electrolyte, a preparation method thereof and a solid-state battery.

[0005] In order to solve the problems in the prior art using a single-anion precursor synthesis strategy, the applicant has studied the use of polyanion salt Li n YO m (Y = C, P, S, etc.) to synthesize solid-state electrolytes, but polyanion salt Li n YO m (Y = C, P, S, etc.) compared to traditional LiX, although it expands the types of lithium salts, but its ionic conductivity is low, and in practical use, it is not as good as LiX as a precursor of electrolyte material. In addition, the single nature of this lithium salt also leads to the modification of halide electrolytes, which largely depends on the doping of different metal halides, such as introducing NX a MCl d into Li z MN a Cl c X d e ​The structure of the halide solid-state electrolyte is similar to that of (M, N=Ta, Zr, In, Hf, Al, La-based rare earth elements, etc.), but the metal halide doping method is single, which greatly limits the improvement of the performance of the halide electrolyte.

[0006] Therefore, the applicant has found, through further research, that using Si, Ta, Nb, Hf, Zr, Y, Sc, In, Al, La-based rare earth element polyanion salts as lithium salt precursors not only greatly expands the types of halide solid-state electrolytes, but also provides new options for the modification of traditional electrolytes, and greatly improves the ionic conductivity of halide solid-state electrolytes.

[0007] The technical solutions of the present application are as follows:

[0008] In a first aspect, the present application provides a halide solid-state electrolyte, the chemical formula of the halide solid-state electrolyte being Li g M h N i X j O k , wherein M and N are at least one of Si, Ta, Nb, Hf, Zr, Y, Sc, In, Al, and La; X is a halogen element; 0.4≤g≤3; 0.2≤h≤1, 1 / 12≤i≤1 / 2; 2≤j≤6; 0.8≤k≤6.

[0009] As a preferred embodiment, 0.6≤g / k≤2.

[0010] As a preferred embodiment, the raw materials for preparing the halide solid-state electrolyte include Li a NO b and MX c , wherein 1≤a≤7; 2≤b≤7; 2≤c≤6.

[0011] As a preferred embodiment, the raw materials for preparing the halide solid-state electrolyte further include M e O f , wherein 1≤e≤5; 1≤f≤5.

[0012] As a preferred embodiment, the halide solid-state electrolyte is LiTaSi 0.25 Cl5O, Li 0.8 TaSi 0.2 Cl5O 0.8 , Li 1.2 TaSi 0.3 Cl5O 1.2 , LiZrSi 0.2 Cl4O, Li 7 / 6 TaNb 1 / 6 Cl5O, LiTa 0.8 Hf0.2 Si 0.25 Cl 4.8 O and LiTaSi 0.25 Cl4O 1.5 .

[0013] Secondly, the present invention provides a method for preparing the halide solid electrolyte, the method comprising the following steps:

[0014] Under a protective atmosphere, Li a NO b With MX c Ball milling was performed to obtain a halide solid electrolyte;

[0015] Where 1≤a≤7; 2≤b≤7; 2≤c≤6.

[0016] The present invention also provides another method for preparing the halide solid electrolyte, the method comprising the following steps:

[0017] Under a protective atmosphere, Li a NO b With MX c M e O f Ball milling was performed to obtain a halide solid electrolyte;

[0018] Where 1≤a≤7; 2≤b≤7; 2≤c≤6; 1≤e≤5; 1≤f≤5.

[0019] As a preferred implementation scheme, Li a NO b With MX c The molar ratio of added ingredients is 0.3–5:1–6.

[0020] As a preferred embodiment, the ball milling method includes: first performing low-speed ball milling, and then performing high-speed ball milling;

[0021] The ball-to-material ratio is (15-40):1. The low-speed ball milling speed is 80rpm-120rpm and the low-speed ball milling time is 20min-40min. The high-speed ball milling speed is 400rpm-600rpm and the high-speed ball milling time is 6h-128h.

[0022] Thirdly, the present invention provides a solid-state battery, comprising the halide solid electrolyte or the halide solid electrolyte obtained by the preparation method described above.

