Doped halide solid-state electrolyte and preparation method therefor, all-solid-state battery, and electric device

Abstract

A doped halide solid-state electrolyte and a preparation method therefor, an all-solid-state battery, and an electric device. The general formula of the doped halide solid-state electrolyte is Li6-ma-czAa+ mxBb+ myCc+ zX6, wherein a is the valence of the ion A, b is the valence of the ion B, c is the valence of the ion C, the value of a is 3 or 4, the value of b is 4, 5 or 6, the value of c is 2, 3, 4, 5 or 6, ax+by=a, b>a, x>y>0, 0≤z<0.5, 0<m<1.5, and mx+my+z<1. Compared with a parent matrix material, the doped halide solid-state electrolyte has a better ionic conductivity.

Description

Doped halide solid-state electrolyte, preparation method thereof, all-solid-state battery and electric device

[0001] Cross-reference to related applications

[0002] This application claims priority to Chinese Patent Application No. 202410464797.4, filed on April 17, 2024, entitled “Doped halide solid-state electrolyte, preparation method thereof, all-solid-state battery and electric device”, the entire contents of which are incorporated herein by reference. TECHNICAL FIELD

[0003] The present application relates to a doped halide solid-state electrolyte, a preparation method thereof, an all-solid-state battery and an electric device. BACKGROUND

[0004] Compared with liquid batteries, all-solid-state batteries use solid-state electrolytes, and are less likely to cause combustion and explosion, thus having high reliability. At present, the main obstacle for the commercialization of all-solid-state batteries is that the contact between the positive electrode and the electrolyte layer is solid-solid interface contact, and the ion transmission is difficult, which leads to high internal resistance of the all-solid-state battery, affecting its electrochemical performance.

[0005] SUMMARY

[0006] The present application provides a doped halide solid-state electrolyte, a preparation method thereof, an all-solid-state battery and an electric device, which has better ion conductivity performance than the original matrix material.

[0007] In a first aspect, the present application provides a doped halide solid-state electrolyte, the general formula of the doped halide solid-state electrolyte is Li 6-ma-cz A a+ mx B b+ my C c+ z X6, a is the valence of A ion, b is the valence of B ion, c is the valence of C ion, a is 3 or 4, b is 4, 5 or 6, c is 2, 3, 4, 5 or 6, ax+by=a, b>a, x>y>0, 0≤z<0.5, 0<m<1.5, mx+my+z<1; A includes one or more of Ga, In, Sc, Y, lanthanide metals, Sb, Bi, Ti, Zr, Hf, B includes one or more of Ti, Zr, Hf, V, Nb, Ta, Mo, W, C includes one or more of Mg, Ca, Sr, Ba, Ga, In, Sc, Y, lanthanide metals, Sb, Bi, Ti, Zr, Hf, V, Nb, Ta, Mo, W, and A, B, C are different; X includes one or more of halogens.

[0008] ax+by=a, b>a, after the introduction of B ions, the total charge number provided by A ions and B ions is consistent with the charge number provided by A ions alone before modification, so that when higher valence B ions are doped, the total occupation number of A ions and B ions is less than 1, that is, more A vacancies are generated, thereby reducing the hindrance of Coulomb repulsion for the migration of lithium ions, and realizing the improvement of ion conductivity. Doping C ions can regulate the content of lithium ions and induce more lithium vacancies. By adjusting the content of C ions, the doped halide solid-state electrolyte can have the same phase state and space group as the original matrix material. By adjusting the value of m, the lithium content of the doped halide solid-state electrolyte can be adjusted to realize the regulation between the lithium-poor state (i.e., high lithium ion vacancy number) and the lithium-rich state (i.e., high lithium ion concentration). Therefore, the doped halide solid-state electrolyte provided in the embodiments of the present application has better ion conductivity performance than the original matrix material, which is beneficial to realize its practical application in a full solid-state battery.

[0009] In some embodiments, 0<z≤0.2.

[0010] In some embodiments, a is 4, b is 5, and c is 2, 3, 4, or 5.

[0011] In some embodiments, 0.5≤m≤1.25.

[0012] In some embodiments, 0.5≤mx<1.

[0013] In some embodiments, the ionic radius of C ions is greater than the ionic radius of A ions, and the ionic radius of C ions is greater than the ionic radius of B ions. When the ionic radius of the doped C ions is greater than the ionic radius of A ions and greater than the ionic radius of B ions, the C ions can widen the cation interlayer spacing and further weaken the lithium ion migration resistance.

[0014] In some embodiments, A includes one or more of In, Y, Zr, and a lanthanide metal.

[0015] In some embodiments, B includes one or more of Zr, Hf, Nb, and Ta.

[0016] In some embodiments, C includes one or more of Ca, In, La, Ce, Pr, Nd, Sm, Eu, Gd, Zr, Hf, Nb, Ta, and Mo, and A, B, and C are different.

[0017] In some embodiments, X includes one or more of Cl, Br, and I.

[0018] In some embodiments, the doped halide solid-state electrolyte is any one of a glass phase, a glass-ceramic phase, and a crystalline phase.

[0019] In some embodiments, the volume - distribution particle size Dv50 of the doped halide solid electrolyte is 0.5 μm - 10 μm.

[0020] In some embodiments, the ionic conductivity of the doped halide solid electrolyte at 25 °C is 0.5 mS / cm - 15 mS / cm.

[0021] In a second aspect, the present application provides a method for preparing a doped halide solid electrolyte, comprising the following steps: uniformly mixing a halide of element Li, a halide of element A, a halide of element B, and optionally a halide of element C in proportion, then grinding under a protective gas atmosphere, and annealing the ground material under a protective gas atmosphere to obtain a doped halide solid electrolyte. The general formula of the doped halide solid electrolyte is Li 6-ma - cz A a+ mx B b+ my C c+ z X6, where a is the valence of A ions, b is the valence of B ions, c is the valence of C ions, a is 3 or 4, b is 4, 5 or 6, c is 2, 3, 4, 5 or 6, ax + by = a, b > a, x > y > 0, 0 ≤ z < 0.5, 0 < m < 1.5, mx + my + z < 1; A includes one or more of Ga, In, Sc, Y, lanthanide metals, Sb, Bi, Ti, Zr, Hf; B includes one or more of Ti, Zr, Hf, V, Nb, Ta, Mo, W; C includes one or more of Mg, Ca, Sr, Ba, Ga, In, Sc, Y, lanthanide metals, Sb, Bi, Ti, Zr, Hf, V, Nb, Ta, Mo, W, and A, B, C are different; X includes one or more of halogens.

[0022] In some embodiments, the rotation speed of grinding is 300 rpm - 600 rpm, and optionally 400 rpm - 550 rpm.

[0023] In some embodiments, the grinding time is 6 h - 72 h, and optionally 12 h - 48 h.

[0024] In some embodiments, the annealing temperature is 100 °C - 300 °C, and optionally 100 °C - 200 °C.

[0025] In some embodiments, the annealing time is 2 h - 24 h, and optionally 5 h - 12 h.

[0026] In a third aspect, the present application provides a full solid-state battery, comprising a positive electrode, wherein the positive electrode comprises a positive electrode active material and the doped halide solid-state electrolyte according to the first aspect of the present application or prepared by the preparation method according to the second aspect of the present application.

[0027] The doped halide solid-state electrolyte has better ionic conductivity performance than the original matrix material, can improve the problem of poor solid-solid interface contact, thereby being beneficial to the performance of the full solid-state battery, and making the full solid-state battery have high initial coulombic efficiency and good cycle stability.

[0028] In some embodiments, the mass ratio of the positive electrode active material to the doped halide solid-state electrolyte is 90:10 to 70:30.

[0029] In some embodiments, the positive electrode active material comprises one or more of lithium cobaltate and modified materials thereof, lithium iron phosphate and modified materials thereof, lithium iron manganese phosphate and modified materials thereof, lithium nickel cobalt manganese oxide and modified materials thereof, lithium nickel cobalt aluminum oxide and modified materials thereof, lithium nickel oxide and modified materials thereof, lithium manganese oxide and modified materials thereof, lithium titanate, sulfur, selenium, tellurium.

