Sulfide solid electrolyte and preparation method therefor, solid electrolyte membrane, electrode sheet, solid-state battery and electric device

Abstract

The present application relates to a sulfide solid electrolyte and a preparation method therefor, a solid electrolyte membrane, an electrode sheet, a solid-state battery and an electric device. The sulfide solid electrolyte comprises an LGPS-type crystal phase, and the LGPS type crystal phase comprises Li, Sn, P and S, 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.

Description

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

[0001] Related Applications

[0002] The present application claims priority to the Chinese patent application No. CN2024104515142, filed on April 15, 2024, entitled "Sulfide solid electrolyte, preparation method thereof, solid electrolyte membrane, electrode sheet, solid-state battery and electric device", the contents of which are hereby incorporated by reference in its entirety. TECHNICAL FIELD

[0003] The present application relates to the technical field of secondary batteries, further relates to the technical field of solid-state batteries, and more further relates to a sulfide solid electrolyte, a preparation method thereof, a solid electrolyte membrane, an electrode sheet, a solid-state battery and an electric device. BACKGROUND

[0004] The statements herein are provided only to complement the background information of the present application and do not necessarily constitute the prior art.

[0005] Solid-state batteries introduce non-flammable solid electrolytes to replace organic electrolytes in traditional liquid secondary batteries, which greatly improves the safety of the batteries. Among a large number of solid electrolyte materials, sulfide solid electrolytes have become the most practical and industrialized solid electrolyte material due to their ultra-high ionic conductivity and excellent mechanical properties. However, the stability of sulfide solid electrolytes is poor, and they can easily react to release hydrogen sulfide toxic gas when exposed to moisture in the air, which seriously restricts the practical application of sulfide solid electrolytes. SUMMARY

[0006] According to various embodiments and various examples of the present application, the present application provides a sulfide solid electrolyte, a preparation method thereof, a solid electrolyte membrane, an electrode sheet, a solid-state battery and an electric device. The sulfide solid electrolyte significantly reduces the release of hydrogen sulfide of the sulfide electrolyte in a water-containing environment.

[0007] In a first aspect of the present application, a sulfide solid electrolyte is provided, comprising a LGPS-type crystal phase;

[0008] The LGPS-type crystal phase comprises Li elements, Sn elements, P elements and S elements, wherein the atomic number ratio of Sn elements and S elements is greater than 1 / 12, and the atomic number ratio of Sn elements and P elements is greater than 1 / 2;

[0009] The LGPS-type crystal phase comprises or does not comprise cation substitution elements, and further comprises or does not comprise anion substitution elements;

[0010] When the LGPS-type crystal phase includes a cation-substituted element, the cation-substituted element includes an Sb element.

[0011] When the LGPS-type crystal phase includes an anion-substituted element, the anion-substituted element includes at least one of an O element and a Cl element.

[0012] The sulfide solid electrolyte includes an LGPS-type crystal phase, and by controlling the atomic number ratio of a tin (Sn) element to a sulfur (S) element to be greater than 1 / 12 (one twelfth) and controlling the atomic number ratio of the Sn element to a P element to be greater than 1 / 2 (one half), the content of a phosphorus (P) element can be reduced. Based on the Hard Soft Acid Base (HSAB) theory, compared to the bonding strength of a hard acid (P) and a soft base (S), a soft acid (Sn) and a soft base (S) can form a stronger chemical bond, which is not easily broken by water molecules, and can significantly reduce the release amount of hydrogen sulfide gas of the sulfide solid electrolyte in a water-containing environment (such as air).

[0013] The sulfide solid electrolyte can further reduce the release amount of hydrogen sulfide gas by using one or both of cation substitution and anion substitution. On the one hand, cation substitution can be used to increase the content of either the Sn element or the Sb element in the material structure, and both can reduce the content of the P element. Based on the Hard Soft Acid Base (HSAB) theory, compared to the bonding strength of a hard acid (P) and a soft base (S), a soft acid (Sn or Sb) and a soft base (S) have a stronger chemical bond, which is not easily broken by water molecules, and can reduce the release amount of hydrogen sulfide gas of the sulfide electrolyte in a water-containing environment. On the other hand, anion substitution can be used to replace the S element with either of an O element and a Cl element, both of which can reduce the content of the S element in the material structure and reduce the release amount of hydrogen sulfide gas. Cation substitution and anion substitution can be combined to better reduce the release amount of hydrogen sulfide gas.

[0014] In some embodiments, the LGPS-type crystal phase satisfies one or more of the following characteristics:

[0015] In the LGPS-type crystal phase, the atomic number ratio of the cation-substituted element to the P element is denoted as R Y / P , 0≤R Y / P ≤4 / 9, optionally, 0 Y / P ≤4 / 9, further optionally, 2 / 14≤R Y / P ≤3 / 11.

[0016] In the LGPS-type crystal phase, the atomic number ratio of the anion-substituted element to the S element is denoted as R N / S , 0≤R N / S ≤34 / 86, optionally, 0 N / S≤ 34 / 86, further optionally, 18 / 102 ≤ R N / S ≤ 29 / 91.

[0017] by controlling at least one of the atomic number ratio of the cationic substitution element and the P element (R Y / P ), the atomic number ratio of the anionic substitution element and the S element (R N / S ) in the aforementioned range, it is more conducive to maintaining a good ionic conductivity while reducing the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in an aqueous environment.

[0018] In some embodiments, the LGPS-type crystal phase satisfies one or more of the following characteristics:

[0019] The atomic number ratio of the Sn element and the S element is greater than or equal to 11 / 120;

[0020] The atomic number ratio of the Sn element and 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;

[0021] The atomic number ratio of the Sn element and the P element is greater than or equal to 11 / 19;

[0022] The atomic number ratio of the Sn element and the P element is less than or equal to 17 / 9, optionally, greater than or equal to 14 / 16 and less than or equal to 16 / 10.

[0023] By controlling at least one of the atomic number ratio of the Sn element and the S element, the atomic number ratio of the Sn element and the P element in the aforementioned range, it is more conducive to maintaining a good ionic conductivity while reducing the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in an aqueous environment.

[0024] In some embodiments, the LGPS-type crystal phase includes an Sb element;

[0025] Optionally, the atomic number ratio of the Sb element and the S element is greater than 0 and less than or equal to 4 / 86, further optionally, greater than or equal to 2 / 120 and less than or equal to 3 / 91;

[0026] Optionally, the atomic number ratio of the Sb element and the P element is greater than 0 and less than or equal to 4 / 9, further optionally, greater than or equal to 2 / 14 and less than or equal to 3 / 11;

[0027] 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 more further optionally, greater than or equal to 16 / 120 and less than or equal to 19 / 91;

[0028] 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, more further optionally, greater than or equal to 16 / 14 and less than or equal to 19 / 11.

[0029] By doping the antimony (Sb) element in the LGPS type crystal phase, the Sb element can replace part of the P element, further reducing the content of P element; based on the hard-soft acid-base theory, compared with the bonding strength of 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 release amount of hydrogen sulfide gas of the sulfide solid electrolyte in the aqueous environment.

[0030] By controlling at least one of the atomic mole 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 in the foregoing range, it is beneficial to reduce the release amount of hydrogen sulfide gas of the sulfide solid electrolyte in the aqueous environment while maintaining better ionic conductivity.

[0031] In some embodiments, the LGPS type crystal phase includes at least one of O element and Cl element;

[0032] Optionally, the LGPS type crystal phase includes O element, further optionally, the atomic number ratio of O element and S element is greater than 0 and less than or equal to 29 / 86;

[0033] Optionally, the atomic number ratio of O element and S element is greater than or equal to 0 and less than or equal to 29 / 86, further optionally, greater than or equal to 15 / 105 and less than or equal to 20 / 91;

[0034] Optionally, the LGPS type crystal phase includes Cl element, further optionally, the atomic number ratio of Cl element and S element is greater than 0 and less than or equal to 5 / 86;

[0035] Optionally, the atomic number ratio of Cl element and S element is greater than or equal to 0 and less than or equal to 5 / 86, further optionally, greater than or equal to 3 / 117 and less than or equal to 4 / 91.

[0036] By doping the oxygen (O) element in the LGPS type crystal phase, the O element can replace part of the S element, which is beneficial to further reduce the release amount of hydrogen sulfide gas of the sulfide solid electrolyte in the aqueous environment.

[0037] By doping the LGPS-type crystal phase with chlorine (Cl) elements, the Cl elements can replace a portion of S elements, which is conducive to further reducing the release of hydrogen sulfide gas in the aqueous environment of the sulfide solid electrolyte.

[0038] By controlling at least one of the atomic number ratio of O elements to S elements and the atomic number ratio of Cl elements to S elements within the aforementioned range, it is conducive to reducing the release of hydrogen sulfide gas in the aqueous environment of the sulfide solid electrolyte while maintaining good ionic conductivity.

[0039] In some embodiments, the LGPS-type crystal phase includes or does not include Sb elements, and further includes or does not include O elements, and further includes or does not include Cl elements.

[0040] wherein the atomic number ratio of Li elements, Sn elements, P elements, Sb elements, S elements, O elements and Cl elements is (10+x-m):(1+x):(2-x-y):y:(12-z-m):z:m; wherein 0

[0041] In some embodiments, the LGPS-type crystal phase has a chemical formula of Li 10+x-m Sn 1+x P 2-x-y Sb y S 12-z-m O z Cl m .

[0042] In some embodiments, the LGPS-type crystal phase satisfies one or more of the following characteristics:

[0043] (z+m)>0, optionally, 0<(z+m)≤3.4, and further optionally, 1.8≤(z+m)≤3.4;

[0044] 0.1≤x≤0.7, optionally, 0.4≤x≤0.6;

[0045] 0.2≤y≤0.4, optionally, 0.2≤y≤0.3;

[0046] 1.5≤z≤2.9, optionally, 1.5≤z≤2.5;

[0047] 0.3≤m≤0.5, optionally, 0.3≤m≤0.4.

[0048] 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 ranges, the content of P element can be reduced by Sn element, the content of P element can be selectively reduced by Sb element (which can be selectively utilized or not utilized), O element can be selectively used to replace S element, and Cl element can be selectively used to replace S element. On the one hand, the content of either Sn element or Sb element in the material structure can be increased by cation substitution, and the content of P element can be reduced. Based on the hard-soft acid-base theory, the chemical bond between soft acid (Sn or Sb) and soft base (S) is stronger than the bond strength between hard acid (P) and soft base (S), and this stronger chemical bond is not easily broken by water molecules, which can reduce the release amount of hydrogen sulfide gas in the sulfide electrolyte in a water-containing environment. On the other hand, the content of S element in the material structure can be reduced by anion substitution by replacing S element with either O element or Cl element, which can reduce the release amount of hydrogen sulfide gas.

[0049] When both cation substitution and anion substitution are performed, (z+m)>0, which can more effectively reduce the release amount of hydrogen sulfide gas.

[0050] In addition, by controlling one or more of x, y, z and m within the aforementioned ranges, it is beneficial to reduce the release amount of hydrogen sulfide gas in the sulfide solid electrolyte in a water-containing environment while maintaining good ionic conductivity.

[0051] In some embodiments, the LGPS-type crystal phase satisfies one, any two or all of the following characteristics:

[0052] y=0;

[0053] z=0;

[0054] m=0.

[0055] When y=0, the release amount of hydrogen sulfide gas in the sulfide solid electrolyte in a water-containing environment can be reduced without introducing Sb element.

[0056] When z=0, the release amount of hydrogen sulfide gas in the sulfide solid electrolyte in a water-containing environment can be reduced without doping O element.

[0057] When m=0, the release amount of hydrogen sulfide gas in the sulfide solid electrolyte in a water-containing environment can be reduced without doping Cl element.

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

[0059] When y = 0, z = 0, m = 0, the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in a water-containing environment can be reduced by controlling the atomic number ratio of Sn elements.

[0060] In some embodiments, 0 < y ≤ 0.4, z = 0, m = 0.

[0061] When 0 < y ≤ 0.4, z = 0, m = 0, the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in a water-containing environment can be reduced while maintaining good ionic conductivity based on the aforementioned cation substitution method.

[0062] In some embodiments, y = 0, 0 < z ≤ 2.9, m = 0.

[0063] When y = 0, 0 < z ≤ 2.9, m = 0, the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in a water-containing environment can be reduced while maintaining good ionic conductivity based on O element doping.

[0064] In some embodiments, y = 0, z = 0, 0 < m ≤ 0.5.

[0065] When y = 0, z = 0, 0 < m ≤ 0.5, the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in a water-containing environment can be reduced while maintaining good ionic conductivity based on Cl element doping.

[0066] In some embodiments, the LGPS-type crystal phase includes one or more of the compounds represented by the following chemical formulas: 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 and Li 10.2 Sn 1.5 P 1.5 S 10.2 O 1.5 Cl 0.3 .

[0067] By disposing one or more LGPS-type sulfide electrolytes in the sulfide solid electrolyte, it is more advantageous to reduce the amount of hydrogen sulfide gas released and to have better ionic conductivity.

[0068] In some embodiments, the 2θ (°) diffraction angles in the X-ray diffraction pattern of the sulfide solid electrolyte have characteristic peaks consistent with the LGPS-type crystal phase.

[0069] In some embodiments, the X-ray diffraction pattern of the sulfide solid electrolyte satisfies at least one of the following characteristics:

[0070] The 2θ (°) diffraction angles in the X-ray diffraction pattern of the sulfide solid electrolyte have 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 is 0.2 or 0.1;

[0071] The X-ray diffraction pattern of the sulfide solid electrolyte is obtained by using Cu Kα rays;

[0072] The X-ray diffraction pattern of the sulfide solid electrolyte is obtained by powder X-ray diffraction testing.

[0073] The chemical composition in the sulfide solid electrolyte can be confirmed by X-ray diffraction (XRD) detection.

[0074] In a second aspect of the present application, a preparation method of a sulfide solid electrolyte is provided, which can be used to prepare the sulfide solid electrolyte of the first aspect of the present application.

[0075] In some embodiments, the preparation method of the sulfide solid electrolyte includes the following steps:

[0076] A precursor mixture including Li2S, P2S5, SnS2 and elemental sulfur is provided according to a stoichiometric ratio of raw materials required, the precursor mixture including or not including a cation source, the precursor mixture including or not including an anion source; wherein the cation source is a raw material providing a cation substitution element, the anion source is a raw material providing an anion substitution element; when the sulfide solid electrolyte includes a cation substitution element, the cation substitution element includes an Sb element; when the sulfide solid electrolyte includes an anion substitution element, the anion substitution element includes at least one of an O element and a Cl element; when the sulfide solid electrolyte contains an Sb element, the precursor mixture includes Sb2S3; when the sulfide solid electrolyte contains an O element, the precursor mixture includes P2O5; when the sulfide solid electrolyte contains a Cl element, the precursor mixture includes LiCl;

[0077] 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, an atomic number ratio of Sn element and S element is greater than 1 / 12, and an atomic number ratio of Sn element and P element is greater than 1 / 2.

[0078] In some embodiments, the preparation method of the sulfide solid electrolyte satisfies one or more of the following features:

[0079] The weight percentage of the elemental sulfur relative to the precursor mixture is 2.9wt% to 3.1wt%;

[0080] The inert atmosphere is an argon atmosphere.

[0081] In the step of sintering the precursor mixture in an inert atmosphere, the sintering temperature is 520°C to 620°C, which can be optionally 530°C to 620°C.

[0082] The prepared sulfide solid electrolyte is the sulfide solid electrolyte of the first aspect of the present application.

[0083] The sulfide solid electrolyte of the first aspect of the present application can be obtained by sintering a corresponding precursor mixture with excess elemental sulfur at a certain sintering temperature.

[0084] In the third aspect of the present application, a solid electrolyte film is provided, which includes at least one of the sulfide solid electrolyte of the first aspect of the present application and the sulfide solid electrolyte prepared by the preparation method of the second aspect of the present application.

[0085] The sulfide solid electrolyte has high stability in a water-containing 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 film has good quality stability, and the corresponding solid-state battery can fully exert the high ionic conductivity advantage of the sulfide solid electrolyte and have good cycle performance.

[0086] In a fourth aspect of the present application, an electrode tab is provided, which comprises an electrode active material layer comprising an electrode active substance, and at least one of the sulfide solid electrolyte according to the first aspect of the present application and the sulfide solid electrolyte prepared by the preparation method according to the second aspect of the present application.

[0087] In some embodiments, the electrode tab is a positive electrode tab, 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.

[0088] Alternatively, the electrode tab is a negative electrode tab, the electrode active material layer is referred to as a negative electrode active material layer, and the electrode active substance is referred to as a negative electrode active substance.