[0023] This invention has at least one of the following beneficial effects:

[0024] 1. The lithium salt precursor of the traditional halide solid electrolyte material is changed, the polyanion salt of Si, Ta, Nb, Hf, Zr, Y, Sc, In, Al, La rare earth elements is used as the lithium salt precursor, the variety of the halide solid electrolyte is greatly expanded, meanwhile, the traditional electrolyte modification is provided with new selection, and the ion conductivity of the halide solid electrolyte is effectively improved. The halide solid electrolyte material prepared in the application has higher ion conductivity and wider electrochemical window; the full battery assembled has excellent interface contact, and the cycle stability and rate performance are more excellent.

[0025] 2. The local configuration of the solid electrolyte can be adjusted by introducing O as a bridging structure in the lithium salt precursor A (Li a NO b );Different from the bridging oxygen introduced by Li2O, one end of the bridging oxygen introduced in the lithium salt precursor of the application itself has N element, and forms N-O-M structure with the precursor B (MX c ), which will affect the bond length and coordination of M-X, and through this one-time introduction mechanism, the ultra-high ion conductivity is realized. In addition, the N (Si, Ta, Nb, Hf, Zr, Y, Sc, In, Al, La rare earth elements) in the lithium salt precursor of the application is different from the traditional C, P, S and other elements, and the bond strength of N-O is greatly different from C-O, S-O and P-O, therefore, compared with the polyanion salt containing C, P, S and other elements, the conductivity of the halide solid electrolyte material prepared by the lithium salt precursor of the application is higher.

[0026] 3. The lithium salt precursor of the application has better water and oxygen stability compared with the traditional lithium salt precursor, the synthesis process is very simple, the price is far lower than that of LiCl, Li2O and other materials, and has better commercialization prospect. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 The electron microscope graph of the halide solid electrolyte synthesized in Example 1.

[0028] Figure 2 The electron microscope graph of the halide solid electrolyte synthesized in Example 9.

[0029] Figure 3 The electron microscope graph of the halide solid electrolyte synthesized in Example 10.

[0030] Figure 4 The impedance spectrum graph of the battery assembled by the halide solid electrolyte in Example 1.

[0031] Figure 5 The impedance spectrum graph of the battery assembled by the halide solid electrolyte in Example 2.

[0032] Figure 6 The impedance spectrum of the battery assembled with halide solid electrolyte in Example 3 is shown.

[0033] Figure 7 The impedance spectrum of the battery assembled with halide solid electrolyte in Example 4 is shown.

[0034] Figure 8 The impedance spectrum of the battery assembled with halide solid electrolyte in Example 5 is shown.

[0035] Figure 9 The impedance spectrum of the battery assembled with halide solid electrolyte in Example 6 is shown.

[0036] Figure 10 The impedance spectrum of the battery assembled with halide solid electrolyte in Example 7 is shown.

[0037] Figure 11 The impedance spectrum of the battery assembled with halide solid electrolyte in Example 8 is shown.

[0038] Figure 12 The impedance spectrum of the battery assembled with the halide solid electrolyte in Example 9 is shown.

[0039] Figure 13 The impedance spectrum of the battery assembled with halide solid electrolyte in Example 10 is shown.

[0040] Figure 14 The impedance spectrum of the battery assembled with halide solid electrolyte in Example 11 is shown.

[0041] Figure 15 The impedance spectrum of the battery assembled with halide solid electrolyte in Example 12 is shown.

[0042] Figure 16 The electrochemical performance of the all-solid-state battery assembled with the halide solid electrolyte in Example 1 is shown.

[0043] Figure 17 The X-ray diffraction patterns are those of the halide solid electrolytes in Examples 1, 4, and 5. Detailed Implementation

[0044] To make the technical problems solved, the technical solutions, and the beneficial effects of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0045] One embodiment of the present invention provides a halide solid electrolyte, wherein the chemical formula of the halide solid electrolyte is Li. g M h N i Xj O k Where M and N are at least one of Si, Ta, Nb, Hf, Zr, Y, Sc, In, Al, and La; X is a halogen element; 0.4≤g≤3; 0.2≤h≤1, 1 / 12≤i≤1 / 2; 2≤j≤6; 0.8≤k≤6.

[0046] This invention not only greatly expands the types of halide solid electrolytes but also effectively improves their ionic conductivity. Compared to existing halide solid electrolytes, the halide solid electrolyte material prepared by this invention has higher ionic conductivity and a wider electrochemical window; the assembled full cell exhibits excellent interfacial contact and superior cycle stability and rate performance.