[0030] In some embodiments, the full solid-state battery further comprises a negative electrode and an electrolyte layer, wherein the electrolyte layer is located between the positive electrode and the negative electrode, and the negative electrode comprises one or more of graphite, graphene, carbon nanotubes, mesocarbon microbeads, soft carbon, hard carbon, silicon-based materials, tin-based materials, lithium titanate, metal oxides, metallic lithium, lithium alloys, lithium composite materials.

[0031] In a fourth aspect, the present application provides a power utilization device comprising the full solid-state battery according to the third aspect of the present application.

[0032] The power utilization device according to the present application comprises the full solid-state battery provided by the present application, and thus has at least the same advantages as the full solid-state battery. BRIEF DESCRIPTION OF DRAWINGS

[0033] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required to be used in the embodiments of the present application will be briefly introduced as follows. Obviously, the drawings described below are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of the drawings.

[0034] FIG. 1 is a schematic diagram of an embodiment of a battery cell according to the present application.

[0035] FIG. 2 is an exploded schematic diagram of an embodiment of a battery cell according to the present application.

[0036] FIG. 3 is a schematic diagram of an embodiment of a battery module according to the present application.

[0037] FIG. 4 is a schematic view of an embodiment of a battery pack of the present application.

[0038] FIG. 5 is an exploded schematic view of the embodiment of the battery pack shown in FIG. 4.

[0039] FIG. 6 is a schematic view of an embodiment of an electric device including an all-solid-state battery of the present application as a power source.

[0040] In the drawings, the drawings are not necessarily drawn to scale. Reference signs are explained as follows: 1 battery pack, 2 upper case, 3 lower case, 4 battery module, 5 battery cell, 51 case, 52 electrode assembly, 53 cover plate. DETAILED DESCRIPTION

[0041] Hereinafter, embodiments of a doped halide solid-state electrolyte and a method for producing the same, an all-solid-state battery, and an electric device of the present application are specifically disclosed while appropriately referring to the drawings. However, there are cases where unnecessary detailed explanations are omitted. For example, there are cases where detailed explanations of matters that are already well known, repeated explanations of actually identical structures are omitted. This is to avoid the following description from becoming unnecessarily lengthy and to facilitate understanding by those skilled in the art. In addition, the drawings and the following explanations are provided so that those skilled in the art can fully understand the present application, and are not intended to limit the subject matter recited in the claims.

[0042] The "ranges" disclosed in the present application are defined in the form of lower and upper limits, and a given range is defined by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundaries of a particular range. The ranges defined in this way can be inclusive or exclusive of the end values, and can be arbitrarily combined, i.e., any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60-120 and 80-110 are listed for a particular parameter, it is understood that ranges of 60-110 and 80-120 are also contemplated. In addition, if a minimum range value of 1 and 2 is listed, and if a maximum range value of 3, 4, and 5 is listed, then the following ranges are all contemplated: 1-3, 1-4, 1-5, 2-3, 2-4, and 2-5. In the present application, unless otherwise stated, a numerical range "a-b" represents a shorthand manner of describing each and every numerical value that is contained in the range between "a" and "b," wherein "a" and "b" are both real numbers. For example, the numerical range "0-5" indicates that all real numbers between "0" and "5" have been listed herein, and "0-5" is merely a shorthand manner of describing those numerical combinations. In addition, when it is stated that a parameter is an integer ≥ 2, it is equivalent to disclose that the parameter is, for example, an integer of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, and the like.

[0043] If not particularly specified, all the embodiments and optional embodiments of the present application can be combined with each other to form new technical solutions, and such technical solutions should be considered to be included in the disclosure of the present application.

[0044] If not particularly specified, all the technical features and optional technical features of the present application can be combined with each other to form new technical solutions, and such technical solutions should be considered to be included in the disclosure of the present application.

[0045] If not particularly specified, all the steps of the present application can be performed in sequence or randomly, and preferably in sequence. For example, the method comprises steps (a) and (b), which means that the method can comprise steps (a) and (b) performed in sequence, or steps (b) and (a) performed in sequence. For example, the method can further comprise step (c), which means that step (c) can be added to the method in any order, for example, the method can comprise steps (a), (b) and (c), or steps (a), (c) and (b), or steps (c), (a) and (b), etc.

[0046] Unless otherwise specified, the terms used in the present application have the commonly understood meanings understood by those skilled in the art.

[0047] Unless otherwise specified, the values of the parameters mentioned in the present application can be measured by various test methods commonly used in the art, for example, by the test methods given in the examples of the present application. Unless otherwise specified, the test temperature of each parameter is 25°C.

[0048] The all-solid-state battery mentioned in the examples of the present application can be a single physical module comprising one or more battery cells to provide higher voltage and capacity. For example, the all-solid-state battery mentioned in the present application can comprise a battery cell, a battery module or a battery pack, etc.

[0049] The battery cell is the smallest unit that constitutes the all-solid-state battery, which can independently realize the functions of charging and discharging. The battery cell can be in the shape of a cylinder, a cuboid or other shapes, which are not limited in the examples of the present application. For example, FIG. 1 is a battery cell 5 in the shape of a cuboid as an example.

[0050] When there are multiple battery cells, the multiple battery cells are connected in series, in parallel, or in a hybrid manner through a busbar. In some embodiments, the all-solid-state battery can be a battery module; when there are multiple battery cells, the multiple battery cells are arranged and fixed to form a battery module. In some embodiments, the all-solid-state battery can be a battery pack, which includes a box body and battery cells, and the battery cells or battery modules are accommodated in the box body. In some embodiments, the box body can be part of the chassis structure of the vehicle. For example, part of the box body can be at least part of the floor of the vehicle, or part of the box body can be at least part of the cross beam and longitudinal beam of the vehicle.

[0051] In some embodiments, the all-solid-state battery can be an energy storage device. The energy storage device includes an energy storage container, an energy storage cabinet, etc.

[0052] The battery cell includes an electrode assembly and an outer package. The outer package can be used to encapsulate the electrode assembly. The outer package can be a hard shell, such as a hard plastic shell, an aluminum shell, a steel shell, etc. The outer package can also be a soft package, such as a pouch-type soft package. The material of the soft package can be plastic, such as one or more of aluminum plastic film, polypropylene (PP), polybutylene terephthalate (PBT), and polybutylene succinate (PBS).

[0053] In some embodiments, as shown in FIG. 2, the outer package can include a shell 51 and a cover plate 53. The shell 51 can include a bottom plate and a side plate connected to the bottom plate, and the bottom plate and the side plate enclose a receiving cavity. The shell 51 has an opening communicating with the receiving cavity, and the cover plate 53 is used to cover the opening to close the receiving cavity. The electrode assembly 52 is encapsulated in the receiving cavity. The number of electrode assemblies 52 contained in the battery cell 5 can be one or more, which can be adjusted according to requirements.

[0054] In some embodiments, the battery cell can be assembled into a battery module, and the number of battery cells contained in the battery module can be multiple, and the specific number can be adjusted according to the application and capacity of the battery module. As shown in FIG. 3, in the battery module 4, the multiple battery cells 5 can be arranged in sequence along the length direction of the battery module 4. Of course, other arbitrary arrangements can also be used. Further, the multiple battery cells 5 can be fixed by fasteners.

[0055] Optionally, the battery module 4 can further include a housing having a receiving space, and the multiple battery cells 5 are accommodated in the receiving space.

[0056] In some embodiments, the above-mentioned battery module can also be assembled into a battery pack, and the number of battery modules contained in the battery pack can be adjusted according to the application and capacity of the battery pack.

[0057] As shown in FIGS. 4 and 5, a plurality of battery modules 4 can be included in the battery pack 1 in a case and disposed in the case. The case includes an upper case 2 for capping a lower case 3 and forms an enclosed space for accommodating the battery modules 4. The plurality of battery modules 4 can be arranged in the case in any manner.