[0089] The electrode tab provided with the aforementioned sulfide solid electrolyte has high stability of the sulfide solid electrolyte in a water-containing environment (such as air), low hydrogen sulfide release, and good chemical stability of the material, so that the electrode tab has good quality stability, and the solid-state battery assembled using the electrode tab can fully exert the high ionic conductivity advantage of the sulfide solid electrolyte and have good cycle performance.

[0090] The electrode tab can be a positive electrode tab or a negative electrode tab.

[0091] In a fifth aspect of the present application, a solid-state battery is provided, which comprises at least one of the sulfide solid electrolyte according to the first aspect of the present application, the sulfide solid electrolyte prepared by the preparation method according to the second aspect of the present application, the solid electrolyte film according to the third aspect of the present application, and the electrode tab according to the fourth aspect of the present application.

[0092] In some embodiments, the solid-state battery is a sulfide all-solid-state battery.

[0093] The solid-state battery provided with the aforementioned sulfide solid electrolyte can have the sulfide solid electrolyte arranged in one or more of a positive electrode layer, a negative electrode layer, and a solid electrolyte layer.

[0094] In a sixth aspect of the present application, there is provided a power consuming device comprising at least one of the sulfide solid electrolyte of the first aspect of the present application, the sulfide solid electrolyte prepared by the preparation method of the second aspect of the present application, the solid electrolyte membrane of the third aspect of the present application, the electrode sheet of the fourth aspect of the present application, and the solid-state battery of the fifth aspect of the present application.

[0095] The details of one or more embodiments or examples of the present application are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the present application will be apparent from the description, drawings, and claims. BRIEF DESCRIPTION OF DRAWINGS

[0096] To better describe and illustrate the embodiments, examples or examples provided by the present application, one or more drawings can be referred to. Additional details or examples used to describe the drawings should not be considered as limiting the scope of any one of the disclosed applications, the presently described embodiments, examples or examples, and the best mode presently understood of these applications. It should be noted that the drawings are all drawn in a simplified form, only for the convenience, clarity of explanation of the present application. The various sizes of each component shown in the drawings are arbitrarily shown, which can be accurate or not drawn according to the actual proportion. For example, in order to make the drawing clearer, the size of the components is appropriately exaggerated in some places of the drawing. Unless otherwise specified, the components in the drawing are not drawn to scale. The drawings of the present application do not limit the size of each component. Moreover, the same reference numerals are used to represent the same components in all the drawings. In the drawings:

[0097] FIG. 1 is a schematic view of a structure of a solid-state battery cell according to an embodiment of the present application, the solid-state battery cell comprising a positive electrode layer, a solid electrolyte layer, and a negative electrode layer which are sequentially stacked.

[0098] FIG. 2 is a schematic view of a solid-state battery cell according to an embodiment of the present application.

[0099] FIG. 3 is an exploded view of the solid-state battery cell according to an embodiment of the present application shown in FIG. 2.

[0100] FIG. 4 is a schematic view of a battery module according to an embodiment of the present application.

[0101] FIG. 5 is a schematic view of a battery pack according to an embodiment of the present application.

[0102] FIG. 6 is an exploded view of the battery pack according to an embodiment of the present application shown in FIG. 5.

[0103] FIG. 7 is a schematic view of a power consuming device using a solid-state battery as a power source according to an embodiment of the present application.

[0104] FIG. 8 is an X-ray diffraction (XRD) pattern of the sulfide solid electrolyte prepared in Preparation Example 1 and Preparation Comparative Example 1 of the present application, in which the abscissa axis is 2θ (°) and the ordinate axis is intensity.

[0105] BRIEF DESCRIPTION OF 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: housing; 52: solid-state battery core; 53: cover plate; 6: power consuming device. DETAILED DESCRIPTION

[0106] Hereinafter, some embodiments of the sulfide solid electrolyte and the method for preparing the same, the solid electrolyte membrane, the electrode sheet, the solid-state battery, the power consuming device, etc. provided by the present application are described in detail with appropriate reference to the accompanying drawings. However, there can be cases where unnecessary detailed descriptions are omitted. For example, there can be cases where detailed descriptions of matters well known in the art, repetitive descriptions of substantially identical structures are omitted. This is to avoid the following description from becoming unnecessarily lengthy and to facilitate understanding by those skilled in the art. In addition, the accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present application, and are not intended to limit the subject matter recited in the claims.

[0107] The "ranges" disclosed in the present application can be defined in the form of a lower limit and an upper limit, a given range is defined by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundaries of a particular range. The range defined in this way can be inclusive or exclusive of the end values, either end value can be independently included or excluded, and can be arbitrarily combined, i.e., any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60-120 and 80-110 are listed for a particular parameter, it is understood that ranges of 60-110 and 80-120 are also contemplated. In addition, if minimum range values of 1 and 2 are listed, and if maximum range values of 3, 4, and 5 are also listed, the following ranges are all contemplated: 1-3, 1-4, 1-5, 2-3, 2-4, and 2-5. In the present application, unless otherwise stated, a numerical range "a-b" represents a shorthand manner of describing any integer combination of the range between a and b, where a and b are both real numbers. For example, the numerical range "0-5" means that all real numbers between "0-5" have been listed herein, and "0-5" is just a shorthand notation for these numerical combinations. In addition, when it is stated that a certain parameter is an integer ≥ 2, it is equivalent to listing the parameter as, for example, integer 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc. For example, when it is stated that a certain parameter is an integer selected from "2-10", it is equivalent to listing the integers 2, 3, 4, 5, 6, 7, 8, 9, and 10.

[0108] In the present application, unless otherwise specified, "about" means a reasonable range of variation in the number, and the fluctuation range can 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 approximation ±1°C as an example, the approximation values of 19°C, 19.5°C, etc. within the approximation range indicated by "about 20°C" should also be included in the range indicated by "about 20°C".

[0109] In the present application, unless otherwise specified, "a plurality of", "a plurality of", "a plurality of", "several", etc. refer to more than 2 or equal to 2 in number. For example, "one or more" means one or ≥(greater than or equal to) two. It can be understood that when referring to "any plurality" of items, it refers to any suitable combination of a plurality of items, i.e. in a manner that does not conflict and can implement the present application.

[0110] If not specifically stated, all embodiments and optional embodiments of the present application can be combined with each other to form new technical solutions.

[0111] In the present application, the phrase "embodiment" means that the specific features, structures or characteristics described in conjunction with the embodiment can be included in at least one embodiment or embodiment of the present application. The appearance of this phrase in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment to other embodiments. Those skilled in the art understand explicitly and implicitly that the embodiments described herein can be combined with other embodiments. The phrase "embodiment" is similarly understood herein.

[0112] Those skilled in the art can understand that in the method of each embodiment or embodiment, the writing order of each step does not mean a strict execution order and does not constitute any limitation on the implementation process. The detailed execution order of each step should be determined by its function and possible internal logic. If not specifically stated, all steps of the present application can be performed sequentially or randomly, and can be preferably performed sequentially. For example, method M includes steps (a) and (b), which means that the method can include sequentially performed steps (a) and (b), or sequentially performed steps (b) and (a). For example, method M also includes step (c), which means that step (c) can be added to method M in any order, for example, method M can include steps (a), (b) and (c), or steps (a), (c) and (b), or steps (c), (a) and (b), etc.

[0113] In the present application, the open technical features or technical solutions described with the words "containing", "including", "comprising" and the like, if no other description, do not exclude additional members from the listed members, which can be regarded as providing both the closed features or solutions composed of the listed members, and the open features or solutions including additional members in addition to the listed members. For example, A includes a1, a2 and a3, if no other description, it can also include other members, or it can not include additional members, which can be regarded as providing both the features or solutions of "A is composed of a1, a2 and a3" or "A is selected from a1, a2 and a3", and the features or solutions of "A includes not only a1, a2 and a3, but also other members".

[0114] In the present application, A (such as B) means that B is a non-limiting example of A, and A can be understood as not limited to B, if no other description.

[0115] In the present application, "optionally", "optional" and "optional" mean that it can or can not be, that is, it is selected from any one of the two parallel solutions of "yes" or "no". If there are multiple "options" in a technical solution, if no special description, and there is no contradictory relationship or mutual restriction, each "option" is independent. If no other description, "optionally includes", "optionally contains" and the like in the present application, taking "optionally includes" as an example, means "may include or not include".

[0116] In the present application, if no other description, the "and / or" corresponding features or solutions include any one of two or more related listed items, and also include any and all combinations of related listed items, wherein any and all combinations include any two related listed items, any more related listed items, or all related listed items. For example, "A and / or B" indicates a group consisting of A, B and "the combination of A and B". Wherein, "including A and / or B" can mean "including A, including B, and including A and B", and also can mean "including A, including B, or including A and B", which can be understood according to the sentence.

[0117] The "combination thereof", "any combination thereof", "any combination thereof" and the like used herein include all suitable combination modes of any two or more listed items.

[0118] In this paper, "suitable combination mode", "suitable mode", "any suitable mode" and the like, "suitable" is subject to the implementation of the technical solutions of the present application.

[0119] In the present application, the terms "preferably", "more preferably", "even more preferably", "advantageously" or the like are used to describe optional features, desirable features or advantageous features of a product, a method, a process, an apparatus or the like. In no way these terms restrict the scope of protection of the present application.

[0120] In the present application, the terms "further", "even further", "in particular", "for example", "such as", "for instance", "e.g." or the like are used for descriptive purposes only and do not delimit the scope of protection of the present application.

[0121] In the present application, the terms "first", "second", "third", "fourth", "fifth", "sixth" or the like are used to describe various embodiments and do not connote an importance or a quantity. In the present application, the terms "first", "second", "third", "fourth", "fifth", "sixth" or the like are used to describe various embodiments and do not connote an importance or a quantity. In the present application, the terms "first", "second", "third", "fourth", "fifth", "sixth" or the like are used to describe various embodiments and do not connote an importance or a quantity. In the present application, the terms "first", "second", "third", "fourth", "fifth", "sixth" or the like are used to describe various embodiments and do not connote an importance or a quantity. In the present application, the terms "first", "second", "third", "fourth", "fifth", "sixth" or the like are used to describe various embodiments and do not connote an importance or a quantity.

[0122] In the present application, unless specifically stated and limited otherwise, the first feature is "on" or "under" the second feature can be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. In the present application, unless specifically stated and limited otherwise, the first feature is "on" or "under" the second feature can mean the mutual position relationship of horizontal height, or can only mean the existence of the attachment relationship without limiting the mutual position relationship of horizontal height.

[0123] In the present application, the term "room temperature" generally refers to 4℃ to 35℃, and can refer to 20℃±5℃. In some embodiments or examples of the present application, room temperature refers to 20℃ to 30℃.

[0124] In the present application, the units related to the range of data, if only the right end point is followed by a unit, it means that the units of the left end point and the right end point are the same. For example, 3-5h or 3-5h means that the units of the left end point "3" and the right end point "5" are both h (hours), which have the same meaning as 3h-5h. In addition, similar descriptions of other parameters such as temperature, size, etc. are also understood in the same way.

[0125] The weight or mass of the relevant components mentioned in the embodiments or examples of the present application can refer to the content of each component, and can also represent the proportional relationship between the weight or mass of each component. Therefore, as long as the content of the relevant components in 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 micrograms (μg), milligrams (mg), grams (g), kilograms (kg), and other mass units known in the chemical field. Unless otherwise specified, the mass ratio is equal to the corresponding weight ratio. For example, the mass of substance A is m1, the weight is W1, the mass of substance B is m2, and the weight is W2. The mass ratio m1 / m2 is equal to the corresponding weight ratio W1 / W2 in value.

[0126] In the present application, unless otherwise specified, wt% represents the percentage of weight by weight, which is equal in value to the corresponding percentage of mass by mass. In the present application, for the percentage of weight, “0” has the same meaning as “0 wt%” and can be used interchangeably.

[0127] In the present application, unless otherwise specified, nm represents nanometer, μm represents micrometer, S / cm represents siemens per centimeter, V represents volt, kV represents kilovolt, mA represents milliamperes, Hz represents hertz, mPa·S represents millipascal·second, mg / cm 2 represents milligrams per square centimeter, g / cm 2 represents grams per square centimeter, g / cm 3 represents grams per cubic centimeter, and ℃ represents Celsius.

[0128] In the present 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 equivalent to “>”, and “less than” can be equivalent to “<”. In the present application, unless otherwise specified, “greater than or equal to” and “≥” can be considered to provide two schemes of “greater than” and “equal to”. In the present application, unless otherwise specified, “less than or equal to” and “≤” can be considered to provide two schemes of “less than” and “equal to”.

[0129] In the present application, the exemplary descriptions involving “in some embodiments (or examples)”, “in one embodiment (or example)” and the like can cover but are not limited to the following meanings: these schemes can be combined with other schemes in a suitable manner to form new technical schemes.

[0130] In the present application, unless otherwise specified, the "solid-state battery" provided in the present application refers to a battery in which the electrolyte in the battery comprises a solid electrolyte; generally, the solid-state battery comprises a positive electrode layer, a solid electrolyte layer, and a negative electrode layer. During the charging and discharging process of the battery, active ions are reversibly inserted and extracted between the positive electrode layer and the negative electrode layer. The solid electrolyte layer plays a role in 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 short circuiting between the positive electrode layer and the negative electrode layer, and therefore, the solid-state battery can not be provided with a separator film in the traditional lithium-ion battery. The introduction of a non-flammable solid electrolyte to replace the organic electrolyte in the traditional liquid lithium-ion battery greatly improves the safety of the battery. In addition to improving safety, the solid-state battery can also better adapt to high-energy-density positive and negative electrode materials, and reduce the weight of the system, which is conducive to improving the energy density.

[0131] In the present application, unless otherwise specified, the "solid electrolyte" refers to an electrolyte material or electrolyte substance that exists in a solid state during the storage and preparation of the solid-state battery and the components constituting the solid-state battery, and during the working process of the solid-state battery. It can be understood that the solid electrolyte exists in a solid state at room temperature, including but not limited to.

[0132] In the present application, unless otherwise specified, the electrode layer can be a positive electrode layer or a negative electrode layer, and the electrode layer comprises an electrode active material. The electrode active material can be a positive electrode active material or a negative electrode active material. The electrode active material can be a particle itself or can be contained in an electrode active particle. The electrode active particle can be a positive electrode active particle or a negative electrode active particle. The "electrode active material" in the electrode layer refers to a material that can reversibly insert and extract active ions. Unless otherwise specified, the "negative electrode active material" refers to a material that can reversibly insert and extract active ions used in the negative electrode layer; the "positive electrode active material" refers to a material that can reversibly extract and insert active ions used in the positive electrode layer. When the solid-state battery is charged, active ions are extracted from the positive electrode and inserted into the negative electrode through the solid electrolyte layer; and when the solid-state battery is discharged, active ions are extracted from the negative electrode and inserted into the positive electrode. The active ion is not particularly limited, and the active ion can be a lithium ion, which corresponds to a lithium ion solid-state battery.

[0133] In the present application, the "electrode active particle" refers to a particle containing an electrode active material.

[0134] In the present 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.

[0135] In the present application, unless otherwise specified, "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. According to the detailed circumstances, the electrode active material layer can refer to the positive electrode active material layer or the negative electrode active material layer. It can be understood that the positive electrode active material layer contains positive electrode active substance, and the negative electrode active material layer contains negative electrode active substance. In the present application, "electrode active material layer" can also be abbreviated as "active material layer".

[0136] In the present application, unless otherwise specified, the positive electrode layer at least includes a positive electrode active material layer.

[0137] In the present application, unless otherwise specified, the positive electrode active material layer at least includes positive electrode active particles, and usually also includes positive electrode electrolyte particles.

[0138] In the present application, unless otherwise specified, "positive electrode active particles" refer to particles containing positive electrode active substance, which have the ability to reversibly release and embed active ions.

[0139] In the present application, unless otherwise specified, "positive electrode electrolyte particles" and "positive electrode solid electrolyte", "positive electrode electrolyte material" have the same meaning and can be used interchangeably, which refer to solid electrolyte that can be used in positive electrode film or positive electrode layer. Positive electrode electrolyte particles can enhance the ion conduction ability of positive electrode film or positive electrode layer, reduce the interface impedance, and can promote the charge transfer efficiency of positive electrode active substance and the full release of its capacity.

[0140] In the present application, unless otherwise specified, the negative electrode layer at least includes a negative electrode active material layer.

[0141] In the present application, unless otherwise specified, the negative electrode active material layer at least includes negative electrode active particles, and can or can not include negative electrode electrolyte particles.

[0142] In the present application, unless otherwise specified, "negative electrode active particles" refer to particles containing negative electrode active substance, which have the ability to reversibly embed and release active ions.