[0047] In some embodiments, 0.6 ≤ g / k ≤ 2.

[0048] In some embodiments, the raw materials for preparing the halide solid electrolyte include Li a NO b With MX c , where 1≤a≤7; 2≤b≤7; 2≤c≤6.

[0049] In some embodiments, the raw materials for preparing the halide solid electrolyte further include M. e O f , where 1≤e≤5; 1≤f≤5.

[0050] In some embodiments, X includes one or more of F, Cl, Br, and I.

[0051] In some embodiments, the halide solid electrolyte is LiTaSi. 0.25 Cl5O, Li 0.8 TaSi 0.2 Cl5O 0.8 Li 1.2 TaSi 0.3 Cl5O 1.2 LiZrSi 0.2 Cl4O, Li 7 / 6 TaNb 1 / 6 Cl5O, LiTa 0.8 Hf 0.2 Si 0.25 Cl 4.8 O and LiTaSi 0.25 Cl4O 1.5 .

[0052] Another embodiment of the present invention provides a method for preparing the halide solid electrolyte, comprising the following steps:

[0053] Under a protective atmosphere, Li a NO b With MX c Ball milling was performed to obtain a halide solid electrolyte;

[0054] Where 1≤a≤7; 2≤b≤7; 2≤c≤6.

[0055] Unlike traditional single-anion lithium salts LiX (X = F, Cl, Br, I) and Li₂O used as lithium salt precursors for halide solid electrolyte materials, this invention adopts a method with the chemical formula satisfying Li a NO b Metal compounds (Li4SiO4, Li7NbO6, Li2WO4, etc.) serve as lithium salt precursor A, through reaction with MX c (Precursor B) was subjected to high-energy ball milling to synthesize Li. g M h N i X j O k Solid electrolyte (M, N = Si, P, Ta, Nb, Hf, Zr, Y, Sc, In, Al, La series rare earth elements; X is a halogen element). The local configuration of the solid electrolyte is adjusted by introducing O as a bridging structure in precursor A; unlike the bridging oxygen introduced through Li₂O, one end of the bridging oxygen introduced in lithium salt precursor A itself contains N element, which interacts with precursor B (MX). c The formation of NOM structures will affect MX. c The bond lengths and coordination configurations are determined through this one-time introduction mechanism to achieve ultra-high ionic conductivity. Furthermore, the N in the lithium salt precursor A differs from traditional elements such as C, P, and S, and the bond strength of NO differs significantly from that of CO, SO, and PO. Therefore, polyanionic salts containing elements such as C, P, and S may also satisfy the chemical formula structure mentioned in this application, but they cannot achieve a significant increase in conductivity.

[0056] In some embodiments, the preparation method includes the following steps:

[0057] Under a protective atmosphere, Li a NO b With MX c M e O f Ball milling was performed to obtain a halide solid electrolyte;

[0058] Where 1≤e≤5; 1≤f≤5.

[0059] By adding a small amount of oxygen-containing compound M e O f (Precursor C) regulation can change the proportion of O.

[0060] In some embodiments, Li a NO b With MX c The molar ratio of added ingredients is 0.3–5:1–6.

[0061] In some embodiments, the ball milling method includes: first performing low-speed ball milling, and then performing high-speed ball milling;

[0062] The ball-to-material ratio is (15-40):1. The low-speed ball milling speed is 80rpm-120rpm and the low-speed ball milling time is 20min-40min. The high-speed ball milling speed is 400rpm-600rpm and the high-speed ball milling time is 6h-128h.

[0063] In some embodiments, it is prepared by the following method:

[0064] a. Under an inert atmosphere, two precursors are placed in a ball mill jar according to a certain element ratio; wherein the ball-to-material ratio is (15-40):1.

[0065] b. Seal the ball mill jar and perform high-energy ball milling. The ball mill speed is 400-600 rpm / min, and the ball milling time is 6-128 hours. The optimal ball milling time varies depending on the precursor.

[0066] c. After ball milling, open the ball mill jar under an inert atmosphere and sieve to obtain the solid electrolyte material required by this invention.

