Oxidation halide solid electrolyte, preparation method thereof and all-solid-state battery

Abstract

The invention discloses an oxyhalide solid electrolyte, a preparation method thereof and an all-solid-state battery, and relates to the technical field of batteries. The solid electrolyte is LiaMbNcXdOe, M and N are the same elements or different elements, and M and N are at least one of Zn, Ba, Al, In, Y, Cr, Ti, Zr, Hf, Nb, Ta, La, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu; x is at least one of F, Cl, Br and I. The oxyhalide solid electrolyte with high ionic conductivity and cost advantage is prepared by selecting high-valence metal oxide, halide and lithium halide through a ball milling method and combining annealing and hot pressing processes, and the oxyhalide solid electrolyte can show good electrochemical performance when being applied to all-solid-state lithium metal batteries.

Description

Technical Field

[0001] This invention relates to the field of battery technology, specifically to a halide oxide solid electrolyte, its preparation method, and an all-solid-state battery. Background Technology

[0002] With the urgent demand for high-energy-density and high-safety lithium batteries in applications such as electric vehicles, wearable devices, and large-scale energy storage, the technological bottlenecks of traditional liquid lithium-ion batteries are gradually becoming apparent. Traditional lithium-ion battery systems, constructed with graphite anodes and intercalated cathodes, have reached near-theoretical energy densities and, due to the use of flammable organic electrolytes, are prone to thermal runaway under overcharging, short-circuiting, or high-temperature conditions, posing significant safety hazards. Lithium metal, as an anode material, possesses extremely high theoretical specific capacity (3860 mAh·g). -1 With its lowest electrochemical potential, lithium metal is considered a crucial material for realizing next-generation high-energy batteries. However, lithium metal is prone to dendrite growth in liquid electrolytes, leading to internal short circuits and even thermal runaway, making it difficult to stably apply in existing systems. Therefore, all-solid-state lithium metal batteries, due to their excellent safety, energy density potential, and cycle life, have become a cutting-edge research area in the lithium battery field. All-solid-state batteries use solid electrolytes instead of traditional liquid electrolytes and separators, effectively preventing dendrite penetration and possessing advantages such as non-flammability, leak-proofness, and high thermal stability. This represents a key path for advancing lithium battery technology towards practical application and industrialization.

[0003] Solid-state electrolytes, as the core functional unit of all-solid-state batteries, directly determine the battery's electrochemical stability, power performance, and cycle life. Currently, widely studied solid-state electrolytes mainly include oxides, sulfides, polymers, and halides. In contrast, halide oxide solid-state electrolytes are becoming a research hotspot in this field due to their unique advantages in ion conduction, electrochemical window, environmental stability, and interfacial compatibility. Halide oxides are typically generated by solid-phase or liquid-phase reactions between lithium halide salts and high-valence metal halides, and the materials are rich in lattice vacancies and highly polarizable halide anions (such as F). - Cl - ,Br - I - This significantly reduces the lithium-ion migration barrier, enabling >10 at room temperature. -3 S·cm -1The high ionic conductivity of halides meets the practical requirements of all-solid-state batteries. Furthermore, halide materials, predominantly covalently bonded with a soft lattice, exhibit good mechanical processability and film-forming properties, facilitating close contact with the positive and negative electrode interfaces and reducing interfacial impedance. More importantly, halide electrolytes generally possess a wide electrochemical window, with oxidation decomposition potentials typically exceeding 4.0 V, allowing direct matching with high-voltage cathodes (such as NCM and LNMO), simplifying interface engineering and improving battery energy output. In addition, halide materials are less sensitive to air and humidity, exhibiting superior stability compared to sulfides and greater environmental adaptability. Through doping, anion modulation, or heterostructure design, their structural stability and ion conductivity can be further optimized, improving interfacial compatibility and cycle stability. In summary, developing a halide oxide solid electrolyte that combines high ionic conductivity, a wide electrochemical window, excellent interfacial stability, and good processing performance can not only effectively address the key technical challenges currently facing all-solid-state lithium batteries, but also provide a solid material foundation for promoting the engineering application of high-energy-density and safe energy storage systems, demonstrating significant application value and broad industrial prospects. Summary of the Invention

[0004] The purpose of this invention is to at least solve one of the technical problems existing in the prior art, and to provide a halide oxide solid electrolyte, its preparation method and an all-solid-state battery.

[0005] The technical solution of the present invention is as follows: A first aspect of the present invention provides a halide oxide solid electrolyte, wherein the solid electrolyte is Li a M b N c X d O e Wherein, M and N are the same element or different elements, and M and N are at least one of Zn, Ba, Al, In, Y, Cr, Ti, Zr, Hf, Nb, Ta, La, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu; X is at least one of F, Cl, Br, and I; 0.3 <a≤3,0<b≤1,0<c≤1,0<d≤6,0<e≤3。

[0006] Preferably, the cation radius of M is greater than or equal to the cation radius of N, and the cation valence state of M is greater than or equal to the cation valence state of N.

[0007] Preferably, the raw materials for preparing the solid electrolyte include LiX and MX. y and N x O z , where y is 1~5, x is 1~2, and z is 1~5.

[0008] Preferably, MXy It is at least one of ZnX2, BaX2, AlX3, InX3, YX3, CrX3, TiX4, ZrX4, HfX4, NbX5, TaX5, LaX3, CeX3, NdX3, SmX3, EuX3, GdX3, TbX3, DyX3, HoX3, ErX3, TmX3, YbX3, and LuX3; N x O z It is at least one of ZnO, BaO, Al2O3, In2O3, Y2O3, Cr2O3, TiO2, ZrO2, HfO2, Nb2O5, Ta2O5, La2O3, Ce2O3, Nd2O3, Sm2O3, Eu2O3, Gd2O3, Tb2O3, Dy2O3, Ho2O3, Er2O3, Tm2O3, Yb2O3, and Lu2O3.

[0009] Preferably, the solid electrolyte comprises Li 2.4 ZnBa 0.8 Cl 4.4 O 0.8 Li 2.5 Hf 0.5 Y 0.5 Cl 4.5 O 0.75 Li 2.5 Hf 0.5 Al 0.5 Cl 4.5 O 0.75 Li 0.7 La 0.5 In 0.5 Cl 2.2 O 0.75 Li 2.5 Hf 0.5 Y 0.5 F 0.3 Cl 4.2 O 0.75 Li 0.9 Zr 0.8 Cr 0.3 Cl 3.2 Br 0.9 O 0.45 Li 0.8 Ta 0.7 Cr 0.3 Cl 3.5 I 0.8 O 0.2 LiTa 0.8 Zr 0.2 Cl 3.3 O 1.25 LiTa 0.8 Zr0.2 Cl5O 0.4 LiTa 0.5 Zr 0.5 Cl 3.7 O 0.9 LiNb 0.5 Zr 0.5 Cl 3.7 O 0.9 .

[0010] A second aspect of the present invention provides a method for preparing a halide oxide solid electrolyte, comprising: using high-valence metal oxides, halides and lithium halides as raw materials, and preparing a solid electrolyte by ball milling, cold pressing, hot pressing and / or heat treatment processes.