[0058] Sulfide solid electrolytes are considered as key materials for realizing industrialization of all-solid-state batteries because of their high ionic conductivity, low Young's modulus, and other advantages. However, sulfide solid electrolytes have problems such as poor positive electrode stability, high cost, and easy decomposition to release toxic gases. Therefore, it is necessary to find other suitable solid electrolytes for the positive electrode in addition to sulfide solid electrolytes. Halide solid electrolytes have similar physicochemical properties to sulfide solid electrolytes and also have a low Young's modulus, so that they can form good interface contact with electrode materials. In addition, halide solid electrolytes have much better positive electrode stability than sulfide solid electrolytes due to the characteristics of halide anions, so that the first coulomb efficiency and cycle stability of all-solid-state batteries can be simultaneously improved. However, the ionic conductivity of halide solid electrolytes is generally not high, which limits their application in the industrialization of all-solid-state batteries. Current industry is still exploring modification strategies for halide solid electrolytes in order to greatly improve their ionic conductivity.

[0059] Based on this, the embodiments of the present application provide a doped halide solid electrolyte, which has better ionic conductivity than the undoped halide solid electrolyte matrix material, and can be used in the positive electrode of an all-solid-state battery to improve the specific capacity of the positive electrode active material and improve the cycle performance of the all-solid-state battery.

[0060] The general formula of the doped halide solid electrolyte provided by the embodiments of the present application is Li 6-ma-cz A a+ mx B b+ my C c+ z X6.

[0061] a is the valence of the A ion, b is the valence of the B ion, and c is the valence of the C ion, a is 3 or 4, b is 4, 5, or 6, c is 2, 3, 4, 5, or 6, ax+by=a, b>a, x>y>0, 0≤z<0.5, 0<m<1.5, mx+my+z<1.

[0062] A comprises one or more of Ga, In, Sc, Y, lanthanide metals, Sb, Bi, Ti, Zr, Hf, B comprises one or more of Ti, Zr, Hf, V, Nb, Ta, Mo, W, C comprises one or more of Mg, Ca, Sr, Ba, Ga, In, Sc, Y, lanthanide metals, Sb, Bi, Ti, Zr, Hf, V, Nb, Ta, Mo, W, and A, B, C are different. X comprises one or more of halogens.

[0063] x>y>0, the doping type halide solid-state electrolyte provided by the embodiment of the present application is based on a halide solid-state electrolyte matrix material Li 6-a A a+ X6 is modified. 0≤z<0.5, which means that the doping type halide solid-state electrolyte can or can not be doped with C ions.

[0064] ax+by=a, b>a, after the introduction of B ions, the total charge number provided by A ions and B ions is consistent with the charge number provided by A ions alone before modification, so that when higher valence B ions are doped, the total occupation number of A ions and B ions is less than 1, that is, more A vacancies are generated, thereby reducing the hindrance of Coulomb repulsion for the migration of lithium ions, and realizing the improvement of ion conductivity.

[0065] In addition, whether or not C ions are doped, mx+my+z<1 must be satisfied, thereby generating more A vacancies, reducing the hindrance of Coulomb repulsion for the migration of lithium ions, and realizing the improvement of ion conductivity. Doping C ions can regulate the content of lithium ions and induce more lithium vacancies. In addition, adjusting the content of C ions can make the doping type halide solid-state electrolyte have the same phase state and space group as the original matrix material.

[0066] m is a coefficient for adjusting the lithium-poor state and the lithium-rich state. 0<m<1.5, by adjusting the value of m, the lithium content of the doping type halide solid-state electrolyte can be adjusted to realize the regulation between the lithium-poor state (i.e., high lithium ion vacancy number) and the lithium-rich state (i.e., high lithium ion concentration). Lithium ion vacancy number and lithium ion concentration are two important factors affecting the ion conductivity of the doping type halide solid-state electrolyte, but these two factors are antagonistic. Different all-solid-state batteries have different requirements for the doping type halide solid-state electrolyte. Therefore, by adjusting the value of m, the doping type halide solid-state electrolyte can be switched between the lithium-poor state and the lithium-rich state, and the structural design is more free, and the battery application is more extensive.

[0067] Therefore, the doping type halide solid-state electrolyte provided by the embodiment of the present application has better ion conductivity performance than the original matrix material, which is conducive to realizing its practical application in all-solid-state batteries.

[0068] In some embodiments, optionally, the lanthanide metal can include one or more of La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu.

[0069] In some embodiments, optionally, 0.5≤m≤1.25.

[0070] In some embodiments, optionally, 0≤z≤0.2. More optionally, 0<z≤0.2.

[0071] In some embodiments, optionally, a is 4, b is 5, and c is 2, 3, 4, or 5; or, a is 3, b is 4 or 5, and c is 2, 3, 4, or 5.

[0072] In some embodiments, optionally, 0.5≤mx<1. More optionally, 0.6≤mx<1, 0.65≤mx<1, 0.7≤mx<1, 0.75≤mx<1, 0.8≤mx<1.

[0073] In some embodiments, optionally, the ionic radius of the C ion is larger than the ionic radius of the A ion, and the ionic radius of the C ion is larger than the ionic radius of the B ion.

[0074] When the ionic radius of the C ion is larger than the ionic radius of the A ion, and the ionic radius of the C ion is larger than the ionic radius of the B ion, the C ion can play a role in widening the cation interlayer spacing, further weakening the lithium ion migration resistance, thereby enabling the doped halide solid-state electrolyte to have better ionic conductivity performance.

[0075] In some embodiments, optionally, A can include one or more of In, Y, Zr, a lanthanide metal.

[0076] In some embodiments, optionally, B can include one or more of Zr, Hf, Nb, Ta.

[0077] In some embodiments, optionally, C can include one or more of Ca, In, La, Ce, Pr, Nd, Sm, Eu, Gd, Zr, Hf, Nb, Ta, Mo, and A, B, C are different.

[0078] X includes one or more of halogens, in some embodiments, optionally, X can include one or more of F, Cl, Br, I. More optionally, X can include one or more of Cl, Br, I.

[0079] For example, X6may be F6, Cl6, Br6, I6, F x Cl 6-x , Cl x Br 6-x , Cl x I6-x Any one of the above, x is greater than 0 and less than 6.

[0080] The doped halide solid-state electrolyte can be any one of a glass phase, a glass-ceramic phase, a crystalline phase.

[0081] In some embodiments, the volume distribution particle size Dv50 of the doped halide solid-state electrolyte can be 0.5-10 μm.

[0082] In some embodiments, the ion conductivity of the doped halide solid-state electrolyte at 25℃ can be 0.5-15 mS / cm. The matrix material Li 6-a A a+ The ion conductivity of the doped halide solid-state electrolyte is different due to different X6, different kinds and contents of doped elements (e.g. B, C), and different m values.

[0083] The application also provides a preparation method of the above doped halide solid-state electrolyte.

[0084] The preparation method comprises the following steps: uniformly mixing halides of elements Li, halides of element A, halides of element B, and optional halides of element C in proportion, then performing grinding under a protective gas atmosphere, and then performing annealing of the ground material under a protective gas atmosphere to obtain the doped halide solid-state electrolyte. The molar ratio of the elements Li, element A, element B, and element C is (6-ma-cz):mx:my:z, a is the valence of A ions, b is the valence of B ions, c is the valence of C ions, a is 3 or 4, b is 4, 5 or 6, c is 2, 3, 4, 5 or 6, ax+by=a, b>a, x>y>0, 0≤z<0.5, 0<m<1.5, mx+my+z<1. A comprises one or more of Ga, In, Sc, Y, lanthanide metals, Sb, Bi, Ti, Zr, Hf, B comprises one or more of Ti, Zr, Hf, V, Nb, Ta, Mo, W, C comprises one or more of Mg, Ca, Sr, Ba, Ga, In, Sc, Y, lanthanide metals, Sb, Bi, Ti, Zr, Hf, V, Nb, Ta, Mo, W, and A, B and C are different. The general formula of the doped halide solid-state electrolyte is Li 6-ma-cz A a+ mx B b+ my C c+ z X6. X comprises one or more of halogens.

