Sulfide solid electrolyte and preparation method thereof, solid electrolyte membrane, electrode plate, solid-state battery and electric device

Abstract

The invention relates to a sulfide solid electrolyte and a preparation method thereof, a solid electrolyte membrane, an electrode plate, a solid-state battery and an electric device. The sulfide solid electrolyte comprises an LGPS type crystal phase; the LGPS type crystal phase comprises a Li element, a Sn element, a P element and an S element, the atomic number ratio of the Sn element to the S element is larger than 1 / 12, and the atomic number ratio of the Sn element to the P element is larger than 1 / 2. According to the sulfide solid electrolyte, the hydrogen sulfide release amount of the sulfide electrolyte in a water-containing environment can be reduced under the condition that relatively good ionic conductivity is maintained.

Description

Technical Field

[0001] The present application relates to the field of secondary battery technology, further to the field of solid-state battery technology, and further to sulfide solid electrolytes and preparation methods thereof, solid electrolyte membranes, electrode plates, solid-state batteries and electrical devices. Background Art

[0002] The statements herein merely provide background information related to the present application and do not necessarily constitute prior art.

[0003] Solid-state batteries introduce non-flammable solid electrolytes to replace the organic electrolytes in traditional liquid secondary batteries, significantly improving battery safety. Among the numerous solid electrolyte materials, sulfide solid electrolytes, due to their ultra-high ionic conductivity and excellent mechanical properties, have become the most practical and industrially viable solid electrolyte material. However, sulfide solid electrolytes have poor stability and readily react with moisture in the air, releasing the highly toxic gas hydrogen sulfide, severely restricting their practical application. Summary of the Invention

[0004] In view of the above problems, according to various embodiments and examples of the present application, the present application provides a sulfide solid electrolyte and its preparation method, solid electrolyte membrane, electrode plate, solid-state battery, and electrical device. The sulfide solid electrolyte significantly reduces the amount of hydrogen sulfide released by the sulfide electrolyte in an aqueous environment.

[0005] In a first aspect of the present application, there is provided a sulfide solid electrolyte comprising an LGPS type crystal phase;

[0006] The LGPS type crystal phase includes Li, Sn, P and S elements, wherein the atomic number ratio of Sn to S is greater than 1 / 12, and the atomic number ratio of Sn to P is greater than 1 / 2;

[0007] The LGPS type crystal phase includes or excludes cationic substitution elements, and also includes or excludes anionic substitution elements;

[0008] When the LGPS type crystal phase includes a cationic substitution element, the cationic substitution element includes Sb element;

[0009] When the LGPS type crystal phase includes an anion substitution element, the anion substitution element includes at least one of an O element and a Cl element.

[0010] This sulfide solid electrolyte includes an LGPS-type crystal phase. By controlling the atomic ratio of tin (Sn) to sulfur (S) to be greater than 1 / 12 (one-twelfth) and the atomic ratio of Sn to P to be greater than 1 / 2 (one-half), the phosphorus (P) content can be reduced. Based on the hard soft acid base (HASB) theory, compared to the bond strength between hard acid (P) and soft base (S), soft acid (Sn) and soft base (S) can form a stronger chemical bond. This stronger chemical bond is not easily destroyed by water molecules, which can significantly reduce the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in aqueous environments (such as air).

[0011] The sulfide solid electrolyte can further reduce the amount of hydrogen sulfide gas released by one or both of cation substitution and anion substitution. On the one hand, cation substitution can be used to increase the content of either Sn element or Sb element in the material structure, which can reduce the P element content. Based on the hard and soft acid-base theory, compared with the bond strength between hard acid (P) and soft base (S), soft acid (Sn or Sb) and soft base (S) have stronger chemical bonds. This stronger chemical bond is not easily destroyed by water molecules, which can reduce the amount of hydrogen sulfide gas released by the sulfide electrolyte in an aqueous environment. On the other hand, anion substitution can be used to replace the S element by any one of the O element and Cl element, which can reduce the S element content in the material structure and reduce the amount of hydrogen sulfide gas released. Cationic substitution and anionic substitution can be combined to better reduce the amount of hydrogen sulfide gas released.

[0012] In some embodiments, the LGPS type crystalline phase satisfies one or more of the following characteristics:

[0013] In the LGPS type crystal phase, the atomic ratio of the cationic substitution element and the P element is recorded as R Y / P , 0≤R Y / P ≤4 / 9, optionally, 0 <R Y / P ≤4 / 9, further optionally, 2 / 14≤R Y / P ≤3 / 11;

[0014] In the LGPS type crystal phase, the atomic ratio of the anion substitution element and the S element is recorded as R N / S , 0≤R N / S ≤34 / 86, optionally, 0 <R N / S ≤34 / 86, further optionally, 18 / 102≤R N / S ≤29 / 91.

[0015] By the ratio of the number of atoms of the cation substituent element and the P element (R Y / P ), the atomic number ratio of the anion substitution element and the S element (R N / S) is controlled within the aforementioned range, which is more conducive to maintaining good ionic conductivity while reducing the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in an aqueous environment.

[0016] In some embodiments, the LGPS type crystalline phase satisfies one or more of the following characteristics:

[0017] The atomic number ratio of Sn element to S element is greater than or equal to 11 / 120;

[0018] The atomic number ratio of the Sn element to the S element is less than or equal to 17 / 86, optionally, greater than or equal to 14 / 120 and less than or equal to 16 / 91;

[0019] The atomic number ratio of Sn element to P element is greater than or equal to 11 / 19;

[0020] The atomic number ratio of the Sn element to the P element is less than or equal to 17 / 9, and optionally, greater than or equal to 14 / 16 and less than or equal to 16 / 10.

[0021] By controlling at least one parameter of the atomic number ratio of Sn element to S element and the atomic number ratio of Sn element to P element within the aforementioned range, while reducing the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in an aqueous environment, it is also more conducive to maintaining good ionic conductivity.

[0022] In some embodiments, the LGPS type crystal phase includes Sb element;

[0023] Optionally, the atomic number ratio of the Sb element to the S element is greater than 0 and less than or equal to 4 / 86, and further optionally, greater than or equal to 2 / 120 and less than or equal to 3 / 91;

[0024] Optionally, the atomic number ratio of the Sb element to the P element is greater than 0 and less than or equal to 4 / 9, and further optionally, greater than or equal to 2 / 14 and less than or equal to 3 / 11;

[0025] Optionally, the atomic number ratio of the sum of the Sn element and the Sb element to the S element is greater than 1 / 12 and less than or equal to 21 / 86, further optionally, greater than or equal to 11 / 120 and less than or equal to 21 / 86, and further optionally, greater than or equal to 16 / 120 and less than or equal to 19 / 91;

[0026] Optionally, the atomic number ratio of the sum of Sn element and Sb element to P element is greater than 1 / 2 and less than or equal to 21 / 9, further optionally, greater than or equal to 11 / 19 and less than or equal to 21 / 9, and further optionally, greater than or equal to 16 / 14 and less than or equal to 19 / 11.

[0027] By doping antimony (Sb) into the LGPS type crystal phase, Sb can replace part of the P element, further reducing the P element content; based on the hard and soft acid-base theory, compared with the bonding strength between hard acid (P) and soft base (S), soft acid (Sb) and soft base (S) also have stronger chemical bonds, which are not easily destroyed by water molecules, and can further reduce the amount of hydrogen sulfide gas released by sulfide solid electrolytes in aqueous environments.

[0028] By controlling at least one parameter among the atomic moles of Sb element and S element, the atomic number ratio of the sum of Sn element and Sb element to S element, and the atomic number ratio of the sum of Sn element and Sb element to P element within the aforementioned range, it is beneficial to reduce the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in an aqueous environment while maintaining good ionic conductivity.

[0029] In some embodiments, the LGPS type crystal phase includes at least one of an O element and a Cl element;

[0030] Optionally, the LGPS type crystal phase includes O element, and further optionally, the atomic number ratio of O element to S element is greater than 0 and less than or equal to 29 / 86;

[0031] Optionally, the atomic number ratio of the O element to the S element is greater than or equal to 0 and less than or equal to 29 / 86, and further optionally, greater than or equal to 15 / 105 and less than or equal to 20 / 91;

[0032] Optionally, the LGPS type crystal phase includes Cl element, and further optionally, the atomic number ratio of Cl element to S element is greater than 0 and less than or equal to 5 / 86;

[0033] Optionally, the atomic number ratio of the Cl element to the S element is greater than or equal to 0 and less than or equal to 5 / 86, and further optionally, greater than or equal to 3 / 117 and less than or equal to 4 / 91.

[0034] By doping oxygen (O) elements into the LGPS type crystal phase, the O elements can replace part of the S elements, which is beneficial to further reduce the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in an aqueous environment.

[0035] By doping chlorine (Cl) element into the LGPS type crystal phase, the Cl) element can replace part of the S element, which is beneficial to further reduce the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in an aqueous environment.

[0036] By controlling at least one parameter of the atomic number ratio of the O element to the S element and the atomic number ratio of the Cl element to the S element within the aforementioned range, it is beneficial to reduce the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in an aqueous environment while maintaining good ionic conductivity.

[0037] In some embodiments, the LGPS type crystal phase includes or excludes Sb element, includes or excludes O element, and includes or excludes Cl element;

[0038] The atomic number ratio of Li, Sn, P, Sb, S, O and Cl is (10+xm):(1+x):(2-xy):y:(12-zm):z:m; <x≤0.7,0≤y≤0.4,0≤z≤2.9,0≤m≤0.5。

[0039] In some embodiments, the chemical formula of the LGPS type crystal phase is Li 10+x-m Sn 1+x P 2-x-y Sb y S 12-z-m O z Cl m .

[0040] In some embodiments, the LGPS type crystalline phase satisfies one or more of the following characteristics:

[0041] (z+m)>0, optionally, 0<(z+m)≤3.4, further optionally, 1.8≤(z+m)≤3.4;

[0042] 0.1≤x≤0.7, optionally, 0.4≤x≤0.6;

[0043] 0.2≤y≤0.4, optionally, 0.2≤y≤0.3;

[0044] 1.5≤z≤2.9, optionally, 1.5≤z≤2.5;

[0045] 0.3≤m≤0.5, optionally, 0.3≤m≤0.4.

[0046] By controlling the content of Sn element and the doping amount of Sb element, O element and Cl element in the LGPS type crystal phase within the aforementioned range, the Sn element can be used to reduce the P element content, the Sb element can be selectively used (or not) to reduce the P element content, the O element can be selectively used to replace the S element, and the Cl element can be selectively used to replace the S element. Among them, on the one hand, cation substitution can be used to increase the content of either Sn element or Sb element in the material structure, which can reduce the P element content. Based on the hard and soft acid-base theory, compared with the bond strength between hard acid (P) and soft base (S), soft acid (Sn or Sb) and soft base (S) have stronger chemical bonds. This stronger chemical bond is not easily destroyed by water molecules, which can reduce the amount of hydrogen sulfide gas released by the sulfide electrolyte in an aqueous environment. On the other hand, anion substitution can be used to replace the S element by any one of the O element and Cl element, which can reduce the S element content in the material structure and reduce the amount of hydrogen sulfide gas released.

[0047] When cation substitution and anion substitution are performed simultaneously, (z+m)>0, which can more effectively reduce the amount of hydrogen sulfide gas released.

[0048] In addition, by controlling one or more parameters among x, y, z and m within the aforementioned range, it is advantageous to reduce the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in an aqueous environment while maintaining good ionic conductivity.

[0049] In some embodiments, the LGPS type crystalline phase satisfies one, any two, or three of the following characteristics:

[0050] y=0;

[0051] z = 0;

[0052] m=0.

[0053] When y=0, the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in an aqueous environment can be reduced without introducing the Sb element.

[0054] When z=0, the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in an aqueous environment can be reduced without O element doping.

[0055] When m=0, the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in an aqueous environment can be reduced without Cl element doping.

[0056] In some embodiments, y=0, z=0, and m=0.

[0057] When y = 0, z = 0, and m = 0, the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in an aqueous environment can be reduced by controlling the atomic quantity ratio of Sn elements.

[0058] In some embodiments, 0 < y ≤ 0.4, z = 0, and m = 0.

[0059] When 0 < y ≤ 0.4, z = 0, and m = 0, based on the aforementioned cation substitution method, while reducing the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in an aqueous environment, good ionic conductivity can still be maintained.

[0060] In some embodiments, y = 0, 0 < z ≤ 2.9, and m = 0.

[0061] When y = 0, 0 < z ≤ 2.9, and m = 0, based on O element doping, while reducing the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in an aqueous environment, good ionic conductivity can still be maintained.

[0062] In some embodiments, y = 0, z = 0, and 0 < m ≤ 0.5.

[0063] When y = 0, z = 0, and 0 < m ≤ 0.5, based on Cl element doping, while reducing the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in an aqueous environment, good ionic conductivity can still be maintained.

[0064] In some embodiments, the LGPS-type crystal phase includes one or more of the compounds represented by the following chemical formulas: Li 10.5 Sn 1.5 P 1.5 S 12 、Li 10.5 Sn 1.5 P 1.3 Sb 0.2 S 12 、Li 10.5 Sn 1.5 P 1.5 S 10.5 O 1.5 、Li 10.2 Sn 1.5 P 1.5 S 11.7 Cl 0.3 、Li 10.5 Sn 1.5 P 1.3 Sb 0.2 S 10.5 O 1.5 、Li 10.2 Sn 1.5 P 1.3 Sb 0.2 S 11.7 Cl0.3 He Li 10.2 Sn 1.5 P 1.5 S 10.2 O 1.5 Cl 0.3 .

[0065] By providing one or more of the aforementioned LGPS-type sulfide electrolytes in the sulfide solid electrolyte, it is more advantageous to achieve both reduced hydrogen sulfide gas release and better ionic conductivity.

[0066] In some embodiments, the 2θ (°) diffraction angle in the X-ray diffraction pattern of the sulfide solid electrolyte has a characteristic peak consistent with the LGPS type crystal phase.

[0067] In some embodiments, the X-ray diffraction pattern of the sulfide solid electrolyte satisfies at least one of the following characteristics:

[0068] The 2θ (°) diffraction angle in the X-ray diffraction pattern of the sulfide solid electrolyte has peaks at 14.6±δ°, 17.4±δ°, 20.2±δ°, 20.5±δ°, 24.0±δ°, 26.9±δ°, 29.5±δ°, 32.6±δ°, 36.5±δ°, 41.5±δ° and 47.3±δ°, wherein δ is 0.2 or 0.1;

[0069] The X-ray diffraction pattern of the sulfide solid electrolyte is obtained by using Cu Kα radiation;

[0070] The X-ray diffraction pattern of the sulfide solid electrolyte is obtained by powder X-ray diffraction testing.

[0071] The chemical composition of the sulfide solid electrolyte can be confirmed by X-ray diffraction (XRD) detection.

[0072] In a second aspect of the present application, a method for preparing a sulfide solid electrolyte is provided, which can be used to prepare the sulfide solid electrolyte described in the first aspect of the present application.

[0073] In some embodiments, the method for preparing the sulfide solid electrolyte comprises the following steps:

[0074] A precursor mixture including Li2S, P2S5, SnS2 and elemental sulfur is provided according to a required raw material stoichiometric ratio, wherein the precursor mixture includes or does not include a cation source, and the precursor mixture includes or does not include an anion source; wherein the cation source is a raw material for providing a cation-substituting element, and the anion source is a raw material for providing an anion-substituting element; when the sulfide solid electrolyte includes a cation-substituting element, the cation-substituting element includes Sb; when the sulfide solid electrolyte includes an anion-substituting element, the anion-substituting element includes at least one of O and Cl; when the sulfide solid electrolyte contains Sb, the precursor mixture includes Sb2S3; when the sulfide solid electrolyte contains O, the precursor mixture includes P2O5; when the sulfide solid electrolyte contains Cl, the precursor mixture includes LiCl;

[0075] The precursor mixture is sintered in an inert atmosphere to prepare a sulfide solid electrolyte including an LGPS type crystal phase; in the LGPS type crystal phase, the atomic number ratio of the Sn element to the S element is greater than 1 / 12, and the atomic number ratio of the Sn element to the P element is greater than 1 / 2.

[0076] In some embodiments, the method for preparing the sulfide solid electrolyte satisfies one or more of the following characteristics:

[0077] The weight percentage of the sulfur element relative to the precursor mixture is 2.9 wt% to 3.1 wt%;

[0078] The inert atmosphere is an argon atmosphere;

[0079] In the step of sintering the precursor mixture in an inert atmosphere, the sintering temperature is 520° C. to 620° C., and can be 530° C. to 620° C.;

[0080] The prepared sulfide solid electrolyte is the sulfide solid electrolyte described in the first aspect of the present application.

[0081] The sulfide solid electrolyte described in the first aspect of the present application can be obtained by sintering a corresponding precursor mixture at a certain sintering temperature in the presence of excess sulfur.

[0082] In a third aspect of the present application, a solid electrolyte membrane is provided, comprising at least one of the sulfide solid electrolyte described in the first aspect of the present application and the sulfide solid electrolyte prepared by the preparation method described in the second aspect of the present application.

[0083] For the solid electrolyte membrane provided with the aforementioned sulfide solid electrolyte, the sulfide solid electrolyte has high stability in an aqueous environment (such as air), low hydrogen sulfide release, and good chemical stability of the material, so that the sulfide solid electrolyte in the solid electrolyte membrane has good quality stability, which is conducive to enabling the corresponding solid-state battery to fully utilize the high ionic conductivity advantage of the sulfide solid electrolyte and have good cycle performance.

[0084] In a fourth aspect of the present application, an electrode plate is provided, which includes an electrode active material layer, wherein the electrode active material layer includes an electrode active substance, and also includes at least one of the sulfide solid electrolyte described in the first aspect of the present application and the sulfide solid electrolyte prepared by the preparation method described in the second aspect of the present application.

[0085] In some embodiments, the electrode plate is a positive electrode plate, the electrode active material layer is referred to as a positive electrode active material layer, and the electrode active substance is referred to as a positive electrode active substance;

[0086] Alternatively, the electrode plate is a negative electrode plate, the electrode active material layer is recorded as a negative electrode active material layer, and the electrode active substance is recorded as a negative electrode active substance.

[0087] For the electrode plates provided with the aforementioned sulfide solid electrolyte, the sulfide solid electrolyte has high stability in an aqueous environment (such as air), low hydrogen sulfide release, and good chemical stability of the material, so that the electrode plates have good quality stability. The solid-state battery assembled using the electrode plates can give full play to the high ionic conductivity advantage of the sulfide solid electrolyte and have good cycle performance.

[0088] The electrode plate can be a positive electrode plate or a negative electrode plate.

[0089] In the fifth aspect of the present application, a solid-state battery is provided, which includes the sulfide solid electrolyte described in the first aspect of the present application, the sulfide solid electrolyte prepared by the preparation method described in the second aspect of the present application, the solid electrolyte membrane described in the third aspect of the present application, and at least one of the electrode pole pieces described in the fourth aspect of the present application.

[0090] In some embodiments, the solid-state battery is a sulfide all-solid-state battery.

[0091] For a solid-state battery provided with the aforementioned sulfide solid electrolyte, the sulfide solid electrolyte may be provided at one or more of the positive electrode layer, the negative electrode layer, and the solid electrolyte layer.

[0092] In the sixth aspect of the present application, an electrical device is provided, which includes at least one of the sulfide solid electrolyte described in the first aspect of the present application, the sulfide solid electrolyte prepared by the preparation method described in the second aspect of the present application, the solid electrolyte membrane described in the third aspect of the present application, the electrode plate described in the fourth aspect of the present application, and the solid-state battery described in the fifth aspect of the present application.