[0011] Preferably, LiX and MX are disposed of in an inert gas atmosphere. y and N x O z The mixture is thoroughly mixed to obtain a mixture; wherein M and N are the same element or different elements, and M and N are at least one of Zn, Ba, Al, In, Y, Cr, Ti, Zr, Hf, Nb, Ta, La, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu; X is at least one of F, Cl, Br and I, y is 1~5, x is 1~2 and z is 1~5; The mixture is first ball-milled at low speed, then ball-milled at high speed; The ball-milled mixture is first cold-pressed, and then heat-treated under vacuum to obtain electrolyte sheets; The electrolyte sheet is pulverized, cold-pressed again, and then hot-pressed to prepare a solid electrolyte.

[0012] Preferably, the conditions for low-speed ball milling include: a ball milling speed of 50 rpm to 150 rpm and a ball milling time of 10 min to 120 min; The conditions for high-speed ball milling include: adding ZrO2 grinding balls and milling them together with the raw materials, the mass ratio of ZrO2 grinding balls to raw materials being 5~200:1, the ball milling speed being 400rpm~700rpm, and the ball milling time being 0.5h~300h; The conditions for cold pressing include: cold pressing pressure of 200MPa~500MPa and cold pressing time of 0.1min~10min; The conditions for hot pressing include: hot pressing pressure of 200MPa~500MPa, hot pressing temperature of 80℃~180℃, and hot pressing time of 5min~120min. The heat treatment conditions include: a heat treatment temperature of 150℃ to 600℃ and a heat treatment time of 10 min to 800 min.

[0013] A third aspect of the present invention provides an all-solid-state battery, comprising the solid electrolyte described herein or the solid electrolyte obtained by the preparation method described herein.

[0014] Preferably, the all-solid-state battery further includes a positive electrode, a negative electrode, and a negative electrode interface layer; The positive electrode is prepared by grinding or low-speed ball milling of positive electrode active material and positive electrode filler. The positive electrode active material is at least one of LiCoO2, LiFePO4, NCM ternary material, lithium-rich phase lithium manganese oxide, lithiated layered oxide and lithiated layered sulfide. The positive electrode filler is at least one of conductive agent and ion-conducting agent made from the solid electrolyte. The conductive agent is at least one of graphite, carbon black, acetylene black, Ketjen black and carbon fiber. The negative electrode interface layer is at least one of sulfides, halides, and halide oxides.

[0015] This invention has at least one of the following beneficial effects: 1. This invention addresses the problems of low ionic conductivity and high cost in existing electrolyte technologies by providing a halogen oxide solid electrolyte Li that combines high ionic conductivity with cost advantages. a M b N c X d O e This invention provides a novel type of oxyhalide electrolyte with a room temperature ionic conductivity of up to 8 mS / cm. -1 This invention improves the ionic conductivity of the electrolyte; furthermore, the introduction of oxygen enhances the chemical stability of the electrolyte; at the same time, the components of this invention have great adjustability, significantly reducing raw material costs. It expands the family of oxyhalide electrolytes, and when applied to all-solid-state lithium metal batteries, it can exhibit good electrochemical performance. The preparation process is relatively simple, which is conducive to large-scale production.

[0016] 2. This invention differs from existing technologies that use lithium oxide or lithium hydroxide as an oxygen source to synthesize halide oxides. Instead, it selects high-valence metal oxides (such as ZnO, BaO, Al2O3, In2O3, Y2O3, Cr2O3, La2O3, Ce2O3, Nd2O3, Sm2O3, Eu2O3, Gd2O3, Tb2O3, Dy2O3, Ho2O3, Er2O3, Tm2O3, Yb2O3, Lu2O3, TiO2, ZrO2, HfO2, Nb2O5, and Ta2O5, etc.) and halides and lithium halides through ball milling combined with annealing and hot pressing processes to synthesize a series of halide oxide solid electrolytes with high ionic conductivity. The cost of the oxides used is much lower than that of halides of the same metal element, which greatly reduces the cost of raw materials. Furthermore, the introduction of oxygen enhances the chemical stability of the electrolyte. Attached Figure Description

[0017] Figure 1 This is the XRD of niobium-based chloride oxide prepared by ball milling in Example 1 of the present invention.

[0018] Figure 2 This is the XRD pattern of the tantalum-based oxide chloride solid electrolyte prepared by ball milling in Example 2 of this invention.

[0019] Figure 3 This is the impedance diagram of niobium-based chloride obtained in Example 1 of the present invention at room temperature.

[0020] Figure 4 This is the impedance diagram of tantalum-based chloride obtained in Example 2 of the present invention at room temperature.

[0021] Figure 5 This is a SEM image of niobium-based chloride obtained in Example 1 of the present invention.

[0022] Figure 6 This is a SEM image of niobium-based chlorine oxide after cold pressing into sheets, obtained in Example 1 of this invention.

[0023] Figure 7 This is a charge-discharge curve of a full battery using niobium-based chlorine oxide as a solid electrolyte, obtained in Example 1 of this invention.

[0024] Figure 8 This is a cycle stability curve of a full cell using niobium-based chlorine oxide as a solid electrolyte, obtained in Example 1 of this invention.

[0025] Figure 9 This is a rate performance diagram of a full cell using tantalum-based chlorine oxide as a solid electrolyte obtained in Example 2 of the present invention at low temperature.

[0026] Figure 10 This is a cycling stability diagram at low temperature of a full cell using tantalum-based chloride oxide as a solid electrolyte obtained in Example 2 of the present invention. Detailed Implementation

[0027] 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.

[0028] One embodiment of the present invention provides a halogen oxide solid electrolyte, wherein the solid electrolyte is Li a M b N c X d O eWherein, M and N are the same element or different elements, and M and N are at least one of Zn, Ba, Al, In, Y, Cr, Ti, Zr, Hf, Nb, Ta, La, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu; X is at least one of F, Cl, Br, and I; 0.3

[0029] This invention addresses the problems of low ionic conductivity and high cost in existing electrolyte technologies by providing a halogen oxide solid electrolyte, Li, that combines high ionic conductivity with cost advantages. a M b N c X d O e This invention provides a novel type of oxyhalide electrolyte with a room temperature ionic conductivity of up to 8 mS / cm. -1 This improves the ionic conductivity of the electrolyte; furthermore, the introduction of oxygen enhances the chemical stability of the electrolyte.

[0030] In some embodiments, the following may be preferred conditions: (1) X can preferably be Cl, Br, or I; (2) Cation radius: M≥N; (3) Cation valence state: M≥N.

[0031] In some embodiments, the following are preferred conditions for improving the high-voltage stability of the solid electrolyte: (1) X can be preferably F; (2) Cations such as In and Al are preferred.

[0032] In some embodiments, to improve the compatibility of the solid electrolyte with the LiIn anode, the following conditions may be preferred: (1) Hf-based halide oxides doped with Y and Al; (2) Y-based, Sm-based, Nd-based, and La-based halide oxide systems.