[0143] In the present application, unless otherwise specified, "negative electrode electrolyte particles" have the same meaning as "negative electrode solid electrolyte" and "negative electrode electrolyte material", and can be used interchangeably, referring to a solid electrolyte that can be used in a negative electrode film or negative electrode layer. The negative electrode electrolyte particles can enhance the ion conduction capability of the negative electrode film or negative electrode layer, reduce the interface impedance, and promote the charge transfer efficiency of the negative electrode active material and the full release of its capacity.

[0144] In a solid-state battery, interface contact and interface stability are one of the pain points that limit the performance of the battery. Poor interface contact can affect the cycle performance of the battery. Due to the "solid-solid contact" characteristics in the solid-state battery, the contact between the particles in 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. This causes insufficient interface ion transmission in the electrode layer, which in turn leads to suboptimal performance of the solid-state battery. By doping solid electrolyte material into the electrode layer, the ion conduction capability of the electrode layer can be theoretically enhanced, the charge transfer efficiency of the electrode active material and the full release of its capacity can be promoted, and the impedance can be reduced. Among the many solid electrolyte materials, sulfide solid electrolyte has the highest ion conductivity (about 10 -3 ~10 -2 S / cm) and excellent mechanical properties, such as good flexibility, making it an excellent ion conductor and a good deformable material, and is the most practical and industrialized solid electrolyte material. However, the stability of sulfide solid electrolyte is poor, and it can react with moisture in the air to release toxic hydrogen sulfide gas, which can also reduce the ion conductivity. In addition, hydrogen sulfide gas is flammable and explosive, which severely restricts the practical application of sulfide solid electrolyte.

[0145] Therefore, according to various embodiments and various examples of the present application, the embodiments and examples of the present application at least provide a sulfide solid electrolyte and a preparation method thereof, a solid electrolyte film, an electrode sheet, a solid-state battery, and an electric device. The embodiments and examples of the present application can also provide a positive electrode film, a negative electrode film, and a secondary battery. The sulfide solid electrolyte significantly reduces the release of hydrogen sulfide from the sulfide electrolyte in a water-containing environment.

[0146] In a first aspect of the present application, a sulfide solid electrolyte is provided, which includes an LGPS-type crystal phase.

[0147] In some embodiments, a sulfide solid electrolyte is provided, which includes an LGPS-type crystal phase; wherein the atomic number ratio of Sn element to S element is greater than 1 / 12, and the atomic number ratio of Sn element to P element is greater than 1 / 2.

[0148] In some embodiments, the LGPS-type crystal phase includes or does not include a cation substitution element. In some of these embodiments, when the LGPS-type crystal phase includes a cation substitution element, the cation substitution element includes an Sb element.

[0149] In some embodiments, the LGPS-type crystal phase includes or does not include an anion substitution element. In some of these embodiments, 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.

[0150] In some embodiments, a sulfide solid electrolyte is provided, which includes a LGPS-type crystal phase;

[0151] The LGPS-type crystal phase includes a Li element, a Sn element, a P element, and a S element, wherein an atomic number ratio of the Sn element and the S element is greater than 1 / 12, and an atomic number ratio of the Sn element and the P element is greater than 1 / 2.

[0152] In some embodiments, the LGPS-type crystal phase includes or does not include a cation substitution element, and includes or does not include an anion substitution element;

[0153] When the LGPS-type crystal phase includes a cation substitution element, the cation substitution element includes an Sb element.

[0154] 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.

[0155] In the present application, unless otherwise specified, "sulfide electrolyte" and "sulfide solid electrolyte" have the same meaning and can be used interchangeably, and refer to a solid electrolyte in a sulfide form, and the sulfide electrolyte includes a sulfur (S) element in a sulfide form. The "sulfide electrolyte" referred to in the embodiments or examples of the present application can be included in any one of a solid electrolyte layer, a positive electrode layer, and a negative electrode layer, can be included in an electrolyte material of a solid electrolyte layer, can be included in a positive electrode electrolyte particle, and can be included in a negative electrode electrolyte particle.

[0156] In the present application, unless otherwise specified, "LGPS-type crystal phase" refers to a crystal phase having a tetragonal crystal structure (P42 / mnm) that is the same as or similar to that of a lithium-germanium-phosphorus-sulfur (LGPS) sulfide solid electrolyte, and the LGPS-type crystal phase corresponds to an LGPS-type sulfide solid electrolyte; and "LGPS-type sulfide solid electrolyte" refers to a sulfide solid electrolyte having a tetragonal crystal structure that is the same as or similar to that of a lithium-germanium-phosphorus-sulfur (LGPS) sulfide solid electrolyte. The LGPS-type sulfide solid electrolyte has a composition of Li nmc ) of a lithium-germanium-phosphorus-sulfur (LGPS) sulfide solid electrolyte, and the LGPS-type crystal phase corresponds to an LGPS-type sulfide solid electrolyte; and "LGPS-type sulfide solid electrolyte" refers to a sulfide solid electrolyte having a tetragonal crystal structure that is the same as or similar to that of a lithium-germanium-phosphorus-sulfur (LGPS) sulfide solid electrolyte. The LGPS-type sulfide solid electrolyte has a composition of Li 10 GeP2S 12For example, the tetragonal crystal structure is composed of four basic units: [(M / P)S4] tetrahedron (M = Ge), [PS4] tetrahedron, [LiS6] octahedron and [LiS4] tetrahedron. The [(M / P)S4] tetrahedron and the [LiS6] octahedron are alternately connected by common edges in the c-axis direction to form a one-dimensional long chain, and the long chains are connected to each other by common vertices of the [LiS6] octahedron and the [PS4] tetrahedron to form a network structure.

[0157] In the sulfide solid electrolyte provided in the present application, in the tetragonal crystal structure of the LGPS-type crystal phase, M is partially or completely replaced by Sn, and partial doping of Sb 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 conventional Li 10 GeP2S 12 The P content in the tetragonal crystal phase.

[0158] In the present application, unless otherwise specified, the "atomic number ratio" refers to the number ratio of the specified element or atom, which can be measured in moles, in which case it corresponds to the "atomic molar ratio".

[0159] In the present application, when referring to numerical values, fractions are allowed to be used, for example, "1 / 12" means one twelfth, and "1 / 2" means one half.

[0160] In the present application, unless otherwise specified, whether the sulfide solid electrolyte includes the LGPS-type crystal phase can be determined according to 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 by using Cu Kα rays with a powder sample. Typically, the 2θ(°) scanning range includes at least 10°-50° (the scanning range can include 10°-80°), and the 2θ(°) scanning speed can be 0.02° / second. In some embodiments, the XRD testing instrument and parameters are as follows: Bruker-D8 advance, using Cu target Kα1 rays, wavelength λ is 0.15406 nm, the X-ray tube is controlled at 40 kV and 40 mA, the 2θ(°) scanning range is 10°-80°, and the 2θ(°) scanning speed is 0.02° / second. Those skilled in the art can determine the XRD testing instrument and parameters according to the Li 10 GeP2S 12The comparison analysis of the XRD standard spectrum confirms whether the to-be-tested sulfide solid electrolyte includes the LGPS-type crystal phase. In some embodiments, the X-ray diffraction pattern of the sulfide solid electrolyte has peaks near 14.6°, 17.4°, 20.2°, 20.5°, 24.0°, 26.9°, 29.5°, 32.6°, 36.5°, 41.5°, and 47.3° in the 2θ (°) diffraction angle of the following group. Due to the differences in measurement instruments, measurement conditions, and other measurement factors, the position of a certain peak or some peaks in the actually obtained X-ray diffraction pattern may be slightly offset (for example, ± δ°), but it can be understood that for those skilled in the art, it can be identified from the whole that "whether the X-ray diffraction pattern including slightly different characteristic peaks constitutes the LGPS-type crystal phase in essence". Unless otherwise specified, "± δ°" only represents the error of the peak value in the diffraction angle position, and is irrelevant to the peak shape and peak width of the peak. In terms of numerical value, regarding the aforementioned peak position offset ± δ°, δ can be 0.4, 0.3, 0.2, 0.1, and the like, for example, in some embodiments, δ = 0.2.

[0161] In the present application, unless otherwise specified, the element types and the atomic number ratio of each element in the sulfide solid electrolyte can be determined according to the elemental analysis method such as inductively coupled plasma spectrometer (ICP method), so as to determine the chemical formula.

[0162] The sulfide solid electrolyte includes the LGPS-type crystal phase, by controlling the atomic number ratio of tin (Sn) element and sulfur (S) element to be greater than 1 / 12 (twelfth) and controlling the atomic number ratio of Sn element and P element to be greater than 1 / 2 (half), the content of phosphorus (P) element can be reduced. Based on the Hard Soft Acid Base-HSAB theory, compared with the bonding strength of hard acid (P) and soft base (S), soft acid (Sn) and soft base (S) can form a stronger chemical bond, which is not easily broken by water molecules, which can significantly reduce the release amount of hydrogen sulfide gas of the sulfide solid electrolyte in the aqueous environment (such as air).

[0163] In the sulfide solid electrolyte, the LGPS-type crystal phase can include or not include a substitution element.

[0164] In the present application, unless otherwise specified, "substitution element" refers to other elements other than Li, Sn, P, and S.

[0165] In some embodiments, the LGPS-type crystal phase includes an acceptable substitution element.

[0166] In the present application, unless otherwise specified, "an acceptable substituting element" refers to an element that, after being introduced, still maintains the LGPS-type crystal phase and still has a low hydrogen sulfide release amount in an aqueous environment (see the hydrogen sulfide release amount level in the following examples).

[0167] In some embodiments, the LGPS-type crystal phase includes a substituting element. Further, the substituting element can include one or more of a cation substituting element and an anion substituting element.

[0168] In the present application, unless otherwise specified, a "cation substituting element" is an element that can participate in providing a cation; in some embodiments, the cation substituting element can substitute for part of the P element in the LGPS-type crystal phase.

[0169] In some embodiments, the cation substituting element includes an Sb element. In some embodiments, the cation substituting element is an Sb element.

[0170] In the present application, unless otherwise specified, an "anion substituting element" is an element that can participate in providing an anion; in some embodiments, the anion substituting element can substitute for part of the S element in the LGPS-type crystal phase.

[0171] In some embodiments, the anion substituting element includes at least one of an O element and a Cl element. In some embodiments, the anion substituting element is at least one of an O element and a Cl element.

[0172] In some embodiments, the substituting element includes at least one of an Sb element, an O element, and a Cl element. In some of these embodiments, the substituting element is at least one of an Sb element, an O element, and a Cl element.

[0173] In the sulfide solid electrolyte, the LGPS-type crystal phase can or can not include a cation substituting element.

[0174] In the sulfide solid electrolyte, the LGPS-type crystal phase can or can not include an anion substituting element.

[0175] 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.

[0176] 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 .

[0177] 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 / P 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, 1 / 14, 1.5 / 13.5, 2 / 14, 2.5 / 12.5, 3 / 11, 4 / 11, 4 / 10, 4 / 9, etc.

[0178] 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.

[0179] 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 RN / S .

[0180] In some embodiments, R N / S may be denoted as a ratio of N3 and N2 (N3 / N2), where N3 is a suitable value greater than or equal to 0, and N2 is a suitable positive value 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 can 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. For R N / S , N3 and N2 can be in any combination. In some embodiments, R N / S may be selected from an interval of any two N3 / N2 values. Without limitation, R N / S may 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 selected from an interval of any two of the following values: 0, 3 / 117, 15 / 105, 18 / 102, 24 / 96, 29 / 91, 34 / 91, 34 / 86, etc.

[0181] In some embodiments, N3+N2=120.

[0182] In some embodiments, 0≤R N / S ≤34 / 86, optionally, 0 N / S ≤34 / 86, further optionally, 18 / 102≤R N / S ≤29 / 91.

[0183] By controlling at least one of the atomic number ratio of the cation substitution element and the P element (R Y / P ) and the atomic number ratio of the anion substitution element and the S element (R N / S ) within the aforementioned ranges, it is more conducive to maintaining a good ionic conductivity while reducing the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in an aqueous environment.

[0184] In some embodiments, in the LGPS-type crystal phase, the atomic number ratio of the Sn element and the S element (which can be denoted as R Sn / Sgreater than 1 / 12 (i.e., greater than 10 / 120), the atomic ratio of Sn element to P element (denoted as R Sn / P greater than 1 / 2 (i.e., greater than 10 / 20).

[0185] In some embodiments, R Sn / S may be denoted as a ratio (N1 / N2) of N1 and N2, where N1 is a suitable positive number 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 , N1 and N2 described above can be combined in any manner. In some embodiments, R Sn / S may be selected from an interval formed by any two N1 / N2 values.

[0186] Without limitation, the atomic ratio of Sn element to S element (R Sn / S ) can be any one of the following values, greater than or equal to any one of the following values, greater than 1 / 12 and less than or equal to any one of the following values, or selected from an interval formed by 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 0.1417), 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.

[0187] In some embodiments, R Sn / S > 1 / 12, and R Sn / S may be optionally greater than 11 / 120.

[0188] In some embodiments, R Sn / S ≤ 17 / 86, and R Sn / S may be optionally 14 / 120≤ R ≤ 16 / 91.

[0189] In the present application, the atomic ratio of Sn and P in the LGPS-type crystal phase can be denoted as R Sn / P .

[0190] In some embodiments, R Sn / P may be denoted as the ratio of N1 and N4 (N1 / N4), where N1 can refer to the aforementioned 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. For R Sn / P , the aforementioned N1 and N4 can be combined in any manner. In some embodiments, R Sn / P may be selected from an interval formed by any two of the N1 / N4 values. Without limitation, the atomic ratio of Sn and P (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 selected from an interval formed by 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.

[0191] In some embodiments, R Sn / P >1 / 2, and optionally, R Sn / P ≥11 / 19.

[0192] In some embodiments, R Sn / P ≤17 / 9, and optionally, 14 / 16≤R Sn / P ≤16 / 10.

[0193] In some embodiments, the LGPS-type crystal phase satisfies one or more of the following characteristics (any of the numerical parameters in the following characteristics can also be selected from any suitable numerical value or range in the context):

[0194] The atomic ratio of Sn and S (R Sn / S ) is greater than 1 / 12, and optionally, R Sn / S is greater than or equal to 11 / 120;

[0195] The atomic ratio of Sn and S (R Sn / S ) is less than or equal to 17 / 86, and optionally, R Sn / Sgreater than or equal to 14 / 120 and less than or equal to 16 / 91;

[0196] an atomic ratio (R Sn / P ) of the Sn element and the P element is greater than 1 / 2, and optionally, R Sn / P greater than or equal to 11 / 19;

[0197] an atomic ratio (R Sn / P ) of the Sn element and the P element is less than or equal to 17 / 9, and optionally, R Sn / P greater than or equal to 14 / 16 and less than or equal to 16 / 10.

[0198] By controlling at least one of the atomic ratio (R Sn / S ) of the Sn element and the S element and the atomic ratio (R Sn / P ) of the Sn element and the P element within the aforementioned ranges, it is more conducive to maintaining a good ionic conductivity while reducing the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in a water-containing environment.

[0199] In the sulfide solid electrolyte, the LGPS-type crystal phase can or can not include the Sb element. In some embodiments, the LGPS-type crystal phase includes the Sb element.

[0200] By doping the antimony (Sb) element in the LGPS-type crystal phase, the Sb element can replace part of the P element, further reducing the content of the P element; based on the hard-soft acid-base theory, compared with the bonding strength of the hard acid (P) and the soft base (S), the soft acid (Sb) and the soft base (S) also have a stronger chemical bond and are not easily destroyed by water molecules, which can further reduce the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in a water-containing environment.

[0201] In this application, the atomic ratio of the Sb element and the S element in the LGPS-type crystal phase can be denoted as R Sb / S .

[0202] In some embodiments, in numerical value, R Sb / S can be denoted as the ratio (N5 / N2) of N5 and N2, wherein N5 is a suitable numerical value greater than or equal to 0, and N2 can be referred to the definition above. In some embodiments, 0≤N5≤4, and N5 can also be any one of the following numerical values: 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, etc. For R Sb / S , the aforementioned N5 and N2 can be combined in any manner. In some embodiments, R Sb / S may be selected from an interval formed by any two N5 / N2 numerical values. Without limitation, the atomic ratio (R Sb / SIn some embodiments, R can be equal to 0. Sb / S In some embodiments, R can be equal to 0.

[0203] In some embodiments, R can be equal to 0. Sb / P .

[0204] In some embodiments, R can be equal to 0. Sb / P In some embodiments, R can be equal to 0. Sb / P In some embodiments, R can be equal to 0. Sb / P In some embodiments, R can be equal to 0. Sb / P In some embodiments, R can be equal to 0.

[0205] In some embodiments, R can be equal to 0. (Sn+Sb) / S In some embodiments, R can be equal to 0. (Sn+Sb) / S In some embodiments, R can be equal to 0. Sn / S In some embodiments, R can be equal to 0. Sb / S In some embodiments, R can be equal to 0.