[0093] The details of one or more embodiments or examples of the present application are set forth in the following drawings and description. Other features, objects, and advantages of the present application will become apparent from the description, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0094] In order to better describe and illustrate the embodiments, examples or examples provided in this application, reference may be made to one or more of the accompanying drawings. The additional details or examples used to describe the accompanying drawings should not be considered as limiting the scope of the disclosed application, the embodiments, examples or examples currently described, and any of the best modes of these applications currently understood. It should also be noted that the accompanying drawings are drawn in a simplified form and are only used to assist in the explanation of this application for convenience and clarity. The various dimensions of each component shown in the accompanying drawings are arbitrarily shown and may be accurate or not drawn to scale. For example, in order to make the illustration clearer, the dimensions of the components are appropriately exaggerated in some places in the accompanying drawings. Unless otherwise specified, the components in the drawings are not drawn to scale. The drawings of this application do not limit every dimension of each component. Moreover, the same figure numbers are used to represent the same components in all the drawings. In the drawings:

[0095] Figure 1 This is a schematic structural diagram of a solid-state battery cell according to one embodiment of the present application, which includes a positive electrode layer, a solid electrolyte layer, and a negative electrode layer stacked in sequence.

[0096] Figure 2 Schematic diagram of a solid-state battery cell according to one embodiment of the present application.

[0097] Figure 3 for Figure 2 An exploded view of a solid-state battery cell according to an embodiment of the present application is shown.

[0098] Figure 4 This is a schematic diagram of a battery module according to one embodiment of the present application.

[0099] Figure 5 Schematic diagram of a battery pack according to one embodiment of the present application.

[0100] Figure 6 for Figure 5 An exploded view of a battery pack according to an embodiment of the present application is shown.

[0101] Figure 7Schematic diagram of an electrical device using a solid-state battery as a power source according to one embodiment of the present application.

[0102] Figure 8 The X-ray diffraction (XRD) diagrams of the sulfide solid electrolytes prepared in Preparation Example 1 and Comparative Example 1 in this application are shown, where the abscissa axis represents 2θ (°) and the ordinate represents intensity.

[0103] Explanation of the accompanying drawings: 100, solid electrolyte layer; 200, positive electrode layer; 300, negative electrode layer; 1, battery pack; 2, upper case; 3, lower case; 4, battery module; 5, solid-state battery cell; 51, shell; 52, solid-state battery cell; 53, cover plate; 6, electrical device. DETAILED DESCRIPTION

[0104] Below, some embodiments of the sulfide solid electrolyte and its preparation method, solid electrolyte membrane, electrode plate, solid-state battery, electrical device, etc. provided by the present application are described in detail with appropriate reference to the accompanying drawings. However, there may be cases where unnecessary detailed descriptions are omitted. For example, there are cases where detailed descriptions of well-known matters and repeated descriptions of actually the same structure are omitted. This is to avoid the following description from becoming unnecessarily lengthy and to facilitate the understanding of those skilled in the art. In addition, the drawings and the following description are provided for those skilled in the art to fully understand the present application and are not intended to limit the subject matter described in the claims.

[0105] " scope " disclosed in the present application can be limited in the form of lower limit and upper limit, and given range is limited by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundary of special range. The scope limited in this way can be to include end value or not include end value, and any end value can be included or not included independently, and can be arbitrarily combined, that is, any lower limit can form a scope with any upper limit combination. For example, if the scope of 60-120 and 80-110 is listed for specific parameters, it is understood that the scope of 60-110 and 80-120 is also expected. In addition, if minimum range values ​​1 and 2 are listed, and if maximum range values ​​3,4 and 5 are also listed, then the following scope can all be expected: 1-3, 1-4, 1-5, 2-3, 2-4 and 2-5. In the present application, unless otherwise specified, numerical range " ab " represents the abbreviation of any real number combination between a and b, wherein a and b are all real numbers. For example, the numerical range "0-5" indicates that all real numbers between "0-5" are listed herein, and "0-5" is merely an abbreviation for these numerical combinations. Furthermore, when a parameter is expressed as an integer ≥ 2, this is equivalent to listing the parameter as, for example, the integers 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, and so on. For example, when a parameter is expressed as an integer selected from "2-10", this is equivalent to listing the integers 2, 3, 4, 5, 6, 7, 8, 9, and 10.

[0106] In this application, unless otherwise specified, "about" means within a reasonable range above or below the number. The fluctuation range may vary depending on the type and value of the number. For example, a range of ±10%, ±5%, ±2%, ±1%, etc. may be allowed. For example, taking "about 20°C" and its approximate value of ±1°C as an example, approximate values ​​such as 19°C and 19.5°C within the approximate range of "about 20°C" should also be included in the range indicated by "about 20°C".

[0107] In this application, references to "multiple," "multiple," "multiple," "several," and the like, unless otherwise specified, refer to a quantity greater than or equal to two. For example, "one or more" means one or ≥ (greater than or equal to) two. It is understood that references to "any number" of items refer to any suitable combination of multiple items, i.e., any combination of "any number" of items that is not in conflict and that enables the implementation of this application.

[0108] Unless otherwise specified, all embodiments and optional embodiments of the present application can be combined with each other to form a new technical solution.

[0109] References to "embodiments" herein mean that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment or implementation of the present application. The appearance of such phrases in various locations in the specification does not necessarily refer to the same embodiment, nor does it necessarily refer to independent or alternative embodiments that are mutually exclusive with other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments. References to "implementations" herein have a similar understanding.

[0110] Those skilled in the art will appreciate that, in the methods of each embodiment or embodiment, the order in which each step is written does not mean a strict order of execution and constitutes any limitation to the implementation process, and the detailed order of execution of each step should be determined by its function and possible inherent logic. Unless otherwise specified, all steps of the present application can be performed in sequence, or can be performed randomly, or can preferably be performed in sequence. For example, method M includes steps (a) and (b), indicating that the method may include steps (a) and (b) performed in sequence, or steps (b) and (a) performed in sequence. For example, method M may also include step (c), indicating that step (c) can be added to method M in any order, for example, method M may include steps (a), (b) and (c), or steps (a), (c) and (b), or steps (c), (a) and (b), etc.

[0111] In this application, in open technical features or technical solutions described with words such as "contain," "include," and "include," unless otherwise specified, additional members other than the listed members are not excluded, and it can be regarded as providing both closed features or solutions consisting of the listed members and open features or solutions including additional members in addition to the listed members. For example, A includes a1, a2, and a3. Unless otherwise specified, it may also include other members or not. It can be regarded as providing both the feature or solution of "A consists of a1, a2, and a3" or "A is selected from a1, a2, and a3", and the feature or solution of "A includes not only a1, a2, and a3, but also other members."

[0112] In this application, unless otherwise specified, A (such as B) means that B is a non-limiting example of A, and it can be understood that A is not limited to B.

[0113] In this application, "optionally," "optional," and "optional" mean optional, that is, any one of the two parallel options of "yes" or "no." If multiple "options" appear in a technical solution, unless otherwise specified and there are no contradictions or mutual constraints, each "optional" is independent. Unless otherwise specified, the descriptions "optionally include," "optionally include," etc. in this application, using "optionally include" as an example, mean "may include or not include."

[0114] In this application, unless otherwise specified, the features or solutions corresponding to "and / or" include any one of two or more relevant listed items, and also include any and all combinations of the relevant listed items, wherein any and all combinations include any two relevant listed items, any more relevant listed items, or a combination of all relevant listed items. For example, "A and / or B" means a group consisting of A, B, and "a combination of A and B." Among them, "including A and / or B" can mean "including A, including B, and including A and B", and can also mean "including A, including B, or including A and B", which can be appropriately understood according to the sentence in which it is used.

[0115] As used herein, "combination thereof", "any combination thereof", "any combination thereof" and the like include all suitable combinations of any two or more of the listed items.

[0116] Herein, the word “suitable” in “suitable combination”, “suitable method”, “any suitable method”, etc., shall be based on the technical solution that can implement the present application.

[0117] Herein, the terms "preferred," "better," "more preferable," "suitable," "comparatively better," and "preferable" are used solely to describe preferred implementations or examples and should not be construed as limiting the scope of protection of this application. If multiple "preferred" terms appear in a technical solution, each "preferred" term is considered independent unless otherwise specified and there are no contradictions or mutual constraints.

[0118] In this application, "further", "further", "particularly", "for example", "such as", "example", "for example", etc. are used for descriptive purposes to indicate differences in content, but should not be understood as limiting the scope of protection of this application.

[0119] In this application, the terms "first", "second", "third", "fourth", "fifth", "sixth", etc. in "first aspect", "second aspect", "third", "fourth", "fifth", "sixth", etc. are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or quantity, nor can they be understood as implicitly indicating the importance or quantity of the indicated technical features. Moreover, "first", "second", "third", "fourth", "fifth", "sixth", etc. only serve the purpose of non-exhaustive enumeration and description, and it should be understood that they do not constitute a closed limitation on quantity.

[0120] In this application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. In this application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may refer to a relative horizontal positional relationship, or may simply refer to an attachment relationship without limiting the relative horizontal positional relationship.

[0121] In this application, the term "room temperature" generally refers to 4°C to 35°C, and may refer to 20°C ± 5°C. In some embodiments or examples of this application, room temperature refers to 20°C to 30°C.

[0122] In this application, when referring to a data range, if the unit is followed only by the right endpoint, it means that the units of the left and right endpoints are the same. For example, "3~5h" or "3-5h" both mean that the units of the left endpoint "3" and the right endpoint "5" are both hours, and both have the same meaning as "3h~5h". Similarly, descriptions of other parameters such as temperature and size are to be understood in the same manner.

[0123] The weight or mass of the relevant components mentioned in the embodiments or examples of the present application can not only refer to the content of each component, but also represent the proportional relationship of weight or mass between each component. Therefore, as long as the content of the relevant components in accordance with the embodiments or examples of the present application is proportionally enlarged or reduced, it is within the scope described in the present application. Further, the mass involved in the embodiments or examples of the present application can be mass units known to the chemical industry such as micrograms (μg), milligrams (mg), grams (g), kilograms (kg). Unless otherwise specified, the mass ratio is equal to the corresponding weight ratio, such as the mass of substance A is m1 and the weight is W1, the mass of substance B is m2 and the weight is W2, then the mass ratio m1 / m2 of the two is numerically equal to the corresponding weight ratio W1 / W2.

[0124] In this application, unless otherwise specified, wt% represents weight percentage by weight and is numerically equivalent to the corresponding mass percentage by mass. In this application, when a weight percentage is represented by "0", it has the same meaning as "0wt%" and can be used interchangeably.

[0125] The units of parameters involved in this application, unless otherwise specified, are nm for nanometers, μm for micrometers, S / cm for Siemens per centimeter, V for volts, kV for kilovolts, mA for milliamperes, Hz for Hertz, mPa·S for millipascals·seconds, and mg / cm 2 Expressed in milligrams per square centimeter, g / cm 2 Indicates grams per square centimeter, g / cm 3 represents grams per cubic centimeter and ℃ represents degrees Celsius.

[0126] In this application, "greater than or equal to", "greater than or equal to", and "≥" have the same meaning and can be used interchangeably; "less than or equal to", "less than or equal to", and "≤" have the same meaning and can be used interchangeably; "greater than" can be equivalently expressed as ">", and "less than" can be equivalently expressed as "<". In this application, unless otherwise specified, "greater than or equal to" and "≥" can be regarded as providing two solutions of "greater than" and "equal to". In this application, unless otherwise specified, "less than or equal to" and "≤" can be regarded as providing two solutions of "less than" and "equal to".

[0127] In this application, exemplary descriptions such as "in some embodiments (or examples)" and "in one embodiment (or example)" may include but are not limited to the following meanings: these solutions can be combined with other solutions in a suitable manner to form new technical solutions.

[0128] In this application, unless otherwise specified, the "solid-state battery" provided in this application refers to a battery in which the electrolyte in the battery includes a solid electrolyte; generally, a solid-state battery includes a positive electrode layer, a solid electrolyte layer and a negative electrode layer. During the charge and discharge process of the battery, active ions are embedded and released back and forth between the positive electrode layer and the negative electrode layer. The solid electrolyte layer plays the role of conducting ions between the positive electrode layer and the negative electrode layer, and can also isolate the positive electrode layer from the negative electrode layer to prevent the positive and negative electrodes from short-circuiting. Therefore, the isolation membrane in the traditional lithium-ion battery can be omitted in the solid-state battery. The solid-state battery introduces a non-flammable solid electrolyte to replace the organic electrolyte in the traditional liquid lithium-ion battery, which greatly improves the safety of the battery. In addition to improving safety, solid-state batteries can better adapt to high-energy-density positive and negative electrode materials and reduce the weight of the system, which is conducive to taking into account the improvement of energy density.

[0129] In this application, unless otherwise specified, "solid electrolyte" refers to an electrolyte material or substance that exists in a solid form during the storage and preparation of a solid-state battery and its components, as well as during the operation of the solid-state battery. It is understood that the solid electrolyte exists in a solid form, including but not limited to, at room temperature.

[0130] In this application, unless otherwise specified, an electrode layer may be a positive electrode layer or a negative electrode layer, and the electrode layer includes an electrode active material. The electrode active material may be a positive electrode active material or a negative electrode active material. The electrode active material may be a particle itself or contained in electrode active particles. The electrode active particles may be positive electrode active particles or negative electrode active particles. The "electrode active material" in the electrode layer refers to a substance capable of reversibly inserting and removing active ions. Unless otherwise specified, "negative electrode active material" refers to a substance used in the negative electrode layer that is capable of reversibly inserting and removing active ions; "positive electrode active material" refers to a substance used in the positive electrode layer that is capable of reversibly removing and inserting active ions. When a solid-state battery is charging, active ions are removed from the positive electrode and inserted into the negative electrode through the solid electrolyte layer; when the solid-state battery is discharging, active ions are removed from the negative electrode and inserted into the positive electrode. The active ions are not particularly limited and are non-restrictive. The active ions can be lithium ions, in which case the battery corresponds to a lithium-ion solid-state battery.

[0131] In the present application, "electrode active particles" refer to particles containing an electrode active material.

[0132] In this application, "electrode active material", "electrode active substance", "active material" and "active substance" have the same meaning and can be used interchangeably; "positive electrode active substance" and "positive electrode active material" have the same meaning and can be used interchangeably; "negative electrode active substance" and "negative electrode active material" have the same meaning and can be used interchangeably. "Positive electrode active substance" and "positive electrode active material" have the same meaning and can be used interchangeably; "negative electrode active substance" and "negative electrode active material" have the same meaning and can be used interchangeably.

[0133] In this application, unless otherwise specified, the term "electrode active material layer" includes at least one of the positive electrode active material layer in the positive electrode layer and the negative electrode active material layer in the negative electrode layer. Depending on the specific circumstances, the electrode active material layer may refer to the positive electrode active material layer or the negative electrode active material layer. It is understood that the positive electrode active material layer contains a positive electrode active substance, and the negative electrode active material layer contains a negative electrode active substance. In this application, the term "electrode active material layer" may also be referred to as the "active material layer."

[0134] In the present application, unless otherwise specified, the positive electrode layer at least includes a positive electrode active material layer.

[0135] In the present application, unless otherwise specified, the positive electrode active material layer includes at least positive electrode active particles and generally also includes positive electrode electrolyte particles.

[0136] In this application, unless otherwise specified, “positive electrode active particles” refer to particles containing positive electrode active materials, which have the ability to reversibly release and embed active ions.

[0137] In this application, unless otherwise specified, "positive electrode electrolyte particles" have the same meaning as "positive electrode solid electrolyte" and "positive electrode electrolyte material" and can be used interchangeably to refer to solid electrolytes that can be used in positive electrode films or positive electrode layers. Positive electrode electrolyte particles can enhance the ion conductivity of the positive electrode film or positive electrode layer and reduce interfacial impedance, thereby promoting the charge transfer efficiency between the positive electrode active material and the outside world and fully releasing its capacity.

[0138] In the present application, unless otherwise specified, the negative electrode layer at least includes a negative electrode active material layer.

[0139] In the present application, unless otherwise specified, the negative electrode active material layer at least includes negative electrode active particles, and may or may not include negative electrode electrolyte particles.

[0140] In this application, unless otherwise specified, “negative electrode active particles” refer to particles containing negative electrode active materials, which have the ability to reversibly embed and de-embed active ions.

[0141] In this application, unless otherwise specified, "negative electrode electrolyte particles," "negative electrode solid electrolyte," and "negative electrode electrolyte material" have the same meaning and are used interchangeably to refer to solid electrolytes that can be used in negative electrode films or negative electrode layers. Negative electrode electrolyte particles can enhance the ion conductivity of the negative electrode film or negative electrode layer and reduce interfacial impedance, thereby promoting the charge transfer efficiency between the negative electrode active material and the outside world and fully releasing its capacity.

[0142] In solid-state batteries, the interface contact and interface stability issues are one of the pain points that limit their performance, and poor interface contact will affect the cycle performance of the battery. Due to the "solid-solid contact" characteristics existing in solid-state batteries, the contact between the particles inside the electrode layer includes a large number of point contacts, which cannot completely wet the electrode active material like the electrolyte in the liquid battery, resulting in insufficient interface ion transport within the electrode layer, which in turn leads to unsatisfactory performance of the solid-state battery. By doping solid electrolyte materials into the electrode layer, it is theoretically possible to enhance the ion conductivity of the electrode layer, promote the charge transfer efficiency between the electrode active material and the outside world and the full release of its capacity, and reduce impedance. Among the many solid electrolyte materials, sulfide solid electrolytes have a high ionic conductivity (about 10 -3 ~10 -2 S / cm) and excellent mechanical properties, such as good flexibility, resulting in exceptional ion conductivity and good deformation capacity, making it a solid electrolyte material with the greatest potential for practical application and industrialization. However, sulfide solid electrolytes have poor stability and readily react with moisture in the air, releasing highly toxic hydrogen sulfide gas, which also causes a decrease in ionic conductivity. Furthermore, hydrogen sulfide gas is flammable and explosive, which seriously restricts the practical application of sulfide solid electrolytes.

[0143] Based on this, according to various embodiments and examples of the present application, the embodiments and examples of the present application provide at least one sulfide solid electrolyte and its preparation method, solid electrolyte membrane, electrode plate, solid-state battery, and electrical device, and may also provide a positive electrode membrane, a negative electrode membrane, and a secondary battery. This sulfide solid electrolyte significantly reduces the amount of hydrogen sulfide released by the sulfide electrolyte in an aqueous environment.

[0144] In a first aspect of the present application, a sulfide solid electrolyte is provided, which includes an LGPS-type crystal phase.

[0145] In some embodiments, a sulfide solid electrolyte is provided, which includes an LGPS-type crystal phase; wherein the atomic number ratio of the Sn element to the S element is greater than 1 / 12, and the atomic number ratio of the Sn element to the P element is greater than 1 / 2.

[0146] In some embodiments, the LGPS type crystal phase includes or does not include a cation-substituted element. In some embodiments, when the LGPS type crystal phase includes a cation-substituted element, the cation-substituted element includes Sb.

[0147] In some embodiments, the LGPS type crystalline phase includes or does not include an anion substituting element. In some embodiments, when the LGPS type crystalline phase includes an anion substituting element, the anion substituting element includes at least one of O and Cl.

[0148] In some embodiments, a sulfide solid electrolyte is provided, comprising an LGPS-type crystal phase;

[0149] The LGPS crystal phase includes Li, Sn, P and S elements, wherein the atomic number ratio of Sn and S is greater than 1 / 12, and the atomic number ratio of Sn and P is greater than 1 / 2.

[0150] In some embodiments, the LGPS type crystal phase includes or does not include a cationic substitution element, and also includes or does not include an anionic substitution element;

[0151] When the LGPS type crystal phase includes a cation substitution element, the cation substitution element includes an Sb element;

[0152] When the LGPS type crystal phase includes an anion substitution element, the anion substitution element includes at least one of an O element and a Cl element.

[0153] In this application, unless otherwise specified, "sulfide electrolyte" and "sulfide solid electrolyte" have the same meaning and can be used interchangeably, referring to a solid electrolyte in the form of sulfide, wherein the sulfide electrolyte includes sulfur (S) in the form of sulfide. The "sulfide electrolyte" involved in the embodiments or examples of this application can be in any of the solid electrolyte layer, the positive electrode layer, and the negative electrode layer, and can be contained in the electrolyte material of the solid electrolyte layer, in the positive electrode electrolyte particles, or in the negative electrode electrolyte particles.