[0033] In some embodiments, the raw materials for preparing the solid electrolyte include LiX and MX. y and N x O z , where y is 1~5, x is 1~2, and z is 1~5.

[0034] In some embodiments, MX y ​It is at least one of ZnX2, BaX2, AlX3, InX3, YX3, CrX3, TiX4, ZrX4, HfX4, NbX5, TaX5, LaX3, CeX3, NdX3, SmX3, EuX3, GdX3, TbX3, DyX3, HoX3, ErX3, TmX3, YbX3, and LuX3; N x O z It is at least one of ZnO, BaO, Al2O3, In2O3, Y2O3, Cr2O3, TiO2, ZrO2, HfO2, Nb2O5, Ta2O5, La2O3, Ce2O3, Nd2O3, Sm2O3, Eu2O3, Gd2O3, Tb2O3, Dy2O3, Ho2O3, Er2O3, Tm2O3, Yb2O3, and Lu2O3.

[0035] In some embodiments, the solid electrolyte includes Li 2.4 ZnBa 0.8 Cl 4.4 O 0.8 Li 2.5 Hf 0.5 Y 0.5 Cl 4.5 O 0.75 Li 2.5 Hf 0.5 Al 0.5 Cl 4.5 O 0.75 Li 0.7 La 0.5 In 0.5 Cl 2.2 O 0.75 Li 2.5 Hf 0.5 Y 0.5 F 0.3 Cl 4.2 O 0.75 Li 0.9 Zr 0.8 Cr 0.3 Cl 3.2 Br 0.9 O 0.45 Li 0.8 Ta 0.7 Cr 0.3 Cl 3.5 I 0.8 O 0.2 LiTa 0.8 Zr 0.2 Cl 3.3 O 1.25 LiTa 0.8 Zr 0.2Cl5O 0.4 LiTa 0.5 Zr 0.5 Cl 3.7 O 0.9 LiNb 0.5 Zr 0.5 Cl 3.7 O 0.9 .

[0036] Another embodiment of the present invention provides a method for preparing a halide oxide solid electrolyte, comprising: using high-valence metal oxides, halides and lithium halides as raw materials, and preparing a solid electrolyte by ball milling, cold pressing, hot pressing and / or heat treatment processes.

[0037] This invention uses high-valence metal oxides, halides, and lithium halides to synthesize a series of high-ionic-conductivity halide solid electrolytes through ball milling combined with annealing and hot pressing processes. The cost of the oxides used is much lower than that of halides of the same metal element, which greatly reduces the cost of raw materials.

[0038] In some embodiments, LiX and MX are used in an inert gas atmosphere. y and N x O z The mixture is thoroughly mixed to obtain a mixture; wherein M and N are the same element or different elements, and M and N are at least one of Zn, Ba, Al, In, Y, Cr, Ti, Zr, Hf, Nb, Ta, La, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu; X is at least one of F, Cl, Br and I, y is 1~5, x is 1~2 and z is 1~5; The mixture is first ball-milled at low speed, then ball-milled at high speed; The ball-milled mixture is first cold-pressed, and then heat-treated under vacuum to obtain electrolyte sheets; The electrolyte sheet is pulverized, cold-pressed again, and then hot-pressed to prepare a solid electrolyte.

[0039] In some embodiments, the conditions for low-speed ball milling include: a ball milling speed of 50 rpm to 150 rpm and a ball milling time of 10 min to 120 min; preferably, a ball milling speed of 80 rpm to 120 rpm and a ball milling time of 30 min to 120 min; more preferably, a ball milling speed of 100 rpm and a ball milling time of 60 min to 120 min. The conditions for high-speed ball milling include: adding ZrO2 grinding balls and milling them together with the raw material, with a ZrO2 grinding ball to raw material mass ratio of 5~200:1, a ball milling speed of 400rpm~700rpm, and a ball milling time of 0.5h~300h; preferably, the ZrO2 grinding ball to raw material mass ratio is 20~200:1, the ball milling speed is 400rpm~600rpm, and the ball milling time is 3h~30h; more preferably, the ZrO2 grinding ball to raw material mass ratio is 20~50:1, the ball milling speed is 500rpm~600rpm, and the ball milling time is 10h~30h. The cold pressing conditions include: a cold pressing pressure of 200 MPa to 500 MPa and a cold pressing time of 0.1 min to 10 min; preferably, a cold pressing pressure of 300 MPa to 500 MPa and a cold pressing time of 2 min to 10 min; more preferably, a cold pressing pressure of 300 MPa to 400 MPa and a cold pressing time of 5 min to 10 min. The hot pressing conditions include: a hot pressing pressure of 200 MPa to 500 MPa, a hot pressing temperature of 80°C to 180°C, and a hot pressing time of 5 min to 120 min; preferably, a hot pressing pressure of 300 MPa to 500 MPa, a hot pressing temperature of 100°C to 180°C, and a hot pressing time of 10 min to 100 min; more preferably, a hot pressing pressure of 300 MPa to 400 MPa, a hot pressing temperature of 120°C to 180°C, and a hot pressing time of 30 min to 80 min. The heat treatment conditions include: a heat treatment temperature of 150℃ to 600℃ and a heat treatment time of 10 min to 800 min. Preferably, the heat treatment temperature is 200℃ to 600℃ and the heat treatment time is 30 min to 800 min. More preferably, the heat treatment temperature is 300℃ to 600℃ and the heat treatment time is 10 min to 300 min.

[0040] Another embodiment of the present invention provides an all-solid-state battery, comprising the solid electrolyte or the solid electrolyte obtained by the preparation method described above.

[0041] This invention uses Li a M b N c X d O e When applied to all-solid-state lithium metal batteries, it exhibits excellent electrochemical performance.

[0042] In some embodiments, the all-solid-state battery is assembled by pressing layers of lithium indium alloy as the negative electrode, sulfide or halide as the negative electrode interface layer, the halide oxide developed in this invention as the solid electrolyte, lithium transition metal oxide, such as LiCoO2, and ternary materials as the positive electrode, and assembling the all-solid-state battery by pressing layers under a certain pressure.

[0043] In some embodiments, the positive electrode side is obtained by grinding or low-speed ball milling of positive electrode active material and positive electrode filler. The positive electrode active material includes, but is not limited to, at least one of LiCoO2, LiFePO4, NCM ternary materials, lithium-rich phase lithium manganese oxide and lithiated layered oxides, and lithiated layered sulfides. The positive electrode filler is at least one of the prepared halide oxide ion-conducting agent and conductive agent; the preparation method of the ion-conducting agent includes: mixing the positive electrode material and the positive electrode filler (at least one of halide oxide and conductive agent) and grinding them thoroughly, grinding in a mortar for 10-30 min, or ball milling (100-200 rpm for 30-60 min); the solid electrolyte between the ion-conducting agent and the positive and negative electrodes of the battery is the same material; the conductive agent may include at least one of graphite, carbon black, acetylene black, Ketjen black, and carbon fiber. The negative electrode is a LiIn alloy; the interface layer between the solid electrolyte and the negative electrode is Li6PS5Cl, Li 10 GeP2S 12 Li3YCl6, Li 6-4x-3y Hf x Y y Cl6 (0.3≤x≤0.7, 0.3≤y≤0.7) and Li 6-4x- 3y Hf x Y y O a Cl 6-0.5a One of the following (0.3≤x≤0.7, 0.3≤y≤0.7, 0.45≤a≤1.0). Where Li 6-4x- 3y Hf x Y y Cl6 (raw materials are stoichiometric LiCl, HfCl4, and YCl3) and Li 6-4x-3y Hf x Y y O a Cl 6-0.5a The raw materials (LiCl, HfCl4, and Y2O3 in stoichiometric ratio) were synthesized by ball milling at 400 rpm to 600 rpm for 5 to 20 hours.