[0067] This invention adopts the chemical formula satisfying Li a NO b Metal compounds are used as precursor A, where a and b are related to the valence state and structure of N. Precursors that satisfy the above chemical formula are all within the scope of protection of this application. (This is related to MX...) c (Precursor B) is subjected to high-energy ball milling to synthesize a solid electrolyte. If necessary, a small amount of oxygen-containing compound M can be added. e O f (Precursor C) regulation.

[0068] Another embodiment of the present invention provides a solid-state battery, comprising the halide solid electrolyte or the halide solid electrolyte obtained by the preparation method described above.

[0069] The full battery assembled using the halide solid electrolyte of the present invention has excellent interfacial contact and superior cycle stability and rate performance.

[0070] The present invention will be further described in detail below with reference to specific embodiments, but the present invention is not limited to the following specific embodiments.

[0071] Example 1

[0072] Under an argon atmosphere, Li4SiO4 (precursor A) and TaCl5 (precursor B) were mixed in a molar ratio of 1:4 to obtain a mixture.

[0073] The mixture was placed in the grinding jar of a high-energy ball mill with a ball-to-material ratio of 30:1. 5mm zirconia grinding beads were used. The grinding jar was sealed under an argon atmosphere and then placed in the ball mill for grinding. First, the ball mill was ground at a low speed of 100 rpm for 30 minutes, followed by high-speed grinding at 500 rpm for 10 minutes, with a 10-minute rest period. The total grinding time was 12 hours.

[0074] After ball milling, the milling jar is opened under an argon atmosphere to obtain the halide solid electrolyte LiTaSi. 0.25 Cl5O.

[0075] Figure 1 The image shown is an electron microscope image of the solid electrolyte prepared in Example 1. The electron microscope image shows that the particle size distribution is uniform and the material texture is relatively loose.

[0076] Example 2

[0077] This embodiment is basically the same as Embodiment 1, except that in this embodiment, Li4SiO4 (precursor A) and TaCl5 (precursor B) are mixed in a molar ratio of 1:5, and the halide solid electrolyte in this embodiment is Li 0.8 TaSi 0.2 Cl5O 0.8 .

[0078] Example 3

[0079] This embodiment is basically the same as Embodiment 1, except that in this embodiment, Li4SiO4 (precursor A) and TaCl5 (precursor B) are mixed in a molar ratio of 0.3:1, and the halide solid electrolyte in this embodiment is Li 1.2 TaSi 0.3 Cl5O 1.2 .

[0080] Example 4

[0081] This embodiment is basically the same as Embodiment 1, except that the ball milling time is 6 hours in this embodiment.

[0082] Example 5

[0083] This embodiment is basically the same as Embodiment 1, except that the ball milling time is 18 hours in this embodiment.

[0084] Example 6

[0085] This embodiment is basically the same as Embodiment 1, except that the ball milling time is 60 hours in this embodiment.

[0086] Example 7

[0087] This embodiment is basically the same as Embodiment 1, except that the ball mill speed of the high-speed ball mill is 400 rpm / min.

[0088] Example 8

[0089] This embodiment is basically the same as Embodiment 1, except that the ball mill speed in this embodiment is 600 rpm / min.

[0090] Example 9

[0091] This embodiment is basically the same as Embodiment 1, except that in this embodiment, precursor B is replaced with ZrCl4 and mixed with Li4SiO4 (precursor A) at a molar ratio of 1:5, and the ball milling time is 60 hours. The halide solid electrolyte in this embodiment is LiZrSi 0.2 Cl4O.

[0092] Figure 2 The image shown is an electron microscope image of the solid electrolyte prepared in Example 9. The electron microscope image shows that the Zr-based material has a relatively high density and pores appear on the surface of the material.

[0093] Example 10

[0094] This embodiment is basically the same as Embodiment 1, except that in this embodiment, precursor A is replaced with Li7NbO6 and mixed with TaCl5 (precursor B) at a molar ratio of 1:6. The halide solid electrolyte in this embodiment is Li 7 / 6 TaNb 1 / 6 Cl5O.

[0095] Figure 3 The image shown is an electron microscope image of the solid electrolyte prepared in Example 10. It can be seen from the electron microscope image that the Nb doped material is similar to the material described in Example 1, and the particle size distribution is also basically the same.