[0154] In this application, unless otherwise specified, “LGPS type crystal phase” refers to a tetragonal crystal structure (P42 / nmc ) crystal phase, LGPS type crystal phase corresponds to LGPS type sulfide solid electrolyte; "LGPS type sulfide solid electrolyte" refers to a sulfide solid electrolyte with a tetragonal crystal structure that is the same as or similar to that of lithium germanium phosphorus sulfur (LGPS) sulfide solid electrolyte. 10 GeP2S 12 For example, the tetragonal crystal structure is composed of four basic units: [(M / P)S4] tetrahedron (M = Ge), [PS4] tetrahedron, [LiS6] octahedron, and [LiS4] tetrahedron. [(M / P)S4] tetrahedrons and [LiS6] octahedrons are alternately connected along the c-axis to form long one-dimensional chains. The long chains are connected to each other through the shared vertices of [LiS6] octahedrons and [PS4] tetrahedrons to form a network structure.

[0155] In the sulfide solid electrolyte provided by the present application, in the tetragonal crystal structure of the LGPS type crystal phase, M is partially or completely replaced by Sn, and partial Sb doping is also allowed, and S can be partially replaced by one or both of O and Cl, so that the P content is lower than that of the traditional Li 10 GeP2S 12 P content in the tetragonal phase.

[0156] In this application, unless otherwise specified, "atomic number ratio" refers to the number ratio of specified elements or atoms, which can be measured in moles, in which case it corresponds to "atomic molar ratio".

[0157] In this application, numerical values ​​may be expressed as fractions, for example, "1 / 12" means one twelfth, and "1 / 2" means one half.

[0158] In the present application, unless otherwise specified, it can be determined whether the sulfide solid electrolyte includes an LGPS type crystal phase based on the X-ray diffraction (XRD) pattern. In the present application, unless otherwise specified, the X-ray diffraction pattern of the sulfide solid electrolyte is obtained using a powder sample by using Cu Kα rays. Typically, the 2θ(°) scanning range includes at least 10° to 50° (the scanning range may include 10° to 80°), and the 2θ(°) scanning speed may be 0.02° / second. In some embodiments, the XRD test instrument and parameters are as follows: Bruker-D8 advance, using Cu target Kα1 rays, a wavelength λ of 0.15406nm, the X-ray tube is controlled at 40kV and 40mA, a 2θ(°) scanning range of 10° to 80°, and a 2θ(°) scanning speed of 0.02° / second. Those skilled in the art can determine the XRD pattern based on the data obtained with Li 10 GeP2S 12 Comparative analysis of the XRD standard spectrum confirms whether the sulfide solid electrolyte to be tested includes an LGPS type crystalline phase. In some embodiments, the X-ray diffraction pattern of the sulfide solid electrolyte has peaks at 14.6°, 17.4°, 20.2°, 20.5°, 24.0°, 26.9°, 29.5°, 32.6°, 36.5°, 41.5° and 47.3° near the 2θ (°) diffraction angle of the lower group. Due to differences in measurement factors such as measuring instruments and measurement conditions, the position of a peak or peaks in the actual X-ray diffraction pattern may be slightly offset (for example, ±δ°), but it is understandable that for those skilled in the art, it is possible to identify as a whole whether "an X-ray diffraction pattern including slightly different characteristic peaks actually constitutes an LGPS type crystalline phase". Unless otherwise specified, "±δ°" only represents the error in the diffraction angle position of the peak, and has nothing to do with the peak shape and peak width of the peak. In terms of numerical values, regarding the aforementioned peak position shift ±δ°, δ can be 0.4, 0.3, 0.2, 0.1, etc. according to measurement conditions. For example, in some embodiments, δ=0.2.

[0159] In the present application, unless otherwise specified, the types of elements and the atomic ratios of the elements in the sulfide solid electrolyte can be determined by elemental analysis methods such as inductively coupled plasma spectrometry (ICP method), thereby determining the chemical formula.

[0160] This sulfide solid electrolyte includes an LGPS-type crystal phase. By controlling the atomic ratio of tin (Sn) to sulfur (S) to be greater than 1 / 12 (one-twelfth) and the atomic ratio of Sn to P to be greater than 1 / 2 (one-half), the phosphorus (P) content can be reduced. Based on the hard soft acid base (HASB) theory, compared to the bond strength between hard acid (P) and soft base (S), soft acid (Sn) and soft base (S) can form a stronger chemical bond. This stronger chemical bond is not easily destroyed by water molecules, which can significantly reduce the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in aqueous environments (such as air).

[0161] In sulfide solid electrolytes, the LGPS-type crystal phase may or may not include substituent elements.

[0162] In this application, unless otherwise specified, "substituent element" refers to elements other than Li, Sn, P, and S.

[0163] In some embodiments, the LGPS-type crystalline phase includes acceptable substitutional elements.

[0164] In this application, unless otherwise specified, "acceptable substitution element" means that after the introduction of the substitution element, the LGPS type crystal phase can still be maintained and the hydrogen sulfide release amount in the aqueous environment can still be low (refer to the hydrogen sulfide release level in the following examples).

[0165] In some embodiments, the LGPS crystal phase includes a substituent element. Further, the substituent element may include one or more of a cationic substituent element and an anionic substituent element.

[0166] In the present application, unless otherwise specified, a "cation-substituting element" is an element that can participate in providing cations; in some embodiments, the cation-substituting element can replace part of the P element in the LGPS-type crystal phase.

[0167] In some embodiments, the cation-substituted element includes Sb element. In some embodiments, the cation-substituted element is Sb element.

[0168] In the present application, unless otherwise specified, an “anion substituting element” is an element that can participate in providing anions; in some embodiments, the anion substituting element can replace part of the S element in the LGPS type crystal phase.

[0169] In some embodiments, the anion substituting element includes at least one of O and Cl. In some embodiments, the anion substituting element is at least one of O and Cl.

[0170] In some embodiments, the substituting element includes at least one of Sb, O, and Cl. In some embodiments, the substituting element is at least one of Sb, O, and Cl.

[0171] In sulfide solid electrolytes, the LGPS-type crystal phase may or may not include cationic substitution elements.

[0172] In sulfide solid electrolytes, the LGPS-type crystalline phase may or may not include anionic substitution elements.

[0173] The sulfide solid electrolyte can further reduce the amount of hydrogen sulfide gas released by one or both of cation substitution and anion substitution. On the one hand, cation substitution can be used to increase the content of either Sn element or Sb element in the material structure, which can reduce the P element content. Based on the hard and soft acid-base theory, compared with the bond strength between hard acid (P) and soft base (S), soft acid (Sn or Sb) and soft base (S) have stronger chemical bonds. This stronger chemical bond is not easily destroyed by water molecules, which can reduce the amount of hydrogen sulfide gas released by the sulfide electrolyte in an aqueous environment. On the other hand, anion substitution can be used to replace the S element by any one of the O element and Cl element, which can reduce the S element content in the material structure and reduce the amount of hydrogen sulfide gas released. Cationic substitution and anionic substitution can be combined to better reduce the amount of hydrogen sulfide gas released.

[0174] In this application, the atomic ratio of the cationic substitution element and the P element in the LGPS type crystal phase can be recorded as R Y / P .

[0175] In some embodiments, numerically, R Y / P It can be expressed as the ratio of N5 to N4 (N5 / N4), where N5 is a suitable value greater than or equal to 0, and N4 is a suitable positive number less than 20. In some embodiments, 9≤N4<20, and N4 can also be any of the following values: 9, 10, 11, 12, 12.5, 13, 13.5, 14, 15, 16, 17, 18, 19, 19.5, etc. In some embodiments, 0≤N5≤4, and N5 can also be any of the following values: 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, etc. For R Y / P , N5 and N4 can be combined in any way. In some embodiments, R Y / P Can be selected from the interval consisting of any two N5 / N4 values. Y / PIt can be any of the following values, greater than or equal to any of the following values, greater than or equal to 0 and less than or equal to any of the following values, greater than 0 and less than or equal to any of the following values, or an interval consisting of any two of the following values: 0, 1 / 14, 1.5 / 13.5, 2 / 14, 2.5 / 12.5, 3 / 11, 4 / 11, 4 / 10, 4 / 9, etc.

[0176] In some embodiments, 0≤R Y / P ≤4 / 9, optionally, 0 <R Y / P ≤4 / 9, further optionally, 2 / 14≤R Y / P ≤3 / 11.

[0177] In this application, the atomic ratio of the anion substitution element and the S element in the LGPS type crystal phase can be recorded as R N / S .

[0178] In some embodiments, numerically, R N / S It can be expressed as the ratio of N3 to N2 (N3 / N2), where N3 is a suitable value greater than or equal to 0, and N2 is a suitable positive number less than or equal to 120. In some embodiments, 0≤N3≤34, and N3 can also be any of the following values: 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 5, 6, 7, 8, 9, 10, 12, 12.5, 13, 14, 15, 16, 18, 20, 22, 24, 25, 26, 28, 30, 32, 33, 34, etc. In some embodiments, 86≤N2≤120, and N2 may also be any of the following values: 86, 87, 88, 90, 91, 92, 94, 95, 96, 97, 98, 99, 100, 102, 104, 105, 106, 108, 110, 112, 115, 116, 117, 118, 120, etc. N / S , N3 and N2 can be combined in any way. In some embodiments, R N / S Can be selected from any two intervals consisting of N3 / N2 values. N / S It can be any of the following values, greater than or equal to any of the following values, greater than or equal to 0 and less than or equal to any of the following values, greater than 0 and less than or equal to any of the following values, or an interval consisting of any two of the following values: 0, 3 / 117, 15 / 105, 18 / 102, 24 / 96, 29 / 91, 34 / 91, 34 / 86, etc.

[0179] In some embodiments, N3+N2=120.

[0180] In some embodiments, 0≤R N / S ≤34 / 86, optionally, 0 <RN / S ≤34 / 86, and further optionally, 18 / 102 ≤ R N / S ≤29 / 91.

[0181] By controlling at least one of the atomic number ratios of the cation substitution element to the P element (R Y / P ) and the anion substitution element to the S element (R N / S ) within the foregoing ranges, while reducing the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in an aqueous environment, it is also more conducive to maintaining good ionic conductivity.

[0182] In some embodiments, in the LGPS-type crystal phase, the atomic number ratio of the Sn element to the S element (denoted as R Sn / S ) is greater than 1 / 12 (i.e., greater than 10 / 120), and the atomic number ratio of the Sn element to the P element (denoted as R Sn / P ) is greater than 1 / 2 (i.e., greater than 10 / 20).

[0183] In some embodiments, numerically, R Sn / S can be denoted as the ratio of N1 to N2 (N1 / N2), where N1 is a suitable value greater than 10 and N2 is a suitable positive number less than or equal to 120. In some embodiments, 10 < N1 ≤ 17, and N1 can also be any one of the following values: 11, 12, 13, 14, 15, 16, 17, etc. In some embodiments, 86 ≤ N2 ≤ 120, and N2 can also be any one of the following values: 86, 87, 88, 90, 91, 92, 94, 95, 96, 97, 98, 99, 100, 102, 104, 105, 106, 108, 110, 112, 115, 116, 117, 118, 120, etc. For R Sn / S , the aforementioned N1 and N2 can be combined arbitrarily. In some embodiments, R Sn / S can be selected from the intervals formed by any two N1 / N2 values.

[0184] Non-limitingly, the atomic number ratio of the Sn element to the S element (R Sn / S) can be any of the following values, greater than or equal to any of the following values, greater than 1 / 12 and less than or equal to any of the following values, or an interval consisting of any two of the following values: 11 / 120 (about 0.0917), 14 / 120 (about 0.1167), 15 / 120 (equal to 0.125), 16 / 120 (about 0.1333), 16 / 117 (about 0.1368), 17 / 120 (about 0.14 17), 16 / 105 (about 0.1524), 15 / 96 (about 0.1563), 15 / 91 (about 0.1648), 16 / 96 (about 0.1667), 15 / 86 (about 0.1744), 16 / 91 (about 0.1758), 17 / 96 (about 0.1771), 16 / 86 (about 0.186), 17 / 91 (about 0.1868), 17 / 86 (about 0.1977), etc.

[0185] In some embodiments, R Sn / S >1 / 12, optionally, R Sn / S ≥11 / 120.

[0186] In some embodiments, R Sn / S ≤17 / 86, optionally, 14 / 120≤R Sn / S ≤16 / 91.

[0187] In this application, unless otherwise specified, the atomic ratio of Sn to P in the LGPS crystal phase can be expressed as R Sn / P .

[0188] In some embodiments, numerically, R Sn / P It can be expressed as the ratio of N1 to N4 (N1 / N4), wherein N1 can refer to the above definition, and N4 is a suitable positive number less than 20. In some embodiments, 9≤N4<20, and N4 can also be any of the following values: 9, 10, 11, 12, 12.5, 13, 13.5, 14, 15, 16, 17, 18, 19, 19.5, etc. Sn / P , the aforementioned N1 and N4 can be combined arbitrarily. In some embodiments, R Sn / P It can be selected from any two intervals consisting of N1 / N4 values. Non-limitingly, the atomic number ratio of Sn element and P element (R Sn / P) can be any of the following values, greater than or equal to any of the following values, greater than 1 / 2 and less than or equal to any of the following values, or an interval consisting of any two of the following values: 11 / 19 (about 0.5789), 14 / 16 (equal to 0.875), 15 / 14 (about 1.071), 15 / 13.5 (about 1.111), 16 / 14 (about 1.143), 15 / 12.5 (about 1.2), 15 / 11 (about 1.364), 16 / 11 (about 1.455), 16 / 10 (equal to 1.6), 17 / 9 (about 1.889), etc.

[0189] In some embodiments, R Sn / P >1 / 2, optionally, R Sn / P ≥11 / 19.

[0190] In some embodiments, R Sn / P ≤17 / 9, optionally, 14 / 16≤R Sn / P ≤16 / 10.

[0191] In some embodiments, the LGPS crystal phase satisfies one or more of the following characteristics (any numerical parameter in the following characteristics may also be selected from any appropriate numerical value or range in the context):

[0192] The atomic ratio of Sn and S (R Sn / S ) is greater than 1 / 12, optionally, R Sn / S Greater than or equal to 11 / 120;

[0193] The atomic ratio of Sn and S (R Sn / S ) is less than or equal to 17 / 86, optionally, R Sn / S Greater than or equal to 14 / 120 and less than or equal to 16 / 91;

[0194] The atomic ratio of Sn element to P element (R Sn / P ) is greater than 1 / 2, optionally, R Sn / P Greater than or equal to 11 / 19;

[0195] The atomic ratio of Sn element to P element (R Sn / P ) is less than or equal to 17 / 9, optionally, R Sn / P Greater than or equal to 14 / 16 and less than or equal to 16 / 10.

[0196] By comparing the atomic number ratio of Sn and S (R Sn / S ), the atomic number ratio of Sn element to P element (R Sn / P) is controlled within the aforementioned range, which is more conducive to maintaining good ionic conductivity while reducing the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in an aqueous environment.

[0197] In the sulfide solid electrolyte, the LGPS type crystal phase may or may not include the Sb element. In some embodiments, the LGPS type crystal phase includes the Sb element.

[0198] By doping antimony (Sb) into the LGPS type crystal phase, Sb can replace part of the P element, further reducing the P element content; based on the hard and soft acid-base theory, compared with the bonding strength between hard acid (P) and soft base (S), soft acid (Sb) and soft base (S) also have stronger chemical bonds, which are not easily destroyed by water molecules, and can further reduce the amount of hydrogen sulfide gas released by sulfide solid electrolytes in aqueous environments.

[0199] In this application, the atomic ratio of Sb element to S element in the LGPS type crystal phase can be recorded as R Sb / S .

[0200] In some embodiments, numerically, R Sb / S It can be expressed as the ratio of N5 to N2 (N5 / N2), where N5 is a suitable value greater than or equal to 0, and N2 can refer to the definition above. In some embodiments, 0≤N5≤4, and N5 can also be any of the following values: 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, etc. Sb / S , the aforementioned N5 and N2 can be combined arbitrarily. In some embodiments, R Sb / S The range of any two N5 / N2 values ​​can be selected. Without limitation, the atomic number ratio of Sb element to S element (R Sb / S ) can be any of the following values, greater than or equal to any of the following values, greater than or equal to 0 and less than or equal to any of the following values, greater than 0 and less than or equal to any of the following values, or an interval consisting of any two of the following values: 1 / 120, 1.5 / 120, 2 / 120, 2.5 / 86, 4 / 120, 3 / 117, 3 / 105, 3 / 91, 3 / 86, 4 / 96, 4 / 86, etc. In some embodiments, R Sb / S is 0.

[0201] In this application, the atomic ratio of Sb element to P element in the LGPS type crystal phase can be recorded as R Sb / P .

[0202] In some embodiments, numerically, R Sb / PIt can be denoted as the ratio of N5 to N4 (N5 / N4), where N5 can be referred to the definition in the previous text, and N4 can be referred to the definition in the previous text. N5 and N4 can be combined arbitrarily. In some embodiments, R Sb / P can be selected from the intervals formed by any two N5 / N4 values. Without limitation, the atomic number ratio of Sb element to P element (R Sb / P ) can be any one of the following values, greater than or equal to any one of the following values, greater than or equal to 0 and less than or equal to any one of the following values, greater than 0 and less than or equal to any one of the following values, or selected from the intervals formed by any two of the following values: 1 / 14, 1.5 / 13.5, 2 / 14, 2.5 / 12.5, 3 / 11, 4 / 11, 4 / 10, 4 / 9, etc. In some embodiments, R Sb / P is 0.

[0203] In the present application, in the LGPS-type crystal phase, the atomic number ratio of the sum of Sn element and Sb element to S element can be denoted as R[[ID=??]] (Sn+Sb) / S and numerically equal to the ratio of the sum of the atomic numbers of Sn element and Sb element to the atomic number of S element. Numerically, R (Sn+Sb) / S =R Sn / S +R Sb / S .

[0204] In some embodiments, numerically, R (Sn+Sb) / S can be denoted as the ratio of N6 to N2 (N6 / N2), where N6 is a suitable value greater than 10, and N2 can be referred to the definition in the previous text. In some embodiments, 10 < N6 ≤ 21, and N6 can also be any one of the following values: 11, 12, 13, 14, 15, 16, 16.5, 17, 17.5, 18, 19, 20, 21, etc. For R (Sn+Sb) / S , the aforementioned N6 and N2 can be combined arbitrarily. In some embodiments, R (Sn+Sb) / S can be selected from the intervals formed by any two N6 / N2 values. Without limitation, the atomic number ratio of the sum of Sn element and Sb element to S element (R (Sn+Sb) / S ) can be any one of the following values, greater than or equal to any one of the following values, greater than 10 / 120 and less than or equal to any one of the following values, or selected from the intervals formed by any two of the following values: 11 / 120, 14 / 120, 16 / 120, 16.5 / 120, 17 / 120, 20 / 120, 19 / 117, 21 / 120, 16 / 91, 19 / 105, 21 / 96, 16 / 86, 17.5 / 86, 19 / 86, 20 / 86, 19 / 91, 21 / 86, etc.

[0205] In the present application, in the LGPS-type crystal phase, the atomic number ratio of the sum of Sn element and Sb element to P element can be denoted as R It should be noted that there seems to be an unclear tag "??" in the original text at line 10. If you can provide more specific information about it, the translation can be more accurate.(Sn+Sb) / P . Numerically, R (Sn+Sb) / P =R Sn / P +R Sb / P .

[0206] In some embodiments, numerically, R (Sn+Sb) / P It can be expressed as the ratio of N6 to N4 (N6 / N4), where N6 can refer to the definition above, and N4 can refer to the definition above. (Sn+Sb) / P , N6 and N4 can be combined in any way. In some embodiments, R (Sn+Sb) / P It can be selected from the interval consisting of any two N6 / N4 values. Without limitation, the atomic number ratio of the sum of Sn element and Sb element to P element (R (Sn+Sb) / P ) can be any of the following values, greater than or equal to any of the following values, greater than 10 / 20 and less than or equal to any of the following values, or an interval consisting of any two of the following values: 11 / 19, 14 / 16, 16 / 14, 16.5 / 13.5, 17.5 / 12.5, 19 / 11, 20 / 10 (i.e. 2), 21 / 9, etc.