[0085] When the doped halide solid-state electrolyte is prepared, ax+by=a, b>a is adjusted, and after the B ion is introduced, the total charge number provided by the A ion and the B ion is consistent with the charge number provided by the A ion before modification, so that when the B ion of a higher valence state is incorporated, the total occupation number of the A ion and the B ion is less than 1, that is, more A vacancies are generated, thereby reducing the hindrance of Coulomb repulsion for the migration of lithium ions, and realizing the improvement of ion conductivity.

[0086] When the doped halide solid-state electrolyte is prepared, mx+my+z<1 can generate more A vacancies, can reduce the hindrance of Coulomb repulsion for the migration of lithium ions, and realize the improvement of ion conductivity.

[0087] The incorporated C ion can regulate the content of lithium ions and induce more lithium vacancies. In addition, by adjusting the content of the C ion, the doped halide solid-state electrolyte can have the same phase state and space group as the original matrix material.

[0088] m is a coefficient for adjusting the lithium-poor state and the lithium-rich state. 0<m<1.5, by adjusting the value of m, the lithium content of the doped halide solid-state electrolyte can be adjusted to realize the regulation between the lithium-poor state (i.e. high lithium ion vacancy number) and the lithium-rich state (i.e. high lithium ion concentration). Lithium ion vacancy number and lithium ion concentration are two important factors affecting the ion conductivity of the doped halide solid-state electrolyte, but these two factors are antagonistic. Different all-solid-state batteries have different requirements for doped halide solid-state electrolytes. Therefore, by adjusting the value of m, the doped halide solid-state electrolyte can be switched between the lithium-poor state and the lithium-rich state, and the structural design is more free, and the battery application is more extensive.

[0089] In the embodiments of the present application, the above-mentioned doped halide solid-state electrolyte is prepared by grinding and annealing, which can effectively realize the uniformity of doping and the stability of structure, so as to realize the smoothness of ion migration channel, and obtain a doped halide solid-state electrolyte with high ion conductivity.

[0090] In some embodiments, the rotation speed of grinding can be 300rpm-600rpm, for example, it can be 300rpm, 325rpm, 350rpm, 375rpm, 400rpm, 425rpm, 450rpm, 475rpm, 500rpm, 525rpm, 550rpm, 575rpm, 600rpm, or a range consisting of any of the above values.

[0091] Alternatively, the rotation speed of grinding can be 400rpm-550rpm.

[0092] In some embodiments, the grinding time can be 6h-72h, for example, can be 6h, 8h, 10h, 16h, 22h, 28h, 34h, 40h, 48h, 56h, 64h, 72h, or a range consisting of any of the above values.

[0093] Optionally, the grinding time can be 12h-48h.

[0094] In some embodiments, the grinding can be ball milling. Optionally, the ball milling can be preceded by manual grinding. Optionally, the manual grinding time can be 10min-30min.

[0095] In some embodiments, the annealing temperature can be 100℃-300℃, for example, can be 100℃, 120℃, 140℃, 160℃, 180℃, 200℃, 220℃, 240℃, 260℃, 280℃, 300℃, or a range consisting of any of the above values.

[0096] Optionally, the annealing temperature can be 100℃-200℃.

[0097] In some embodiments, the annealing time can be 2h-24h, for example, can be 2h, 5h, 8h, 10h, 12h, 14h, 16h, 18h, 20h, 22h, 24h, or a range consisting of any of the above values.

[0098] Optionally, the annealing time can be 5h-12h.

[0099] By adjusting the grinding parameters and the annealing parameters, the doped halide solid-state electrolyte can have higher ionic conductivity.

[0100] Optionally, the protective gas can include argon.

[0101] The battery cell includes a positive electrode, a negative electrode, and an electrolyte layer.

[0102] The positive electrode includes a positive electrode active material and the doped halide solid-state electrolyte provided in the embodiments of the present application.

[0103] The doped halide solid-state electrolyte provided in the embodiments of the present application has better ionic conductivity performance compared to the original matrix material, can improve the problem of poor solid-solid interface contact, thereby being conducive to the performance of the electrochemical performance of the all-solid-state battery, and making it have high initial coulombic efficiency and good cycle stability.

[0104] Compared with the sulfide solid-state electrolyte, the doped halide solid-state electrolyte provided in the embodiments of the present application has good positive electrode stability, can also match high-voltage positive electrode active materials, and further improves the energy density of the all-solid-state battery.

[0105] Optionally, the mass ratio of the positive electrode active material to the doped halide solid-state electrolyte can be 90:10 to 70:30, for example, can be 90:10, 88:12, 86:14, 84:16, 82:18, 80:20, 78:22, 76:24, 74:26, 72:28, 70:30, or a range consisting of any of the aforementioned values.

[0106] Optionally, the positive electrode active material can include one or more of lithium cobaltate and modified materials thereof, lithium iron phosphate and modified materials thereof, lithium manganese iron phosphate and modified materials thereof, lithium nickel cobalt manganese acid and modified materials thereof, lithium nickel cobalt aluminum acid and modified materials thereof, lithium nickel acid and modified materials thereof, lithium manganese acid and modified materials thereof, lithium titanium acid, sulfur, selenium, tellurium. The modified materials of each of the above positive electrode active materials can be doped modification and / or surface coating modification of the positive electrode active material.

[0107] As an example, the positive electrode active material can include, but is not limited to, LiCoO2, LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2(simplified as NCM333), LiNi 0.5 Co 0.2 Mn 0.3 O2(simplified as NCM523), LiNi 0.5 Co 0.25 Mn 0.25 O2(simplified as NCM211), LiNi 0.6 Co 0.2 Mn 0.2 O2(simplified as NCM622), LiNi 0.8 Co 0.1 Mn 0.1 O2(simplified as NCM811), LiNi 0.96 Co 0.02 Mn 0.02 O2(simplified as Ni96), LiNi 0.80 Co 0.15 Al 0.05 O2, LiFePO4, and modified materials thereof, respectively.

[0108] The battery cell will be accompanied by Li deintercalation and consumption during charging and discharging process, and the molar content of Li is different when the battery cell is discharged to different states. In the enumeration of the positive active material in this application, the molar content of Li is the initial state of the material, i.e. the state before feeding, and the positive active material is applied to the battery cell. After charging and discharging cycle, the molar content of Li will change. In the enumeration of the positive active material in this application, the molar content of O is only the theoretical state value, and the lattice oxygen release will cause the change of the molar content of O. The actual molar content of O will also appear floating.

[0109] The positive electrode also includes a positive electrode conductive agent. As an example, the positive electrode conductive agent can include, but is not limited to, one or more of super P, conductive graphite, acetylene black, carbon black, ketjen black, carbon dots, carbon nanotubes, graphene, and vapor grown carbon fiber (VGCF).

[0110] The positive electrode can be prepared by a dry method, for example, the positive electrode active material, the positive electrode conductive agent, etc. can be formed by pressing, or can be prepared by a wet method.

[0111] The positive electrode can include a positive electrode binder, or can not include a positive electrode binder, which can be adjusted according to the preparation process of the positive electrode and the battery cell.

[0112] In some embodiments, the positive electrode includes a positive electrode binder. As an example, the positive electrode binder can include, but is not limited to, one or more of polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene terpolymer, tetrafluoroethylene-hexafluoropropylene copolymer, polyethylene oxide, fluorine-containing acrylic ester resin, styrene butadiene rubber (SBR), water-soluble unsaturated resin SR-1B, water-based acrylic resin (e.g., polyacrylic acid PAA, polymethylacrylic acid PMAA, sodium polyacrylate PAAS), polyacrylamide (PAM), polyvinyl alcohol (PVA), sodium alginate (SA), and carboxymethyl chitosan (CMCS).