[0206] In some embodiments, R can be equal to 0. (Sn+Sb) / S In some embodiments, R can be equal to 0. (Sn+Sb) / S In some embodiments, R can be equal to 0. (Sn+Sb) / Smay 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 an interval consisting of 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. (Sn+Sb) / S )may 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 an interval consisting of 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.

[0207] In the present application, the atomic ratio of the sum of Sn element and Sb element to P element in the LGPS-type crystal phase can be denoted as R (Sn+Sb) / P In numerical terms, R (Sn+Sb) / P = R Sn / P + R Sb / P .

[0208] In some embodiments, in numerical terms, R (Sn+Sb) / P may be denoted as the ratio of N6 and N4 (N6 / N4), wherein N6 can refer to the foregoing definition, and N4 can refer to the foregoing definition. For R (Sn+Sb) / P , N6 and N4 can be in any combination. In some embodiments, R (Sn+Sb) / P may be selected from an interval consisting of any two of the following N6 / N4 values. Non-limitingly, the atomic ratio of the sum of Sn element and Sb element to P element (R (Sn+Sb) / P )may be any one of the following values, greater than or equal to any one of the following values, greater than 10 / 20 and less than or equal to any one of the following values, or selected from 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.

[0209] In some embodiments, N6+N4=30.

[0210] In some embodiments, 0≤R Sb / S ≤4 / 86, optionally, 0 Sb / S ≤4 / 86, further optionally, 2 / 120≤R Sb / S ≤3 / 91.

[0211] In some embodiments, 0≤R Sb / P ≤4 / 9, optionally, 0 Sb / P ≤4 / 9, further optionally, 2 / 14≤R Sb / P ≤3 / 11.

[0212] 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.

[0213] 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.

[0214] In some embodiments, the LGPS-type crystal phase satisfies one or more of the following characteristics (any numerical parameter in the following characteristics can also be selected from any suitable numerical value or range in the context):

[0215] The atomic number ratio (R Sb / S ) of the Sb element and the S element is greater than or equal to 0 and less than or equal to 4 / 86, optionally, R Sb / S is greater than 0 and less than or equal to 4 / 86, further optionally, R Sb / S is greater than or equal to 2 / 120 and less than or equal to 3 / 91;

[0216] The atomic number ratio (R Sb / P ) of the Sb element and the P element is greater than or equal to 0 and less than or equal to 4 / 9, optionally, greater than 0 and less than or equal to 4 / 9, further optionally, greater than or equal to 2 / 14 and less than or equal to 3 / 11;

[0217] The atomic number ratio (R (Sn+Sb) / S ) of the sum of the Sn element and the Sb element relative to the S element is greater than 1 / 12 and less than or equal to 21 / 86, optionally, R (Sn+Sb) / S is greater than or equal to 11 / 120 and less than or equal to 21 / 86, further optionally, R (Sn+Sb) / S is greater than or equal to 16 / 120 and less than or equal to 19 / 91;

[0218] Optionally, the atomic number ratio (R (Sn+Sb) / P ) of the sum of the Sn element and the Sb element relative to the P element is greater than 1 / 2 and less than or equal to 21 / 9, optionally, R (Sn+Sb) / P is greater than or equal to 11 / 19 and less than or equal to 21 / 9, further optionally, R (Sn+Sb) / P is greater than or equal to 16 / 14 and less than or equal to 19 / 11.

[0219] By controlling at least one of the atomic molar of the Sb element and the S element, the atomic number ratio of the sum of the Sn element and the Sb element relative to the atomic number of the S element, and the atomic number ratio of the sum of the Sn element and the Sb element relative to the atomic number of the P element within the aforementioned ranges, it is beneficial to reduce the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in the aqueous environment while maintaining a good ionic conductivity.

[0220] In the sulfide solid electrolyte, the LGPS-type crystal phase can include or not include O element.

[0221] In the sulfide solid electrolyte, the LGPS-type crystal phase can include or not include Cl element.

[0222] In some embodiments, the LGPS-type crystal phase includes at least one of O element and Cl element.

[0223] In some embodiments, the LGPS-type crystal phase includes O element.

[0224] By doping oxygen (O) element in the LGPS-type crystal phase, the O element can replace a part of S element, which is beneficial to further reduce the amount of hydrogen sulfide gas released by the sulfide solid electrolyte in the aqueous environment.

[0225] In this application, the atomic number ratio of O element and S element in the LGPS-type crystal phase can be denoted as R O / S .

[0226] In some embodiments, R O / S can be denoted as the ratio of N7 and 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, 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. N7 and N2 can be any combination for R O / S . In some embodiments, R O / S may be selected from an interval consisting of any two N7 / N2 values. Without limitation, 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 selected from an interval consisting of any two of the following values: 15 / 105, 20 / 96, 20 / 91, 25 / 91, 29 / 86, etc.

[0227] In some embodiments, the LGPS-type crystal phase includes O element, and optionally, 0O / S ≤ 29 / 86.

[0228] In some embodiments, 0≤R O / S ≤ 29 / 86, optionally, 15 / 105≤R O / S ≤ 20 / 91.

[0229] In some embodiments, the LGPS-type crystal phase comprises Cl element.

[0230] By doping Cl element in the LGPS-type crystal phase, the Cl element can replace a part of S element, which is beneficial to further reduce the release amount of hydrogen sulfide gas of the sulfide solid electrolyte in the aqueous environment.

[0231] In the present application, the atomic number ratio of Cl element to S element in the LGPS-type crystal phase can be denoted as R Cl / S .

[0232] In some embodiments, R Cl / S can be denoted as the ratio of N8 to N2 (N8 / N2), wherein 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. For R Cl / S , N8 and N2 can be combined in any manner. In some embodiments, R Cl / S may be selected from an interval formed by any two N8 / N2 values. Without limitation, the atomic number ratio of Cl element to 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 selected from an interval formed by any two of the following values: 3 / 117, 4 / 96, 4 / 91, 5 / 86, etc.

[0233] In some embodiments, the LGPS-type crystal phase comprises Cl element, and optionally, 0 Cl / S ≤ 5 / 86.

[0234] In some embodiments, 0≤R Cl / S ≤ 5 / 86, optionally, 3 / 117≤R Cl / S ≤ 4 / 91.

[0235] In some embodiments, the LGPS-type crystal phase comprises at least one of Cl element and O element; further, the LGPS-type crystal can satisfy one or more of the following characteristics (any numerical parameter in the following characteristics can also be selected from any suitable value or range in the context):

[0236] The LGPS-type crystal phase includes O elements, and further optionally, 0 < R O / S ≤ 29 / 86;

[0237] The atomic number ratio (R O / S ) of the O elements and the S elements is greater than or equal to 0 and less than or equal to 29 / 86, and further optionally, R O / S is greater than or equal to 15 / 105 and less than or equal to 20 / 91;

[0238] The LGPS-type crystal phase includes Cl elements, and further optionally, 0 < R Cl / S ≤ 5 / 86;

[0239] The atomic number ratio (R Cl / S ) of the Cl elements and the S elements is greater than or equal to 0 and less than or equal to 5 / 86, and further optionally, R Cl / S is greater than or equal to 3 / 117 and less than or equal to 4 / 91.

[0240] By controlling at least one of the atomic number ratio of the O elements and the S elements, the atomic number ratio of the Cl elements and the S elements within the aforementioned ranges, it is possible to reduce the amount of hydrogen sulfide gas released from the sulfide solid electrolyte in an aqueous environment while maintaining a good ionic conductivity.

[0241] In some embodiments, the LGPS-type crystal phase includes or does not include Sb elements, and further includes or does not include O elements, and further includes or does not include Cl elements; wherein the atomic number ratio of the Li elements, the Sn elements, the P elements, the Sb elements, the S elements, the O elements, and the Cl elements is (10+x-m):(1+x):(2-x-y):y:(12-z-m):z:m; wherein 0 < x ≤ 0.7, 0 ≤ y ≤ 0.4, 0 ≤ z ≤ 2.9, and 0 ≤ m ≤ 0.5;

[0242] At this time, R Sn / S＝ (1+x) / (12-z-m), R Sn / P =(1+x) / (2-x-y), R Sb / S =y / (12-z-m), R (Sn+Sb) / S =(1+x+y) / (12-z-m), R (Sn+Sb) / P =(1+x+y) / (2-x-y), R O / S =z / (12-z-m), R Cl / S =m / (12-z-m).

[0243] 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-mO z Cl m .

[0244] Without limitation, 0 < (z + m) < 3.4. In some embodiments, (z + m) > 0. In this case, the LGPS-type crystal phase includes at least one of O and Cl elements. Without limitation, 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 interval between 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, such as 0 < (z + m) < 3.4, 1.8 < (z + m) < 3.4, etc.

[0245] Without limitation, 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 interval between 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 non-limiting examples, x can be selected from any suitable range, such as 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.

[0246] Without limitation, 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 interval between any two of the following values: 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, etc. As non-limiting examples, y can be selected from any suitable range, such as 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.

[0247] 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 selected from the interval between 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 non-limiting examples, 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.

[0248] Without limitation, 0 < m < 0.5. m 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 interval between 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 can 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.

[0249] In some embodiments, the LGPS-type crystalline phase satisfies one or more of the following characteristics (any of the numerical parameters in the following characteristics can also be selected from any suitable numerical value or range in the context):

[0250] (z + m) > 0, optionally, 0 < (z + m) < 3.4, further optionally, 1.8 < (z + m) < 3.4;

[0251] 0.1 < x < 0.7, optionally, 0.4 < x < 0.6;

[0252] 0.2 < y < 0.4, optionally, 0.2 < y < 0.3;

[0253] 1.5 < z < 2.9, optionally, 1.5 < z < 2.5;

[0254] 0.3 < m < 0.5, optionally, 0.3 < m < 0.4.

[0255] 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.

[0256] When cation substitution and anion substitution are performed simultaneously, (z+m)>0, which can more effectively reduce the amount of hydrogen sulfide gas released.

[0257] 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.

[0258] In some embodiments, the LGPS-type crystalline phase satisfies one, any two, or three of the following characteristics:

[0259] y=0;

[0260] z = 0;

[0261] m=0.

[0262] In some embodiments, y=0, optionally, y=z=0, and further optionally y=m=0.

[0263] In some embodiments, z=0, optionally, z=m=0.

[0264] In some embodiments, m=0.

[0265] 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.

[0266] 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.

[0267] 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.

[0268] In some embodiments, y=0, z=0, and m=0.

[0269] 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.

[0270] In some embodiments, 0 <y≤0.4,z=0,m=0。

[0271] When 0 < y < 0.4, z = 0, m = 0, the cation substitution can be based on the aforementioned substitution modes to reduce the amount of hydrogen sulfide gas released from the sulfide solid electrolyte in an aqueous environment while maintaining good ionic conductivity.

[0272] In some embodiments, y = 0, 0 < z < 2.9, m = 0.

[0273] When y = 0, 0 < z < 2.9, m = 0, the O element doping can be based on the aforementioned substitution modes to reduce the amount of hydrogen sulfide gas released from the sulfide solid electrolyte in an aqueous environment while maintaining good ionic conductivity.

[0274] In some embodiments, y = 0, z = 0, 0 < m < 0.5.

[0275] When y = 0, z = 0, 0 < m < 0.5, the Cl element doping can be based on the aforementioned substitution modes to reduce the amount of hydrogen sulfide gas released from the sulfide solid electrolyte in an aqueous environment while maintaining good ionic conductivity.

[0276] In some embodiments, the LGPS-type crystal phase includes one or more of the following compounds represented by the following chemical formulas: 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 , and Li 10.2 Sn 1.5 P 1.5 S 10.2 O 1.5 Cl 0.3 .

[0277] By disposing one or more LGPS-type sulfide electrolytes in the sulfide solid electrolyte, it is more advantageous to reduce the amount of hydrogen sulfide gas released and to have better ionic conductivity.

[0278] In some embodiments, the 2-theta (°) diffraction angles in the X-ray diffraction pattern of the sulfide solid electrolyte have characteristic peaks consistent with the LGPS-type crystal phase. For the definition and identification method of the "LGPS-type crystal phase", please refer to the foregoing.

[0279] In some embodiments, the 2-theta (°) diffraction angles in the X-ray diffraction pattern of the sulfide solid electrolyte have 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 can be referred to the foregoing; optionally, δ is 0.2 or 0.1.

[0280] In some embodiments, the X-ray diffraction pattern of the sulfide solid electrolyte is obtained by using Cu Kα rays, and in some of the embodiments, the X-ray diffraction pattern of the sulfide solid electrolyte is obtained by using Cu Kα1 rays.

[0281] In some embodiments, the X-ray diffraction pattern of the sulfide solid electrolyte is obtained by powder X-ray diffraction test.

[0282] In some embodiments, the X-ray diffraction pattern of the sulfide solid electrolyte satisfies at least one of the following characteristics:

[0283] The 2-theta (°) diffraction angles in the X-ray diffraction pattern of the sulfide solid electrolyte have 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 can be referred to the foregoing; optionally, δ is 0.2 or 0.1 (in some embodiments, δ is 0.2; in other embodiments, δ is 0.1);

[0284] The X-ray diffraction pattern of the sulfide solid electrolyte is obtained by using Cu Kα rays;

[0285] The X-ray diffraction pattern of the sulfide solid electrolyte is obtained by powder X-ray diffraction test.

[0286] The chemical composition in the sulfide solid electrolyte can be confirmed by X-ray diffraction (XRD) detection.

[0287] 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.

[0288] In some embodiments, the method for preparing a sulfide solid electrolyte comprises the following steps:

[0289] S100: providing a precursor mixture comprising Li2S, P2S5, SnS2 and elemental sulfur according to the stoichiometric ratio of raw materials required, the precursor mixture comprising or not comprising a cation source, the precursor mixture comprising or not comprising an anion source; wherein the cation source is a raw material providing a cation substitution element, and the anion source is a raw material providing an anion substitution element;

[0290] Optionally, when the sulfide solid electrolyte comprises a cation substitution element, the cation substitution element comprises an Sb element;

[0291] Optionally, when the sulfide solid electrolyte comprises an anion substitution element, the anion substitution element comprises at least one of an O element and a Cl element;

[0292] Further optionally, when the sulfide solid electrolyte contains an Sb element, the precursor mixture comprises Sb2S3; when the sulfide solid electrolyte contains an O element, the precursor mixture comprises P2O5; and when the sulfide solid electrolyte contains a Cl element, the precursor mixture comprises LiCl;

[0293] S200: sintering the precursor mixture in an inert atmosphere to prepare a sulfide solid electrolyte comprising a LGPS-type crystal phase; in the LGPS-type crystal phase, the atomic number ratio of Sn element to S element is greater than 1 / 12, and the atomic number ratio of Sn element to P element is greater than 1 / 2;

[0294] Optionally, in the step of sintering the precursor mixture in an inert atmosphere, the sintering temperature (denoted as T1) can be 520-620°C.

[0295] In the present application, unless otherwise specified, “providing according to the stoichiometric ratio of raw materials required” in step S100 means providing in the stoichiometric ratio of raw materials required to obtain the target chemical formula. In the case where the target chemical formula is determined, a person skilled in the art can select appropriate precursor raw materials and appropriate stoichiometric ratios of raw materials. During the sintering process of step S200, sulfur evaporation loss usually occurs. Therefore, in step S100, elemental sulfur is usually added in excess.

[0296] Non-limitingly, the weight percentage of elemental sulfur relative to the precursor mixture can be 2.9-3.1 wt%, such as 2.9 wt%, 3 wt%, 3.1 wt%, etc.

[0297] Non-limitingly, in step S200, the sintering temperature T1 can be 520-620℃, optionally 530-620℃, and can also be any two of the following temperatures or a range selected from any two of the following temperatures: 520℃, 530℃, 540℃, 550℃, 560℃, 570℃, 580℃, 590℃, 600℃, 610℃, 620℃, etc.

[0298] Non-limitingly, in step S200, the inert atmosphere can be an argon atmosphere.

[0299] In some embodiments, the method for preparing the sulfide solid electrolyte satisfies one or more of the following characteristics (any numerical parameter in the following characteristics can also be selected from any suitable numerical value or range in the context):

[0300] The weight percentage of sulfur element relative to the precursor mixture is 2.9-3.1wt%;

[0301] The inert atmosphere is an argon atmosphere;

[0302] The sintering temperature T1 is 520-620℃, optionally 530-620℃;

[0303] The prepared sulfide solid electrolyte is the sulfide solid electrolyte described in the first aspect of the present application.

[0304] The sulfide solid electrolyte described in the first aspect of the present application can be obtained by sintering a corresponding precursor mixture containing excess sulfur element at a certain sintering temperature.