[0207] In some embodiments, N6+N4=30.

[0208] In some embodiments, 0≤R Sb / S ≤4 / 86, optionally, 0 <R Sb / S ≤4 / 86, further optionally, 2 / 120≤R Sb / S ≤3 / 91.

[0209] In some embodiments, 0≤R Sb / P ≤4 / 9, optionally, 0 <R Sb / P ≤4 / 9, further optionally, 2 / 14≤R Sb / P ≤3 / 11.

[0210] In some embodiments, 10 / 120 <R (Sn+Sb) / S ≤21 / 86 (i.e. 1 / 12 <R (Sn+Sb) / S ≤21 / 86), optionally, 11 / 120≤R (Sn+Sb) / S ≤21 / 86, further optionally, 16 / 120≤R (Sn+Sb) / S ≤19 / 91.

[0211] In some embodiments, 10 / 20 <R (Sn+Sb) / P ≤21 / 9 (i.e. 1 / 2 <R (Sn+Sb) / P ≤21 / 9), optionally, 11 / 19≤R (Sn+Sb) / P ≤21 / 9, further optionally, 16 / 14≤R (Sn+Sb) / P ≤19 / 11.

[0212] In some embodiments, the LGPS crystal phase satisfies one or more of the following characteristics (any numerical parameter in the following characteristics may also be selected from any appropriate numerical value or range in the context):

[0213] The atomic ratio of Sb and S (R Sb / S ) is greater than or equal to 0 and less than or equal to 4 / 86, optionally, R Sb / S greater than 0 and less than or equal to 4 / 86, further optionally, R Sb / S Greater than or equal to 2 / 120 and less than or equal to 3 / 91;

[0214] The atomic ratio of Sb and P (R Sb / P ) is greater than or equal to 0 and less than or equal to 4 / 9, alternatively, greater than or equal to 0 and less than or equal to 4 / 9, further alternatively, greater than or equal to 2 / 14 and less than or equal to 3 / 11;

[0215] The atomic number ratio of the sum of Sn and Sb elements to S element (R (Sn+Sb) / S ) is greater than 1 / 12 and less than or equal to 21 / 86, optionally, R (Sn+Sb) / S Greater than or equal to 11 / 120 and less than or equal to 21 / 86, further optionally, R (Sn+Sb) / S Greater than or equal to 16 / 120 and less than or equal to 19 / 91;

[0216] Alternatively, the atomic number ratio of the sum of Sn element and Sb element to P element (R (Sn+Sb) / P ) is greater than 1 / 2 and less than or equal to 21 / 9, optionally, R (Sn+Sb) / P Greater than or equal to 11 / 19 and less than or equal to 21 / 9, further optionally, R (Sn+Sb) / P Greater than or equal to 16 / 14 and less than or equal to 19 / 11.

[0217] By controlling at least one parameter among the atomic moles of Sb element and S element, the atomic number ratio of the sum of Sn element and Sb element to S element, and the atomic number ratio of the sum of Sn element and Sb element to P element within the aforementioned range, it is beneficial to reduce the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in an aqueous environment while maintaining good ionic conductivity.

[0218] In sulfide solid electrolytes, the LGPS-type crystal phase may or may not include the O element.

[0219] In sulfide solid electrolytes, the LGPS-type crystal phase may or may not include the Cl element.

[0220] In some embodiments, the LGPS type crystal phase includes at least one of an O element and a Cl element.

[0221] In some embodiments, the LGPS-type crystal phase includes O element.

[0222] By doping oxygen (O) elements into the LGPS type crystal phase, the O elements can replace part of the S elements, which is beneficial to further reduce the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in an aqueous environment.

[0223] In this application, the atomic ratio of O element to S element in LGPS type crystal phase can be recorded as R O / S .

[0224] In some embodiments, numerically, R O / S It can be expressed as the ratio of N7 to N2 (N7 / N2), where N7 is a suitable value greater than or equal to 0, and N2 can refer to the definition above. In some embodiments, 0≤N7≤29, and N7 can also be any of the following values: 0, 1, 2, 3, 4, 5, 6, 8, 10, 12, 14, 15, 16, 18, 20, 22, 24, 25, 26, 28, 29, etc. O / S , N7 and N2 can be combined in any way. In some embodiments, R O / S Can be selected from any two intervals consisting of N7 / N2 values. Non-limitingly, the atomic number ratio of O element and S element (R O / S ) can be any of the following values, greater than or equal to any of the following values, greater than or equal to 0 and less than or equal to any of the following values, greater than 0 and less than or equal to any of the following values, or an interval consisting of any two of the following values: 15 / 105, 20 / 96, 20 / 91, 25 / 91, 29 / 86, etc.

[0225] In some embodiments, the LGPS type crystal phase includes O element, optionally, 0 <R O / S ≤29 / 86.

[0226] In some embodiments, 0≤R O / S ≤29 / 86, optionally, 15 / 105≤R O / S ≤20 / 91.

[0227] In some embodiments, the LGPS-type crystal phase includes Cl element.

[0228] By doping chlorine (Cl) element into the LGPS type crystal phase, the Cl) element can replace part of the S element, which is beneficial to further reduce the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in an aqueous environment.

[0229] In this application, the atomic ratio of Cl and S in the LGPS crystal phase can be expressed as R Cl / S .

[0230] In some embodiments, numerically, R Cl / S It can be expressed as the ratio of N8 to N2 (N8 / N2), where N8 is a suitable value greater than or equal to 0, and N2 can refer to the definition above. In some embodiments, 0≤N8≤5, and N8 can also be any of the following values: 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, or 5. Cl / S , N8 and N2 can be combined in any way. In some embodiments, R Cl / S Can be selected from any two intervals consisting of N8 / N2 values. Non-limitingly, the atomic number ratio of Cl element and S element (R Cl / S ) can be any of the following values, greater than or equal to any of the following values, greater than or equal to 0 and less than or equal to any of the following values, greater than 0 and less than or equal to any of the following values, or an interval consisting of any two of the following values: 3 / 117, 4 / 96, 4 / 91, 5 / 86, etc.

[0231] In some embodiments, the LGPS type crystal phase includes Cl elements, optionally, 0 <R Cl / S ≤5 / 86.

[0232] In some embodiments, 0≤R Cl / S ≤5 / 86, optionally, 3 / 117≤R Cl / S ≤4 / 91.

[0233] In some embodiments, the LGPS crystal phase includes at least one of an O element and a Cl element; further, the LGPS crystal may satisfy one or more of the following characteristics (any numerical parameter in the following characteristics may also be selected from any appropriate numerical value or range in the context);

[0234] The LGPS type crystal phase includes O element, optionally, 0 <R O / S ≤29 / 86;

[0235] The atomic ratio of O and S (R O / S ) is greater than or equal to 0 and less than or equal to 29 / 86, optionally, R O / S Greater than or equal to 15 / 105 and less than or equal to 20 / 91;

[0236] The LGPS type crystal phase includes Cl element, further optionally, 0 <R Cl / S ≤5 / 86;

[0237] The atomic ratio of Cl and S (R Cl / S) is greater than or equal to 0 and less than or equal to 5 / 86, optionally, R Cl / S Greater than or equal to 3 / 117 and less than or equal to 4 / 91.

[0238] By controlling at least one parameter of the atomic number ratio of the O element to the S element and the atomic number ratio of the Cl element to the S element within the aforementioned range, it is beneficial to reduce the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in an aqueous environment while maintaining good ionic conductivity.

[0239] In some embodiments, the LGPS type crystal phase includes or excludes the Sb element, and includes or excludes the O element, and includes or excludes the Cl element; wherein the atomic number ratio of the Li element, Sn element, P element, Sb element, S element, O element and Cl element is (10+xm):(1+x):(2-xy):y:(12-zm):z:m; wherein, 0 <x≤0.7,0≤y≤0.4,0≤z≤2.9,0≤m≤0.5;

[0240] At this time, R Sn / S＝ (1+x) / (12-zm), R Sn / P =(1+x) / (2-xy), R Sb / S =y / (12-zm), R (Sn+Sb) / S =(1+x+y) / (12-zm), R (Sn+Sb) / P =(1+x+y) / (2-xy), R O / S =z / (12-zm), R Cl / S =m / (12-zm).

[0241] In some embodiments, the chemical formula of the LGPS type crystal phase is Li 10+x-m Sn 1+x P 2-x-y Sb y S 12-z-m O z Cl m .

[0242] Non - restrictively, 0 ≤ (z + m) ≤ 3.4. In some embodiments, (z + m) > 0. At this time, the LGPS - type crystal phase includes at least one of O element and Cl element. Non - restrictively, z + m can be any of the following values, greater than 0 and less than or equal to any of the following values, greater than or equal to 0 and less than or equal to any of the following values, or selected from the intervals formed by any two of the following values: 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.6, 0.8, 1, 1.0, 1.1, 1.2, 1.25, 1.3, 1.4, 1.6, 1.8, 2, 2.2, 2.4, 2.5, 2.6, 2.8, 2.9, 3.0, 3.1, 3.2, 3.3, 3.4, etc. z + m can also be selected from any suitable range of the following: 0 < (z + m) ≤ 3.4, 1.8 ≤ (z + m) ≤ 3.4, etc.

[0243] Non - restrictively, 0 < x ≤ 0.7. x can also be any of the following values, greater than 0 and less than or equal to any of the following values, or selected from the intervals formed by any two of the following values: 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, etc. As a non - restrictive example, x can be selected from any suitable range of the following: 0 < x ≤ 0.6, 0 < x ≤ 0.5, 0.1 ≤ x ≤ 0.7, 0.1 ≤ x ≤ 0.6, 0.4 ≤ x ≤ 0.6, 0.45 ≤ x ≤ 0.55, 0.1 ≤ x ≤ 0.5, 0.4 ≤ x ≤ 0.7, 0.5 ≤ x ≤ 0.7, etc.

[0244] Non - restrictively, 0 ≤ y ≤ 0.4. y can also be any of the following values, greater than or equal to 0 and less than or equal to any of the following values, greater than 0 and less than or equal to any of the following values, or selected from the intervals formed by any two of the following values: 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, etc. As a non - restrictive example, y can be selected from any suitable range of the following: 0 ≤ y ≤ 0.3, 0 ≤ y ≤ 0.2, 0.2 ≤ y ≤ 0.4, 0.15 ≤ y ≤ 0.25, 0.2 ≤ y ≤ 0.3, 0.1 ≤ y ≤ 0.3, etc.

[0245] Without limitation, 0≤z≤2.9. z can also be any of the following values, greater than or equal to 0 and less than or equal to any of the following values, greater than 0 and less than or equal to any of the following values, or an interval consisting of any two of the following values: 0.1, 0.15, 0.2, 0.25, 0.3, 0.4, 0.5, 0.6, 0.8, 1, 1.0, 1.1, 1.2, 1.25, 1.3, 1.4, 1.6, 1.8, 2, 2.2, 2.4, 2.5, 2.6, 2.8, 2.9, etc. As a non-limiting example, z can be selected from any of the following suitable ranges: 0≤z≤2.5, 0≤z≤2, 0≤z≤1.5, 1.5≤z≤2.9, 1.5≤z≤2.5, 1.5≤z≤2, 1≤z≤2, 1≤z≤2.5, etc.

[0246] Without limitation, 0≤m≤0.5. m may also be any of the following values, greater than or equal to 0 and less than or equal to any of the following values, greater than 0 and less than or equal to any of the following values, or selected from an interval consisting of any two of the following values: 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, etc. As non-limiting examples, m may be selected from any of the following suitable ranges: 0≤m≤0.4, 0≤m≤0.3, 0.3≤m≤0.5, 0.3≤m≤0.4, 0.2≤m≤0.4, 0.25≤m≤0.35, etc.

[0247] In some embodiments, the LGPS crystal phase satisfies one or more of the following characteristics (any numerical parameter in the following characteristics may also be selected from any appropriate numerical value or range in the context):

[0248] (z+m)>0, optionally, 0<(z+m)≤3.4, further optionally, 1.8≤(z+m)≤3.4;

[0249] 0.1≤x≤0.7, optionally, 0.4≤x≤0.6;

[0250] 0.2≤y≤0.4, optionally, 0.2≤y≤0.3;

[0251] 1.5≤z≤2.9, optionally, 1.5≤z≤2.5;

[0252] 0.3≤m≤0.5, optionally, 0.3≤m≤0.4.

[0253] By controlling the content of Sn element and the doping amounts of Sb element, O element and Cl element in the LGPS type crystal phase within the aforementioned range, the Sn element can be used to reduce the P element content, the Sb element can be selectively used (or not used) to reduce the P element content, the O element can be selectively used to replace the S element, and the Cl element can be selectively used to replace the S element.

[0254] When cation substitution and anion substitution are performed simultaneously, (z+m)>0, which can more effectively reduce the amount of hydrogen sulfide gas released.

[0255] In addition, by controlling one or more parameters among x, y, z and m within the aforementioned range, it is advantageous to reduce the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in an aqueous environment while maintaining good ionic conductivity.

[0256] In some embodiments, the LGPS-type crystalline phase satisfies one, any two, or three of the following characteristics:

[0257] y=0;

[0258] z = 0;

[0259] m=0.

[0260] In some embodiments, y=0, optionally, y=z=0, and further optionally y=m=0.

[0261] In some embodiments, z=0, optionally, z=m=0.

[0262] In some embodiments, m=0.

[0263] When y=0, the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in an aqueous environment can be reduced without introducing the Sb element.

[0264] When z=0, the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in an aqueous environment can be reduced without O element doping.

[0265] When m=0, the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in an aqueous environment can be reduced without Cl element doping.

[0266] In some embodiments, y=0, z=0, and m=0.

[0267] When y=0, z=0, and m=0, the amount of hydrogen sulfide gas released from the sulfide solid electrolyte in an aqueous environment can be reduced by controlling the atomic number ratio of the Sn element.

[0268] In some embodiments, 0 <y≤0.4,z=0,m=0。

[0269] When 0 < y ≤ 0.4, z = 0, and m = 0, based on the aforementioned cation substitution method, it is possible to reduce the hydrogen sulfide gas release amount of the sulfide solid electrolyte in an aqueous environment while maintaining good ionic conductivity.

[0270] In some embodiments, y = 0, 0 < z ≤ 2.9, and m = 0.

[0271] When y = 0, 0 < z ≤ 2.9, and m = 0, based on O element doping, it is possible to reduce the hydrogen sulfide gas release amount of the sulfide solid electrolyte in an aqueous environment while maintaining good ionic conductivity.

[0272] In some embodiments, y = 0, z = 0, and 0 < m ≤ 0.5.

[0273] When y = 0, z = 0, and 0 < m ≤ 0.5, based on Cl element doping, it is possible to reduce the hydrogen sulfide gas release amount of the sulfide solid electrolyte in an aqueous environment while maintaining good ionic conductivity.

[0274] In some embodiments, the LGPS-type crystal phase includes one or more of the compounds represented by the following chemical formulas: Li 10.5 Sn 1.5 P 1.5 S 12 、Li 10.5 Sn 1.5 P 1.3 Sb 0.2 S 12 、Li 10.5 Sn 1.5 P 1.5 S 10.5 O 1.5 、Li<0000​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​

[0275] By providing one or more of the aforementioned LGPS-type sulfide electrolytes in the sulfide solid electrolyte, it is more advantageous to achieve both reduced hydrogen sulfide gas release and better ionic conductivity.

[0276] In some embodiments, the 2θ (°) diffraction angle in the X-ray diffraction pattern of the sulfide solid electrolyte has a characteristic peak consistent with the LGPS type crystal phase. The definition and identification method of "LGPS type crystal phase" can be found in the above text.

[0277] In some embodiments, the 2θ (°) diffraction angle in the X-ray diffraction pattern of the sulfide solid electrolyte has peaks at 14.6±δ°, 17.4±δ°, 20.2±δ°, 20.5±δ°, 24.0±δ°, 26.9±δ°, 29.5±δ°, 32.6±δ°, 36.5±δ°, 41.5±δ° and 47.3±δ°, where δ can be found above; optionally, δ is 0.2 or 0.1.

[0278] In some embodiments, the X-ray diffraction pattern of the sulfide solid electrolyte is obtained by using Cu Kα radiation, and in some embodiments, the X-ray diffraction pattern of the sulfide solid electrolyte is obtained by using Cu Kα1 radiation.

[0279] In some embodiments, the X-ray diffraction pattern of the sulfide solid electrolyte is obtained by powder X-ray diffraction testing.

[0280] In some embodiments, the X-ray diffraction pattern of the sulfide solid electrolyte satisfies at least one of the following characteristics:

[0281] The 2θ (°) diffraction angle in the X-ray diffraction pattern of the sulfide solid electrolyte has peaks at 14.6 ± δ°, 17.4 ± δ°, 20.2 ± δ°, 20.5 ± δ°, 24.0 ± δ°, 26.9 ± δ°, 29.5 ± δ°, 32.6 ± δ°, 36.5 ± δ°, 41.5 ± δ°, and 47.3 ± δ°, where δ can be found above; optionally, δ is 0.2 or 0.1 (in some embodiments, δ is 0.2; in other embodiments, δ is 0.1);

[0282] The X-ray diffraction pattern of the sulfide solid electrolyte was obtained by using Cu Kα radiation;

[0283] The X-ray diffraction pattern of the sulfide solid electrolyte was obtained by powder X-ray diffraction test.

[0284] The chemical composition of the sulfide solid electrolyte can be confirmed by X-ray diffraction (XRD) detection.

[0285] In a second aspect of the present application, a method for preparing a sulfide solid electrolyte is provided, which can be used to prepare the sulfide solid electrolyte described in the first aspect of the present application.

[0286] In some embodiments, the method for preparing a sulfide solid electrolyte comprises the following steps:

[0287] S100: providing a precursor mixture including Li2S, P2S5, SnS2 and elemental sulfur according to a required raw material stoichiometric ratio, wherein the precursor mixture includes or does not include a cation source, and the precursor mixture includes or does not include an anion source; wherein the cation source is a raw material for providing a cationic substitution element, and the anion source is a raw material for providing an anionic substitution element;

[0288] Optionally, when the sulfide solid electrolyte includes a cation-substituting element, the cation-substituting element includes an Sb element;

[0289] Optionally, when the sulfide solid electrolyte includes an anion substituting element, the anion substituting element includes at least one of an O element and a Cl element;

[0290] Further optionally, when the sulfide solid electrolyte contains Sb element, the precursor mixture includes Sb2S3; when the sulfide solid electrolyte contains O element, the precursor mixture includes P2O5; when the sulfide solid electrolyte contains Cl element, the precursor mixture includes LiCl;

[0291] S200: sintering the precursor mixture in an inert atmosphere to prepare a sulfide solid electrolyte including an LGPS type crystal phase; in the LGPS type crystal phase, the atomic ratio of Sn element to S element is greater than 1 / 12, and the atomic ratio of Sn element to P element is greater than 1 / 2;

[0292] Optionally, in the step of sintering the precursor mixture in an inert atmosphere, the sintering temperature (which may be denoted as T1) may be 520°C to 620°C.

[0293] In this application, unless otherwise specified, "providing raw materials in the desired stoichiometric ratio" in step S100 refers to providing the raw materials in the desired stoichiometric ratio to achieve the target chemical formula. Once the target chemical formula is determined, those skilled in the art will be able to select appropriate precursor raw materials and the appropriate stoichiometric ratio. During the sintering process in step S200, sulfur typically evaporates and is lost. Therefore, in step S100, elemental sulfur is typically added in excess.

[0294] Without limitation, the weight percentage of elemental sulfur relative to the precursor mixture may be 2.9 wt % to 3.1 wt %, for example, 2.9 wt %, 3 wt %, 3.1 wt %, etc.