[0096] Example 11

[0097] This embodiment is basically the same as Embodiment 1, except that in this embodiment, Li4SiO4 (precursor A), TaCl5 (precursor B), and HfCl4 (precursor B) are mixed in a molar ratio of 0.25:0.8:0.2, and the halide solid electrolyte in this embodiment is LiTa 0.8 Hf 0.2 Si 0.25 Cl 4.8 O.

[0098] Example 12

[0099] This embodiment is basically the same as Embodiment 1, except that in this embodiment, Li4SiO4 (precursor A), TaCl5 (precursor B), and Ta2O5 (precursor C) are mixed in a molar ratio of 0.25:0.8:0.1, and the halide solid electrolyte in this embodiment is LiTaSi. 0.25 Cl4O 1.5 .

[0100] Comparative Example 1

[0101] Comparative Example 1 uses conventional monoanion lithium salts LiX (X = F, Cl, Br, I) and Li2O as lithium salt precursors for halide solid electrolyte materials. This comparative example is basically the same as Example 1, except that in this example, Li2O (precursor A) and TaCl5 (precursor B) are mixed in a molar ratio of 1.6:1, and the halide solid electrolyte in this comparative example is 1.6Li2O-TaCl5.

[0102] Comparative Example 2

[0103] Comparative Example 1 uses conventional single-anion lithium salts LiX (X = F, Cl, Br, I), Li2O, and SiO2 as lithium salt precursors for the halide solid electrolyte material. This comparative example is basically the same as Example 1, except that in this example, Li2O (precursor A), SiO2 (precursor A), and TaCl5 (precursor B) are mixed in a molar ratio of 0.5:0.25:1, and the halide solid electrolyte in this comparative example is LiTaSi. 0.25 Cl5O.

[0104] Performance testing:

[0105] 1. The ionic conductivity of the halide solid electrolytes prepared in Examples 1-12 and Comparative Examples 1-2 were tested respectively. The test results are shown in Table 1.

[0106] The test method is as follows: In an argon atmosphere, under a pressure of 300 MPa, 120 mg of electrolyte powder is placed in a mold battery and pressed into a sheet with a diameter of 10 mm and a thickness between 400-540 μm, and then an electrochemical impedance test is performed.

[0107] Table 1

[0108]

[0109]

[0110] As can be seen from Table 1, the solid electrolytes synthesized in Examples 1-12 all have high ionic conductivity. Among them, the solid electrolytes synthesized in Examples 1, 5 and 12 have ionic conductivity greater than 10 mS / cm, which is much higher than the conductivity of solid electrolytes in the prior art.

[0111] A comparison between Examples 1-12 and Comparative Examples 1-2 shows that:

[0112] A comparison between Examples 1-3 confirms that different halide solid electrolytes prepared with different ratios of precursors A and B all exhibit high ionic conductivity.

[0113] A comparison between Examples 1, 4, 5, and 6 confirms that the difference in ball milling time affects the ionic conductivity of the synthesized solid electrolyte. A ball milling time of 12-18 hours is more suitable, as both excessively long and short ball milling times will affect the ionic conductivity of the synthesized solid electrolyte.

[0114] A comparison between Examples 1, 7, and 8 confirms that the difference in ball milling speed affects the ionic conductivity of the synthesized solid electrolyte. A ball milling speed of 500 rpm to 600 rpm is more suitable, while a ball milling speed that is too low will affect the ionic conductivity of the synthesized solid electrolyte.

[0115] A comparison between Examples 1 and 12 confirms that adding a small amount of oxygen-containing compound M... e O f (Precursor C) can regulate the O ratio, and the oxygen ratio affects the ionic conductivity of halide solid electrolytes;

[0116] A comparison between Example 1 and Comparative Example 1 confirms that the performance difference between the present invention and the best conventional electrolyte materials, namely, that using Li2O as a precursor affects the ionic conductivity of the synthesized solid electrolyte.

[0117] A comparison between Example 1 and Comparative Example 2 confirms that, compared to using Li a NO b Using Li2O and SiO2 as precursors, the solid electrolytes with the same structure synthesized by these precursors showed significantly lower conductivity, indicating that the type of precursor affects the ionic conductivity of the synthesized solid electrolytes.