[0044] 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.

[0045] Example 1 This embodiment prepares a chlorine oxide, LiNbCl, which combines high ionic conductivity and cost advantages. 3.25 O 1.375 The specific preparation steps for solid-state electrolytes and their application in all-solid-state lithium metal batteries are as follows: (1) Preparation of raw materials: Lithium chloride, niobium chloride, and niobium pentoxide (Nb2O5) powder were prepared according to a stoichiometric ratio of 1:0.45:0.275 for the synthesis of LiNbCl. 3.25 O 1.375 The purity of the above substances is greater than 99.9%. They are thoroughly mixed in a mortar or mixed at low speed in a ball mill jar filled with argon gas. The ball milling speed is 150 rpm and the running time is 30 min.

[0046] (2) High-energy ball milling: The uniformly mixed raw materials are placed in a ball milling jar and mixed according to the mass ratio of ZrO2 ball milling beads to raw materials of 40:1; the ball milling time is 20h; the ball milling speed is 600rpm; the ionic conductivity test conditions are cold pressing at 300MPa and testing under the pressure.

[0047] (3) Hot pressing: The ball-milled sample is cold-pressed into a sheet, and heat-treated at 180°C for 30 min under a pressure of 300 MPa. The ionic conductivity is then tested while maintaining the pressure.

[0048] (4) All-solid-state battery assembly: All steps were carried out in a glove box filled with argon (H2O<0.1ppm, O2<0.1ppm). First, positive electrode active material NCM83 and halide oxide LiNbCl were weighed in a mass ratio of 70:25:5. 3.25 O 1.375 The positive electrode composite material was obtained by grinding the conductive agent VGCF in a mortar for 30 minutes. Then, 60 mg of chlorine oxide LiNbCl was weighed out. 3.25 O 1.375 50 mg of Li6PS5Cl and 80 mg of the positive electrode composite were cold-pressed layer by layer into sheets under a pressure of 300 MPa. A lithium-indium alloy was used as the negative electrode, with a lithium to indium mass ratio of 1:30, and the sheets were assembled into an all-solid-state battery under a pressure of 100 MPa.

[0049] (5) Performance testing: Using the Neware battery testing system at 30°C at 3-4.3 V (vs. Li / Li) + The electrochemical performance was evaluated within the voltage range and at various current densities.

[0050] The XRD pattern of the niobium-based chlorine oxide prepared in Example 1 is as follows: Figure 1 As shown.

[0051] The impedance diagram of the niobium-based chloride prepared in Example 1 at room temperature is shown below. Figure 3 As shown, this demonstrates that the synthesized niobium-based chloride oxides have high ionic conductivity.

[0052] SEM image of the niobium-based chlorine oxide prepared in Example 1 is shown below. Figure 5As shown, the SEM image of niobium-based chloride oxide after cold pressing is as follows: Figure 6 As shown, this illustrates the dense cracks in the niobium-based chlorine oxide electrolyte after cold pressing.

[0053] The charge-discharge curves of the full battery prepared in Example 1 using niobium-based chlorine oxide as the solid electrolyte are shown in the figure below. Figure 7 As shown, this demonstrates that the full cell has a specific capacity of up to 210 mAh / g and an initial coulombic efficiency of 86.7% at 0.2C.

[0054] The cycle stability curve of the full cell prepared in Example 1 using niobium-based chlorine oxide as the solid electrolyte is shown in the figure below. Figure 8 As shown, this demonstrates that the battery has a specific capacity exceeding 180 mAh / g at 2C and a capacity retention rate exceeding 97% after 300 cycles.

[0055] Example 2 This embodiment prepares a chlorine oxide, LiTaCl, which combines high ionic conductivity and cost advantages. 3.25 O 1.375 The solid electrolyte, and its application in all-solid-state lithium metal batteries, are prepared using the following specific steps: (1) Preparation of raw materials: Weigh the raw material powders of lithium chloride, tantalum chloride, and tantalum oxide according to the stoichiometric ratio of 1:0.45:0.275 for the synthesis of LiTaCl. 3.25 O 1.375 The purity of the above substances is greater than 99.99%. They are thoroughly mixed in a mortar or mixed at low speed in a ball mill jar filled with argon gas. The ball milling speed is 150 rpm and the running time is 30 min.

[0056] (2) High-energy ball milling: The uniformly mixed raw materials are placed in a ball milling jar and mixed according to the mass ratio of ZrO2 ball milling beads to raw materials of 40:1; the ball milling time is 20h; the ball milling speed is 600rpm; the ionic conductivity test conditions are cold pressing at 300MPa and testing under the pressure.

[0057] (3) Hot pressing: The ball-milled sample is cold-pressed into a sheet, and heat-treated at 180°C for 30 min under a pressure of 300 MPa. The ionic conductivity is then tested while maintaining the pressure.

[0058] (4) All-solid-state battery assembly: All steps were carried out in a glove box filled with argon (H2O<0.1ppm, O2<0.1ppm). First, the positive electrode active material NCM83 and the halide oxide LiTaCl were weighed in a mass ratio of 70:25:5. 3.25 O 1.375The positive electrode composite material was obtained by grinding the conductive agent VGCF in a mortar for 30 minutes. Then, 60 mg of chlorine oxide LiTaCl was weighed out sequentially. 3.25 O 1.375 50 mg of Li₆PS₅Cl and 80 mg of the positive electrode composite were cold-pressed layer by layer into sheets under a pressure of 300 MPa. A lithium-indium alloy was used as the negative electrode, with a lithium to indium mass ratio of 1:30, and the sheets were assembled into an all-solid-state battery under a pressure of 100 MPa.

[0059] (5) Performance testing: Using the Neware battery testing system at -20°C at 3-4.3 V (vs. Li / Li) + The electrochemical performance was evaluated within the voltage range and at various current densities.

[0060] The XRD pattern of the tantalum-based oxide chloride solid electrolyte prepared in Example 2 is shown below. Figure 2 As shown.

[0061] The impedance diagram of the tantalum-based chloride oxide prepared in Example 2 at room temperature is shown below. Figure 4 As shown, this demonstrates that the synthesized tantalum-based chloride oxide has high ionic conductivity.