[0305] In the third aspect of the present application, a solid electrolyte film is provided, which comprises 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 method described in the second aspect of the present application.

[0306] Non-limitingly, the solid electrolyte film can be an independent solid electrolyte film piece, which is then used to assemble a solid-state battery; the solid electrolyte film can also be a solid electrolyte film layer present in a composite structure.

[0307] The solid electrolyte film can be prepared by conventional methods in the field of solid-state batteries, such as pressing the solid electrolyte material into a film.

[0308] In some embodiments, the solid electrolyte film is a full solid-state electrolyte film.

[0309] In the present application, unless otherwise specified, the "full solid-state electrolyte film" refers to a solid electrolyte film whose constituent materials are all in solid state.

[0310] In another aspect of the present application, a solid electrolyte film is provided, which comprises 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.

[0311] In another aspect of the present application, a positive electrode film is provided, which comprises a positive electrode active material layer, the positive electrode active material layer 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.

[0312] Without limitation, the positive electrode film can be a separate positive electrode film or a positive electrode tab, which is further used for assembling 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 material 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 part of a positive electrode layer of a solid-state battery.

[0313] In some embodiments, the negative electrode film is a full solid-state positive electrode film.

[0314] In the present application, unless otherwise specified, the "full solid-state positive electrode film" refers to a positive electrode film whose constituent materials are all in solid state.

[0315] In another aspect of the present application, a positive electrode film is provided, which comprises a positive electrode current collector and a positive electrode active material layer located on at least one side of the positive electrode current collector, the positive electrode active material layer 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.

[0316] In another aspect of the present application, a negative electrode film is provided, which comprises a negative electrode active material layer, the negative electrode active material layer 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.

[0317] Without limitation, the negative electrode film can be a separate negative electrode film or a negative electrode tab, which is further used for assembling 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 material 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 part of a negative electrode layer of a solid-state battery.

[0318] In some embodiments, the negative electrode film is a full solid-state negative electrode film.

[0319] In the present application, unless otherwise specified, the "full solid-state negative electrode film" refers to a negative electrode film whose constituent materials are all in solid state.

[0320] In another aspect of the present application, a negative electrode sheet is provided, which comprises a negative electrode current collector and a negative electrode active material layer located on at least one side of the negative electrode current collector, the negative electrode active material layer 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.

[0321] For the solid electrolyte film, the positive electrode film or the negative electrode film provided with the aforementioned sulfide solid electrolyte, the sulfide solid electrolyte has high stability in a water-containing environment (such as air) and low hydrogen sulfide release amount, and the material has good chemical stability, so that the sulfide solid electrolyte in the solid electrolyte film, the positive electrode film or the negative electrode film has good quality stability, which is conducive to making the corresponding secondary battery or solid-state battery fully exert the high ionic conductivity advantage of the sulfide solid electrolyte, and the cycle performance can be good.

[0322] In the fourth aspect of the present application, an electrode sheet is provided, which comprises an electrode active material layer comprising an electrode active substance, and the electrode active material layer further comprises 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.

[0323] In some embodiments, 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.

[0324] Alternatively, the electrode sheet is a negative electrode sheet, the electrode active material layer is referred to as a negative electrode active material layer, and the electrode active substance is referred to as a negative electrode active substance.

[0325] In the present application, unless otherwise specified, the electrode sheet comprises an electrode active material layer. As described previously, the electrode active material layer comprises an electrode active substance. In the electrode sheet, the electrode active substance can itself constitute a particulate substance or can be contained in an electrode active particle. Unless otherwise specified, the electrode active material layer in the electrode sheet provided in this aspect further comprises a sulfide solid electrolyte, and further, the electrode active material layer comprises 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.

[0326] In some embodiments, the electrode active material layer comprises electrode active particles, and the electrode active material layer further comprises 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. The electrode tab can be a positive electrode tab, and the electrode active particles are positive electrode active particles. In this case, a positive electrode tab is provided, which comprises a positive electrode active material layer, and the positive electrode active material layer comprises positive electrode active particles and the aforementioned sulfide solid electrolyte. The electrode tab can also be a negative electrode tab, and the electrode active particles are negative electrode active particles. In this case, a negative electrode tab is provided, which comprises a negative electrode active material layer, and the negative electrode active material layer comprises negative electrode active particles and the aforementioned sulfide solid electrolyte.

[0327] For the electrode tab provided with the aforementioned sulfide solid electrolyte, the sulfide solid electrolyte has high stability in a water-containing environment (such as air) and low hydrogen sulfide release amount, and the material has good chemical stability, so that the electrode tab has good quality stability. The secondary battery or solid-state battery assembled using the electrode tab can fully exert the high ionic conductivity advantage of the sulfide solid electrolyte and have good cycle performance.

[0328] The electrode tab can be a positive electrode tab or a negative electrode tab.

[0329] In another aspect of the present application, a secondary battery is provided, which comprises 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 film described in the third aspect of the present application, the aforementioned positive electrode film, the aforementioned negative electrode film, and the electrode tab described in the fourth aspect of the present application.

[0330] In the present application, unless otherwise specified, the "secondary battery" provided in the foregoing of the present application comprises a positive electrode tab, a negative electrode tab, and a solid electrolyte layer between the positive electrode tab and the negative electrode tab.

[0331] In the present application, unless otherwise specified, the "positive electrode tab" comprises a positive electrode active material layer. In some embodiments, the positive electrode tab in the secondary battery is the aforementioned positive electrode film.

[0332] In the present application, unless otherwise specified, the "negative electrode tab" comprises a negative electrode active material layer. In some embodiments, the negative electrode tab in the secondary battery is the aforementioned negative electrode film.

[0333] In the present application, unless otherwise specified, the "solid electrolyte layer" comprises a solid electrolyte. In some embodiments, the solid electrolyte layer is a solid electrolyte film layer composed of the solid electrolyte film described in the third aspect of the present application.

[0334] During charging of the secondary battery, active ions are extracted from the positive electrode, pass through the solid electrolyte layer and are inserted into the negative electrode; and during discharging of the secondary battery, active ions are extracted from the negative electrode and inserted into the positive electrode. The active ions are not particularly limited, and non-limitingly, the active ions can be lithium ions, in which case the lithium ion secondary battery corresponds.

[0335] In a fifth aspect of the present application, a solid-state battery is provided, which comprises 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 film described in the third aspect of the present application, the positive electrode film described above, the negative electrode film described above, and the electrode tab described in the fourth aspect of the present application.

[0336] In some embodiments, the solid-state battery comprises 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 film described in the third aspect of the present application, and the electrode tab described in the fourth aspect of the present application.

[0337] In some embodiments, the positive electrode layer in the solid-state battery comprises the positive electrode film described above, and can further be the positive electrode film described above.

[0338] In some embodiments, the negative electrode layer in the solid-state battery comprises the negative electrode film described above, and can further be the negative electrode film described above.

[0339] In some embodiments, the solid electrolyte layer in the solid-state battery comprises the solid electrolyte film described in the third aspect of the present application, and can further be the solid electrolyte film described in the third aspect of the present application.

[0340] In some embodiments, the solid-state battery is a sulfide all-solid-state battery.

[0341] The "solid-state battery" provided in the fifth aspect of the present application comprises 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, and thus it is a sulfide solid-state battery.

[0342] In the present application, unless otherwise specified, "sulfide solid-state battery" refers to a solid-state battery in which the electrolyte involved in the battery comprises a sulfide solid electrolyte. The sulfide solid electrolyte can be located in at least one of the positive electrode layer, the negative electrode layer, and the solid electrolyte layer of the sulfide solid-state battery. The sulfide solid-state battery can further be an all-solid-state battery.

[0343] In the present application, unless otherwise specified, the "all-solid-state battery" refers to a solid-state battery in which the electrolyte in the battery is a solid electrolyte. In this case, the positive electrode layer, the negative electrode layer, and the electrolyte part all use solid materials, and no liquid electrolyte is provided in the battery, so it can be referred to as an "all-solid-state battery".

[0344] In the present application, unless otherwise specified, the "solid-state battery" in any embodiment or example can be, but is not limited to, a sulfide all-solid-state battery. Unless otherwise specified, the "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. Among them, the sulfide solid electrolyte can be located in at least one position of the positive electrode layer, the negative electrode layer, and the solid electrolyte layer of the sulfide all-solid-state battery.

[0345] The types of solid electrolytes present in different film layers of the secondary battery or the 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.

[0346] In the secondary battery or the solid-state battery provided in 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.

[0347] For the secondary battery or the solid-state battery provided with the aforementioned sulfide solid electrolyte, the sulfide solid electrolyte can be provided in one or more of the positive electrode layer, the negative electrode layer, and the solid electrolyte layer.

[0348] 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 a solid electrolyte material known in the art that can be used in a solid-state battery, for example, can each independently include one or more of the following materials: one or more of sulfide-based solid electrolytes, halide-based solid electrolytes, oxide-based solid electrolytes, polymer-based solid electrolytes, etc.

[0349] In the sixth aspect of the present application, 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 film described in the third aspect of the present application, the aforementioned positive electrode film, the aforementioned negative electrode film, the electrode tab described in the fourth aspect of the present application, the aforementioned secondary battery, and the solid-state battery described in the fifth aspect of the present application is provided.

[0350] In some embodiments, the power consuming device comprises 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 film described in the third aspect of the present application, the electrode sheet described in the fourth aspect of the present application, and the solid-state battery described in the fifth aspect of the present application.

[0351] The following is some description of the solid electrolyte layer.

[0352] The solid electrolyte layer functions to conduct ions between the positive electrode layer and the negative electrode layer, and also functions to isolate the positive electrode layer from the negative electrode layer to prevent short circuiting between the positive electrode and the negative electrode.

[0353] It can be understood that the solid electrolyte layer comprises 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 in a solid-state battery.

[0354] In some embodiments, the solid electrolyte layer comprises the sulfide solid electrolyte described in the first aspect of the present application.

[0355] In some embodiments, the solid electrolyte layer can be pressed from a solid electrolyte material into a solid electrolyte film, which can be a solid electrolyte film sheet or a solid electrolyte film layer.

[0356] In some embodiments, the thickness of the solid electrolyte layer can be 0.1 μm to 1000 μm, optionally 10 μm to 100 μm, 100 μm to 800 μm, 500 μm to 800 μm, etc.

[0357] The following is some description of the positive electrode film and the positive electrode layer.

[0358] In the present application, unless otherwise specified, the "positive electrode film" refers to a film that can be used as a positive electrode of a solid-state battery, and at least comprises a positive electrode active material layer, and usually further comprises a positive electrode current collector.

[0359] The positive electrode layer can be provided by a positive electrode sheet or a positive electrode film sheet known in the art that can be used in a solid-state battery, or the constituent materials of the positive electrode layer can be directly pressed into a positive electrode film layer on one side surface of the solid electrolyte layer. The positive electrode film sheet can be combined with other films suitable for a positive electrode to form a positive electrode sheet or a positive electrode layer.

[0360] The positive electrode layer can be prepared by a dry method or a wet method. For example, the dry method 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, the wet method can be used to coat a positive electrode film, which can be a positive electrode film layer.

[0361] In some embodiments, the positive electrode film comprises a positive electrode current collector and a positive electrode active material layer disposed on at least one surface of the positive electrode current collector, and the definition of the positive electrode active material layer can be referred to the foregoing.

[0362] In some embodiments, the positive electrode current collector can employ a metal foil or a composite current collector. For example, as the metal foil, an aluminum foil can be employed. In the positive electrode current collector, the composite current collector can 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 can be obtained by forming a metal material on a polymer material base material. In the positive electrode current collector, non-limiting examples of the metal material can include one or more of aluminum, an aluminum alloy, nickel, a nickel alloy, titanium, a titanium alloy, silver, a silver alloy, and the like. In the positive electrode current collector, non-limiting examples of the polymer material base material can include one or more of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), polyethylene (PE), and the like.

[0363] Non-limitingly, in the positive electrode film or the positive electrode layer, the thickness of the positive electrode active material layer is 30 μm to 400 μm, can be optionally 60 μm to 130 μm, and can also be any one of the following thicknesses or a range selected from any two of the following thicknesses: 30 μm, 40 μm, 50 μm, 60 μm, 80 μm, 100 μm, 120 μm, 130 μm, 140 μm, 150 μm, 160 μm, 180 μm, 200 μm, and the like.

[0364] In the present application, unless otherwise specified, the "thickness of the positive electrode active material layer" refers to the total thickness in the positive electrode film or the 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 of both sides.

[0365] As a non-limiting example, the positive electrode current collector has two surfaces facing away from each other in the thickness direction thereof, and the positive electrode active material layer is provided on any one or both of the two surfaces of the positive electrode current collector facing away from each other.

[0366] The positive electrode film and the positive electrode layer each include a positive electrode active material layer, and the positive electrode active material layer includes positive electrode active particles containing a positive electrode active material.

[0367] Non-limitingly, the weight percentage of the positive electrode active particles or the positive electrode active material in the positive electrode active material layer can be ≥ 70 wt%, can further be ≥ 80 wt%, can still further be ≥ 90 wt%, and can also be any one of the following weight percentages or a range selected from any two of the following weight percentages: 70 wt%, 75 wt%, 80 wt%, 82 wt%, 84 wt%, 85 wt%, 86 wt%, 88 wt%, 90 wt%, 92 wt%, 94 wt%, 95 wt%, 96 wt%, 97 wt%, 98 wt%, 99 wt%, and the like.

[0368] In some embodiments, the positive electrode active material layer includes positive electrode electrolyte particles. Without limitation, the positive electrode electrolyte particles can have a weight percentage in the positive electrode active material layer of 0.1 wt% to 30 wt%, optionally 5 wt% to 20 wt%, and / or a weight percentage in the positive electrode active material layer of any one of or a range selected from any two of 0.1 wt%, 0.2 wt%, 0.4 wt%, 0.5 wt%, 0.6 wt%, 0.8 wt%, 1 wt%, 1.2 wt%, 1.5 wt%, 1.6 wt%, 1.8 wt%, 2 wt%, 2.5 wt%, 3 wt%, 3.5 wt%, 4 wt%, 5 wt%, 6 wt%, 7 wt%, 8 wt%, 9 wt%, 10 wt%, 12 wt%, 14 wt%, 15 wt%, 16 wt%, 18 wt%, 20 wt%, 22 wt%, 24 wt%, 25 wt%, 26 wt%, 28 wt%, 30 wt%, etc.

[0369] In some embodiments, the positive electrode active material layer includes positive electrode active particles and positive electrode electrolyte particles.

[0370] In some embodiments, the positive electrode active material in the positive electrode active particles can be any positive electrode active material known in the art for use in batteries. Without limitation, the positive electrode active material can include one or more of lithium-containing phosphates of olivine structure, lithium transition metal oxides, and modified compounds of each thereof. However, the present application is not limited to these materials, and other conventional materials that can be used as positive electrode active materials for batteries can also be used. These positive electrode active materials can be used alone or in combination of two or more. Examples of the lithium transition metal oxides can include, without limitation, 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 modified compounds thereof. Non-limiting examples of the lithium-containing phosphates of olivine structure can include, without limitation, one or more of lithium iron phosphate, a composite of lithium iron phosphate and carbon, lithium manganese phosphate, a composite of lithium manganese phosphate and carbon, lithium manganese iron phosphate, a composite of lithium manganese iron phosphate and carbon. Non-limiting examples of the lithium cobalt oxide can include LiCoO2; non-limiting examples of the lithium nickel oxide can include LiNiO2; non-limiting examples of the lithium manganese oxide can include LiMnO2, LiMn2O4, etc.; non-limiting examples of the lithium nickel cobalt manganese oxide can 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 can be referred to as NCM 523 ), LiNi 0.5 Co 0.25 Mn 0.25 O2(also can be referred to as NCM 211 ), LiNi 0.6 Co 0.2 Mn 0.2 O2(also can be referred to as NCM 622 ), LiNi 0.8 Co 0.1 Mn 0.1 O2(also can be referred to as NCM 811 ) and the like. Non-limiting examples of lithium nickel cobalt aluminum oxides can include LiNi 0.80 Co 0.15 Al 0.05 O2. Examples of lithium iron phosphates are LiFePO4(also can be referred to as LFP). Examples of lithium manganese phosphates are LiMnPO4.