[0295] Without limitation, in step S200, the sintering temperature T1 can be 520℃~620℃, optionally 530℃~620℃, or any two of the following temperatures or a range consisting of any two of the following temperatures: 520℃, 530℃, 540℃, 550℃, 560℃, 570℃, 580℃, 590℃, 600℃, 610℃, 620℃, etc.

[0296] Without limitation, in step S200 , the inert atmosphere may be an argon atmosphere.

[0297] In some embodiments, the method for preparing a sulfide solid electrolyte satisfies one or more of the following characteristics (any numerical parameter in the following characteristics can also be selected from any appropriate value or range in the context):

[0298] The weight percentage of elemental sulfur relative to the precursor mixture is 2.9 wt% to 3.1 wt%;

[0299] The inert atmosphere is argon atmosphere;

[0300] The sintering temperature T1 is 520℃~620℃, and can be selected as 530℃~620℃;

[0301] The prepared sulfide solid electrolyte is the sulfide solid electrolyte described in the first aspect of the present application.

[0302] The sulfide solid electrolyte described in the first aspect of the present application can be obtained by sintering a corresponding precursor mixture at a certain sintering temperature in the presence of excess sulfur.

[0303] In a third aspect of the present application, a solid electrolyte membrane is provided, comprising at least one of the sulfide solid electrolyte described in the first aspect of the present application and the sulfide solid electrolyte prepared by the preparation method described in the second aspect of the present application.

[0304] Without limitation, the solid electrolyte membrane may be an independent solid electrolyte membrane sheet, which is then used to assemble a solid-state battery; the solid electrolyte membrane may also be a solid electrolyte membrane layer present in a composite structure.

[0305] The solid electrolyte membrane can be prepared using conventional methods in the field of solid-state batteries, such as pressing the solid electrolyte material into a membrane.

[0306] In some embodiments, the solid electrolyte membrane is an all-solid-state electrolyte membrane.

[0307] In this application, unless otherwise specified, "all-solid-state electrolyte membrane" refers to a solid electrolyte membrane whose constituent materials are all solid.

[0308] In another aspect of the present application, a solid electrolyte membrane is provided, which includes at least one of the sulfide solid electrolyte described in the first aspect of the present application and the sulfide solid electrolyte prepared by the preparation method described in the second aspect of the present application.

[0309] In another aspect of the present application, a positive electrode film is provided, which includes a positive electrode active material layer, and the positive electrode active material layer includes at least one of the sulfide solid electrolyte described in the first aspect of the present application and the sulfide solid electrolyte prepared by the preparation method described in the second aspect of the present application.

[0310] Without limitation, the positive electrode film can be a standalone positive electrode film sheet or a positive electrode sheet, which can be used to assemble a solid-state battery. The positive electrode film can also be a positive electrode film layer present in a multi-layer composite structure. For example, the constituent materials of the positive electrode film layer can be pressed into a film on the surface of a solid electrolyte layer. As a non-limiting example, the positive electrode film can be a positive electrode layer or a portion of a positive electrode layer of a solid-state battery.

[0311] In some embodiments, the negative electrode film is an all-solid-state positive electrode film.

[0312] In this application, unless otherwise specified, "all-solid-state cathode film" refers to a cathode film whose constituent materials are all solid.

[0313] In another aspect of the present application, a positive electrode membrane is provided, which includes a positive electrode current collector and a positive electrode active material layer located on at least one side of the positive electrode current collector, and the positive electrode active material layer includes at least one of the sulfide solid electrolyte described in the first aspect of the present application and the sulfide solid electrolyte prepared by the preparation method described in the second aspect of the present application.

[0314] In another aspect of the present application, a negative electrode membrane is provided, which includes a negative electrode active material layer, and the negative electrode active material layer includes at least one of the sulfide solid electrolyte described in the first aspect of the present application and the sulfide solid electrolyte prepared by the preparation method described in the second aspect of the present application.

[0315] Without limitation, the negative electrode film can be a standalone negative electrode film sheet or negative electrode sheet, which can be used to assemble a solid-state battery. The negative electrode film can also be a negative electrode film layer present in a multi-layer composite structure. For example, the constituent materials of the negative electrode film layer can be pressed into a film on the surface of a solid electrolyte layer. As a non-limiting example, the negative electrode film can be a negative electrode layer or a portion of a negative electrode layer of a solid-state battery.

[0316] In some embodiments, the negative electrode film is an all-solid-state negative electrode film.

[0317] In this application, unless otherwise specified, "all-solid-state anode film" refers to an anode film whose constituent materials are all solid.

[0318] In another aspect of the present application, a negative electrode membrane is provided, which includes a negative electrode current collector and a negative electrode active material layer located on at least one side of the negative electrode current collector, and the negative electrode active material layer includes at least one of the sulfide solid electrolyte described in the first aspect of the present application and the sulfide solid electrolyte prepared by the preparation method described in the second aspect of the present application.

[0319] For the solid electrolyte membrane, positive electrode membrane or negative electrode membrane provided with the aforementioned sulfide solid electrolyte, the sulfide solid electrolyte has high stability in an aqueous environment (such as air), low hydrogen sulfide release, and good chemical stability of the material, so that the sulfide solid electrolyte in the solid electrolyte membrane, positive electrode membrane or negative electrode membrane has good quality stability, which is beneficial for the corresponding secondary battery or solid-state battery to give full play to the high ionic conductivity advantage of the sulfide solid electrolyte and have good cycle performance.

[0320] In the fourth aspect of the present application, an electrode plate is provided, which includes an electrode active material layer, the electrode active material layer includes an electrode active substance, and the electrode active material layer also includes at least one of the sulfide solid electrolyte described in the first aspect of the present application and the sulfide solid electrolyte prepared by the preparation method described in the second aspect of the present application.

[0321] In some embodiments, the electrode plate is a positive electrode plate, the electrode active material layer is referred to as a positive electrode active material layer, and the electrode active substance is referred to as a positive electrode active substance;

[0322] Alternatively, the electrode plate is a negative electrode plate, the electrode active material layer is recorded as a negative electrode active material layer, and the electrode active substance is recorded as a negative electrode active substance.

[0323] In this application, unless otherwise specified, the electrode plate includes an electrode active material layer. As previously described, the electrode active material layer includes an electrode active substance. In the electrode plate, the electrode active substance may itself constitute particulate matter or may be contained in electrode active particles. Unless otherwise specified, the electrode active material layer in the electrode plate provided in this aspect also includes a sulfide solid electrolyte. Furthermore, the electrode active material layer includes at least one of the sulfide solid electrolyte described in the first aspect of this application and the sulfide solid electrolyte prepared by the preparation method described in the second aspect of this application.

[0324] In some embodiments, the electrode active material layer includes electrode active particles, and the electrode active material layer also includes at least one of the sulfide solid electrolyte described in the first aspect of this application and the sulfide solid electrolyte prepared by the preparation method described in the second aspect of this application. The electrode plate can be a positive electrode plate, and the electrode active particles are positive electrode active particles. In this case, a positive electrode plate is provided, which includes a positive electrode active material layer, and the positive electrode active material layer includes positive electrode active particles and the aforementioned sulfide solid electrolyte. The electrode plate can also be a negative electrode plate, and the electrode active particles are negative electrode active particles. In this case, a negative electrode plate is provided, which includes a negative electrode active material layer, and the negative electrode active material layer includes negative electrode active particles and the aforementioned sulfide solid electrolyte.

[0325] For the electrode plates provided with the aforementioned sulfide solid electrolyte, the sulfide solid electrolyte has high stability in an aqueous environment (such as air), low hydrogen sulfide release, and good chemical stability of the material, so that the electrode plates have good quality stability. The secondary battery or solid-state battery assembled using the electrode plates can give full play to the high ionic conductivity advantage of the sulfide solid electrolyte and have good cycle performance.

[0326] The electrode plate can be a positive electrode plate or a negative electrode plate.

[0327] In another aspect of the present application, a secondary battery is provided, which includes the sulfide solid electrolyte described in the first aspect of the present application, the sulfide solid electrolyte prepared by the preparation method described in the second aspect of the present application, the solid electrolyte membrane described in the third aspect of the present application, the aforementioned positive electrode membrane, the aforementioned negative electrode membrane and at least one of the electrode plates described in the fourth aspect of the present application.

[0328] In the present application, unless otherwise specified, the "secondary battery" provided above in the present application includes a positive electrode sheet, a negative electrode sheet, and a solid electrolyte layer located between the positive electrode sheet and the negative electrode sheet.

[0329] In this application, unless otherwise specified, a "positive electrode sheet" includes a positive electrode active material layer. In some embodiments, the positive electrode sheet in the secondary battery is the aforementioned positive electrode film.

[0330] In this application, unless otherwise specified, the "negative electrode sheet" includes the negative electrode active material layer. In some embodiments, the negative electrode sheet in the secondary battery is the aforementioned negative electrode film.

[0331] In this application, unless otherwise specified, the "solid electrolyte layer" includes a solid electrolyte. In some embodiments, the solid electrolyte layer is a solid electrolyte membrane layer composed of the solid electrolyte membrane described in the third aspect of this application.

[0332] When a secondary battery is charged, active ions are released from the positive electrode and embedded in the negative electrode through the solid electrolyte layer. When the secondary battery is discharged, active ions are released from the negative electrode and embedded in the positive electrode. The active ions are not specifically limited and can be lithium ions, in which case it corresponds to a lithium-ion secondary battery.

[0333] In the fifth aspect of the present application, a solid-state battery is provided, which includes the sulfide solid electrolyte described in the first aspect of the present application, the sulfide solid electrolyte prepared by the preparation method described in the second aspect of the present application, the solid electrolyte membrane described in the third aspect of the present application, the aforementioned positive electrode membrane, the aforementioned negative electrode membrane and at least one of the electrode plates described in the fourth aspect of the present application.

[0334] In some embodiments, the solid-state battery includes at least one of the sulfide solid electrolyte described in the first aspect of this application, the sulfide solid electrolyte prepared by the preparation method described in the second aspect of this application, the solid electrolyte membrane described in the third aspect of this application, and the electrode plate described in the fourth aspect of this application.

[0335] In some embodiments, the positive electrode layer in the solid-state battery includes the aforementioned positive electrode film, and may further be the aforementioned positive electrode film.

[0336] In some embodiments, the negative electrode layer in the solid-state battery includes the aforementioned negative electrode film, and may further be the aforementioned negative electrode film.

[0337] In some embodiments, the solid electrolyte layer in the solid-state battery includes the solid electrolyte membrane described in the third aspect of the present application, and may further be the solid electrolyte membrane described in the third aspect of the present application.

[0338] In some embodiments, the solid-state battery is a sulfide all-solid-state battery.

[0339] The "solid-state battery" provided in the fifth aspect of the present application includes at least one of the sulfide solid electrolyte described in the first aspect of the present application and the sulfide solid electrolyte prepared by the preparation method described in the second aspect of the present application. Therefore, it is a sulfide solid-state battery.

[0340] In this application, unless otherwise specified, a "sulfide solid-state battery" refers to a solid-state battery in which the electrolyte involved in the battery includes a sulfide solid electrolyte. The sulfide solid electrolyte can be located in at least one of the positive electrode layer, negative electrode layer, and solid electrolyte layer of the sulfide solid-state battery. The sulfide solid-state battery can further be an all-solid-state battery.

[0341] In this application, unless otherwise specified, "all-solid-state battery" refers to a solid-state battery in which the electrolytes in the battery are all solid electrolytes. In this case, the positive electrode layer, the negative electrode layer and the electrolyte part are all made of solid materials, and no liquid electrolyte is provided in the battery, so it can be called an "all-solid-state battery".

[0342] In this application, unless otherwise specified, a "solid-state battery" in any embodiment or example may be, but is not limited to, a sulfide all-solid-state battery. Unless otherwise specified, a "sulfide all-solid-state battery" refers to an all-solid-state battery in which the electrolyte involved in the battery includes a sulfide solid electrolyte. The sulfide solid electrolyte may be located in at least one of the positive electrode layer, negative electrode layer, and solid electrolyte layer of the sulfide all-solid-state battery.

[0343] The types of solid electrolytes present in different membrane layers of a secondary battery or solid-state battery can be the same or different. For example, the positive electrode electrolyte particles, the negative electrode electrolyte particles, and the solid electrolyte in the solid electrolyte layer can be the same or different.

[0344] In the secondary battery or solid-state battery provided by the present application, at least one of the positive electrode electrolyte particles, the negative electrode electrolyte particles, and the solid electrolyte in the solid electrolyte layer comprises the sulfide solid electrolyte described in the first aspect of the present application.

[0345] In a secondary battery or solid-state battery provided with the aforementioned sulfide solid electrolyte, the sulfide solid electrolyte may be provided in one or more of the positive electrode layer, the negative electrode layer, and the solid electrolyte layer.

[0346] As a non-limiting example, the positive electrode electrolyte particles, the negative electrode electrolyte particles and the solid electrolyte in the solid electrolyte layer can each independently include solid electrolyte materials that are well known in the art and can be used for solid-state batteries. For example, they can each independently include one or more of the following materials: one or more of sulfide solid electrolytes, halide solid electrolytes, oxide solid electrolytes, polymer solid electrolytes, etc.

[0347] In the sixth aspect of the present application, an electrical device is provided, which includes the sulfide solid electrolyte described in the first aspect of the present application, the sulfide solid electrolyte prepared by the preparation method described in the second aspect of the present application, the solid electrolyte membrane described in the third aspect of the present application, the aforementioned positive electrode membrane, the aforementioned negative electrode membrane, the electrode plate described in the fourth aspect of the present application, the aforementioned secondary battery and at least one of the solid-state battery described in the fifth aspect of the present application.

[0348] In some embodiments, the electrical device includes at least one of the sulfide solid electrolyte described in the first aspect of this application, the sulfide solid electrolyte prepared by the preparation method described in the second aspect of this application, the solid electrolyte membrane described in the third aspect of this application, the electrode plate described in the fourth aspect of this application, and the solid-state battery described in the fifth aspect of this application.

[0349] The following is some description about the solid electrolyte layer.

[0350] The solid electrolyte layer plays the role of conducting ions between the positive electrode layer and the negative electrode layer, and can also isolate the positive electrode layer and the negative electrode layer to prevent the positive and negative electrodes from short-circuiting.

[0351] It is understood that the solid electrolyte layer includes a solid electrolyte. The solid electrolyte in the solid electrolyte layer can be a solid electrolyte material known in the art that can be used for solid-state batteries.

[0352] In some embodiments, the solid electrolyte layer comprises the sulfide solid electrolyte described in the first aspect of the present application.

[0353] In some embodiments, the solid electrolyte layer may be pressed from a solid electrolyte material into a solid electrolyte membrane, which may be a solid electrolyte membrane sheet or a solid electrolyte membrane layer.

[0354] In some embodiments, the thickness of the solid electrolyte layer may be 0.1 μm to 1000 μm, and may be optionally 10 μm to 100 μm, 100 μm to 800 μm, 500 μm to 800 μm, or the like.

[0355] The following is some description about the positive electrode film and the positive electrode layer.

[0356] In this application, unless otherwise specified, "positive electrode film" refers to a film that can be used as a positive electrode of a solid-state battery, including at least a positive electrode active material layer and usually also a positive electrode current collector.

[0357] The positive electrode layer can be provided by a positive electrode sheet or positive electrode membrane that can be used in solid-state batteries in the art. Alternatively, the constituent materials of the positive electrode layer can be directly pressed onto one surface of the solid electrolyte layer to form a positive electrode membrane layer. The positive electrode membrane can be combined with other films suitable for the positive electrode to form a positive electrode sheet or positive electrode layer.

[0358] The positive electrode layer can be prepared by a dry process or a wet process. For example, a dry process can be used to press a positive electrode film, which can be a positive electrode film sheet or a positive electrode film layer. For another example, a wet process can be used to coat a positive electrode film, which can be a positive electrode film layer.

[0359] In some embodiments, the positive electrode film includes a positive electrode current collector and a positive electrode active material layer disposed on at least one surface of the positive electrode current collector. The definition of the positive electrode active material layer can be found in the above text.

[0360] In some embodiments, the positive electrode current collector may be a metal foil or a composite current collector. For example, aluminum foil may be used as the metal foil. In the positive electrode current collector, the composite current collector may include a polymer material base layer and a metal layer formed on at least one surface of the polymer material base layer. In the positive electrode current collector, the composite current collector may be obtained by forming a metal material on a polymer material substrate. In the positive electrode current collector, non-limiting examples of the metal material may include one or more of aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy. In the positive electrode current collector, non-limiting examples of the polymer material substrate may include one or more of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), polyethylene (PE), etc.

[0361] Without limitation, in the positive electrode film or positive electrode layer, the thickness of the positive electrode active material layer is 30μm to 400μm, optionally 60μm to 130μm, and can also be any of the following thicknesses or an interval consisting of any two of the following thicknesses: 30μm, 40μm, 50μm, 60μm, 80μm, 100μm, 120μm, 130μm, 140μm, 150μm, 160μm, 180μm, 200μm, etc.

[0362] In this application, unless otherwise specified, the "thickness of the positive electrode active material layer" refers to the total thickness of the positive electrode film or positive electrode layer. When the positive electrode active material layer is provided on both sides of the positive electrode current collector, the thickness of the positive electrode active material layer refers to the sum of the thicknesses on both sides.

[0363] As a non-limiting example, the positive electrode current collector has two surfaces facing away from each other in its thickness direction, and the positive electrode active material layer is disposed on either or both of the two facing surfaces of the positive electrode current collector.

[0364] The positive electrode film and the positive electrode layer each include a positive electrode active material layer. The positive electrode active material layer includes positive electrode active particles containing a positive electrode active material.

[0365] Without limitation, the weight percentage of the positive electrode active particles or the positive electrode active substance in the positive electrode active material layer can be ≥70wt%, further ≥80wt%, further ≥90wt%, and can also be any of the following weight percentages or an interval consisting of any two of the following weight percentages: 70wt%, 75wt%, 80wt%, 82wt%, 84wt%, 85wt%, 86wt%, 88wt%, 90wt%, 92wt%, 94wt%, 95wt%, 96wt%, 97wt%, 98wt%, 99wt%, etc.

[0366] In some embodiments, the positive electrode active material layer includes positive electrode electrolyte particles. Without limitation, the weight proportion of the positive electrode electrolyte particles in the positive electrode active material layer can be 0.1wt% to 30wt%, optionally 5wt% to 20wt%, and the weight proportion of the positive electrode electrolyte particles in the positive electrode active material layer can also be any of the following weight percentages or a range selected from any two of the following weight percentages: 0.1wt%, 0.2wt%, 0.4wt%, 0.5wt%, 0.6wt%, 0.8wt%, 1wt%, 1 .2wt%, 1.5wt%, 1.6wt%, 1.8wt%, 2wt%, 2.5wt%, 3wt%, 3.5wt%, 4wt%, 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, 10wt%, 12wt%, 14wt%, 15wt%, 16wt%, 18wt%, 20wt%, 22wt%, 24wt%, 25wt%, 26wt%, 28wt%, 30wt%, etc.

[0367] In some embodiments, the positive electrode active material layer includes positive electrode active particles and positive electrode electrolyte particles.

[0368] In some embodiments, the positive electrode active material in the positive electrode active particles can be a battery-use positive electrode active material known in the art. As non-limiting examples, the positive electrode active material can include one or more of the following materials: olivine-structured lithium-containing phosphates, lithium transition metal oxides, and their respective modified compounds. However, this application is not limited to these materials; other conventional materials that can be used as battery positive electrode active materials may also be used. These positive electrode active materials can be used alone or in combination of two or more. Examples of lithium transition metal oxides include, but are not limited to, one or more of lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide, and their modified compounds. Non-limiting examples of olivine-structured lithium-containing phosphates include, but are not limited to, one or more of lithium iron phosphate, a composite material of lithium iron phosphate and carbon, lithium manganese phosphate, a composite material of lithium manganese phosphate and carbon, lithium iron manganese phosphate, and a composite material of lithium iron manganese phosphate and carbon. Non-limiting examples of lithium cobalt oxides may include LiCoO2; non-limiting examples of lithium nickel oxides may include LiNiO2; non-limiting examples of lithium manganese oxides may include LiMnO2, LiMn2O4, etc.; non-limiting examples of lithium nickel cobalt manganese oxides may include LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (also referred to as NCM 333 ), LiNi 0.5 Co 0.2 Mn0.3 O2 (also referred to as NCM 523 ), LiNi 0.5 Co 0.25 Mn 0.25 O2 (also referred to as NCM 211 ), LiNi 0.6 Co 0.2 Mn 0.2 O2 (also referred to as NCM 622 ), LiNi 0.8 Co 0.1 Mn 0.1 O2 (also referred to as NCM 811 ) etc. Non-limiting examples of lithium nickel cobalt aluminum oxide may include LiNi 0.80 Co 0.15 Al 0.05 O2. An example of lithium iron phosphate is LiFePO4 (also referred to as LFP). An example of lithium manganese phosphate is LiMnPO4.