[0062] The rate performance at low temperature of the full cell prepared in Example 2 using tantalum-based oxide chloride as the solid electrolyte is as follows: Figure 9 As shown, this demonstrates that the battery can operate normally at -20℃ and has good rate performance.

[0063] The cycling stability diagram of the full cell prepared in Example 2 using tantalum-based oxychloride as the solid electrolyte at low temperature is shown in the figure below. Figure 10 As shown, this demonstrates that the battery can achieve a specific capacity of 102 mAh / g when operating at a 2C rate at -20℃, and retains more than 99% of its capacity after 300 cycles.

[0064] Example 3 This embodiment prepares a chlorine oxide Li that combines high ionic conductivity and cost advantages. 2.4 ZnBa 0.8 Cl 4.4 O 0.8 The solid electrolyte, and its application in all-solid-state lithium metal batteries, are prepared using the following specific steps: (1) Preparation of raw materials: Weigh the raw material powders lithium chloride, zinc chloride, and barium oxide according to the stoichiometric ratio of 2.4:1:0.8 for the synthesis of Li. 2.4 ZnBa 0.8 Cl 4.4 O 0.8The purity of the above substances is greater than 99.99%. They are thoroughly mixed in a mortar or mixed at low speed in a ball mill jar filled with argon gas. The ball milling speed is 150 rpm and the running time is 30 min.

[0065] (2) High-energy ball milling: Place the uniformly mixed raw material in a ball milling jar and mix it according to the mass ratio of ZrO2 ball milling beads to raw material of 40:1; the ball milling time is 20h; the ball milling speed is 500rpm; the ionic conductivity test conditions are cold pressing at 300MPa and testing under the pressure.

[0066] (3) Heat treatment: The ball-milled sample was cold-pressed into a sheet, transferred into a quartz tube and vacuum-sealed, and heated at 300℃ for 1 hour. The cooled sample was ground into powder in a mortar, and the sample was cold-pressed again at 300MPa. The ionic conductivity was tested while maintaining the pressure.

[0067] (4) Hot pressing: The ball-milled sample is cold-pressed into a sheet, and heat-treated at 180°C for 30 min under a pressure of 300 MPa. The ionic conductivity is then tested while maintaining the pressure.

[0068] (5) All-solid-state battery assembly: All steps were carried out in a glove box filled with argon (H2O<0.1ppm, O2<0.1ppm). First, the positive electrode active material NCM83 and the halide oxide Li were weighed in a mass ratio of 70:25:5. 2.4 ZnBa 0.8 Cl 4.4 O 0.8 The positive electrode composite material was obtained by grinding the conductive agent VGCF in a mortar for 30 minutes. Then, 60 mg of chlorine oxide Li was weighed out. 2.4 ZnBa 0.8 Cl 4.4 O 0.8 50 mg of Li6PS5Cl and 80 mg of the positive electrode composite were cold-pressed layer by layer into sheets under a pressure of 300 MPa. A lithium-indium alloy was used as the negative electrode, with a lithium to indium mass ratio of 1:30, and the cells were assembled into an all-solid-state battery under a pressure of 100 MPa.

[0069] (6) Performance testing: Using the Neware battery testing system at 30°C, at 3-4.3 V (vs. Li / Li) + The electrochemical performance was evaluated within the voltage range and at various current densities.

[0070] Example 4 This embodiment prepares a chlorine oxide Li that combines high ionic conductivity and cost advantages. 2.5 Hf 0.5 Y 0.5 Cl 4.5 O0.75 The specific preparation steps for solid-state electrolytes and their application in all-solid-state lithium metal batteries are as follows: (1) Preparation of raw materials: Weigh the raw material powders of lithium chloride, hafnium chloride, and yttrium oxide according to the stoichiometric ratio of 2.5:0.5:0.25 for the synthesis of Li. 2.5 Hf 0.5 Y 0.5 Cl 4.5 O 0.75 The purity of the above substances is greater than 99.99%. They are thoroughly mixed in a mortar or mixed at low speed in a ball mill jar filled with argon gas. The ball milling speed is 150 rpm and the running time is 30 min.

[0071] (2) High-energy ball milling: The uniformly mixed raw materials are placed in a ball milling jar and mixed according to the mass ratio of ZrO2 ball milling beads to raw materials of 40:1; the ball milling time is 20h; the ball milling speed is 600rpm; the ionic conductivity test conditions are cold pressing at 300MPa and testing under the pressure.

[0072] (3) Heat treatment: The ball-milled sample was cold-pressed into a sheet, transferred into a quartz tube and vacuum-sealed, and heated at 300℃ for 1 hour. The cooled sample was ground into powder in a mortar, and the sample was cold-pressed again at 300MPa. The ionic conductivity was tested while maintaining the pressure.

[0073] (4) All-solid-state battery assembly: All steps were carried out in a glove box filled with argon (H2O<0.1ppm, O2<0.1ppm). First, the positive electrode active material NCM83 and the halide oxide Li were weighed in a mass ratio of 70:25:5. 2.5 Hf 0.5 Y 0.5 Cl 4.5 O 0.75 The positive electrode composite material was obtained by grinding the conductive agent VGCF in a mortar for 30 minutes. Then, 60 mg of chlorine oxide Li was weighed out. 2.5 Hf 0.5 Y 0.5 Cl 4.5 O 0.75 80 mg of the positive electrode composite was cold-pressed layer by layer into sheets under a pressure of 300 MPa. Using a lithium-indium alloy as the negative electrode, with a lithium to indium mass ratio of 1:30, an all-solid-state battery was assembled under a pressure of 100 MPa.

[0074] (5) Performance testing: Using the Neware battery testing system at 30°C at 3-4.3 V (vs. Li / Li) + The electrochemical performance was evaluated within the voltage range and at various current densities.

[0075] Example 5 This embodiment prepares a chlorine oxide Li that combines high ionic conductivity and cost advantages. 2.5 Hf 0.5 Al 0.5 Cl 4.5 O 0.75 The specific preparation steps for solid-state electrolytes and their application in all-solid-state lithium metal batteries are as follows: (1) Preparation of raw materials: Weigh the raw material powders of lithium chloride, hafnium chloride, and aluminum oxide according to the stoichiometric ratio of 2.5:0.5:0.25 for the synthesis of Li. 2.5 Hf 0.5 Al 0.5 Cl 4.5 O 0.75 The purity of the above substances is greater than 99.99%. They are thoroughly mixed in a mortar or mixed at low speed in a ball mill jar filled with argon gas. The ball milling speed is 150 rpm and the running time is 30 min.

[0076] (2) High-energy ball milling: The uniformly mixed raw materials are placed in a ball milling jar and mixed according to the ratio of ZrO2 ball milling beads to raw materials of 40:1; the ball milling time is 20h; the ball milling speed is 600rpm; the ionic conductivity test conditions are cold pressing at 300MPa and testing under the pressure.

[0077] (3) Heat treatment: The ball-milled sample was cold-pressed into a sheet, transferred into a quartz tube and vacuum-sealed, and heated at 300℃ for 1 hour. The cooled sample was ground into powder in a mortar, and the sample was cold-pressed again at 300MPa. The ionic conductivity was tested while maintaining the pressure.