[0371] In the case of solid-state batteries with active ions including lithium ions, it can be understood that the solid-state batteries will be accompanied by lithium (Li) deintercalation and consumption during charging and discharging, 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, the content of Li can be the initial state of the material or the non-initial state after charging and discharging cycle unless otherwise specified. When the positive electrode active material is applied to the positive electrode layer in the solid-state battery system, the content of Li in the positive electrode active material contained in the positive electrode layer will usually change after charging and discharging cycle. The content of Li can be measured by atomic molar content, but is not limited thereto. As for "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 appropriately modifying the listed positive electrode active materials are also within the scope of positive electrode active materials, and the aforementioned appropriate modification refers to acceptable modification methods for positive electrode active materials, and non-limiting examples include coating modification. In the exemplary description of the positive electrode active material in this application, the content of oxygen (O) is usually the theoretical state value, and the release of oxygen from the crystal lattice will cause the atomic molar content of oxygen to change, and the actual content of O will fluctuate. The content of O can be measured by atomic molar content, but is not limited thereto.

[0372] In some embodiments, the positive electrode active material layer includes a conductive agent (may be referred to as a positive electrode conductive agent). As a non-limiting example, the positive electrode conductive agent can be a carbon conductive agent. Without limitation, the carbon conductive agent can include one or more of super-P, acetylene black, carbon black, ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers. In some embodiments, the positive electrode conductive agent can include, but is not limited to, one or more of SP, KS-6, acetylene black, branched ketjen black ECP, SFG-6, vapor grown carbon fiber VGCF, carbon nanotubes (CNTs), and graphene, etc. Without limitation, the weight percentage of the positive electrode conductive agent in the positive electrode active material layer can be 0-10 wt%, further can be 0-8 wt%, further can be 0-5 wt%, further can be 0.1 wt%-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 can also be 0.1 wt%-5 wt%, 0.2 wt%-5 wt%, 0.5 wt%-5 wt%, 0.1 wt%-3 wt%, etc.

[0373] In some embodiments, the positive electrode active material layer optionally includes a binder (may be referred to as a positive electrode binder). As a non-limiting example, the positive electrode binder can 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. Generally, the weight percentage of the positive electrode binder in the positive electrode active material layer can be 0-10 wt%, further can be 0-8 wt%, further can be 0.1 wt%-5 wt%, further can be 1 wt%-5 wt%, based on the total weight of the positive electrode active material layer.

[0374] Without limitation, the positive electrode active material layer can include positive electrode active particles, positive electrode electrolyte particles, a positive electrode conductive agent, and a positive electrode binder. The types and amounts of each component can be found in the context of the present application.

[0375] In some embodiments, the positive electrode electrolyte particles include the sulfide solid electrolyte described in the first aspect of the present application.

[0376] In some embodiments, the positive electrode film (which can be used as a positive electrode tab) can be prepared by dry mixing the components described above for preparing the positive electrode film, such as the positive electrode active particles, the positive electrode electrolyte particles, the positive electrode conductive agent, the optional positive electrode binder, and any other components, followed by heating and pressure kneading the mixed material into a dough-like material, hot rolling the dough-like material to form a self-supporting positive electrode tab, and hot roll-complexing the self-supporting positive electrode tab with the positive electrode current collector, which can be on at least one side (single-sided or double-sided) of the positive electrode current collector, to obtain the positive electrode film. Non-limitingly, a double planetary mixer can be used for the dry mixing. Non-limitingly, a Banbury mixer can be used for the heating and pressure kneading. Non-limitingly, the temperature for the hot rolling can be 75-85°C, further such as 78°C, 80°C, 82°C, etc. The method for assembling the solid-state battery using the positive electrode film can be suitable for industrial batch production. A similar method can be used to prepare the negative electrode film or negative electrode tab.

[0377] In some embodiments, the positive electrode film can be prepared by dispersing the components described above for preparing the positive electrode film, such as the positive electrode active particles, the positive electrode electrolyte particles, the positive electrode conductive agent, the positive electrode binder, and any other components, in an organic solvent to form a positive electrode slurry. Further, the positive electrode slurry can be coated on at least one side surface of the positive electrode current collector, and after drying, pressing, etc., the positive electrode film can be obtained. The type of organic solvent in the positive electrode slurry can include one or more of p-xylene, mesitylene, butyl butyrate, heptane, etc., further can be p-xylene. The positive electrode slurry can be coated 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 40-80 wt%. The viscosity of the positive electrode slurry at room temperature can be adjusted to 5000-25000 mPa·s. When coating the positive electrode slurry, the coating unit area density (single-sided) can be 15-35 mg / cm 2 2 3 3 3 3

[0378] ​​​​​​As used herein, "compacted density" has the meaning commonly known in the art as one of the reference indicators of the energy density of a material. In the present 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, positive electrode tab, positive electrode sheet or positive electrode film 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, negative electrode tab, negative electrode sheet or negative electrode film refers to the ratio of the mass of the negative electrode active material layer to its volume.

[0379] Compacted density = Coating area density / Thickness of electrode active material layer.

[0380] Coating area density = Dry weight of slurry / Area of electrode active material layer.

[0381] The double-sided thickness of the electrode active material layer corresponds to the sum of the double-sided coating area densities, and the single-sided thickness corresponds to the single-sided coating area density; when the electrode active material layers on both sides of the current collector are substantially the same, the compacted density can be calculated as follows: Compacted density = Single-sided coating area density / Single-sided thickness of electrode active material layer.

[0382] "Single-sided" and "double-sided" of the electrode active material layer are relative to the position distribution of the current collector.

[0383] The following are some descriptions about the negative electrode film and negative electrode layer.

[0384] In the present application, unless otherwise specified, "negative electrode film" refers to a film capable of being used as a negative electrode of a solid-state battery, which at least includes a negative electrode active material layer, and can further include a negative electrode current collector.

[0385] The negative electrode layer can be provided by a negative electrode tab or negative electrode sheet in the art that can be used for a solid-state battery, or the constituent materials of the negative electrode layer can be directly pressed into a negative electrode film layer on one side surface of the solid electrolyte layer. The negative electrode sheet can be combined with other films suitable for the negative electrode to form a negative electrode tab or negative electrode layer.

[0386] The negative electrode layer can be prepared by dry or wet method. For example, a dry method can be used to press into a negative electrode film, which can be a negative electrode sheet or negative electrode film layer. For another example, a wet coating method can be used to form a negative electrode film, which can be a negative electrode film layer.

[0387] The negative electrode film and negative electrode layer each include a negative electrode active material layer, which includes negative electrode active particles containing a negative electrode active substance. Non-limitingly, the negative electrode active material layer can or can not include negative electrode electrolyte particles.

[0388] In some embodiments, the negative electrode active material layer includes negative electrode electrolyte particles, and further, the negative electrode electrolyte particles can comprise the sulfide solid electrolyte described in the first aspect of the present application.

[0389] Non-limitingly, the weight percentage of the negative active particles or the negative active material in the negative active material layer can be ≥ 80 wt%, further can be ≥ 90 wt%.

[0390] In some embodiments, the negative active particles or the negative active material is a lithium-indium alloy (InLi alloy).

[0391] In some embodiments, the negative layer is an InLi alloy film.

[0392] In some embodiments, the negative active material can also employ the negative active materials known in the art that can be used in solid-state batteries. As non-limiting examples, the negative active material can include one or more of the following materials: one or more of elemental silicon, elemental tin, silicon-carbon negative electrode, silicon monoxide, graphite, metallic lithium. But the present application is not limited to these materials or substances, and other conventional materials that can be used as battery negative active materials can also be used. These negative active materials can be used alone or in combination with two or more.

[0393] In some embodiments, the negative electrode sheet or the negative electrode film can include a negative current collector and a negative active material layer disposed on at least one surface of the negative current collector, the negative active material layer including a negative active material. As non-limiting examples, the negative current collector has two surfaces facing away from each other in the thickness direction thereof, and the negative active material layer is disposed on either one or both of the two surfaces of the negative current collector facing away from each other. In some embodiments, the negative current collector can employ a metal foil or a composite current collector. For example, as a metal foil, a copper foil can be employed. In the negative current collector, the composite current collector can include a polymer material base layer and a metal layer formed on at least one surface of the polymer material base material. In the negative current collector, the composite current collector can be formed by forming a metal material on the polymer material base material. In the negative current collector, non-limiting examples of the metal material can include one or more of copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver, silver alloy, and the like. In the negative current collector, non-limiting examples of the polymer material base material can include one or more of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), polyethylene (PE), and the like.

[0394] In some embodiments, the negative active material layer can optionally include a conductive agent, denoted as a negative conductive agent. Non-limitingly, the negative conductive agent can include one or more of super P, acetylene black, carbon black, ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers. In the negative active material layer, the weight percentage of the negative conductive agent can be 0-10 wt%, further can be optionally 0-5 wt%, further can be optionally 0.1 wt%-5 wt%, further can be optionally 0.1 wt%-3 wt%.

[0395] In some embodiments, the negative active material layer optionally comprises a binder (denoted as negative binder). As non-limiting examples, the negative binder can comprise 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. Non-limitingly, the weight percentage of the negative binder in the negative active material layer can be 0-10 wt%, further can be 0-5 wt%, further can be 1 wt%-5 wt%, further can be 1 wt%-3 wt%.

[0396] In some embodiments, the negative active material layer optionally comprises other auxiliary agents, such as thickening agents (e.g., sodium carboxymethyl cellulose (CMC-Na)) and the like. The weight percentage of the other auxiliary agents in the negative active material layer can be 0-15 wt%, further can be 0-10 wt%, further can be 0-5 wt%, further can be 0-3 wt%, further can be 0-2 wt%.

[0397] In some embodiments, the negative film sheet (which can serve as a negative electrode sheet) can be prepared by dry mixing the components for preparing the negative film sheet, such as the negative active particles, the optional negative electrolyte particles, the negative conductive agent, the optional negative binder, and any other components, and then heating and press kneading the mixed material into a mass, and hot rolling the mass to form a self-supporting negative electrode sheet, and hot rolling the self-supporting negative electrode sheet with the negative current collector, the self-supporting negative electrode sheet can be attached to at least one side (single side or double sides) of the negative current collector to obtain the negative film sheet. Non-limitingly, a double planetary mixer can be used for dry mixing. Non-limitingly, a banbury mixer can be used for heating and press kneading. The method for assembling the solid-state battery using the negative film sheet can be suitable for industrial batch production. When the negative material is prepared into a negative active material layer by dry method, the negative conductive agent can be arranged in the negative material, which can improve the electronic conductivity of the negative active material layer.

[0398] In some embodiments, the negative electrode sheet or the negative electrode film can be prepared by dispersing the above-mentioned components for preparing the negative electrode sheet or the negative electrode film, such as the negative electrode active particles, the optional negative electrode electrolyte particles, the negative electrode conductive agent, the negative electrode binder, and any other components, in a solvent (a non-limiting example of the solvent is p-xylene) to form a negative electrode slurry. Further, the negative electrode slurry is coated on at least one side surface of the negative electrode current collector, and after processes such as drying, pressing, etc., the negative electrode sheet or the negative electrode film is obtained. The surface of the negative electrode current collector to which the negative electrode slurry is coated can be a single surface of the negative electrode current collector, or can be both surfaces of the negative electrode current collector. The solid content of the negative electrode slurry can be 30 wt% to 70 wt%, and optionally 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, and optionally 3000 mPa·s to 10000 mPa·s. When the negative electrode slurry is coated, the coating unit area density (single side) based on the dry weight (excluding the solvent) can be 1.5 mg / cm 2 ~ 18 mg / cm 2 , but is not limited thereto. The compaction density of the negative electrode sheet or the negative electrode film can be 1.0 g / cm 3 ~ 2.0 g / cm 3 , and optionally 1.0 g / cm 3 ~ 1.8 g / cm 3 .

[0399] Non-limitingly, the positive electrode sheet, the solid electrolyte film, and the negative electrode sheet can be sequentially stacked, with the solid electrolyte film being disposed between the positive electrode sheet and the negative electrode sheet, and a solid-state battery cell can be prepared by hot rolling.

[0400] Non-limitingly, the positive electrode film, the solid electrolyte film, and the negative electrode film can be sequentially stacked, with the solid electrolyte film being disposed between the positive electrode film and the negative electrode film, and a solid-state battery cell can be prepared by hot rolling.

[0401] In some embodiments, the solid-state battery cell 5 comprises a solid-state battery cell 52.

[0402] In some embodiments, the solid-state battery cell is a full solid-state battery cell.

[0403] In some embodiments, the solid-state battery cell 52 (which can be a full solid-state battery cell) comprises a positive electrode layer 200, a solid electrolyte layer 100, and a negative electrode layer 300 which are sequentially stacked, and one example can be referred to FIG. 1.

[0404] In some embodiments, the solid-state battery can comprise an outer package. The outer package can be used to package the above-mentioned solid-state battery cell.

[0405] In some embodiments, the outer package 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 package of the solid-state battery can also be a soft package, such as a pouch soft package. The material of the soft package can be plastic, and further, non-limiting examples of the plastic can include one or more of polypropylene, polybutylene terephthalate, and polybutylene succinate, etc.

[0406] The shape of the solid-state battery cell is not particularly limited in the present application, and can be cylindrical, square, or any other shape. For example, FIG. 2 is a solid-state battery cell 5 in a square structure as an example.

[0407] In some embodiments, referring to FIG. 3, the outer package can include a shell 51 and a cover plate 53. The shell 51 can include a bottom plate and a side plate connected to the bottom plate, and the bottom plate and the side plate enclose a receiving cavity. The shell 51 has an opening communicating with the receiving cavity, and the cover plate 53 can be arranged on the opening to close the receiving cavity. The solid-state battery cell 52 is packaged 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, which can be selected by those skilled in the art according to actual needs.

[0408] The solid-state battery can be a battery module 4 or a battery pack 1.

[0409] 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, which can be selected by those skilled in the art according to the application and capacity of the battery module.

[0410] FIG. 4 is a battery module 4 as an example. Referring to FIG. 4, in the battery module 4, a plurality of solid-state battery cells 5 can be arranged in sequence along the length direction of the battery module 4. Of course, other arrangements can also be used. Further, the plurality of solid-state battery cells 5 can be fixed by fasteners.

[0411] Optionally, the battery module 4 can also include a housing having a receiving space, and the plurality of solid-state battery cells 5 are received in the receiving space.

[0412] In some embodiments, the above-mentioned battery module can also be assembled into a battery pack, and the number of battery modules contained in the battery pack can be one or more, which can be selected by those skilled in the art according to the application and capacity of the battery pack.

[0413] FIGS. 5 and 6 are a battery pack 1 as an example. Referring to FIGS. 5 and 6, the battery pack 1 can include a battery box and a plurality of battery modules 4 arranged in the battery box. The battery box includes an upper box body 2 and a lower box body 3, and the upper box body 2 can be arranged on the lower box body 3 to form a closed space for receiving the battery modules 4. The plurality of battery modules 4 can be arranged in the battery box in any manner.

[0414] In some embodiments, the power consuming device comprises the solid-state battery of any of the embodiments provided herein.

[0415] Without limitation, the solid-state battery can be used as a power source of the power consuming device, or as an energy storage unit of the power consuming device. The power consuming device can include a mobile device, an electric vehicle, an electric train, a ship and a satellite, an energy storage system, etc., but is not limited thereto. Among them, the mobile device can be a mobile phone, a notebook computer, etc., for example; the electric vehicle can be a pure electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, an electric bicycle, an electric scooter, an electric golf cart, an electric truck, an electric motorcycle, an electric tool, etc., but is not limited thereto. The power consuming device can also be applied to military equipment, aerospace, etc., and can also be applied to hydroelectric, thermal, wind and solar power plants, etc. energy storage power systems.

[0416] As the power consuming device, the solid-state battery can be selected according to the use requirements thereof.

[0417] FIG. 7 is a power consuming device 6 as an example. The power consuming device is a pure electric vehicle, a hybrid electric vehicle, or a plug-in hybrid electric vehicle, etc. In order to meet the requirements of the power consuming device for high power and high energy density of the solid-state battery, a battery pack or a battery module can be used.

[0418] The device as another example can be a mobile phone, a tablet computer, a notebook computer, etc. The device usually requires thinning, and a solid-state battery can be used as a power source.

[0419] Hereinafter, some embodiments of the present application are described. The embodiments described below are exemplary and are only used to explain the present application, and cannot be understood as a limitation of the present application. The technical or conditions not mentioned in the embodiments are carried out according to the description in the foregoing, or according to the technology or conditions described in the literature in the art, or according to the product manual. The reagents or instruments used without mentioning the manufacturer are all conventional products that can be obtained by market purchase, or can be synthesized by market products according to the conventional method.

[0420] In the following examples, room temperature refers to 20-30°C.

[0421] In each of the following examples, unless otherwise specified, the amount of "sulfur element" expressed in wt% refers to the weight percentage in the sintered mixture; in each of the following preparation examples, unless otherwise specified, the sintered mixture is the precursor mixture; in each of the following preparation comparative examples, unless otherwise specified, the sintered mixture is the raw material mixture.

[0422] It should be noted that the sulfide all-solid-state battery is used as a non-limiting example of the solid-state battery in each of the following embodiments and examples.