[0113] The positive electrode can or can not include a positive electrode current collector, for example, a stainless steel sheet of a mold battery can be used as a positive electrode current collector. In some embodiments, the positive electrode includes a positive electrode current collector, and the positive electrode active material and the doped halide solid-state electrolyte are located on at least one surface of the positive electrode current collector. The positive electrode current collector can be a metal foil or a composite current collector. As an example of a metal foil, an aluminum foil can be used. The composite current collector can include a polymer material base layer and a metal material layer formed on at least one surface of the polymer material base layer. As an example, the metal material can include, but is not limited to, one or more of aluminum, an aluminum alloy, nickel, a nickel alloy, titanium, a titanium alloy, silver, and a silver alloy. As an example, the polymer material base layer can include, but is not limited to, one or more of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), and polyethylene (PE).

[0114] The negative electrode includes a negative electrode active material, which can include one or more of graphite, graphene, carbon nanotubes, mesocarbon microbeads, soft carbon, hard carbon, silicon-based materials, tin-based materials, lithium titanate, metal oxides, metallic lithium, lithium alloys, lithium composite materials.

[0115] The silicon-based material can include one or more of elemental silicon, silicon oxide, silicon carbide, and silicon alloys. The tin-based material can include one or more of elemental tin, tin oxide, and tin alloys. The metal oxide includes one or more of TiO2, MoO2, In2O3, Al2O3, Cu2O, VO2, Ga2O3, Sb2O5, and Bi2O5. Other elements in the lithium alloy can include one or more of In, Mg, Al, Zn, Sn, Ag, Au, Ga, Pt, and Fe, for example, can be Li-In alloy, Li-Mg alloy, Li-Al alloy, Li-Zn alloy, Li-Fe alloy, etc.

[0116] The negative electrode can be a metal sheet, for example, a lithium sheet, a lithium alloy sheet, etc., and can also be prepared by a dry method, for example, the negative electrode active material, etc. can be formed by pressing, and can also be prepared by a wet method.

[0117] In some embodiments, the negative electrode can also include a negative electrode conductive agent. As an example, the negative electrode conductive agent can include, but is not limited to, one or more of super-conductive carbon, conductive graphite, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.

[0118] In some embodiments, the negative electrode can further include a negative electrode binder. As an example, the negative electrode binder can include, but is not limited to, one or more of styrene butadiene rubber (SBR), water-soluble unsaturated resin SR-1B, water-based acrylic resin (e.g., polyacrylic acid PAA, polymethylacrylic acid PMAA, sodium polyacrylate PAAS), polyacrylamide (PAM), polyvinyl alcohol (PVA), sodium alginate (SA), and carboxymethyl chitosan (CMCS).

[0119] The negative electrode can or can not include a negative electrode current collector, for example, a stainless steel sheet of a dielectric battery can be used as a negative electrode current collector. In some embodiments, the negative electrode includes a negative electrode current collector, and the negative electrode active material is located on at least one surface of the negative electrode current collector. The negative electrode current collector can include a metal foil, a three-dimensional porous current collector, or a composite current collector. As an example of the metal foil, a copper foil, a copper alloy foil, a nickel foil, a nickel alloy foil, an aluminum foil, or an aluminum alloy foil can be used. As an example of the three-dimensional porous current collector, a copper mesh, a nickel mesh, an aluminum mesh, a copper foam, a nickel foam, or an aluminum foam can be used. The composite current collector can include a polymer material base layer and a metal material layer formed on at least one surface of the polymer material base layer. As an example, the metal material can include, but is not limited to, one or more of copper, copper alloy, aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy. As an example, the polymer material base layer can include, but is not limited to, one or more of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), and polyethylene (PE).

[0120] The electrolyte layer includes a solid-state electrolyte material. The solid-state electrolyte material includes one or more of a sulfide solid-state electrolyte, a halide solid-state electrolyte. Optionally, the solid-state electrolyte material includes a sulfide solid-state electrolyte.

[0121] The battery cell can be prepared by a method known in the art, for example, the assembly of the battery cell includes, but is not limited to, a button cell, a dielectric battery, a prismatic cell, a pouch cell, etc.

[0122] In some embodiments, the method for preparing the battery cell includes the following steps: grinding the doped halide solid-state electrolyte, the positive electrode active material, and the positive electrode conductive agent to obtain a positive electrode powder; adding the solid-state electrolyte for forming the electrolyte layer into a model battery, and performing a first cold pressing process; adding the positive electrode powder to one side of the model battery, and performing a second cold pressing process; adding the negative electrode to the other side of the model battery, and performing a third cold pressing process, thereby obtaining the battery cell.

[0123] Electric device

[0124] The embodiments of the present application also provide a power consuming device, which comprises the battery provided by the embodiments of the present application. The battery can be used as a power source of the power consuming device, or can be used as an energy storage unit of the power consuming device. The power consuming device can be, but is not limited to, a mobile device (such as a mobile phone, a tablet computer, a notebook computer, etc.), an electric vehicle (such as a pure electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, an electric bicycle, an electric scooter, an electric golf cart, an electric truck, etc.), an electric train, a ship and a satellite, an energy storage system, etc.

[0125] The power consuming device can select the type of the all-solid-state battery according to its use requirements, such as a battery monomer, a battery module or a battery pack.

[0126] As shown in FIG. 6, the power consuming device as an example can be a pure electric vehicle, a hybrid electric vehicle, or a plug-in hybrid electric vehicle, etc. In order to meet the requirements of high power and high energy density of the power consuming device, a battery pack or a battery module can be used.

[0127] The power consuming device as another example can be a mobile phone, a tablet computer, a notebook computer, etc. The power consuming device usually requires thinning, and a battery monomer can be used as a power source.

[0128] Embodiments

[0129] The embodiments described below more specifically describe the disclosure of the present application, which are only used for illustrative purposes, because various modifications and changes within the scope of the disclosure of the present application are obvious to those skilled in the art. Unless otherwise stated, all parts, percentages and ratios reported in the following embodiments are based on weight, and all reagents used in the embodiments are commercially available or synthesized according to conventional methods, and can be used directly without further treatment, and the instruments used in the embodiments are commercially available.

[0130] Embodiment 1

[0131] The doped halide solid-state electrolyte is Li2Zr 0.9 Nb 0.08 Cl6.

[0132] The raw materials 84.78 mg of LiCl, 209.74 mg of ZrCl4 and 21.61 mg of NbCl5 meeting the expected stoichiometric ratio are uniformly mixed, transferred into a ball mill pot after manual grinding for 20 min, and ball milled at 400 rpm for 12 h under an argon atmosphere; then the ground material is transferred into a muffle furnace, annealed at 100°C under an argon atmosphere for 6 h, and the doped halide solid-state electrolyte is obtained after the end of the annealing.

[0133] Embodiment 2

[0134] The doped halide solid-state electrolyte is Li 1.97 Zr 0.9 Nb 0.08 Ce 0.01 Cl6.

[0135] The raw materials 83.51 mg of LiCl, 209.74 mg of ZrCl4, 21.61 mg of NbCl5, and 2.46 mg of CeCl3 in the expected stoichiometric ratio were uniformly mixed, and after manual grinding for 20 min, they were transferred to a ball mill tank and ball milled at 400 rpm for 12 h in an argon atmosphere; then the ground material was transferred to a muffle furnace and annealed at 100°C for 6 h in an argon atmosphere, and after the end, the doped halide solid-state electrolyte was obtained.

[0136] Example 3

[0137] The doped halide solid-state electrolyte is Li2Zr 0.8 Nb 0.16 Cl6.

[0138] The raw materials 84.78 mg of LiCl, 186.43 mg of ZrCl4, and 43.22 mg of NbCl5 in the expected stoichiometric ratio were uniformly mixed, and after manual grinding for 20 min, they were transferred to a ball mill tank and ball milled at 400 rpm for 12 h in an argon atmosphere; then the ground material was transferred to a muffle furnace and annealed at 100°C for 6 h in an argon atmosphere, and after the end, the doped halide solid-state electrolyte was obtained.