[0078] (4) All-solid-state battery assembly: All steps were carried out in a glove box filled with argon (H2O<0.1ppm, O2<0.1ppm). First, the positive electrode active material NCM83 and the halide oxide Li were weighed in a mass ratio of 70:25:5. 2.5 Hf 0.5 Al 0.5 Cl 4.5 O 0.75 The positive electrode composite material was obtained by grinding the conductive agent VGCF in a mortar for 30 minutes. Then, 60 mg of chlorine oxide Li was weighed out. 2.5 Hf 0.5 Al 0.5 Cl 4.5 O 0.75 80 mg of the positive electrode composite was cold-pressed layer by layer into sheets under a pressure of 300 MPa. A lithium-indium alloy was used as the negative electrode, with a lithium to indium mass ratio of 1:30, and the cells were assembled into an all-solid-state battery under a pressure of 100 MPa.

[0079] (5) Performance testing: Using the Neware battery testing system at 30°C at 3-4.5 V (vs. Li / Li) + The electrochemical performance was evaluated within the voltage range and at various current densities.

[0080] Example 6 This embodiment prepares a chlorine oxide Li that combines high ionic conductivity and cost advantages. 0.7 La 0.5 In 0.5 Cl 2.2 O 0.75 The specific preparation steps for solid-state electrolytes and their application in all-solid-state lithium metal batteries are as follows: (1) Preparation of raw materials: Weigh the raw material powders of lithium chloride, lanthanum chloride, and indium oxide according to the stoichiometric ratio of 0.7:0.5:0.25 for the synthesis of Li. 0.7 La 0.5 In 0.5 Cl 2.2 O 0.75 The purity of the above substances is greater than 99.99%. They are thoroughly mixed in a mortar or mixed at low speed in a ball mill jar filled with argon gas. The ball milling speed is 150 rpm and the running time is 30 min.

[0081] (2) High-energy ball milling: Place the uniformly mixed raw material 1 in a ball milling jar and mix it according to the ratio of ZrO2 ball milling beads to raw material of 40:1; the ball milling time is 20h; the ball milling speed is 400rpm; the ionic conductivity test conditions are cold pressing at 300MPa and testing under the pressure.

[0082] (3) Heat treatment: The ball-milled sample was cold-pressed into a sheet, transferred into a quartz tube and vacuum-sealed, and heated at 300℃ for 1 hour. The cooled sample was ground into powder in a mortar, and the sample was cold-pressed again at 300MPa. The ionic conductivity was tested while maintaining the pressure.

[0083] (4) Hot pressing: The ball-milled sample is cold-pressed into a sheet, and heat-treated at 180°C for 30 min under a pressure of 300 MPa. The ionic conductivity is then tested while maintaining the pressure.

[0084] (5) All-solid-state battery assembly: All steps were carried out in an argon-filled glove box (H2O<0.1ppm, O2<0.1ppm). First, the positive electrode active material NCM83 and the halide oxide Li were weighed in a mass ratio of 70:25:5. 0.7 La 0.5 In 0.5 Cl 2.2 O 0.75The positive electrode composite material was obtained by grinding the conductive agent VGCF in a mortar for 30 minutes. Then, 60 mg of chlorine oxide Li was weighed out. 0.7 La 0.5 In 0.5 Cl 2.2 O 0.75 50 mg of Li₆PS₅Cl and 80 mg of the positive electrode composite were cold-pressed layer by layer into sheets under a pressure of 300 MPa. A lithium-indium alloy was used as the negative electrode, with a lithium to indium mass ratio of 1:30, and the sheets were assembled into an all-solid-state battery under a pressure of 100 MPa.

[0085] (6) Performance testing: Using the Neware battery testing system at 30°C at 3-4.7 V (vs. Li / Li) + The electrochemical performance was evaluated within the voltage range and at various current densities.

[0086] Example 7 This embodiment prepares a fluorochloride Li with both high ionic conductivity and cost advantages. 2.5 Hf 0.5 Y 0.5 F 0.3 Cl 4.2 O 0.75 The specific preparation steps for solid-state electrolytes and their application in all-solid-state lithium metal batteries are as follows: (2) Preparation of raw materials: Weigh the raw material powders of lithium fluoride, lithium chloride, hafnium chloride, and yttrium oxide according to the stoichiometric ratio of 0.3:2.2:0.5:0.25 for the synthesis of Li. 2.5 Hf 0.5 Y 0.5 F 0.3 Cl 4.2 O 0.75 The purity of the above substances is greater than 99.99%. They are thoroughly mixed in a mortar or mixed at low speed in a ball mill jar filled with argon gas. The ball milling speed is 150 rpm and the running time is 30 min.

[0087] (2) High-energy ball milling: The uniformly mixed raw materials are placed in a ball milling jar and mixed according to the mass ratio of ZrO2 ball milling beads to raw materials of 40:1; the ball milling time is 20h; the ball milling speed is 600rpm; the ionic conductivity test conditions are cold pressing at 300MPa and testing under the pressure.

[0088] (3) Heat treatment: The ball-milled sample was cold-pressed into a sheet, transferred into a quartz tube and vacuum-sealed, and heated at 300℃ for 1 hour. The cooled sample was ground into powder in a mortar, and the sample was cold-pressed again at 300MPa. The ionic conductivity was tested while maintaining the pressure.

[0089] (4) All-solid-state battery assembly: All steps were carried out in a glove box filled with argon (H2O<0.1ppm, O2<0.1ppm). First, the positive electrode active material NCM83 and the halide oxide Li were weighed in a mass ratio of 70:25:5. 2.5 Hf 0.5 Y 0.5 F 0.3 Cl 4.2 O 0.75 The positive electrode composite material was obtained by grinding the conductive agent VGCF in a mortar for 30 minutes. Then, 60 mg of chlorine oxide Li was weighed out. 2.5 Hf 0.5 Y 0.5 F 0.3 Cl 4.2 O 0.75 80 mg of the positive electrode composite was cold-pressed layer by layer into sheets under a pressure of 300 MPa. Using a lithium-indium alloy as the negative electrode, with a lithium to indium mass ratio of 1:30, an all-solid-state battery was assembled under a pressure of 100 MPa.

[0090] (5) Performance testing: Using the Neware battery testing system at 30°C, the battery was tested at 3-4.9 V (vs. Li / Li). + The electrochemical performance was evaluated within the voltage range and at various current densities.

[0091] Example 8 This embodiment prepares a chlorobromooxide Li₂ with both high ionic conductivity and cost advantages. 0.9 Zr 0.8 Cr 0.3 Cl 3.2 Br 0.9 O 0.45 The specific preparation steps for solid-state electrolytes and their application in all-solid-state lithium metal batteries are as follows: (1) Preparation of raw materials: Weigh the raw material powders lithium bromide, zirconium chloride, and chromium oxide in a stoichiometric ratio of 0.9:0.8:0.15 for the synthesis of Li. 0.9 Zr 0.8 Cr 0.3 Cl 3.2 Br 0.9 O 0.45 The purity of the above substances is greater than 99.99%. They are thoroughly mixed in a mortar or mixed at low speed in a ball mill jar filled with argon gas. The ball milling speed is 150 rpm and the running time is 30 min.