[0423] I. Preparation of sulfide solid electrolyte

[0424] Preparation Example 1. A sulfide solid electrolyte was prepared according to the chemical formula Li 10.5 Sn 1.5 P 1.5 S 12 stoichiometrically weighed Li2S, P2S5, and SnS2powder, and additionally weighed 3wt% of elemental sulfur, mixed, to obtain a precursor mixture, and the precursor mixture was sintered at 600°C for 8h in an inert atmosphere (argon) furnace, and then the sintered body was crushed to obtain a sulfide solid electrolyte powder.

[0425] Preparation Example 2. A sulfide solid electrolyte was prepared according to the chemical formula Li 10.7 Sn 1.7 P 1.3 S 12 stoichiometrically weighed Li2S, P2S5, and SnS2powder, and additionally weighed 3wt% of elemental sulfur, mixed, to obtain a precursor mixture, and the precursor mixture was sintered at 580°C for 8h in an inert atmosphere (argon) furnace, and then the sintered body was crushed to obtain a sulfide solid electrolyte powder.

[0426] Preparation Example 3. A sulfide solid electrolyte was prepared using substantially the same method as in Preparation Example 2, except that the target chemical formula for adjusting the stoichiometric ratio of raw materials was Li 10.1 Sn 1.1 P 1.9 S 12 .

[0427] Preparation Example 4. A sulfide solid electrolyte was prepared according to the chemical formula Li 10.5 Sn 1.5 P 1.3 Sb 0.2 S 12 stoichiometrically weighed Li2S, P2S5, Sb2S3, S, and SnS2powder, and additionally weighed 3wt% of elemental sulfur, mixed, to obtain a precursor mixture, and the precursor mixture was sintered at 580°C for 8h in an inert atmosphere (argon) furnace, and then the sintered body was crushed to obtain a sulfide solid electrolyte powder.

[0428] Preparation Example 5. A sulfide solid electrolyte was prepared according to the chemical formula Li 10.5 Sn 1.5 P 1.1 Sb 0.4 S 12, stoichiometrically weighed Li2S, P2S5, Sb2S3, S and SnS2powder, and additionally weighed 3wt% of sulfur element, mixed, to obtain a precursor mixture, and the precursor mixture was sintered at 560°C for 8h in an inert atmosphere (argon) furnace, and then the sintered body was crushed to obtain a sulfide solid electrolyte powder.

[0429] Example 6. A sulfide solid electrolyte was prepared using substantially the same method as in Preparation Example 5, except that the target chemical formula for regulating the stoichiometric ratio of raw materials was Li 10.7 Sn 1.7 P 0.9 Sb 0.4 S 12 , and the sintering temperature was changed to 540°C.

[0430] Example 7. A sulfide solid electrolyte was prepared using substantially the same method as in Preparation Example 5, except that the target chemical formula for regulating the stoichiometric ratio of raw materials was Li 10.1 Sn 1.1 P 1.5 Sb 0.4 S 12 , and the sintering temperature was changed to 570°C.

[0431] Preparation Example 8. A sulfide solid electrolyte was prepared according to the chemical formula Li 10.5 Sn 1.5 P 1.5 S 10.5 O 1.5 , stoichiometrically weighed Li2S, P2S5, P2O5and SnS2powder, and additionally weighed 3wt% of sulfur element, mixed, to obtain a precursor mixture, and the precursor mixture was sintered at 600°C for 8h in an inert atmosphere (argon) furnace, and then the sintered body was crushed to obtain a sulfide solid electrolyte powder.

[0432] Preparation Example 9. A sulfide solid electrolyte was prepared according to the chemical formula Li 10.5 Sn 1.5 P 1.5 S 9.1 O 2.9 , stoichiometrically weighed Li2S, P2S5, P2O5and SnS2powder, and additionally weighed 3wt% of sulfur element, mixed, to obtain a precursor mixture, and the precursor mixture was sintered at 620°C for 8h in an inert atmosphere (argon) furnace, and then the sintered body was crushed to obtain a sulfide solid electrolyte powder.

[0433] Preparation Example 10. A sulfide solid electrolyte was prepared using substantially the same method as in Preparation Example 9, except that the target chemical formula for regulating the stoichiometric ratio of raw materials was Li 10.7 Sn 1.7 P1.3 S 9.1 O 2.9 , the sintering temperature is changed to 560°C.

[0434] Preparation Example 11. A sulfide solid electrolyte is prepared in substantially the same manner as in Preparation Example 9, except that the target chemical formula for controlling the stoichiometric ratio of raw materials is Li 10.1 Sn 1.1 P 1.9 S 9.1 O 2.9 , the sintering temperature is changed to 600°C.

[0435] Preparation Example 12. A sulfide solid electrolyte is prepared in substantially the same manner as in Preparation Example 11, except that the target chemical formula for controlling the stoichiometric ratio of raw materials is Li 10.2 Sn 1.5 P 1.5 S 11.7 Cl 0.3 , stoichiometrically appropriate amounts of Li2S, P2S5, LiCl, and SnS2powder are weighed, and 3 wt% of elemental sulfur is additionally weighed, mixed, and a precursor mixture is obtained. The precursor mixture is placed in an inert atmosphere (argon) furnace and sintered at 550°C for 8 hours, and then the sintered body is crushed to obtain a sulfide solid electrolyte powder.

[0436] Preparation Example 13. A sulfide solid electrolyte is prepared in substantially the same manner as in Preparation Example 12, except that the target chemical formula for controlling the stoichiometric ratio of raw materials is Li 10 Sn 1.5 P 1.5 S 11.5 Cl 0.5 , stoichiometrically appropriate amounts of Li2S, P2S5, LiCl, and SnS2powder are weighed, and 3 wt% of elemental sulfur is additionally weighed, mixed, and a precursor mixture is obtained. The precursor mixture is placed in an inert atmosphere (argon) furnace and sintered at 530°C for 8 hours, and then the sintered body is crushed to obtain a sulfide solid electrolyte powder.

[0437] Preparation Example 14. A sulfide solid electrolyte is prepared in substantially the same manner as in Preparation Example 13, except that the target chemical formula for controlling the stoichiometric ratio of raw materials is Li 10.2 Sn 1.7 P 1.3 S 11.5 Cl 0.5 .

[0438] Preparation Example 15. A sulfide solid electrolyte is prepared in substantially the same manner as in Preparation Example 13, except that the target chemical formula for controlling the stoichiometric ratio of raw materials is Li 9.6 Sn 1.1 P 1.9 S 11.5 Cl 0.5 , the sintering temperature is changed to 550°C.

[0439] 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 The stoichiometrically appropriate amounts of Li2S, P2S5, Sb2S3, S, P2O5, and SnS2powdered raw materials were weighed out separately, and 3 wt% of elemental sulfur was additionally weighed out, mixed, and a precursor mixture was obtained. The precursor mixture was sintered at 580°C for 8 hours in an inert atmosphere (argon) furnace, and then the sintered body was crushed to obtain a sulfide solid electrolyte powder.

[0440] 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 The stoichiometrically appropriate amounts of Li2S, P2S5, Sb2S3, S, LiCl, and SnS2powdered raw materials were weighed out separately, and 3 wt% of elemental sulfur was additionally weighed out, mixed, and a precursor mixture was obtained. The precursor mixture was sintered at 550°C for 8 hours in an inert atmosphere (argon) furnace, and then the sintered body was crushed to obtain a sulfide solid electrolyte powder.

[0441] 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 The stoichiometrically appropriate amounts of Li2S, P2S5, LiCl, P2O5, and SnS2powdered raw materials were weighed out separately, and 3 wt% of elemental sulfur was additionally weighed out, mixed, and a precursor mixture was obtained. The precursor mixture was sintered at 550°C for 8 hours in an inert atmosphere (argon) furnace, and then the sintered body was crushed to obtain a sulfide solid electrolyte powder.

[0442] 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 The stoichiometrically appropriate amounts of Li2S, P2S5, SnS2, Sb2S3, S, LiCl, P2O5, and powdered raw materials were weighed out separately, and 3 wt% of elemental sulfur was additionally weighed out, mixed, and a precursor mixture was obtained. The precursor mixture was sintered at 540°C for 8 hours in an inert atmosphere (argon) furnace, and then the sintered body was crushed to obtain a sulfide solid electrolyte powder.

[0443] 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 The stoichiometric amounts of Li2S, P2S5, SnS2, Sb2S3, S, LiCl, P2O5, and raw material powders were weighed, respectively, and 3 wt% of elemental sulfur was additionally weighed, mixed, and a precursor mixture was obtained. The precursor mixture was sintered at 540°C for 8h in an inert atmosphere (argon) furnace, and then the sintered body was crushed to obtain a sulfide solid electrolyte powder.

[0444] Preparation Comparative Example 1. According to the chemical formula Li 10 SnP2S 12 The stoichiometric amounts of Li2S, P2S5, and SnS2 raw material powders were weighed, respectively, and 3 wt% of elemental sulfur was additionally weighed, mixed, and a raw material mixture was obtained. The raw material mixture was sintered at 600°C for 8h in an inert atmosphere (argon) furnace, and then the sintered body was crushed to obtain a sulfide solid electrolyte powder.

[0445] Preparation Comparative Example 2. According to the chemical formula Li 10 SnP 1.8 Sb 0.2 S 12 The stoichiometric amounts of Li2S, P2S5, Sb2S3, S, and SnS2 raw material powders were weighed, respectively, and 3 wt% of elemental sulfur was additionally weighed, mixed, and a raw material mixture was obtained. The raw material mixture was sintered at 580°C for 8h in an inert atmosphere (argon) furnace, and then the sintered body was crushed to obtain a sulfide solid electrolyte powder.

[0446] Preparation Comparative Example 3. According to the chemical formula Li 10 SnP2S 10.5 O 1.5 The stoichiometric amounts of Li2S, P2S5, P2O5, and SnS2 raw material powders were weighed, respectively, and 3 wt% of elemental sulfur was additionally weighed, mixed, and a raw material mixture was obtained. The raw material mixture was sintered at 600°C for 8h in an inert atmosphere (argon) furnace, and then the sintered body was crushed to obtain a sulfide solid electrolyte powder.

[0447] Preparation Comparative Example 4. According to the chemical formula Li 9.7 SnP2S 11.7 Cl 0.3, respectively, stoichiometrically weighed Li2S, P2S5, LiCl and SnS2 raw material powders, additionally weighed 3wt% of elemental sulfur, mixed to obtain a raw material mixture, and the raw material mixture was placed in an inert atmosphere (argon) furnace and sintered at 550°C for 8h, and then the sintered body was crushed to obtain a sulfide solid electrolyte powder.

[0448] Preparation Comparative Example 5. Includes a cation-substituted element, but the cation-substituted element does not include either of Sb element and Sn element.

[0449] According to the chemical formula Li 10.5 Sn 1.5 P 1.3 Ge 0.2 S 12 , respectively, stoichiometrically weighed Li2S, P2S5, LiCl and SnS2 raw material powders, additionally weighed 3wt% of elemental sulfur, mixed to obtain a raw material mixture, and the raw material mixture was placed in an inert atmosphere (argon) furnace and sintered at 550°C for 8h, and then the sintered body was crushed to obtain a sulfide solid electrolyte powder.

[0450] Preparation Comparative Example 5 replaces Sb element with Ge element with respect to Preparation Example 4.

[0451] Preparation Comparative Example 6. Includes an anion-substituted element, but the anion-substituted element does not include either of O element and Cl element.

[0452] According to the chemical formula Li 10.2 Sn 1.5 P 1.5 S 11.7 Br 0.3 , respectively, stoichiometrically weighed Li2S, P2S5, LiCl and SnS2 raw material powders, additionally weighed 3wt% of elemental sulfur, mixed to obtain a raw material mixture, and the raw material mixture was placed in an inert atmosphere (argon) furnace and sintered at 550°C for 8h, and then the sintered body was crushed to obtain a sulfide solid electrolyte powder.

[0453] Preparation Comparative Example 6 replaces Cl element with Br element with respect to Preparation Example 12.

[0454] In Preparation Examples 1-20, when referring to a cation-substituted element, at least one of Sb element and Sn element is taken as an example, and when referring to an anion-substituted element, one or both of O element and Cl element is taken as an example.

[0455] The target chemical formula of the sulfide solid electrolyte prepared in Preparation Examples 1-20 and Preparation Comparative Examples 1-6 can be referred to Table 1; the atomic number ratio between various elements in the LGPS-type crystal phase calculated according to the chemical formula in Table 1 can be referred to Table 2: the atomic number ratio between the cation-substituted element and P element (RY / P ), the atomic number ratio of the anion-substituted element and the S element (R N / S ), the atomic number ratio of the Sn element and the S element (R Sn / S ), the atomic number ratio of the Sn element and the P element (R Sn / P ), the atomic number ratio of the Sb element and the S element (R Sb / S ), the atomic number ratio of the Sb element and the P element (R Sb / P ), the atomic number ratio of the sum of the Sn element and the Sb element to the S element (R (Sn+Sb) / S ), the atomic number ratio of the sum of the Sn element and the Sb element to the P element (R (Sn+Sb) / P ), the atomic number ratio of the O element and the S element (R O / S ), and the atomic number ratio of the Cl element and the S element (R Cl / S ). See also the definitions described above.

[0456] In Preparation Comparative Example 5, the atomic number ratio of the Ge element and the S element is denoted as R Ge / S , the atomic number ratio of the Ge element and the P element is denoted as R Ge / P , the atomic number ratio of the sum of the Sn element and the Ge element to the S element is denoted as R (Sn+Ge) / S , the atomic number ratio of the sum of the Sn element and the Ge element to the P element is denoted as R (Sn+Ge) / P .

[0457] In Preparation Comparative Example 6, R Br / S represents the atomic number ratio of the bromine (Br) element and the S element.

[0458] Table 1. Target chemical formula of sulfide solid electrolytes prepared in Preparation Examples 1-20 and Preparation Comparative Examples 1-6

[0459] Table 2.

[0460] According to Table 2, R Y / P is equal in value to R Sb / P , R N / S is equal in value to R O / S , and R Cl / S is equal in value to the sum of R 811 .

[0461] In each of the following examples, unless otherwise specified, operations or reaction steps involving sulfide solid electrolyte materials as raw materials are performed in an argon atmosphere.

[0462] In each of the following examples, unless otherwise specified, the positive active particles NCM 811 powder has a D v 50 of 4 pm (the positive active material is NCM811 D50 of sulfide solid electrolyte Li6PS5Cl v 50 is 1 μm.

[0463] In the present application, D50 of the positive active particles and the sulfide solid electrolyte, unless otherwise specified, v 50 represents the particle size corresponding to the cumulative volume distribution percentage of 50% of the multi-particle mixture.

[0464] D50 of sulfide solid electrolyte Li6PS5Cl v 50 is tested as follows:

[0465] In the following examples and comparative examples, D50 of the positive active particles and the sulfide solid electrolyte, v 50 is tested and confirmed as follows: equipment model: MasterSizer 2000 laser particle size analyzer, reference standard process: GB / T19077-2016 / ISO 13320:2009, test process: an appropriate amount of sample to be tested (sample concentration is ensured to be 8%-12% (w / v) optical density) is added with 20 mL of p-xylene (when testing the sulfide solid electrolyte, a dispersant ammonium polycarboxylate is also added), and at the same time, the outside is superimposed for 5 min (53 KHz / 120 W) to ensure that the sample is completely dispersed, and then the sample is measured according to the GB / T19077-2016 / ISO 13320:2009 standard.

[0466] II. The solid electrolyte layer is provided with the sulfide solid electrolyte provided in the present application, and the preparation of the solid-state battery (all-solid-state secondary battery, sulfide all-solid-state battery).

[0467] 1. Preparation of solid electrolyte film (in the form of solid electrolyte film sheet)

[0468] Examples 1-20 (corresponding to the sulfide solid electrolyte powder of Preparation Examples 1-20, respectively):

[0469] In an argon atmosphere, the sulfide solid electrolyte powder (obtained by Preparation Examples 1-20) is pressed into a dense solid electrolyte film sheet under the action of 360 MPa.

[0470] In an argon atmosphere, the NCM811 powder, the sulfide solid electrolyte Li6PS5Cl, and the conductive carbon fiber (VGCF) are manually ground in a mortar for 10 min at a weight ratio of 70:28:2 until they are uniformly mixed, to obtain a composite positive electrode powder. The composite positive electrode powder is uniformly spread on one side surface of the solid electrolyte film sheet, and cold-pressed into a sheet at a pressure of 420 MPa for 5 min, to form a composite film sheet composed of a positive electrode layer and a solid electrolyte layer. An InLi alloy is laminated on the other side of the solid electrolyte film sheet as a negative electrode layer, to assemble a full-solid-state battery. At this time, the solid electrolyte film sheet serves as the solid electrolyte layer, and the positive electrode film sheet serves as the positive electrode layer.