[0369] Taking a solid-state battery in which active ions include lithium ions as an example, it is understandable that the solid-state battery will be accompanied by the deintercalation and consumption of lithium (Li) during the charge and discharge process, and the content of Li in the positive electrode layer is different when the battery is discharged to different states. In the exemplary description of the positive electrode active material in this application, unless otherwise specified, the content of Li can be the initial state of the material or the non-initial state after the charge and discharge cycle. The positive electrode active material is applied to the positive electrode layer in the solid-state battery system. After the charge and discharge cycle, the content of Li in the positive electrode active material contained in the positive electrode layer usually changes. Among them, the content of Li can be measured using atomic molar content, but is not limited to this. Regarding "the content of Li is the initial state of the material", the initial state of the material refers to the state before being placed in the positive electrode layer. It can be understood that new materials or new substances obtained by appropriate modification on the basis of the listed positive electrode active materials are also within the scope of positive electrode active materials. The aforementioned appropriate modification refers to an acceptable modification method for the positive electrode active material, and a non-limiting example is coating modification. In the exemplary descriptions of the positive electrode active material in this application, the oxygen (O) content is generally a theoretical value. Lattice oxygen release will cause the atomic molar content of oxygen to change, and the actual O content will fluctuate. The O content can be measured by atomic molar content, but is not limited to this.

[0370] In some embodiments, the positive electrode active material layer includes a conductive agent (which may be referred to as a positive electrode conductive agent). As a non-limiting example, the positive electrode conductive agent may be a carbon conductive agent. Non-limitingly, the carbon conductive agent may include one or more of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene and carbon nanofibers. In some embodiments, the positive electrode conductive agent may include but is not limited to one or more of SP, KS-6, acetylene black, Ketjen black ECP with a branched structure, SFG-6, vapor-grown carbon fiber VGCF, carbon nanotubes (CNTs) and graphene. Non-limitingly, the weight percentage of the positive electrode conductive agent in the positive electrode active material layer may be 0 to 10 wt%, further 0 to 8 wt%, further 0 to 5 wt%, further 0.1 wt% to 3 wt%, based on the total weight of the positive electrode active material layer. The weight percentage of the positive electrode conductive agent in the positive electrode active material layer may also be 0.1 wt% to 5 wt%, 0.2 wt% to 5 wt%, 0.5 wt% to 5 wt%, 0.1 wt% to 3 wt%, etc.

[0371] In some embodiments, the positive electrode active material layer optionally includes a binder (which may be referred to as a positive electrode binder). As a non-limiting example, the positive electrode binder may include one or more of polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene terpolymer, tetrafluoroethylene-hexafluoropropylene copolymer, and fluorine-containing acrylate resin. Typically, the weight percentage of the positive electrode binder in the positive electrode active material layer may be 0 to 10 wt%, further 0 to 8 wt%, further 0.1 wt% to 5 wt%, further 1 wt% to 5 wt%, based on the total weight of the positive electrode active material layer.

[0372] Without limitation, the positive electrode active material layer may include positive electrode active particles, positive electrode electrolyte particles, a positive electrode conductive agent, and a positive electrode binder. The type and content of each component can be referred to the context of this application.

[0373] In some embodiments, the positive electrode electrolyte particles include the sulfide solid electrolyte described in the first aspect of the present application.

[0374] In some embodiments, a positive electrode membrane (a positive electrode membrane can be used as a positive electrode sheet) can be prepared in the following manner: the components for preparing the positive electrode membrane, such as positive electrode active particles, positive electrode electrolyte particles, positive electrode conductive agent, optional positive electrode binder and any other components are dry-mixed, and then the mixed material is heated, pressurized and kneaded into a mass material, which is hot rolled to form a self-supporting positive electrode sheet, and the self-supporting positive electrode sheet is hot-rolled with the positive electrode collector. The self-supporting positive electrode sheet can be compounded on at least one side (one side or two sides) of the positive electrode collector to obtain a positive electrode membrane. Without limitation, a double planetary mixer can be used for dry mixing. Without limitation, an internal mixer can be used for heating, pressurizing and kneading. Without limitation, the temperature for hot rolling can be 75°C to 85°C, further such as 78°C, 80°C, 82°C, etc. The method of assembling solid-state batteries using positive electrode membranes can be suitable for industrial mass production. A similar method can be used to prepare negative electrode membranes or negative electrode sheets.

[0375] In some embodiments, the positive electrode membrane can be prepared by the following method: the components for preparing the positive electrode membrane, such as positive electrode active particles, positive electrode electrolyte particles, positive electrode conductive agent, positive electrode binder and any other components, are dispersed in an organic solvent to form a positive electrode slurry. Further, the positive electrode slurry is coated on at least one side of the positive electrode current collector, and after drying, pressing and other processes, the positive electrode membrane can be obtained. The type of organic solvent in the positive electrode slurry can include one or more of p-xylene, trimethylbenzene, butyl butyrate, heptane, etc., and can further be p-xylene. The surface of the positive electrode current collector coated with the positive electrode slurry can be on a single surface of the positive electrode current collector or on both surfaces of the positive electrode current collector. The solid content of the positive electrode slurry can be 40wt% to 80wt%. The viscosity of the positive electrode slurry at room temperature can be adjusted to 5000mPa·s to 25000mPa·s. When coating the positive electrode slurry, the coating unit area density (single side) based on dry weight (excluding solvent) can be 15mg / cm 2 ~35mg / cm 2 The compaction density of the positive electrode membrane can be 3.0g / cm 3 ~3.6g / cm 3 , optional 3.3g / cm 3 ~3.5g / cm 3 .

[0376] The “compacted density” used in this application has a meaning well known in the art and is one of the reference indicators of material energy density. In this application, unless otherwise specified, the compacted density of an electrode layer refers to the ratio of the mass of the electrode active material layer to its volume. The compacted density of a positive electrode layer, a positive electrode sheet, a positive electrode film or a positive electrode membrane refers to the ratio of the mass of the positive electrode active material layer to its volume, and the compacted density of a negative electrode layer, a negative electrode sheet, a negative electrode film or a negative electrode membrane refers to the ratio of the mass of the negative electrode active material layer to its volume.

[0377] Compacted density = coating area density / thickness of electrode active material layer.

[0378] Coating area density = slurry dry weight / electrode active material layer area.

[0379] The double-sided thickness of the electrode active material layer corresponds to the sum of the coating surface density on both sides, and the single-sided thickness corresponds to the single-sided coating surface density; when the electrode active material layers on both sides of the current collector are basically the same, it can be calculated according to the following formula: compaction density = single-sided coating surface density / single-sided thickness of the electrode active material layer.

[0380] The “single-sided” and “double-sided” electrode active material layers refer to the positional distribution relative to the current collector.

[0381] The following is some description about the negative electrode film and the negative electrode layer.

[0382] In this application, unless otherwise specified, "negative electrode film" refers to a film that can be used as a negative electrode of a solid-state battery, including at least a negative electrode active material layer and may also include a negative electrode current collector.

[0383] The negative electrode layer can be provided by a negative electrode sheet or negative electrode membrane that can be used in solid-state batteries in the art. Alternatively, the negative electrode layer component materials can be directly pressed onto one surface of the solid electrolyte layer to form a negative electrode membrane layer. The negative electrode membrane can be combined with other films suitable for the negative electrode to form a negative electrode sheet or negative electrode layer.

[0384] The negative electrode layer can be prepared by a dry process or a wet process. For example, a dry process can be used to press the negative electrode film, which can be a negative electrode film sheet or a negative electrode film layer. For another example, a wet process can be used to coat the negative electrode film, which can be a negative electrode film layer.

[0385] The negative electrode film and the negative electrode layer each include a negative electrode active material layer, which includes negative electrode active particles containing negative electrode active materials. Without limitation, the negative electrode active material layer may include or exclude negative electrode electrolyte particles.

[0386] In some embodiments, the negative electrode active material layer includes negative electrode electrolyte particles. Further, the negative electrode electrolyte particles may include the sulfide solid electrolyte described in the first aspect of the present application.

[0387] Without limitation, the weight percentage of the negative electrode active particles or the negative electrode active material in the negative electrode active material layer may be ≥80 wt %, and further may be ≥90 wt %.

[0388] In some embodiments, the negative electrode active particles or the negative electrode active material are lithium-indium alloy (InLi alloy).

[0389] In some embodiments, the negative electrode layer is an InLi alloy film.

[0390] In some embodiments, the negative electrode active material may also be a negative electrode active material that is well known in the art and can be used for solid-state batteries. As a non-limiting example, the negative electrode active material may include one or more of the following materials: elemental silicon, elemental tin, silicon-carbon anode, silicon monoxide, graphite, and metallic lithium. However, the present application is not limited to these materials or substances, and other traditional materials that can be used as battery negative electrode active materials may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0391] In some embodiments, the negative electrode sheet or negative electrode film may include a negative electrode current collector and a negative electrode active material layer disposed on at least one surface of the negative electrode current collector, the negative electrode active material layer including a negative electrode active material. As a non-limiting example, the negative electrode current collector has two surfaces that face away from each other in the thickness direction of the negative electrode current collector, and the negative electrode active material layer is disposed on either or both of the two facing surfaces of the negative electrode current collector. In some embodiments, the negative electrode current collector may be a metal foil or a composite current collector. For example, copper foil may be used as the metal foil. In the negative electrode current collector, the composite current collector may include a polymer material base layer and a metal layer formed on at least one surface of the polymer material base layer. In the negative electrode current collector, the composite current collector may be formed by forming a metal material on a polymer material base layer. Non-limiting examples of the metal material in the negative electrode current collector may include one or more of copper, copper alloys, nickel, nickel alloys, titanium, titanium alloys, silver, and silver alloys. In the negative electrode current collector, non-limiting examples of the polymer material substrate may include one or more of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), polyethylene (PE), and the like.

[0392] In some embodiments, the negative electrode active material layer may optionally include a conductive agent, referred to as a negative electrode conductive agent. Without limitation, the negative electrode conductive agent may include one or more of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers. In the negative electrode active material layer, the weight percentage of the negative electrode conductive agent may be 0 to 10 wt %, further preferably 0 to 5 wt %, further preferably 0.1 wt % to 5 wt %, and further preferably 0.1 wt % to 3 wt %.

[0393] In some embodiments, the negative electrode active material layer may optionally include a binder (referred to as a negative electrode binder). As a non-limiting example, the negative electrode binder may include one or more of polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), a vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, a vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene terpolymer, a tetrafluoroethylene-hexafluoropropylene copolymer, and a fluorine-containing acrylate resin. In a non-limiting manner, the weight proportion of the negative electrode binder in the negative electrode active material layer may be 0 to 10 wt %, further 0 to 5 wt %, further 1 wt % to 5 wt %, and further optionally 1 wt % to 3 wt %.

[0394] In some embodiments, the negative electrode active material layer may optionally include other additives, such as a thickener (e.g., sodium carboxymethyl cellulose (CMC-Na)). The weight percentage of the other additives in the negative electrode active material layer may be 0-15 wt %, further preferably 0-10 wt %, further preferably 0-5 wt %, further preferably 0-3 wt %, and further preferably 0-2 wt %.

[0395] In some embodiments, the negative electrode membrane (the negative electrode membrane can be used as the negative electrode sheet) can be prepared in the following manner: the components for preparing the negative electrode membrane, such as negative electrode active particles, optional negative electrode electrolyte particles, negative electrode conductive agent, optional negative electrode binder and any other components are dry-mixed, and then the mixed material is heated, pressurized and kneaded into a mass material, and hot roller pressed to form a self-supporting negative electrode sheet, and the self-supporting negative electrode sheet is hot-rolled with the negative electrode collector. The self-supporting negative electrode sheet can be compounded on at least one side (one side or two sides) of the negative electrode collector to obtain a negative electrode membrane. Without limitation, a double planetary mixer can be used for dry mixing. Without limitation, an internal mixer can be used for heating, pressurizing and kneading. The method of assembling solid-state batteries using negative electrode membranes can be suitable for industrial mass production. When the negative electrode material is prepared into a negative electrode active material layer by a dry method, a negative electrode conductive agent can be set in the negative electrode material to improve the electron conductivity of the negative electrode active material layer.

[0396] In some embodiments, a negative electrode sheet or negative electrode membrane can be prepared by dispersing the components used to prepare the negative electrode sheet or negative electrode membrane, such as negative electrode active particles, optional negative electrode electrolyte particles, negative electrode conductive agent, negative electrode binder, and any other components, in a solvent (a non-limiting example of a solvent is p-xylene) to form a negative electrode slurry. Furthermore, the negative electrode slurry is coated on at least one surface of a negative electrode current collector. After drying and pressing, the negative electrode sheet or negative electrode membrane can be obtained. The negative electrode current collector surface coated with the negative electrode slurry can be a single surface of the negative electrode current collector or both surfaces of the negative electrode current collector. The solid content of the negative electrode slurry can be 30 wt% to 70 wt%, preferably 40 wt% to 60 wt%. The viscosity of the negative electrode slurry at room temperature can be adjusted to 2000 mPa·s to 10000 mPa·s, preferably 3000 mPa·s to 10000 mPa·s. When coating the negative electrode slurry, the coating unit area density (single side) based on dry weight (excluding solvent) can be 1.5 mg / cm 2 ~18mg / cm 2 , but not limited thereto. The compaction density of the negative electrode sheet or negative electrode membrane can be 1.0 g / cm 3 ~2.0g / cm 3 , optional 1.0g / cm 3 ~1.8g / cm 3 .

[0397] In a non-limiting manner, the positive electrode sheet, the solid electrolyte membrane and the negative electrode sheet can be stacked in sequence, the solid electrolyte can be placed between the positive electrode membrane and the negative electrode membrane, and the solid-state battery cell can be prepared by hot rolling.

[0398] In a non-limiting manner, the positive electrode membrane, the solid electrolyte membrane and the negative electrode membrane may be stacked in sequence, the solid electrolyte may be placed between the positive electrode membrane and the negative electrode membrane, and the solid-state battery cell may be prepared by hot rolling.

[0399] In some embodiments, the solid-state battery cell 5 includes a solid-state battery cell 52 .

[0400] In some embodiments, the solid-state battery cell is an all-solid-state battery cell.

[0401] In some embodiments, the solid-state battery cell 52 (which may be an all-solid-state battery cell) includes a positive electrode layer 200, a solid electrolyte layer 100, and a negative electrode layer 300 stacked in sequence. An example of this can be found in Figure 1 .

[0402] In some embodiments, the solid-state battery may include an outer packaging that can be used to encapsulate the solid-state battery cell.

[0403] In some embodiments, the outer packaging of the solid-state battery can be a hard shell, such as a hard plastic shell, an aluminum shell, a steel shell, etc. The outer packaging of the solid-state battery can also be a soft package, such as a bag-type soft package. The material of the soft package can be plastic. Further, non-limiting examples of plastic can include one or more of polypropylene, polybutylene terephthalate, and polybutylene succinate.

[0404] The present application has no particular restrictions on the shape of the solid-state battery cell, which can be cylindrical, square or any other shape. For example, Figure 2 The solid-state battery cell 5 is a square structure as an example.

[0405] In some embodiments, reference Figure 3 The outer packaging may include a shell 51 and a cover plate 53. The shell 51 may 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 connected to the receiving cavity, and the cover plate 53 can be covered on the opening to close the receiving cavity. The solid-state battery cell 52 is encapsulated in the receiving cavity. The number of solid-state battery cells 52 contained in the solid-state battery cell 5 can be one or more, and those skilled in the art can select according to actual needs.

[0406] The solid-state battery can be a battery module 4 or a battery pack 1 .

[0407] The battery module includes at least one solid-state battery cell. The number of solid-state battery cells contained in the battery module can be one or more, and those skilled in the art can select an appropriate number based on the application and capacity of the battery module.

[0408] Figure 4 4 is an example of a battery module. Figure 4 In the battery module 4, the plurality of solid-state battery cells 5 may be arranged in sequence along the length of the battery module 4. Of course, they may also be arranged in any other manner. The plurality of solid-state battery cells 5 may further be fixed by fasteners.

[0409] Optionally, the battery module 4 may further include a housing having a receiving space, and the plurality of solid-state battery cells 5 are received in the receiving space.

[0410] In some embodiments, the battery modules may be assembled into a battery pack. The battery pack may contain one or more battery modules. Those skilled in the art may select an appropriate number based on the application and capacity of the battery pack.

[0411] Figure 5 and Figure 6 The battery pack 1 is used as an example. Figure 5 and Figure 6The battery pack 1 may include a battery box and multiple battery modules 4 disposed in the battery box. The battery box includes an upper box body 2 and a lower box body 3. The upper box body 2 can cover the lower box body 3 and form an enclosed space for accommodating the battery modules 4. The multiple battery modules 4 can be arranged in any manner in the battery box.

[0412] In some embodiments, the electrical device includes the solid-state battery of any embodiment provided herein.

[0413] Without limitation, solid-state batteries can be used as power sources for electrical devices or as energy storage units for electrical devices. Electrical devices may include, but are not limited to, mobile devices, electric vehicles, electric trains, ships and satellites, energy storage systems, and the like. Examples of mobile devices include, but are not limited to, mobile phones and laptops; examples of electric vehicles include, but are not limited to, pure electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, electric bicycles, electric scooters, electric golf carts, electric trucks, electric motorcycles, and electric tools. The electrical device may also be used in fields such as military equipment and aerospace, and in energy storage power systems such as hydropower, thermal power, wind power, and solar power stations.

[0414] As an electrical device, a solid-state battery can be selected according to its usage requirements.

[0415] Figure 7 The example of an electric device 6 is shown. The electric device is a pure electric vehicle, a hybrid electric vehicle, or a plug-in hybrid electric vehicle. To meet the electric device's requirements for high power and high energy density of solid-state batteries, a battery pack or battery module can be used.

[0416] Another example device may be a mobile phone, a tablet computer, a laptop computer, etc. Such a device is usually required to be lightweight and thin, and may use a solid-state battery as a power source.

[0417] Below, some embodiments of the present application are described. The embodiment described below is exemplary, is only used to explain the present application, and cannot be construed as limiting the present application. In the embodiment, if no technology or conditions are indicated, it is carried out according to the description above, or according to the technology or conditions described in the document in this area, or according to the product specification. Reagents used or instruments that do not indicate manufacturers are conventional products that can be obtained commercially, or can be synthesized in a conventional manner by commercially available products.

[0418] In the following examples, room temperature refers to 20°C to 30°C.

[0419] In the following examples, unless otherwise specified, the amount of "elemental sulfur" expressed in wt% refers to the weight percentage in the sintered mixture; in the following preparation examples, unless otherwise specified, the sintered mixture is the precursor mixture; in the following preparation comparative examples, unless otherwise specified, the sintered mixture is the raw material mixture.

[0420] It should be noted that sulfide all-solid-state batteries are used as non-limiting examples of solid-state batteries in the following embodiments and examples.

[0421] 1. Preparation of sulfide solid electrolyte

[0422] Preparation Example 1. According to the chemical formula Li 10.5 Sn 1.5 P 1.5 S 12 , weigh the stoichiometric proportions of Li2S, P2S5 and SnS2 raw material powders respectively, and weigh 3wt% of sulfur element, mix them evenly to obtain a precursor mixture, place the above precursor mixture in an inert atmosphere (argon) furnace at 600°C and sinter for 8h, then crush the sintered body to obtain sulfide solid electrolyte powder.