[0139] Example 4

[0140] The doped halide solid-state electrolyte is Li 1.97 Zr 0.8 Nb 0.16 Ce 0.01 Cl6.

[0141] The raw materials 83.51 mg of LiCl, 186.43 mg of ZrCl4, 43.22 mg of NbCl5, and 2.46 mg of CeCl3 in the expected stoichiometric ratio were uniformly mixed, and after manual grinding for 20 min, they were transferred to a ball mill tank and ball milled at 400 rpm for 12 h in an argon atmosphere; then the ground material was transferred to a muffle furnace and annealed at 100°C for 6 h in an argon atmosphere, and after the end, the doped halide solid-state electrolyte was obtained.

[0142] Example 5

[0143] The doped halide solid-state electrolyte is Li 2.77 Zr 0.64 Nb 0.128 Ce 0.01 Cl6.

[0144] The raw materials 117.42 mg of LiCl, 149.15 mg of ZrCl4, 34.58 mg of NbCl5, and 2.46 mg of CeCl3 in the expected stoichiometric ratio were uniformly mixed, transferred into a ball mill jar after manual grinding for 20 min, and ball-milled at 400 rpm for 12 h under an argon atmosphere; then the ground material was transferred into a muffle furnace and annealed at 100 °C for 6 h under an argon atmosphere, and the doped halide solid-state electrolyte was obtained after the end of the process.

[0145] Example 6

[0146] The doped halide solid-state electrolyte was Li2ZrCl6. 1.97 Zr 0.8 Ta 0.16 La 0.01 Cl6.

[0147] The raw materials 83.51 mg of LiCl, 186.43 mg of ZrCl4, 57.31 mg of TaCl5, and 2.45 mg of LaCl3 in the expected stoichiometric ratio were uniformly mixed, transferred into a ball mill jar after manual grinding for 20 min, and ball-milled at 400 rpm for 12 h under an argon atmosphere; then the ground material was transferred into a muffle furnace and annealed at 100 °C for 6 h under an argon atmosphere, and the doped halide solid-state electrolyte was obtained after the end of the process.

[0148] Comparative Example 1

[0149] The doped halide solid-state electrolyte was Li2ZrCl6.

[0150] The raw materials 84.78 mg of LiCl and 233.04 mg of ZrCl4 in the expected stoichiometric ratio were uniformly mixed, transferred into a ball mill jar after manual grinding for 20 min, and ball-milled at 400 rpm for 12 h under an argon atmosphere; then the ground material was transferred into a muffle furnace and annealed at 100 °C for 6 h under an argon atmosphere, and the doped halide solid-state electrolyte was obtained after the end of the process.

[0151] Comparative Example 2

[0152] The doped halide solid-state electrolyte was Li2ZrCl6. 1.9 Zr 0.9 Nb 0.1 Cl6.

[0153] The raw materials 80.54 mg of LiCl, 209.74 mg of ZrCl4 and 27.02 mg of NbCl5 in the expected stoichiometric ratio were uniformly mixed, and after manual grinding for 20 min, they were transferred to a ball mill tank and ball-milled at 400 rpm for 12 h under an argon atmosphere; then the ground material was transferred to a muffle furnace and annealed at 100°C under an argon atmosphere for 6 h, and after the end of the process, the doped halide solid-state electrolyte was obtained.

[0154] Example 7

[0155] The doped halide solid-state electrolyte was Li3NbCl6. 2.98 Y 0.8 Zr 0.15 Ca 0.01 Cl6.

[0156] The raw materials 80.54 mg of LiCl, 209.74 mg of ZrCl4 and 27.02 mg of NbCl5 in the expected stoichiometric ratio were uniformly mixed, and after manual grinding for 20 min, they were transferred to a ball mill tank and ball-milled at 400 rpm for 12 h under an argon atmosphere; then the ground material was transferred to a muffle furnace and annealed at 100°C under an argon atmosphere for 6 h, and after the end of the process, the doped halide solid-state electrolyte was obtained.

[0157] Comparative Example 3

[0158] The doped halide solid-state electrolyte was Li3NbCl6.

[0159] The raw materials 80.54 mg of LiCl, 209.74 mg of ZrCl4 and 27.02 mg of NbCl5 in the expected stoichiometric ratio were uniformly mixed, and after manual grinding for 20 min, they were transferred to a ball mill tank and ball-milled at 400 rpm for 12 h under an argon atmosphere; then the ground material was transferred to a muffle furnace and annealed at 100°C under an argon atmosphere for 6 h, and after the end of the process, the doped halide solid-state electrolyte was obtained.

[0160] Comparative Example 4

[0161] The doped halide solid-state electrolyte was Li3NbCl6. 2.8 Y 0.8 Zr 0.2 Cl6.

[0162] The raw materials 80.54 mg of LiCl, 209.74 mg of ZrCl4 and 27.02 mg of NbCl5 in the expected stoichiometric ratio were uniformly mixed, and after manual grinding for 20 min, they were transferred to a ball mill tank and ball-milled at 400 rpm for 12 h under an argon atmosphere; then the ground material was transferred to a muffle furnace and annealed at 100°C under an argon atmosphere for 6 h, and after the end of the process, the doped halide solid-state electrolyte was obtained.

[0163] Example 8

[0164] The doped halide solid-state electrolyte is Li3InCl6. 2.97 In 0.8 Nb 0.12 La 0.01 Cl6.

[0165] The raw materials 125.90 mg of LiCl, 176.94 mg of InCl3, 32.42 mg of NbCl5, and 2.45 mg of LaCl3, which meet the expected stoichiometric ratio, are uniformly mixed, transferred into a ball mill jar after manual grinding for 20 min, and ball milled at 400 rpm for 12 h under an argon atmosphere; then the ground material is transferred into a muffle furnace and annealed at 100°C under an argon atmosphere for 6 h, and the doped halide solid-state electrolyte is obtained after the end of the process.

[0166] Comparative Example 5

[0167] The doped halide solid-state electrolyte is Li3InCl6.

[0168] The raw materials 127.17 mg of LiCl and 221.18 mg of InCl3, which meet the expected stoichiometric ratio, are uniformly mixed, transferred into a ball mill jar after manual grinding for 20 min, and ball milled at 400 rpm for 12 h under an argon atmosphere; then the ground material is transferred into a muffle furnace and annealed at 100°C under an argon atmosphere for 6 h, and the doped halide solid-state electrolyte is obtained after the end of the process.

[0169] Comparative Example 6

[0170] The doped halide solid-state electrolyte is Li3InCl6. 2.6 In 0.8 Nb 0.2 Cl6.

[0171] The raw materials 110.21 mg of LiCl, 176.94 mg of InCl3, and 54.03 mg of NbCl5, which meet the expected stoichiometric ratio, are uniformly mixed, transferred into a ball mill jar after manual grinding for 20 min, and ball milled at 400 rpm for 12 h under an argon atmosphere; then the ground material is transferred into a muffle furnace and annealed at 100°C under an argon atmosphere for 6 h, and the doped halide solid-state electrolyte is obtained after the end of the process.

[0172] Comparative Example 7

[0173] A commercial sulfide solid-state electrolyte Li6PS5Cl (Macklin) is used.

[0174] Testing of the doped halide solid-state electrolyte

[0175] Ion conductivity test: 100 mg of the above solid-state electrolyte was taken and added to a model battery, pressure formed and assembled into a lithium-indium symmetrical battery, and then the ion conductivity of the prepared solid-state electrolyte was tested on an autolab workstation using an alternating current impedance spectrum (EIS), and the test frequency range was 0.1 Hz to 10 6 Hz. The ion conductivity of the solid-state electrolyte was calculated according to the impedance value and the Arrhenius formula. Crystal form test: XRD test was performed on the above solid-state electrolyte powder sample using an X-ray diffractometer to qualitatively confirm whether the crystal phase of the solid-state electrolyte before and after doping changed. The test range was 10°-90°, the scanning speed was 3° / min, and the test was carried out in an argon atmosphere throughout. The test instrument was a Bruker D8 X-ray diffractometer.