[0092] (2) High-energy ball milling: The uniformly mixed raw materials are placed in a ball milling jar and mixed according to the ratio of ZrO2 ball milling beads to raw materials of 40:1; the ball milling time is 16h; the ball milling speed is 500rpm; the ionic conductivity test conditions are cold pressing at 300MPa and testing under the pressure.

[0093] (3) Heat treatment: The ball-milled sample was cold-pressed into a sheet, transferred into a quartz tube and vacuum-sealed, and heated at 300℃ for 1 hour. The cooled sample was ground into powder in a mortar, and the sample was cold-pressed again at 300MPa. The ionic conductivity was tested while maintaining the pressure.

[0094] (4) Hot pressing: The ball-milled sample is cold-pressed into a sheet, and heat-treated at 180°C for 5 min to 120 min while maintaining a pressure of 300 MPa. The ionic conductivity is then tested while maintaining the pressure.

[0095] (5) All-solid-state battery assembly: All steps were carried out in an argon-filled glove box (H2O<0.1ppm, O2<0.1ppm). First, the positive electrode active material NCM83 and the halide oxide Li were weighed in a mass ratio of 70:25:5. 0.9 Zr 0.8 Cr 0.3 Cl 3.2 Br 0.9 O 0.45 The positive electrode composite material was obtained by grinding the conductive agent VGCF in a mortar for 30 min. Then, 60 mg of chlorine oxide, 50 mg of Li6PS5Cl, and 80 mg of the positive electrode composite were weighed sequentially and cold-pressed layer by layer into sheets under a pressure of 300 MPa. Using a lithium-indium alloy as the negative electrode, with a lithium to indium mass ratio of 1:30, an all-solid-state battery was assembled under a pressure of 100 MPa.

[0096] (6) Performance testing: Using the Neware battery testing system at 30°C, at 3-4.1 V (vs. Li / Li) + The electrochemical performance was evaluated within the voltage range and at various current densities.

[0097] Example 9 This embodiment prepares a chloriodide oxide Li that combines high ionic conductivity and cost advantages. 0.8 Ta 0.7 Cr 0.3 Cl 3.5 I 0.8 O 0.2 The solid electrolyte, and its application in all-solid-state lithium metal batteries, are prepared using the following specific steps: (1) Preparation of raw materials: Weigh lithium iodide, tantalum chloride, and chromium oxide powders in a stoichiometric ratio of 0.8:0.7:0.15 for the synthesis of Li. 0.8 Ta 0.7 Cr 0.3 Cl 3.5 I 0.8 O 0.2 The purity of the above substances is greater than 99.99%. They are thoroughly mixed in a mortar or mixed at low speed in a ball mill jar filled with argon gas. The ball milling speed is 150 rpm and the running time is 30 min.

[0098] (2) High-energy ball milling: Place the uniformly mixed raw material in a ball milling jar and mix according to the ratio of ZrO2 ball milling beads to raw material of 40:1; the ball milling time is 25h; the ball milling speed is 600rpm; the ionic conductivity test conditions are cold pressing at 300MPa and testing under the pressure.

[0099] (3) Heat treatment: After ball milling, the sample is cold-pressed into a sheet, transferred into a quartz tube and vacuum-sealed, and heated at 300℃ for 1 hour. After cooling, the sample is ground into powder in a mortar, and then cold-pressed again at 200MPa~500MPa. The ionic conductivity is tested while maintaining the pressure.

[0100] (4) Hot pressing: The ball-milled sample is cold-pressed into a sheet, and heat-treated at 180°C for 30 min under a pressure of 300 MPa. The ionic conductivity is then tested while maintaining the pressure.

[0101] (5) All-solid-state battery assembly: All steps were carried out in a glove box filled with argon (H2O<0.1ppm, O2<0.1ppm). First, the positive electrode active material NCM83 and the halide oxide Li were weighed in a mass ratio of 70:25:5. 0.8 Ta 0.7 Cr 0.3 Cl 3.5 I 0.8 O 0.2 The positive electrode composite material was obtained by grinding the conductive agent VGCF in a mortar for 30 minutes. Then, 60 mg of chlorine oxide Li was weighed out. 0.8 Ta 0.7 Cr 0.3 Cl 3.5 I 0.8 O 0.2 50 mg of Li6PS5Cl and 80 mg of the positive electrode composite were cold-pressed layer by layer into sheets under a pressure of 300 MPa. A lithium-indium alloy was used as the negative electrode, with a lithium to indium mass ratio of 1:30, and the sheets were assembled into an all-solid-state battery under a pressure of 100 MPa.

[0102] (6 Performance Testing: Using the Neware battery testing system at 30°C at 3-4.0 V (vs. Li / Li)) + The electrochemical performance was evaluated within the voltage range and at various current densities.

[0103] Example 10 This comparative example is a zirconium-doped lithium tantalum chloride oxychloride (LiTa). 0.8 Zr 0.2 Cl 3.3 O 1.25 Solid electrolyte and its synthesis method: The zirconium source used is ZrCl4. The specific preparation steps are similar to those in Example 2, except that the raw materials used are lithium chloride, tantalum chloride, zirconium chloride, and tantalum oxide in a stoichiometric ratio of 1:0.3:0.2:0.25 to synthesize LiTa. 0.8 Zr 0.2 Cl 3.3 O 1.25 .

[0104] Example 11 This comparative example is a zirconium-doped lithium tantalum chloride oxychloride (LiTa). 0.8 Zr 0.2 Cl5O 0.4 Solid electrolyte and its synthesis method: The zirconium source used is ZrO2. The specific preparation steps are similar to those in Example 2, except that the raw materials used are lithium chloride, tantalum chloride, zirconium oxide, and tantalum oxide in a stoichiometric ratio of 1:0.6:0.2:0.1 to synthesize LiTa. 0.8 Zr 0.2 Cl4O 0.9 .

[0105] Example 12 This comparative example is a zirconium-doped lithium tantalum chloride oxychloride (LiTa). 0.5 Zr 0.5 Cl 3.7 O 0.9 Solid electrolyte and its synthesis method: The zirconium sources used are ZrCl4 and ZrO2. The specific preparation steps are similar to those in Example 2, except that the raw materials used are lithium chloride, tantalum chloride, zirconium chloride, tantalum oxide, and zirconium oxide in a stoichiometric ratio of 1:0.3:0.3:0.1:0.2, to synthesize LiTa. 0.5 Zr 0.5 Cl 3.7 O 0.9 .