[0423] Preparation Example 2. According to the chemical formula Li 10.7 Sn 1.7 P 1.3 S 12 , weigh the stoichiometric proportions of Li2S, P2S5 and SnS2 raw material powders respectively, and weigh 3wt% of sulfur element, mix them evenly to obtain a precursor mixture, place the above precursor mixture in an inert atmosphere (argon) furnace and sinter at 580°C for 8h, then crush the sintered body to obtain sulfide solid electrolyte powder.

[0424] Preparation Example 3. A sulfide solid electrolyte was prepared by the same method as in Preparation Example 2, except that the target chemical formula for regulating the stoichiometric ratio of the raw materials was Li 10.1 Sn 1.1 P 1.9 S 12 .

[0425] Preparation Example 4. According to the chemical formula Li 10.5 Sn 1.5 P 1.3 Sb 0.2 S 12 , weigh the stoichiometric proportions of Li2S, P2S5, Sb2S3, S and SnS2 raw material powders respectively, and weigh 3wt% of sulfur element, mix them evenly to obtain a precursor mixture, place the above precursor mixture in an inert atmosphere (argon) furnace and sinter at 580°C for 8h, and then crush the sintered body to obtain sulfide solid electrolyte powder.

[0426] Preparation Example 5. According to the chemical formula Li 10.5 Sn 1.5 P 1.1 Sb 0.4 S 12 , weigh the stoichiometric proportions of Li2S, P2S5, Sb2S3, S and SnS2 raw material powders respectively, and weigh 3wt% of sulfur element, mix them evenly to obtain a precursor mixture, place the above precursor mixture in an inert atmosphere (argon) furnace and sinter at 560°C for 8h, and then crush the sintered body to obtain sulfide solid electrolyte powder.

[0427] Example 6. A sulfide solid electrolyte was prepared by the same method as in Example 5, except that the target chemical formula for regulating the stoichiometric ratio of the raw materials was Li 10.7 Sn 1.7 P 0.9 Sb 0.4 S 12 , the sintering temperature was changed to 540℃.

[0428] Example 7. A sulfide solid electrolyte was prepared by the same method as in Example 5, except that the target chemical formula for regulating the stoichiometric ratio of the raw materials was Li 10.1 Sn 1.1 P 1.5 Sb 0.4 S 12 , the sintering temperature was changed to 570℃.

[0429] Preparation Example 8. According to the chemical formula Li 10.5 Sn 1.5 P 1.5 S 10.5 O 1.5 , weigh the stoichiometric proportions of Li2S, P2S5, P2O5 and SnS2 raw material powders respectively, and weigh 3wt% of sulfur element, mix them evenly to obtain a precursor mixture, place the above precursor mixture in an inert atmosphere (argon) furnace at 600°C and sinter for 8h, then crush the sintered body to obtain sulfide solid electrolyte powder.

[0430] Preparation Example 9. According to the chemical formula Li 10.5 Sn 1.5 P 1.5 S 9.1 O 2.9 , weigh the stoichiometric proportions of Li2S, P2S5, P2O5 and SnS2 raw material powders respectively, and weigh 3wt% of sulfur element, mix them evenly to obtain a precursor mixture, place the above precursor mixture in an inert atmosphere (argon) furnace and sinter at 620℃ for 8h, then crush the sintered body to obtain sulfide solid electrolyte powder.

[0431] Preparation Example 10. A sulfide solid electrolyte was prepared by the same method as in Preparation Example 9, except that the target chemical formula for regulating the stoichiometric ratio of the raw materials was Li 10.7 Sn 1.7 P 1.3 S 9.1 O 2.9 , the sintering temperature was changed to 560℃.

[0432] Preparation Example 11. A sulfide solid electrolyte was prepared by the same method as in Preparation Example 9, except that the target chemical formula for regulating the stoichiometric ratio of the raw materials was Li 10.1 Sn 1.1 P 1.9 S 9.1 O 2.9 , the sintering temperature was changed to 600℃.

[0433] Preparation Example 12. According to the chemical formula Li 10.2 Sn 1.5 P 1.5 S 11.7 Cl 0.3 , weigh the stoichiometric proportions of Li2S, P2S5, LiCl and SnS2 raw material powders respectively, and weigh 3wt% of sulfur element, mix them evenly to obtain a precursor mixture, place the above precursor mixture in an inert atmosphere (argon) furnace and sinter at 550°C for 8h, and then crush the sintered body to obtain sulfide solid electrolyte powder.

[0434] Preparation Example 13. According to the chemical formula Li 10 Sn 1.5 P 1.5 S 11.5 Cl 0.5 , weigh the stoichiometric proportions of Li2S, P2S5, LiCl and SnS2 raw material powders respectively, and weigh 3wt% of sulfur element, mix them evenly to obtain a precursor mixture, place the above precursor mixture in an inert atmosphere (argon) furnace and sinter at 530°C for 8h, and then crush the sintered body to obtain sulfide solid electrolyte powder.

[0435] Preparation Example 14. A sulfide solid electrolyte was prepared by the same method as in Preparation Example 13, except that the target chemical formula for regulating the stoichiometric ratio of the raw materials was Li 10.2 Sn 1.7 P 1.3 S 11.5 Cl 0.5 .

[0436] Preparation Example 15. A sulfide solid electrolyte was prepared by the same method as in Preparation Example 13, except that the target chemical formula for regulating the stoichiometric ratio of the raw materials was Li9.6 Sn 1.1 P 1.9 S 11.5 Cl 0.5 , the sintering temperature was changed to 550℃.

[0437] Preparation Example 16. According to the chemical formula Li 10.5 Sn 1.5 P 1.3 Sb 0.2 S 10.5 O 1.5 , weigh the stoichiometric proportions of Li2S, P2S5, Sb2S3, S, P2O5 and SnS2 raw material powders respectively, and weigh 3wt% of sulfur element, mix them evenly to obtain a precursor mixture, place the above precursor mixture in an inert atmosphere (argon) furnace and sinter at 580°C for 8h, and then crush the sintered body to obtain sulfide solid electrolyte powder.

[0438] Preparation Example 17. According to the chemical formula Li 10.2 Sn 1.5 P 1.3 Sb 0.2 S 11.7 Cl 0.3 , weigh the stoichiometric proportions of Li2S, P2S5, Sb2S3, S, LiCl and SnS2 raw material powders respectively, and weigh 3wt% of sulfur element, mix them evenly to obtain a precursor mixture, place the above precursor mixture in an inert atmosphere (argon) furnace and sinter at 550°C for 8h, and then crush the sintered body to obtain sulfide solid electrolyte powder.

[0439] Preparation Example 18. According to the chemical formula Li 10.2 Sn 1.5 P 1.5 S 10.2 O 1.5 Cl 0.3 , weigh the stoichiometric proportions of Li2S, P2S5, LiCl, P2O5 and SnS2 raw material powders respectively, and weigh 3wt% of sulfur element, mix them evenly to obtain a precursor mixture, place the above precursor mixture in an inert atmosphere (argon) furnace and sinter at 550°C for 8h, then crush the sintered body to obtain sulfide solid electrolyte powder.

[0440] Preparation Example 19. According to the chemical formula Li1 0.2 Sn 1.7 P 0.9 Sb 0.4 S 8.6 O 2.9 Cl 0.5, weigh Li2S, P2S5, SnS2, Sb2S3, S, LiCl, P2O5, and raw material powders in stoichiometric proportions respectively, and also weigh 3wt% of sulfur element, mix them to obtain a precursor mixture, place the above precursor mixture in an inert atmosphere (argon) furnace and sinter at 540°C for 8h, and then crush the sintered body to obtain sulfide solid electrolyte powder.

[0441] Preparation Example 20. According to the chemical formula Li 9.6 Sn 1.1 P 1.5 Sb 0.4 S 8.6 O 2.9 Cl 0.5 , weigh Li2S, P2S5, SnS2, Sb2S3, S, LiCl, P2O5, and raw material powders in stoichiometric proportions respectively, and also weigh 3wt% of sulfur element, mix them to obtain a precursor mixture, place the above precursor mixture in an inert atmosphere (argon) furnace and sinter at 540°C for 8h, and then crush the sintered body to obtain sulfide solid electrolyte powder.

[0442] Preparation Comparative Example 1. According to the chemical formula Li 10 SnP2S 12 , weigh the stoichiometric proportions of Li2S, P2S5 and SnS2 raw material powders respectively, and weigh 3wt% of sulfur element, mix them evenly to obtain a raw material mixture, place the above raw material mixture in an atmosphere (argon) furnace and sinter at 600℃ for 8h, and then crush the sintered body to obtain sulfide solid electrolyte powder.

[0443] Preparation Comparative Example 2. According to the chemical formula Li 10 SnP 1.8 Sb 0.2 S 12 , weigh the stoichiometric proportions of Li2S, P2S5, Sb2S3, S and SnS2 raw material powders respectively, and weigh 3wt% of sulfur element, mix them evenly to obtain a raw material mixture, place the above raw material mixture in an atmosphere (argon) furnace and sinter at 580°C for 8h, and then crush the sintered body to obtain sulfide solid electrolyte powder.

[0444] Preparation Comparative Example 3. According to the chemical formula Li 10 SnP2S 10.5 O 1.5 , weigh the stoichiometric proportions of Li2S, P2S5, P2O5 and SnS2 raw material powders respectively, and weigh 3wt% of sulfur element, mix them evenly to obtain a raw material mixture, place the above raw material mixture in an atmosphere (argon) furnace and sinter at 600℃ for 8h, then crush the sintered body to obtain sulfide solid electrolyte powder.

[0445] Preparation Comparative Example 4. According to the chemical formula Li 9.7 SnP2S 11.7 Cl 0.3 , weigh the stoichiometric proportions of Li2S, P2S5, LiCl and SnS2 raw material powders respectively, and weigh 3wt% of sulfur element, mix them evenly to obtain a raw material mixture, place the above raw material mixture in an atmosphere (argon) furnace and sinter at 550°C for 8h, and then crush the sintered body to obtain sulfide solid electrolyte powder.

[0446] Preparation Comparative Example 5. A cation-substituted element is included, but the cation-substituted element does not include either Sb or Sn.

[0447] According to the chemical formula Li 10.5 Sn 1.5 P 1.3 Ge 0.2 S 12 , weigh the stoichiometric proportions of Li2S, P2S5, GeS2, S and SnS2 raw material powders respectively, and weigh 3wt% of sulfur element, mix them evenly to obtain a raw material mixture, place the above raw material mixture in an inert atmosphere (argon) furnace and sinter at 580°C for 8h, then crush the sintered body to obtain sulfide solid electrolyte powder.

[0448] Compared with Preparation Example 4, Comparative Example 5 was prepared by replacing the Sb element with the Ge element.

[0449] Preparation Comparative Example 6. An anion-substituting element is included, but the anion-substituting element does not include either O element or Cl element.

[0450] According to the chemical formula Li 10.2 Sn 1.5 P 1.5 S 11.7 Br 0.3 , weigh the stoichiometric proportions of Li2S, P2S5, LiBr and SnS2 raw material powders respectively, and weigh 3wt% of sulfur element, mix them evenly to obtain a raw material mixture, place the above raw material mixture in an inert atmosphere (argon) furnace and sinter at 580°C for 8h, then crush the sintered body to obtain sulfide solid electrolyte powder.

[0451] Compared with Preparation Example 12, Comparative Example 6 was prepared by replacing the Cl element with the Br element.

[0452] In Preparation Examples 1-20, when a cation-substituted element is involved, at least one of Sb and Sn is used as an example, and when an anion-substituted element is involved, one or both of O and Cl are used as examples.

[0453] The target chemical formulas of the sulfide solid electrolytes prepared in Preparation Examples 1-20 and Comparative Examples 1-6 can be found in Table 1. The atomic ratios of the following elements in the LGPS type crystal phase were calculated based on the chemical formula in Table 1. The atomic ratios of the following elements in the LGPS type crystal phase can be found in Table 2: The atomic ratios of the cation-substituted element and the P element (R Y / P ), the atomic number ratio of the anion substitution element and the S element (R N / S ), the atomic number ratio of Sn element and S element (R Sn / S ), the atomic number ratio of Sn element and P element (R Sn / P ), the atomic number ratio of Sb element and S element (R Sb / S ), the atomic number ratio of Sb and P elements (R Sb / P ), the atomic number ratio of the sum of Sn and Sb elements to S element (R (Sn+Sb) / S ), the atomic number ratio of the sum of Sn and Sb elements to P element (R (Sn+Sb) / P ), the atomic number ratio of O element and S element (R O / S ) and the atomic ratio of Cl and S (R Cl / S ), see also the definitions described above.

[0454] In the preparation of Comparative Example 5, the atomic ratio of Ge element to S element is denoted as R Ge / S The atomic ratio of Ge and P is denoted as R Ge / P The atomic ratio of the sum of Sn and Ge to S is denoted as R (Sn+Ge) / S The atomic ratio of the sum of Sn and Ge elements to P is denoted as R (Sn+Ge) / P .

[0455] In the preparation of Comparative Example 6, R Br / S Indicates the atomic ratio of bromine (Br) and sulfur.

[0456] Table 1. Target chemical formulas of sulfide solid electrolytes prepared in Preparation Examples 1-20 and Comparative Examples 1-6

[0457]

[0458] Table 2.

[0459]

[0460]

[0461] According to Table 2, R Y / P Numerically equal to R Sb / P , R N / S Numerically equal to R O / S and R Cl / S sum.

[0462] In the following examples, unless otherwise specified, operations or reaction steps involving a sulfide solid electrolyte material as a raw material were carried out in an argon atmosphere.

[0463] In the following examples, unless otherwise specified, the positive electrode active particles NCM 811 Powder D v 50 is 4μm (positive electrode active material is NCM 811 ), D of sulfide solid electrolyte Li6PS5Cl v 50 is 1μm.

[0464] In this application, unless otherwise stated, D v 50 represents the particle size corresponding to when the cumulative volume distribution percentage of the multi-particle mixture reaches 50%.

[0465] D v 50 tests:

[0466] In the following examples and comparative examples, the D v 50 The following method was used for testing and confirmation: Equipment model: Malvern 2000 (MasterSizer 2000) laser particle size analyzer, reference standard process: GB / T19077-2016 / ISO 13320:2009, specific test process: take an appropriate amount of the sample to be tested (the sample concentration is guaranteed to be 8%-12% (w / v) shading), add 20mL of p-xylene (when testing sulfide solid electrolytes, a dispersant ammonium polycarboxylate is also added), and at the same time, ultraviolet light is applied for 5min (53KHz / 120W) to ensure that the sample is completely dispersed, and then the sample is measured according to GB / T19077-2016 / ISO13320:2009 standard.

[0467] 2. Preparation of a solid electrolyte layer provided with a sulfide solid electrolyte and a solid-state battery (all-solid-state secondary battery, sulfide all-solid-state battery) provided in this application.

[0468] 1. Preparation of solid electrolyte membrane (solid electrolyte membrane form)

[0469] Examples 1-20 (corresponding to the sulfide solid electrolyte powders of Preparation Examples 1-20, respectively):

[0470] In an argon atmosphere, the sulfide solid electrolyte powder (prepared in Preparation Example 1-20) was pressed into a dense solid electrolyte membrane at 360 MPa.

[0471] In an argon atmosphere, NCM811 powder, sulfide solid electrolyte Li6PS5Cl, and conductive carbon fiber (VGCF) were manually ground in a mortar at a weight ratio of 70:28:2 for 10 minutes until they were evenly mixed to obtain a composite positive electrode powder. The composite positive electrode powder was weighed and evenly spread on one side of the solid electrolyte membrane. It was cold pressed into a sheet at a pressure of 420MPa and maintained at this pressure for 5 minutes to form a composite membrane consisting of a positive electrode layer and a solid electrolyte layer. InLi alloy was stacked on the other side of the solid electrolyte membrane as the negative electrode layer to assemble an all-solid-state battery. At this time, the solid electrolyte membrane served as the solid electrolyte layer and the positive electrode membrane served as the positive electrode layer.

[0472] Comparative Examples 1-6:

[0473] A method substantially the same as that of Example 1 was used, except that the sulfide solid electrolyte powder used to prepare the solid electrolyte membrane was replaced by the sulfide solid electrolyte powder prepared in Comparative Examples 1-6.

[0474] 3. Preparation of a positive electrode layer provided with a sulfide solid electrolyte and a solid-state battery (all-solid-state secondary battery, sulfide all-solid-state battery) provided in this application.

[0475] Examples P1 to P20 (corresponding to the sulfide solid electrolyte powders of Preparation Examples 1-20, respectively):

[0476] In an argon atmosphere, the positive electrode active particles NCM811 powder, sulfide solid electrolyte powder (prepared in Preparation Example 1-20, as positive electrode electrolyte particles), and conductive carbon fibers (VGCF, as a positive electrode conductive agent) were manually ground in a mortar at a weight ratio of 70:28:2 for 10 minutes until they were evenly mixed to obtain a composite positive electrode powder.

[0477] In an argon atmosphere, the sulfide solid electrolyte powder Li6PS5Cl was pressed into a dense solid electrolyte membrane under 360MPa.

[0478] The composite cathode powder was weighed and evenly spread on one side of the solid electrolyte membrane. The membrane was then cold-pressed into a sheet at 420 MPa for 5 minutes, forming a composite membrane consisting of a cathode layer and a solid electrolyte layer. An InLi alloy was layered on the other side of the solid electrolyte membrane as the anode layer to assemble the all-solid-state battery. In this case, the solid electrolyte membrane served as the solid electrolyte layer, and the cathode membrane served as the cathode layer.

[0479] Comparative Example P1.

[0480] The all-solid-state battery was prepared by the same method as in Example P3, except that the cathode electrolyte particles in the composite cathode powder were replaced with Li 10 SnP2S 12.

[0481] 4. Preparation of a negative electrode layer provided with a sulfide solid electrolyte and a solid-state battery (all-solid-state secondary battery, sulfide all-solid-state battery) provided in this application.

[0482] Examples N1 to N20 (corresponding to the sulfide solid electrolyte powders of Preparation Examples 1-20, respectively):

[0483] In an argon atmosphere, the sulfide solid electrolyte powder Li6PS5Cl was pressed into a dense solid electrolyte membrane under 360MPa.

[0484] In an argon atmosphere, NCM811 powder, sulfide solid electrolyte Li6PS5Cl, and conductive carbon fiber (VGCF) were manually ground in a mortar at a weight ratio of 70:28:2 for 10 minutes until uniformly mixed to obtain a composite cathode powder. The composite cathode powder was weighed and evenly spread on one side of a solid electrolyte membrane. The membrane was then cold-pressed into a sheet at a pressure of 420 MPa for 5 minutes, forming a composite membrane consisting of a cathode layer and a solid electrolyte layer.

[0485] In an argon atmosphere, the negative electrode active particles Si powder, sulfide solid electrolyte powder (prepared in Preparation Example 1-20, as the negative electrode electrolyte particles) and the negative electrode binder PVDF were dispersed in a solvent p-xylene (solid content 60 wt%) at a weight ratio of 80:17:3. The coating density was 2.5 mg / cm2 based on the dry weight (excluding the solvent). 2 Coated on the other side of the solid electrolyte layer in the composite membrane and dried to form a negative electrode layer, an all-solid-state battery is obtained, which includes a positive electrode layer (corresponding to the positive electrode membrane), a solid electrolyte layer (corresponding to the solid electrolyte membrane) and a negative electrode layer (corresponding to the negative electrode membrane) stacked in sequence.

[0486] Comparative Example N1.

[0487] The all-solid-state battery was prepared by the same method as in Example N3, except that the negative cathode electrolyte particles in the negative electrode layer were replaced with Li 10 SnP2S 12 .

[0488] The preparation parameters and test results of some examples and comparative examples in Parts 2, 3 and 4 can be found in Table 4.