[0176] XPS test was performed on the product, and after the test, Thermo Scientific TM Avantage was used to analyze and process the XPS data. The test instrument was a Thermo ESCALAB 250XI X-ray photoelectron spectrometer.

[0177] Table 1

[0178] The doped halide solid-state electrolyte prepared in Examples 1 to 6 was obtained by doping on the basis of Li2ZrCl6, the doped halide solid-state electrolyte prepared in Example 7 was obtained by doping on the basis of Li3YCl6, and the doped halide solid-state electrolyte prepared in Example 8 was obtained by doping on the basis of Li3InCl6. The diffraction peaks of the halide solid-state electrolyte before and after doping can be compared by XRD test, so it can be confirmed that the doping does not affect the phase state and space group of the original matrix material, and realizes the fine tuning on the basis of the structure of the original matrix material. By monitoring the characteristic XPS signal peaks of different elements, the element composition of the doped halide solid-state electrolyte after doping can be judged, and it is confirmed that the doping is successfully realized. After the doped halide solid-state electrolyte sample is digested with nitric acid, the element content ratio in the sample can be confirmed by ICP-OES (inductively coupled plasma emission spectrometer), and it is confirmed that the synthesis of the target metering ratio doped halide solid-state electrolyte is successfully realized.

[0179] From the above test results, it can be seen that the ion conductivity of the doped halide solid-state electrolyte prepared in the examples of the present application is obviously improved compared with the undoped halide solid-state electrolyte matrix material.

[0180] From the above test results, it can be seen that the doped halide solid-state electrolyte prepared in the examples of the present application has higher ion conductivity compared with the conventional doped doped halide solid-state electrolyte.

[0181] From the above test results, it can be seen that the doping strategy provided by the embodiments of the present application can be applied to different types of matrix doped halide solid electrolytes.

[0182] From the test results of Example 1 and Example 2, it can be seen that the C ions doped in the original matrix material, and the ion radius of the C ions is greater than the ion radius of the A ions, and greater than the ion radius of the B ions, the C ions can play a role in widening the cation interlayer spacing and weakening the lithium ion migration resistance, thereby the prepared doped halide solid electrolyte has higher ionic conductivity, and the prepared full solid-state battery has high capacity, high first coulombic efficiency and good cycle stability.

[0183] Next, the above prepared solid electrolyte is assembled into a full solid-state battery, and the effect of the solid electrolyte on the performance of the full solid-state battery is tested.

[0184] The assembly of the full solid-state battery is based on a model battery. The inner diameter of the model battery is 10 mm.

[0185] Positive electrode: LiNi 0.8 Co 0.1 Mn 0.1 O2, the above solid electrolyte, and vapor-grown carbon fiber (VGCF) in a mass ratio of 70:28:2, with a surface capacity of 3 mAh / cm 2 .

[0186] Electrolyte layer: 100 mg of commercial sulfide solid electrolyte Li6PS5Cl (Macklin).

[0187] Negative electrode: lithium-indium alloy.

[0188] Test of full solid-state battery

[0189] The test is performed on a blue cell test system. The test temperature is 25°C, and the charge and discharge voltage range is 2.6V-4.3V.

[0190] The 0.1C discharge specific capacity test method is as follows: the full solid-state battery is fully charged and discharged at a rate of 0.1C, and the ratio of the first discharge capacity to the mass of the positive electrode active material is taken as the 0.1C discharge specific capacity.

[0191] The 0.33C discharge specific capacity test method is as follows: the full solid-state battery is fully charged and discharged at a rate of 0.33C, and the ratio of the first discharge capacity to the mass of the positive electrode active material is taken as the 0.33C discharge specific capacity.

[0192] The first coulombic efficiency test method is as follows: the full solid-state battery is fully charged and discharged at a rate of 0.1C, and the ratio of the first discharge capacity to the first charge capacity is taken as the first coulombic efficiency.

[0193] The cycle performance test method is as follows: after the all-solid-state battery is cycled for three cycles at 0.1C rate, it is cycled for 200 cycles at 0.33C rate. Cycle capacity retention rate of 200 cycles = discharge capacity of 0.33C cycle 200 cycles / discharge capacity of 0.33C first cycle.

[0194] Table 2

[0195] From the above test results, it can be seen that the doped halide solid-state electrolyte prepared in the embodiments of the present application can make the all-solid-state battery have high capacity, high first coulombic efficiency and good cycle stability compared with the undoped halide solid-state electrolyte matrix material.

[0196] From the above test results, it can be seen that the doped halide solid-state electrolyte prepared in the embodiments of the present application has a higher ion conductivity improvement space compared with the conventional doped doped halide solid-state electrolyte, and thus can be better applied to all-solid-state batteries.

[0197] From the test results of Example 1 and Example 2, it can be seen that the C ion is doped and the ionic radius of the C ion is greater than the ionic radius of the A ion and greater than the ionic radius of the B ion. At this time, the C ion can play a role in widening the cation interlayer spacing and weakening the lithium ion migration resistance. Therefore, the prepared doped halide solid-state electrolyte can have higher ionic conductivity, and the prepared all-solid-state battery can have high capacity, high first coulombic efficiency and good cycle stability.

[0198] Example 2-1

[0199] The doped halide solid-state electrolyte is Li 1.97 Zr 0.8 Nb 0.16 Ce 0.01 Cl6.

[0200] The raw materials 83.51 mg of LiCl, 186.43 mg of ZrCl4, 43.22 mg of NbCl5 and 2.46 mg of CeCl3 meeting the expected stoichiometric ratio were uniformly mixed, manually ground for 20 min, and then transferred to a ball mill pot. Under an argon atmosphere, it was ball milled at 400 rpm for 6 h; then the ground material was transferred to a muffle furnace and annealed at 100°C under an argon atmosphere for 6 h. After the end, the doped halide solid-state electrolyte was obtained.

[0201] Example 2-2

[0202] The doped halide solid-state electrolyte is Li 1.97 Zr 0.8 Nb 0.16 Ce 0.01 Cl6.

[0203] The raw materials 83.51 mg of LiCl, 186.43 mg of ZrCl4, 43.22 mg of NbCl5, and 2.46 mg of CeCl3 in the expected stoichiometric ratio were uniformly mixed, and after manual grinding for 20 min, they were transferred to a ball mill tank and ball-milled at 600 rpm for 12 h under an argon atmosphere; then the ground material was transferred to a muffle furnace and annealed at 100°C under an argon atmosphere for 6 h, and after the end of the process, a doped halide solid-state electrolyte was obtained.

[0204] Example 2-3

[0205] The doped halide solid-state electrolyte was Li 1.97 Zr 0.8 Nb 0.16 Ce 0.01 Cl6.

[0206] The raw materials 83.51 mg of LiCl, 186.43 mg of ZrCl4, 43.22 mg of NbCl5, and 2.46 mg of CeCl3 in the expected stoichiometric ratio were uniformly mixed, and after manual grinding for 20 min, they were transferred to a ball mill tank and ball-milled at 200 rpm for 12 h under an argon atmosphere; then the ground material was transferred to a muffle furnace and annealed at 100°C under an argon atmosphere for 6 h, and after the end of the process, a doped halide solid-state electrolyte was obtained.

[0207] Example 2-4

[0208] The doped halide solid-state electrolyte was Li 1.97 Zr 0.8 Nb 0.16 Ce 0.01 Cl6.

[0209] The raw materials 83.51 mg of LiCl, 186.43 mg of ZrCl4, 43.22 mg of NbCl5, and 2.46 mg of CeCl3 in the expected stoichiometric ratio were uniformly mixed, and after manual grinding for 20 min, they were transferred to a ball mill tank and ball-milled at 400 rpm for 12 h under an argon atmosphere; then the ground material was transferred to a muffle furnace and annealed at 300°C under an argon atmosphere for 6 h, and after the end of the process, a doped halide solid-state electrolyte was obtained.