[0106] Example 13 This comparative example is a zirconium-doped lithium niobium chloride oxychloride (LiNb) 0.5 Zr 0.5 Cl 3.7 O 0.9Solid electrolyte and its synthesis method: The zirconium sources used are ZrCl4 and ZrO2. The specific preparation steps are similar to those in Example 1, except that the raw materials used are lithium chloride, niobium chloride, zirconium chloride, zirconium oxide, and niobium oxide in a stoichiometric ratio of 1:0.3:0.3:0.1:0.2 to synthesize LiNb. 0.5 Zr 0.5 Cl 3.7 O 0.9 .

[0107] The conductivity and high-voltage stability test results of the solid electrolytes prepared in Examples 1-13 are shown in Table 1.

[0108] Table 1 As can be seen from Table 1, the above embodiments of the present invention provide a halide oxide solid electrolyte that has both high ionic conductivity and cost advantages. The ionic conductivity at room temperature can reach 8 mS / cm, and the process is simple and the cost is low, which is conducive to the realization of large-scale production and application.

[0109] Furthermore, comparing the above-described Examples 10-13 with Examples 1-2, it can be seen that the ionic conductivity of Examples 1-2 is much greater than that of Examples 10-13. This is because Zr was additionally introduced in Examples 10-13 compared to Examples 1-2. It can be seen that, compared to using a single Ta and Nb halide oxide with a large ionic radius and high valence, the introduction of Zr into the Ta and Nb halide oxides with a large ionic radius and high valence respectively results in a significant decrease in ionic conductivity. Therefore, using a single Ta and Nb halide oxide with a large ionic radius and high valence has a higher ionic conductivity.

[0110] 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 oxide solid electrolyte, characterized in that, The solid electrolyte is Li a M b N c X d O e Wherein, M and N are the same element or different elements, and M and N are at least one of Zn, Ba, Al, In, Y, Cr, Ti, Zr, Hf, Nb, Ta, La, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu; X is at least one of F, Cl, Br, and I; 0.3 <a≤3,0<b≤1,0<c≤1,0<d≤6,0<e≤3。 2. The halide oxide solid electrolyte according to claim 1, characterized in that, The cation radius of M is greater than or equal to the cation radius of N, and the cation valence state of M is greater than or equal to the cation valence state of N.

3. The halide oxide solid electrolyte according to claim 1, characterized in that, The raw materials for preparing the solid electrolyte include LiX and MX. y and N x O z , where y is 1~5, x is 1~2, and z is 1~5.

4. The halide oxide solid electrolyte according to claim 3, characterized in that, MX y It is at least one of ZnX2, BaX2, AlX3, InX3, YX3, CrX3, TiX4, ZrX4, HfX4, NbX5, TaX5, LaX3, CeX3, NdX3, SmX3, EuX3, GdX3, TbX3, DyX3, HoX3, ErX3, TmX3, YbX3, and LuX3; N x O z It is at least one of ZnO, BaO, Al2O3, In2O3, Y2O3, Cr2O3, TiO2, ZrO2, HfO2, Nb2O5, Ta2O5, La2O3, Ce2O3, Nd2O3, Sm2O3, Eu2O3, Gd2O3, Tb2O3, Dy2O3, Ho2O3, Er2O3, Tm2O3, Yb2O3, and Lu2O3.

5. The halide oxide solid electrolyte according to claim 1, characterized in that, LiNbCl is included 3.25 The 1.375 、LiTaCl 3.25 The 1.375 、Li 2.4 ZnBa 0.8 Cl 4.4 The 0.8 、Li 2.5 Hf 0.5 Y 0.5 Cl 4.5 The 0.75 、Li 2.5 Hf 0.5 Al 0.5 Cl 4.5 The 0.75 、Li 0.7 The 0.5 In 0.5 Cl 2.2 The 0.75 、Li 2.5 Hf 0.5 Y 0.5 F 0.3 Cl 4.2 The 0.75 、Li 0.9 Zr 0.8 Cr 0.3 Cl 3.2 Br 0.9 The 0.45 、Li 0.8 The 0.7 Cr 0.3 Cl 3.5 I 0.8 The 0.2 、LiTa 0.8 Zr 0.2 Cl 3.3 The 1.25 、LiTa 0.8 Zr 0.2 Cl5O 0.4 、LiTa 0.5 Zr 0.5 Cl 3.7 The 0.9 、LiNb 0.5 Zr 0.5 Cl 3.7 The 0.9 。 6. The method for preparing the solid electrolyte according to any one of claims 1 to 5, characterized in that, Includes the following steps: Solid electrolytes are prepared from high-valence metal oxides, halides, and lithium halides through ball milling, cold pressing, hot pressing, and / or heat treatment processes.

7. The preparation method according to claim 6, characterized in that, The preparation method includes the following specific steps: In an inert gas atmosphere, LiX and MX y and N x O z The mixture is thoroughly mixed to obtain a mixture; wherein M and N are the same element or different elements, and M and N are at least one of Zn, Ba, Al, In, Y, Cr, Ti, Zr, Hf, Nb, Ta, La, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu; X is at least one of F, Cl, Br and I, y is 1~5, x is 1~2 and z is 1~5; The mixture is first ball-milled at low speed, then ball-milled at high speed; The ball-milled mixture is first cold-pressed, and then heat-treated under vacuum to obtain electrolyte sheets; The electrolyte sheet is pulverized, cold-pressed again, and then hot-pressed to prepare a solid electrolyte.

8. The preparation method according to claim 7, characterized in that, The conditions for low-speed ball milling include: a ball milling speed of 50 rpm to 150 rpm and a ball milling time of 10 min to 120 min; The conditions for high-speed ball milling include: adding ZrO2 grinding balls and milling them together with the raw materials; the diameter of the ZrO2 grinding balls is 3mm~10mm; the mass ratio of ZrO2 grinding balls to raw materials is 5~200:1; the ball milling speed is 400rpm~700rpm; and the ball milling time is 0.5h~300h. The conditions for cold pressing include: cold pressing pressure of 200MPa~500MPa and cold pressing time of 0.1min~10min; The conditions for hot pressing include: hot pressing pressure of 200MPa~500MPa, hot pressing temperature of 80℃~180℃, and hot pressing time of 5min~120min. The heat treatment conditions include: a heat treatment temperature of 150℃ to 600℃ and a heat treatment time of 10 min to 800 min.

9. An all-solid-state battery, characterized in that, The solid electrolyte includes the solid electrolyte according to any one of claims 1 to 5 or the solid electrolyte obtained by the preparation method according to any one of claims 6 to 8.

10. The all-solid-state battery according to claim 1, characterized in that, The all-solid-state battery also includes a positive electrode, a negative electrode, and a negative electrode interface layer; The positive electrode is prepared by grinding or low-speed ball milling of positive electrode active material and positive electrode filler. The positive electrode active material is at least one of LiCoO2, LiFePO4, NCM ternary material, lithium-rich phase lithium manganese oxide, lithiated layered oxide and lithiated layered sulfide. The positive electrode filler is at least one of conductive agent and ion-conducting agent made from the solid electrolyte. The conductive agent is at least one of graphite, carbon black, acetylene black, Ketjen black and carbon fiber. The negative electrode interface layer is at least one of sulfides, halides, and halide oxides.

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