[0118] 2. Battery performance test:

[0119] The solid electrolytes synthesized in Examples 1-12 were combined with LiNi 0.8 Mn 0.1 Co 0.1The O2 positive electrode was manually mixed in a mortar to prepare a mixed positive electrode. Subsequently, an electrolyte sheet was pressed into a mold battery, and the mixed positive electrode and Li-In alloy negative electrode were placed on either side of the electrolyte sheet to prepare an all-solid-state battery. The battery achieved an initial discharge capacity of 125 mAh / g at a rate of 20C and retained more than 95% of its capacity after 500 cycles. Test results are shown below. Figures 4-17 .

[0120] Figures 4-15 The impedance spectra of Examples 1-12 are shown; by Figures 4-15 It can be seen that the solid electrolytes prepared in Examples 1-12 have low impedance and good ion conduction characteristics.

[0121] Figure 16 The electrochemical performance of the all-solid-state battery assembled with the electrolyte in Example 1 is shown; by Figure 16 It can be seen that the solid electrolyte prepared in Example 1 has an initial discharge capacity of 125 mAh / g at a rate of 20C and retains more than 95% of its capacity after 500 cycles, demonstrating excellent rate performance.

[0122] Figure 17 The X-ray diffraction patterns of Examples 1, 4, and 5 are shown respectively. Figure 17 It can be seen that Example 4 exhibits a crystalline structure after 6 hours of ball milling, while Examples 1 and 5 show amorphization after 12 hours and 18 hours of ball milling, respectively.

[0123] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A halide solid electrolyte, characterized in that, The chemical formula of the halide solid electrolyte is Li g M h N i X j O k Where M and N are at least one of Si, Ta, Nb, Hf, Zr, Y, Sc, In, Al, and La; X is a halogen element; 0.4≤g≤3; 0.2≤h≤1, 1 / 12≤i≤1 / 2; 2≤j≤6; 0.8≤k≤6.

2. The halide solid electrolyte according to claim 1, characterized in that, 0.6≤g / k≤2.

3. The halide solid electrolyte according to claim 1, characterized in that, The raw materials for preparing the halide solid electrolyte include Li a NO b With MX c , where 1≤a≤7; 2≤b≤7; 2≤c≤6.

4. The halide solid electrolyte according to claim 4, characterized in that, The raw materials for preparing the halide solid electrolyte also include M e O f , where 1≤e≤5; 1≤f≤5.

5. The halide solid electrolyte according to claim 1, characterized in that, The halide solid electrolyte is LiTaSi. 0.25 Cl5O, Li 0.8 TaSi 0.2 Cl5O 0.8 Li 1.2 TaSi 0.3 Cl5O 1.2 LiZrSi 0.2 Cl4O, Li 7 / 6 TaNb 1 / 6 Cl5O, LiTa 0.8 Hf 0.2 Si 0.25 Cl 4.8 O and LiTaSi 0.25 Cl4O 1.5 .

6. The method for preparing the halide solid electrolyte according to any one of claims 1 to 5, characterized in that, The preparation method includes the following steps: Under a protective atmosphere, Li a NO b With MX c Ball milling was performed to obtain a halide solid electrolyte; Where 1≤a≤7; 2≤b≤7; 2≤c≤6.

7. The method for preparing the halide solid electrolyte according to any one of claims 1 to 5, characterized in that, The preparation method includes the following steps: Under a protective atmosphere, Li a NO b With MX c M e O f Ball milling was performed to obtain a halide solid electrolyte; Where 1≤a≤7; 2≤b≤7; 2≤c≤6; 1≤e≤5; 1≤f≤5.

8. The preparation method according to claim 6 or 7, characterized in that, Li a NO b With MX c The molar ratio of added ingredients is 0.3–5:1–6.

9. The preparation method according to claim 6 or 7, characterized in that, The ball milling method includes: first performing low-speed ball milling, and then performing high-speed ball milling; The ball-to-material ratio is 15-40:1, the low-speed ball milling speed is 80rpm-120rpm, the low-speed ball milling time is 20min-40min, the high-speed ball milling speed is 400rpm-600rpm, and the high-speed ball milling time is 6h-128h.

10. A solid-state battery, characterized in that, Includes the halide solid electrolyte according to any one of claims 1 to 5 or the halide solid electrolyte obtained by the preparation method according to any one of claims 6 to 9.

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