[0210] Example 2-5

[0211] The doped halide solid-state electrolyte was Li 1.97 Zr 0.8 Nb 0.16 Ce 0.01 Cl6.

[0212] The raw materials 83.51 mg of LiCl, 186.43 mg of ZrCl4, 43.22 mg of NbCl5 and 2.46 mg of CeCl3 in the expected stoichiometric ratio were uniformly mixed, and after manual grinding for 20 min, they were transferred to a ball mill tank and ball milled at 400 rpm for 12 h under an argon atmosphere; then the ground material was transferred to a muffle furnace and annealed at 100°C for 12 h under an argon atmosphere, and after the end of the annealing, a doped halide solid-state electrolyte was obtained.

[0213] Table 3

[0214] From the above test results, it can be seen that by further adjusting the grinding parameters and annealing parameters, the doped halide solid-state electrolyte can have a higher ionic conductivity.

[0215] It should be noted that the present application is not limited to the above embodiments. The above embodiments are only examples, and embodiments having the same technical idea and playing the same role and effect within the scope of the technical solutions of the present application are all included in the technical scope of the present application. In addition, within the scope of the main idea of the present application, various modifications of the embodiments that can be thought of by those skilled in the art, other modes constructed by combining part of the constituent elements of the embodiments are also included in the scope of the present application.

Claims

1. A doped halide solid-state electrolyte for an all-solid-state battery, wherein, The doping type halide solid-state electrolyte has a general formula of Li 6-ma-cz A a+ mx B b+ my C c+ z X6, a is a valence of A ion, b is a valence of B ion, c is a valence of C ion, a is 3 or 4, b is 4, 5 or 6, c is 2, 3, 4, 5 or 6, ax + by = a, b > a, x > y > 0, 0 ≤ z < 0.5, 0 < m < 1.5, mx + my + z < 1; A includes one or more of Ga, In, Sc, Y, lanthanide metals, Sb, Bi, Ti, Zr, Hf, B includes one or more of Ti, Zr, Hf, V, Nb, Ta, Mo, W, C includes one or more of Mg, Ca, Sr, Ba, Ga, In, Sc, Y, lanthanide metals, Sb, Bi, Ti, Zr, Hf, V, Nb, Ta, Mo, W, and A, B, C are different; X includes one or more of halogens.

2. The doped halide solid-state electrolyte of claim 1, wherein, 0<z≤0.2。 3. The doped halide solid state electrolyte of any of claims 1-2, wherein, a is 4, b is 5, and c is 2, 3, 4 or 5.

4. The doped halide solid state electrolyte of any of claims 1-2, wherein, a is 3 or 4, b is 4 or 5, and c is 2 or 3.

5. The doped halide solid state electrolyte of any one of claims 1-4, wherein, 0.5≤m≤1.25。 6. The doped halide solid state electrolyte of any one of claims 1-5, wherein, 0.5 ≤ mx < 1, and optionally, 0.8 ≤ mx < 1.

7. The doped halide solid state electrolyte of any one of claims 1-6, wherein, The ionic radius of C ion is larger than that of A ion, and the ionic radius of C ion is larger than that of B ion.

8. The doped halide solid state electrolyte of any one of claims 1-7, wherein, The doped halide solid-state electrolyte satisfies at least one of the following conditions (1) to (4): (1) A includes one or more of In, Y, Zr, lanthanide metals; (2) B includes one or more of Zr, Hf, Nb, Ta; (3) C includes one or more of Ca, In, La, Ce, Pr, Nd, Sm, Eu, Gd, Zr, Hf, Nb, Ta, Mo, and A, B, C are different; (4) X includes one or more of Cl, Br, I.

9. The doped halide solid state electrolyte of any one of claims 1-7, wherein, A includes one or more of In, Y, Zr, B includes one or more of Ti, Zr, Hf, V, Nb, Ta, and C includes one or more of Ca, La, Ce, Pr, Nd, Sm, Eu, Gd. Optionally, A includes one or more of In, Y, Zr, B includes one or more of Zr, Nb, Ta, and C includes one or more of Ca, La, Ce.

10. The doped halide solid state electrolyte of any one of claims 1-9, wherein, The doped halide solid-state electrolyte satisfies at least one of the following conditions (1) to (3): (1) The doped halide solid-state electrolyte is any one of a glass phase, a glass-ceramic phase, and a crystalline phase; (2) The doped halide solid-state electrolyte has a volume distribution particle size Dv50 of 0.5 μm-10 μm; (3) The doped halide solid-state electrolyte has an ionic conductivity of 0.5 mS / cm-15 mS / cm at 25°C. 11.A method for preparing a doped halide solid-state electrolyte, comprising the steps of: mixing halides of elements Li, A, B, and optionally C in a proportion, and then performing grinding under a protective gas atmosphere, and then performing annealing of the ground material under a protective gas atmosphere to obtain a doped halide solid-state electrolyte, The doping type halide solid-state electrolyte has a general formula of Li 6-ma-cz A a+ mx B b+ my C c+ z X6, a is the valence of the A ion, b is the valence of the B ion, c is the valence of the C ion, a is 3 or 4, b is 4, 5 or 6, c is 2, 3, 4, 5 or 6, ax+by=a, b>a, x>y>0, 0 A comprises one or more of Ga, In, Sc, Y, lanthanide metals, Sb, Bi, Ti, Zr, Hf, B comprises one or more of Ti, Zr, Hf, V, Nb, Ta, Mo, W, C comprises one or more of Mg, Ca, Sr, Ba, Ga, In, Sc, Y, lanthanide metals, Sb, Bi, Ti, Zr, Hf, V, Nb, Ta, Mo, W, and A, B, C are different; X comprises one or more of halogens.

12. The method of making according to claim 11, wherein, The preparation method satisfies at least one of the following conditions (1) to (4): (1) the rotation speed of the grinding is 300 rpm-600 rpm; (2) the grinding time is 6h-72h; (3) the annealing temperature is 100℃-300℃; (4) the annealing time is 2h-24h.

13. The method of making according to any one of claims 11-12, wherein, The preparation method satisfies at least one of the following conditions (1) to (4): (1) the rotation speed of the grinding is 400 rpm-550 rpm; (2) the grinding time is 12h-48h; (3) the annealing temperature is 100℃-200℃; (4) the annealing time is 5h-12h.

14. An all-solid-state battery comprising a positive electrode, wherein the positive electrode comprises a positive electrode active material and the doped halide solid-state electrolyte of any one of claims 1-10 or prepared by the preparation method of any one of claims 11-13.

15. The all-solid-state battery according to claim 14, wherein The mass ratio of the positive electrode active material to the doped halide solid-state electrolyte is 90:10 to 70:

30.

16. The all-solid-state battery according to any one of claims 14-15, wherein, The positive electrode active material comprises one or more of lithium cobaltate and modified materials thereof, lithium iron phosphate and modified materials thereof, lithium iron manganese phosphate and modified materials thereof, lithium nickel cobalt manganese oxide and modified materials thereof, lithium nickel cobalt aluminum oxide and modified materials thereof, lithium nickel oxide and modified materials thereof, lithium manganese oxide and modified materials thereof, lithium titanate, sulfur, selenium, tellurium.

17. The all-solid-state battery according to any one of claims 14-16, wherein, The all-solid-state battery further comprises a negative electrode and an electrolyte layer, the electrolyte layer is located between the positive electrode and the negative electrode, and the negative electrode comprises one or more of graphite, graphene, carbon nanotubes, mesocarbon microbeads, soft carbon, hard carbon, silicon-based materials, tin-based materials, lithium titanate, metal oxides, metallic lithium, lithium alloys, lithium composite materials.

18. An electrical device, comprising: The all-solid-state battery comprises the all-solid-state battery of any one of claims 14-17.

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