[0489] 5. Material testing and analysis

[0490] (1) Testing and analysis methods

[0491] 1. Elemental analysis

[0492] The element types and proportions of the sulfide solid electrolyte were analyzed using an inductively coupled plasma spectrometer (ICP instrument) to determine its chemical formula.

[0493] Test instrument: ThermoFisher ICAP Pro.

[0494] 2. Crystal phase analysis

[0495] X-ray diffraction (XRD) patterns are used to determine whether the sulfide solid electrolyte includes LGPS type crystal phase and the amount of impurity phase.

[0496] Sample to be tested: sulfide solid electrolyte powder.

[0497] Test instrument: Bruker-D8 advance. Cu target Kα1 radiation was used, with a wavelength λ of 0.15406 nm. The X-ray tube was controlled at 40 kV and 40 mA, with a 2θ scanning range of 10° to 80° and a 2θ scanning rate of 0.02° / s.

[0498] Analytical method: According to Li 10 GeP2S 12 The comparative analysis of the XRD standard spectrum confirms whether the sulfide solid electrolyte to be tested includes the LGPS type crystal phase.

[0499] 3. Hydrogen sulfide (H2S) release test

[0500] Sample to be tested: sulfide solid electrolyte powder.

[0501] Test method: 100mg of the solid electrolyte powder to be tested is evenly spread on a 5cm diameter culture dish in a -55°C dew point environment. The culture dish containing the solid electrolyte powder is then placed in a 50L box via a sealed transfer box. The sealed transfer box containing the solid electrolyte powder culture dish is quickly opened in the box and the 50L box is sealed. A hydrogen sulfide sensor (PGM-2500) is placed in the box to record the cumulative value of hydrogen sulfide in the 50L box in real time. The reaction continues until the detection value of the hydrogen sulfide sensor no longer increases, indicating that the electrolyte has completely reacted with the water molecules in the box. At the same time, a fan with a blade diameter of 8cm is placed in the box. Since the density of hydrogen sulfide is greater than that of air, the fan can prevent the hydrogen sulfide gas from settling and ensure that the hydrogen sulfide gas in the 50L box is evenly distributed, making the hydrogen sulfide gas concentration test highly reliable. Before the test, the 50L box was in an environment with a relative humidity of 70% RH.

[0502] The sulfide solid electrolyte powders prepared in Preparation Examples 1-20 correspond to Test Examples 1-20 respectively; the sulfide solid electrolyte powders prepared in Preparation Comparative Examples 1-6 correspond to Test Comparative Examples 1-6 respectively; the test results can be found in Table 3 "Hydrogen sulfide release amount".

[0503] 4. Ionic conductivity test

[0504] The ionic conductivity was measured by electrochemical impedance spectroscopy (EIS).

[0505] Sample to be tested: Sulfide solid electrolyte powder

[0506] Preparation of test samples: 120 mg of the solid electrolyte powder to be tested was poured into a tablet pressing mold with a diameter of 10 mm, and the electrolyte powder was pressed into a dense disc at 360 MPa to obtain a solid electrolyte membrane as a test sample.

[0507] Test method: The prepared solid electrolyte membrane was clamped in a mold with a 10mm diameter cylindrical stainless steel current collector at 120MPa, and then the current collector was connected to the electrochemical workstation. 6 Electrochemical impedance spectroscopy (EIS) is performed on the electrolyte sheet in the range of Hz to 10Hz. The intersection of the curve from the high frequency band to the low frequency band in the electrochemical impedance spectrum and the Z' axis is recorded as the resistance value R. The ionic conductivity (σ) can be calculated using formula (1):

[0508]

[0509] Where d is the thickness of the solid electrolyte membrane, and A is the contact area between the electrolyte sheet and the current collector.

[0510] The sulfide solid electrolyte powders prepared in Preparation Examples 1-20 correspond to Test Examples 1-20 respectively; the sulfide solid electrolyte powders prepared in Preparation Comparative Examples 1-6 correspond to Test Comparative Examples 1-6 respectively; the test results can be found in Table 3 "Ionic Conductivity".

[0511] 5. Battery cycle performance test

[0512] The assembled battery to be tested was first activated by charging and discharging at 0.1C for 3 cycles, and then the battery was charged and discharged at 0.33C for 200 cycles to calculate the battery's cycle capacity retention rate. The battery voltage test window is 2.8~4.3Vvs.Li + / Li (for lithium potential, active ions are Li + ), the battery was tested at 25±3°C, where 1C = 200 mA / g. The test results can be found in Table 4, "200-cycle capacity retention, 0.33C".

[0513] (2) Test results analysis

[0514] 1. Elemental analysis

[0515] ICP test confirmed that the chemical formula of the sulfide solid electrolyte prepared in each preparation example 1-20 and each preparation comparative example 1-6 is basically consistent with the target chemical formula. Taking Example 1 as an example, the target sulfide solid electrolyte Li 10.5 Sn 1.5 P 1.5 S 12 The actual test results of the elemental composition are: the atomic number ratio of Li:Sn:P:S is 10.52:1.49:1.48:11.89.

[0516] 2. According to the XRD analysis results, the sulfide solid electrolytes prepared in each of Preparation Examples 1-20 and Comparative Examples 1-6 all formed LGPS type crystal phases. In addition, the impurity content of each preparation example was relatively low. As an example, the X-ray diffraction (XRD) patterns of the sulfide solid electrolytes prepared in Preparation Example 1 and Comparative Example 1 can be found at Figure 8 .

[0517] 3. Hydrogen sulfide release and ion conductivity

[0518] The test results of hydrogen sulfide release and ion conductivity of the sulfide solid electrolytes prepared in Preparation Examples 1-20 and Comparative Preparation Examples 1-6 can be found in Table 3.

[0519] Compared with the preparation of comparative examples 1-4, the sulfide solid electrolyte of preparation example 1-20 meets the following characteristics: (1) the atomic number ratio of Sn element to S element (R Sn / S ) is greater than 1 / 12; (2) the atomic number ratio of Sn element to P element (R Sn / P ) is greater than 1 / 2.

[0520] Compared with Comparative Preparation Examples 1-4, the sulfide solid electrolytes prepared in Preparation Examples 1-20 have significantly reduced hydrogen sulfide release and also have good ionic conductivity.

[0521] In each preparation example, the lower amount of hydrogen sulfide released indicates that the sulfide solid electrolyte has better chemical stability. In addition, the lower impurity content is also beneficial to improving the ionic conductivity of the sulfide solid electrolyte.

[0522] The LGPS-type crystal phase of the sulfide solid electrolyte of Test Comparative Example 5 includes a cationic substitution element, but the cationic substitution element does not include either Sb or Sn, and the cationic substitution element is Ge. Compared with Test Example 4, the hydrogen sulfide release amount of Test Comparative Example 5 is significantly increased, and the ionic conductivity is also decreased.

[0523] The LGPS-type crystal phase of the sulfide solid electrolyte of Test Comparative Example 6 includes an anion substitution element, but the anion substitution element does not include either O element or Cl. The anion substitution element is Br. Compared with Test Example 12, the hydrogen sulfide release amount of Test Comparative Example 6 is significantly increased.

[0524] 4. Battery cycle performance

[0525] The solid-state batteries prepared in Examples 1-20, Examples P1-P20, and Examples N1-N20 all had good cycle performance. Specifically, Examples 1-20 had the sulfide solid electrolyte provided in the first aspect of this application provided in the solid electrolyte layer, Examples P1-P20 had the sulfide solid electrolyte provided in the first aspect of this application provided in the positive electrode layer, and Examples N1-N20 had the sulfide solid electrolyte provided in the first aspect of this application provided in the negative electrode layer.

[0526] As an example, relative to Examples 1-20, the sulfide solid electrolyte provided in the first aspect of the present application is not provided in the solid electrolyte layer of Comparative Example 1, and the cycle performance is significantly deteriorated; relative to Examples 4, 8 and 12, the sulfide solid electrolyte provided in the first aspect of the present application is not provided in the solid electrolyte layer of Comparative Examples 2-4, and the cycle performance is significantly deteriorated; relative to Example 4, the sulfide solid electrolyte provided in the first aspect of the present application is not provided in Comparative Example 5, and the cycle performance is significantly deteriorated; relative to Example 2, the sulfide solid electrolyte provided in the first aspect of the present application is not provided in Comparative Example 6, and the cycle performance is significantly deteriorated.

[0527] As an example, compared with Examples P3 and P19, the positive electrode layer of Comparative Example P1 does not contain the sulfide solid electrolyte provided by the first aspect of the present application, and the cycle performance is significantly deteriorated.

[0528] As an example, compared with Example N3, the negative electrode layer of Comparative Example N1 does not contain the sulfide solid electrolyte provided by the first aspect of the present application, and the cycle performance is significantly deteriorated.

[0529] Table 3.

[0530]

[0531]

[0532] Table 4.

[0533]

[0534] The description of each embodiment above tends to emphasize the differences between the embodiments, and the same or similar aspects can be referenced to each other. For the sake of brevity, this article will not go into details. The technical features of the embodiments described above can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification. It should be noted that the present application is not limited to the above-mentioned embodiments. The above-mentioned embodiments are only examples. Within the scope of the technical solution of this application, embodiments with essentially the same composition as the technical idea and the same effect are included in the technical scope of this application. The embodiments described above only express several embodiments of the present application, and the description is relatively detailed, but it cannot be understood as a limitation on the scope of the patent. In addition, without departing from the scope of the main purpose of this application, other methods of applying various modifications that can be thought of by those skilled in the art to the embodiments and combining some of the constituent elements in the embodiments are also included in the scope of this application.

Claims

1. A sulfide solid electrolyte, characterized in that: Including LGPS type crystal phase; The LGPS type crystal phase includes Li, Sn, P and S elements, wherein the atomic number ratio of Sn to S is greater than 1 / 12, and the atomic number ratio of Sn to P is greater than 1 / 2; The LGPS type crystal phase includes or excludes cationic substitution elements, and also includes or excludes anionic substitution elements; When the LGPS type crystal phase includes a cationic substitution element, the cationic substitution element includes Sb element; When the LGPS type crystal phase includes an anion substitution element, the anion substitution element includes at least one of an O element and a Cl element.

2. The sulfide solid electrolyte according to claim 1, characterized in that The LGPS type crystalline phase satisfies one or more of the following characteristics: In the LGPS type crystal phase, the atomic ratio of the cationic substitution element and the P element is recorded as R Y / P , 0≤R Y / P ≤4 / 9, optionally, 0 <R Y / P ≤4 / 9, further optionally, 2 / 14≤R Y / P ≤3 / 11; In the LGPS type crystal phase, the atomic ratio of the anion substitution element and the S element is recorded as R N / S , 0≤R N / S ≤34 / 86, optionally, 0 <R N / S ≤34 / 86, further optionally, 18 / 102≤R N / S ≤29 / 91.

3. The sulfide solid electrolyte according to claim 1 or 2, characterized in that The LGPS type crystalline phase satisfies one or more of the following characteristics: The atomic number ratio of Sn element to S element is greater than or equal to 11 / 120; The atomic number ratio of the Sn element to the S element is less than or equal to 17 / 86, optionally, greater than or equal to 14 / 120 and less than or equal to 16 / 91; The atomic number ratio of Sn element to P element is greater than or equal to 11 / 19; The atomic number ratio of the Sn element to the P element is less than or equal to 17 / 9, and optionally, greater than or equal to 14 / 16 and less than or equal to 16 / 10.

4. The sulfide solid electrolyte according to any one of claims 1 to 3, characterized in that The LGPS type crystal phase includes Sb element; optionally, the atomic number ratio of Sb element to S element is greater than 0 and less than or equal to 4 / 86, and further optionally, greater than or equal to 2 / 120 and less than or equal to 3 / 91; Optionally, the atomic number ratio of the Sb element to the P element is greater than 0 and less than or equal to 4 / 9, and further optionally, greater than or equal to 2 / 14 and less than or equal to 3 / 11; Optionally, the atomic number ratio of the sum of the Sn element and the Sb element to the S element is greater than 1 / 12 and less than or equal to 21 / 86, further optionally, greater than or equal to 11 / 120 and less than or equal to 21 / 86, and further optionally, greater than or equal to 16 / 120 and less than or equal to 19 / 91; Optionally, the atomic number ratio of the sum of Sn element and Sb element to P element is greater than 1 / 2 and less than or equal to 21 / 9, further optionally, greater than or equal to 11 / 19 and less than or equal to 21 / 9, and further optionally, greater than or equal to 16 / 14 and less than or equal to 19 / 11.

5. The sulfide solid electrolyte according to any one of claims 1 to 4, characterized in that The LGPS type crystal phase includes at least one of an O element and a Cl element; Optionally, the LGPS type crystal phase includes O element, and further optionally, the atomic number ratio of O element to S element is greater than 0 and less than or equal to 29 / 86; Optionally, the atomic number ratio of the O element to the S element is greater than or equal to 0 and less than or equal to 29 / 86, and further optionally, greater than or equal to 15 / 105 and less than or equal to 20 / 91; Optionally, the LGPS type crystal phase includes Cl element, and further optionally, the atomic number ratio of Cl element to S element is greater than 0 and less than or equal to 5 / 86; Optionally, the atomic number ratio of the Cl element to the S element is greater than or equal to 0 and less than or equal to 5 / 86, and further optionally, greater than or equal to 3 / 117 and less than or equal to 4 / 91.

6. The sulfide solid electrolyte according to any one of claims 1 to 5, characterized in that The LGPS type crystal phase includes or excludes the Sb element, includes or excludes the O element, and includes or excludes the Cl element; The atomic number ratio of Li, Sn, P, Sb, S, O and Cl is (10+xm):(1+x):(2-xy):y:(12-zm):z:m; <x≤0.7,0≤y≤0.4,0≤z≤2.9,0≤m≤0.5。 7. The sulfide solid electrolyte according to claim 6, characterized in that The chemical formula of the LGPS type crystal phase is Li 10+x-m Sn 1+x P 2-x-y Sb y S 12-z-m O z Cl m .

8. The sulfide solid electrolyte according to claim 6 or 7, characterized in that The LGPS type crystalline phase satisfies one or more of the following characteristics: (z+m)>0, optionally, 0<(z+m)≤3.4, further optionally, 1.8≤(z+m)≤3.4; 0.1≤x≤0.7, optionally, 0.4≤x≤0.6; 0.2≤y≤0.4, optionally, 0.2≤y≤0.3; 1.5≤z≤2.9, optionally, 1.5≤z≤2.5; 0.3≤m≤0.5, optionally, 0.3≤m≤0.

4.

9. The sulfide solid electrolyte according to claim 6 or 7, characterized in that The LGPS type crystalline phase satisfies one, any two or three of the following characteristics: y＝0； z＝0； m＝0。 10. The sulfide solid electrolyte according to claim 6 or 7, characterized in that y=0,z=0,m=0.

11. The sulfide solid electrolyte according to claim 6 or 7, characterized in that 0 <y≤0.4,z=0,m=0。 12. The sulfide solid electrolyte according to claim 6 or 7, characterized in that y=0,0 <z≤2.9,m=0。 13. The sulfide solid electrolyte according to claim 6 or 7, characterized in that y=0,z=0,0 <m≤0.5。 14. The sulfide solid electrolyte according to claim 1 or 2, characterized in that The LGPS type crystal phase includes one or more compounds represented by the following chemical formula: Li 10.5 Sn 1.5 P 1.5 S 12 、Li 10.5 Sn 1.5 P 1.3 Sb 0.2 S 12 、Li 10.5 Sn 1.5 P 1.5 S 10.5 O 1.5 、Li 10.2 Sn 1.5 P 1.5 S 11.7 Cl 0.3 、Li 10.5 Sn 1.5 P 1.3 Sb 0.2 S 10.5 O 1.5 、Li 10.2 Sn 1.5 P 1.3 Sb 0.2 S 11.7 Cl 0.3 He Li 10.2 Sn 1.5 P 1.5 S 10.2 O 1.5 Cl 0.3 .

15. The sulfide solid electrolyte according to any one of claims 1 to 14, characterized in that The 2θ (°) diffraction angle in the X-ray diffraction pattern of the sulfide solid electrolyte has a characteristic peak consistent with the LGPS type crystal phase.

16. The sulfide solid electrolyte according to claim 15, characterized in that The X-ray diffraction pattern of the sulfide solid electrolyte satisfies at least one of the following characteristics: The 2θ (°) diffraction angle in the X-ray diffraction pattern of the sulfide solid electrolyte has peaks at 14.6±δ°, 17.4±δ°, 20.2±δ°, 20.5±δ°, 24.0±δ°, 26.9±δ°, 29.5±δ°, 32.6±δ°, 36.5±δ°, 41.5±δ° and 47.3±δ°, wherein δ is 0.2 or 0.1; The X-ray diffraction pattern of the sulfide solid electrolyte is obtained by using Cu Kα radiation; The X-ray diffraction pattern of the sulfide solid electrolyte is obtained by powder X-ray diffraction testing.

17. A method for preparing a sulfide solid electrolyte, characterized in that: It includes the following steps: A precursor mixture including Li2S, P2S5, SnS2 and elemental sulfur is provided according to a required raw material stoichiometric ratio, wherein the precursor mixture includes or does not include a cation source, and the precursor mixture includes or does not include an anion source; wherein the cation source is a raw material for providing a cation-substituting element, and the anion source is a raw material for providing an anion-substituting element; when the sulfide solid electrolyte includes a cation-substituting element, the cation-substituting element includes Sb; when the sulfide solid electrolyte includes an anion-substituting element, the anion-substituting element includes at least one of O and Cl; when the sulfide solid electrolyte contains Sb, the precursor mixture includes Sb2S3; when the sulfide solid electrolyte contains O, the precursor mixture includes P2O5; when the sulfide solid electrolyte contains Cl, the precursor mixture includes LiCl; The precursor mixture is sintered in an inert atmosphere to prepare a sulfide solid electrolyte including an LGPS type crystal phase; in the LGPS type crystal phase, the atomic number ratio of the Sn element to the S element is greater than 1 / 12, and the atomic number ratio of the Sn element to the P element is greater than 1 / 2.

18. The method for preparing a sulfide solid electrolyte according to claim 17, wherein: Meet one or more of the following characteristics: The weight percentage of the sulfur element relative to the precursor mixture is 2.9 wt% to 3.1 wt%; The inert atmosphere is an argon atmosphere; In the step of sintering the precursor mixture in an inert atmosphere, the sintering temperature is 520° C. to 620° C., and can be optionally 530° C. to 620° C.; The prepared sulfide solid electrolyte is the sulfide solid electrolyte described in any one of claims 1 to 16.

19. A solid electrolyte membrane, characterized in that The invention comprises at least one of the sulfide solid electrolyte according to any one of claims 1 to 16 and the sulfide solid electrolyte prepared by the preparation method according to claim 17 or 18.

20. An electrode plate, characterized in that: The invention comprises an electrode active material layer, wherein the electrode active material layer comprises an electrode active substance and at least one of the sulfide solid electrolyte according to any one of claims 1 to 16 and the sulfide solid electrolyte prepared by the preparation method according to claim 17 or 18.

21. The electrode plate according to claim 20, characterized in that: The electrode sheet is a positive electrode sheet, the electrode active material layer is referred to as a positive electrode active material layer, and the electrode active substance is referred to as a positive electrode active substance; Alternatively, the electrode plate is a negative electrode plate, the electrode active material layer is recorded as a negative electrode active material layer, and the electrode active substance is recorded as a negative electrode active substance.

22. A solid-state battery, characterized in that: The present invention comprises at least one of the sulfide solid electrolyte according to any one of claims 1 to 16, the sulfide solid electrolyte prepared by the preparation method according to claim 17 or 18, the solid electrolyte membrane according to claim 19, and the electrode plate according to claim 20 or 21.

23. The solid-state battery according to claim 22, characterized in that The solid-state battery is a sulfide all-solid-state battery.

24. An electrical device, characterized in that: It comprises at least one of the sulfide solid electrolyte according to any one of claims 1 to 16, the sulfide solid electrolyte prepared by the preparation method according to claim 17 or 18, the solid electrolyte membrane according to claim 19, the electrode plate according to claim 20 or 21, and the solid-state battery according to claim 22 or 23.

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