[0471] Comparative Examples 1-6:

[0472] The same method as in Example 1 was used, except that the sulfide solid electrolyte powder used for preparing the solid electrolyte membrane was replaced with the sulfide solid electrolyte powder prepared in Comparative Examples 1-6.

[0473] III. Preparation of a solid-state battery (all-solid-state secondary battery, sulfide all-solid-state battery) provided with the sulfide solid electrolyte according to the present application.

[0474] Examples P1 to P20 (corresponding to the sulfide solid electrolyte powder of Preparation Examples 1-20, respectively):

[0475] In an argon atmosphere, the positive electrode active particles NCM811 powder, the sulfide solid electrolyte powder (prepared in Preparation Examples 1-20, as positive electrode electrolyte particles), and the conductive carbon fiber (VGCF, as positive electrode conductive agent) were manually ground in a mortar at a weight ratio of 70:28:2 for 10 min until they were uniformly mixed, obtaining a composite positive electrode powder.

[0476] In an argon atmosphere, the sulfide solid electrolyte powder Li6PS5Cl was pressed into a dense solid electrolyte membrane under the action of 360 MPa.

[0477] The composite positive electrode powder was weighed and uniformly spread on one side surface of the solid electrolyte membrane, and cold-pressed into a sheet at a pressure of 420 MPa for 5 min, forming a composite membrane composed of a positive electrode layer and a solid electrolyte layer. On the other side of the solid electrolyte membrane, an InLi alloy was laminated as a negative electrode layer, to assemble an all-solid-state battery. At this time, the solid electrolyte membrane serves as the solid electrolyte layer, and the positive electrode membrane serves as the positive electrode layer.

[0478] Comparative Example P1.

[0479] The same method as in Example P3 was used to prepare an all-solid-state battery, except that the positive electrode electrolyte particles in the composite positive electrode powder were replaced with Li7P2S8Cl2 prepared in Comparative Example 1. 10 SnP2S 12 .

[0480] IV. Preparation of a solid-state battery (all-solid-state secondary battery, sulfide all-solid-state battery) provided with the sulfide solid electrolyte according to the present application.

[0481] Examples N1 to N20 (corresponding to the sulfide solid electrolyte powder of Preparation Examples 1-20, respectively):

[0482] In an argon atmosphere, the sulfide solid electrolyte powder Li6PS5Cl was pressed into a dense solid electrolyte membrane under the action of 360 MPa.

[0483] The NCM811 powder, sulfide solid electrolyte Li6PS5Cl, and conductive carbon fiber (VGCF) were manually ground in a mortar for 10 min in an argon atmosphere at a weight ratio of 70:28:2 until they were uniformly mixed, to obtain a composite cathode powder. The composite cathode powder was uniformly spread on one side surface of the solid electrolyte membrane, and cold-pressed to form a sheet at a pressure of 420 MPa for 5 min, to form a composite membrane composed of a cathode layer and a solid electrolyte layer.

[0484] In an argon atmosphere, the negative electrode active particles Si powder, sulfide solid electrolyte powder (prepared in Preparation Example 1-20, as negative electrode electrolyte particles), and negative electrode binder PVDF were dispersed in a solvent p-xylene (solid content 60 wt%) at a weight ratio of 80:17:3, and coated on the surface of the solid electrolyte membrane at a coating surface density of 2.5 mg / cm2(dry weight basis (excluding solvent)). 2 The other side of the solid electrolyte layer in the composite membrane was coated with a negative electrode layer, and dried to form a full-solid-state battery including a cathode layer (corresponding to the cathode 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.

[0485] Comparative Example N1.

[0486] A full-solid-state battery was prepared by substantially the same method as in Example N3, except that the negative electrode electrolyte particles in the negative electrode layer were replaced with Li7PS6 prepared in Comparative Example 1. 10 SnP2S 12 .

[0487] The preparation parameters and test results of the partial examples and comparative examples in the second, third, and fourth parts can be seen in Table 4.

[0488] V. Test and analysis of materials

[0489] (I) Test and analysis method

[0490] 1. Elemental analysis

[0491] An inductively coupled plasma spectrometer (ICP instrument) was used to analyze the types and proportions of elements of the sulfide solid electrolyte, to determine its chemical formula.

[0492] Test instrument: ThermoFisher ICAP Pro.

[0493] 2. Crystal phase analysis

[0494] X-ray diffraction (XRD) was used to determine whether the sulfide solid electrolyte included an LGPS-type crystal phase and the amount of impurities.

[0495] Sample to be tested: sulfide solid electrolyte powder.

[0496] Test instrument: Bruker-D8 advance. Cu target Kα1 ray was used, wavelength λ was 0.15406 nm, X-ray tube was controlled at 40 kV and 40 mA, 2θ(°) scanning range was 10°-80°, 2θ(°) scanning speed was 0.02° / second.

[0497] Analysis method: According to the comparison with the XRD standard spectrum of Li 10 GeP2S 12 The XRD standard spectrum of LGPS was used to confirm whether the sulfide solid electrolyte to be tested included LGPS type crystal phase.

[0498] 3. Hydrogen sulfide (H2S) release amount test

[0499] Test sample: Sulfide solid electrolyte powder.

[0500] Test method: 100 mg of the solid electrolyte powder to be tested was evenly spread in a petri dish with a diameter of 5 cm in a dew point environment of minus 55°C, then the petri dish containing the solid electrolyte powder was placed in a 50 L box through a sealed transfer box, the sealed transfer box containing the solid electrolyte powder was quickly opened in the box, and the 50 L box was closed, a hydrogen sulfide sensor (PGM-2500) was placed in the box to record the cumulative value of hydrogen sulfide in the 50 L box in real time, and the reaction continued until the detection value of the hydrogen sulfide sensor no longer increased, indicating that the electrolyte was completely reacted with the water molecules in the box; at the same time, a fan with a blade diameter of 8 cm was placed in the box, because the density of hydrogen sulfide is larger than that of air, the fan can prevent the hydrogen sulfide gas from settling and make the hydrogen sulfide gas in the 50 L box evenly distributed, and the hydrogen sulfide gas concentration test has high reliability. Before testing, the 50 L box was placed in an environment with a relative humidity of 70% R.H.

[0501] The sulfide solid electrolyte powder prepared in Preparation Example 1-20 corresponds to Test Example 1-20, respectively; the sulfide solid electrolyte powder prepared in Preparation Comparative Example 1-6 corresponds to Test Comparative Example 1-6, respectively; the test results can be referred to Table 3 "Hydrogen sulfide release amount".

[0502] 4. Ion conductivity test

[0503] Ion conductivity was determined by the alternating current impedance spectroscopy (EIS) method.

[0504] Test sample: Sulfide solid electrolyte powder

[0505] Test sample preparation: 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 round tablet at 360 MPa to obtain a solid electrolyte membrane as a test sample.

[0506] Test method: The prepared solid electrolyte membrane was clamped in a mold with a 10 mm diameter cylindrical stainless steel current collector at 120 MPa, and then the current collector was connected to an electrochemical workstation. Electrochemical impedance spectroscopy (EIS) was performed on the electrolyte sheet at a bias of 10 mV and a frequency range of 10 6 Hz to 10 Hz. The intersection of the curve in the electrochemical impedance spectrum from high frequency to low frequency with the Z' axis was recorded as the resistance R, and the ionic conductivity (σ) was calculated by formula (1):

[0507] where d is the thickness of the solid electrolyte membrane, and A is the contact area of the electrolyte sheet and the current collector.

[0508] 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 seen in Table 3 "Ionic conductivity".

[0509] 5. Battery cycle performance test

[0510] The assembled battery to be tested was first activated by charging and discharging at 0.1C for 3 cycles, and then long cycle test was performed at 0.33C charging and discharging, and the cycle capacity retention rate of the battery was calculated. The voltage test window of the battery was 2.8-4.3V vs. Li + / Li (lithium potential, active ion is Li + ), and the battery was tested at 25±3°C, wherein 1C=200mA / g. The test results can be seen in Table 4 "200 cycle capacity retention rate, 0.33C".

[0511] (II) Analysis of test results

[0512] 1. Elemental analysis

[0513] ICP test confirmed that the chemical formula of the sulfide solid electrolyte prepared in each of Preparation Examples 1-20 and each of Preparation Comparative Examples 1-6 was basically consistent with the target chemical formula. Taking Example 1 as an example, the actual test results of the elemental composition of the target sulfide solid electrolyte Li 10.5 Sn 1.5 P 1.5 S 12 were as follows: the atomic number ratio of Li:Sn:P:S was 10.52:1.49:1.48:11.89.

[0514] 2、According to the XRD analysis results, the sulfide solid electrolytes prepared in each of Preparation Examples 1-20 and each of Preparation Comparative Examples 1-6 all form LGPS-type crystal phases. In addition, the content of the impurity phase in each of the Preparation Examples is relatively low. As an example, the X-ray diffraction (XRD) pattern of the sulfide solid electrolyte prepared in Preparation Example 1 and Preparation Comparative Example 1 can be seen in FIG. 8.

[0515] 3、Hydrogen sulfide release amount and ionic conductivity

[0516] The test results of the hydrogen sulfide release amount and the ionic conductivity of the sulfide solid electrolytes prepared in each of Preparation Examples 1-20 and each of Preparation Comparative Examples 1-6 can be seen in Table 3.

[0517] Compared with Preparation Comparative Examples 1-4, the sulfide solid electrolytes of Preparation Examples 1-20 satisfy the following characteristics: (1) the atomic number ratio (R Sn / S ) of Sn element and S element is greater than 1 / 12; and (2) the atomic number ratio (R Sn / P ) of Sn element and P element is greater than 1 / 2.

[0518] Compared with Preparation Comparative Examples 1-4, the sulfide solid electrolytes prepared in each of Preparation Examples 1-20 have a significantly reduced hydrogen sulfide release amount, while also having good ionic conductivity.

[0519] In each of the Preparation Examples, a lower hydrogen sulfide release amount indicates that the sulfide solid electrolyte has better chemical stability, and in addition, a lower content of the impurity phase is also conducive to improving the ionic conductivity of the sulfide solid electrolyte.

[0520] The LGPS-type crystal phase of the sulfide solid electrolyte of Test Comparative Example 5 includes a cation substitution element, but the cation substitution element does not include any one of Sb element and Sn element, and the cation 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.

[0521] 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 any one of O element and Cl, and the anion substitution element is Br. Compared with Test Example 12, the hydrogen sulfide release amount of Test Comparative Example 6 is significantly increased.

[0522] 4、Battery cycle performance

[0523] The solid-state batteries prepared in Examples 1-20, Examples P1-P20, and Examples N1-N20 all have good cycle performance. Among them, Examples 1-20 are provided with the sulfide solid electrolyte provided in the first aspect of the present application in the solid electrolyte layer, Examples P1-P20 are provided with the sulfide solid electrolyte provided in the first aspect of the present application in the positive electrode layer, and Examples N1-N20 are provided with the sulfide solid electrolyte provided in the first aspect of the present application in the negative electrode layer.

[0524] For example, compared with Examples 1-20, the cycle performance of the solid electrolyte layer of Comparative Example 1, which is not provided with the sulfide solid electrolyte provided in the first aspect of the present application, is obviously deteriorated; compared with Examples 4, 8 and 12, the cycle performance of the solid electrolyte layer of Comparative Examples 2-4, which is not provided with the sulfide solid electrolyte provided in the first aspect of the present application, is obviously deteriorated; compared with Example 4, the cycle performance of Comparative Example 5, which is not provided with the sulfide solid electrolyte provided in the first aspect of the present application, is obviously deteriorated; compared with Example 2, the cycle performance of Comparative Example 6, which is not provided with the sulfide solid electrolyte provided in the first aspect of the present application, is obviously deteriorated.

[0525] For example, compared with Examples P3 and P19, the cycle performance of the positive electrode layer of Comparative Example P1, which is not provided with the sulfide solid electrolyte provided in the first aspect of the present application, is obviously deteriorated.

[0526] For example, compared with Example N3, the cycle performance of the negative electrode layer of Comparative Example N1, which is not provided with the sulfide solid electrolyte provided in the first aspect of the present application, is obviously deteriorated.

[0527] Table 3.

[0528] Table 4.

[0529] The above description of various embodiments tends to emphasize differences between various embodiments, and the same or similar parts can be referred to each other, and will not be described herein for the sake of brevity. The technical features of the above-described embodiments can be combined in any manner, and for the sake of brevity, all possible combinations of the technical features in the above-described embodiments are not described, but as long as the combinations of the technical features do not contradict, it should be considered that they are within the scope of the present specification. It should be noted that the present application is not limited to the above-described embodiments. The above-described embodiments are merely examples, and embodiments having substantially the same configuration and playing the same role and effect as the technical idea within the scope of the technical solutions of the present application are all included in the technical scope of the present application. The above-described embodiments only express several embodiments of the present application, and the description is relatively detailed, but it should not be understood as a limitation on the scope of the patent. In addition, within the scope of the main idea of the present application, various modifications that can be thought of by those skilled in the art are applied to the embodiments, and other ways constructed by combining part of the elements in the embodiments are also included in the scope of the present application.

Claims

1. A sulfide solid electrolyte comprising an LGPS-type crystal phase; The LGPS-type crystal phase includes Li element, Sn element, P element, and S element, wherein, an atomic number ratio of Sn element to S element is greater than 1 / 12, and an atomic number ratio of Sn element to P element is greater than 1 / 2; the LGPS-type crystal phase includes or does not include a cation substitution element, and includes or does not include an anion substitution element; when the LGPS-type crystal phase includes the cation substitution element, the cation substitution element includes Sb element; when the LGPS-type crystal phase includes the anion substitution element, the anion substitution element includes at least one of O element and Cl element.

2. The sulfide solid electrolyte according to claim 1, wherein the LGPS-type crystal phase satisfies one or more of the following characteristics: In the LGPS-type crystal phase, the atomic number ratio of the cation substitution element and the P element is denoted 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 number ratio of the anion substitution element and the S element is denoted 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, wherein, the LGPS-type crystal phase satisfies one or more of the following characteristics: an atomic number ratio of Sn element to S element is greater than or equal to 11 / 120; an atomic number ratio of Sn element to S element is less than or equal to 17 / 86, and optionally, greater than or equal to 14 / 120 and less than or equal to 16 / 91; an atomic number ratio of Sn element to P element is greater than or equal to 11 / 19; an atomic number ratio of Sn element to 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, wherein the LGPS-type crystal phase includes Sb element; and optionally, an 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, an atomic number ratio of Sb element to 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, an atomic number ratio of a sum of Sn element and Sb element to S element is greater than 1 / 12 and less than or equal to 21 / 86, and further optionally, greater than or equal to 11 / 120 and less than or equal to 21 / 86, and more further optionally, greater than or equal to 16 / 120 and less than or equal to 19 / 91; optionally, an atomic number ratio of a sum of Sn element and Sb element to P element is greater than 1 / 2 and less than or equal to 21 / 9, and further optionally, greater than or equal to 11 / 19 and less than or equal to 21 / 9, and more 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, wherein the LGPS-type crystal phase includes at least one of O element and Cl element; optionally, the LGPS-type crystal phase includes O element, and further optionally, an atomic number ratio of O element to S element is greater than 0 and less than or equal to 29 / 86; optionally, an atomic number ratio of O element to 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, an atomic number ratio of Cl element to S element is greater than 0 and less than or equal to 5 / 86; optionally, an atomic number ratio of Cl element to 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, wherein The LGPS-type crystal phase includes or does not include the Sb element, and further includes or does not include the O element, and further includes or does not include the Cl element; The atomic number ratio of the Li element, the Sn element, the P element, the Sb element, the S element, the O element and the Cl element is (10+x-m):(1+x):(2-x-y):y:(12-z-m):z:m; wherein 0 7. The sulfide solid electrolyte according to claim 6, wherein 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, wherein The LGPS-type crystal 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, wherein The LGPS-type crystal 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, wherein y = 0, z = 0, m = 0.

11. The sulfide solid electrolyte according to claim 6 or 7, wherein 0 < y ≤ 0.4, z = 0, m = 0.

12. The sulfide solid electrolyte according to claim 6 or 7, wherein y = 0, 0 < z ≤ 2.9, m = 0.

13. The sulfide solid electrolyte according to claim 6 or 7, wherein y = 0, z = 0, 0 < m ≤ 0.

5.

14. The sulfide solid electrolyte according to claim 1 or 2, wherein The LGPS-type crystal phase includes one or more of the following compounds represented by the following chemical formulae: 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 and 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, wherein The 2θ (°) diffraction angle in the X-ray diffraction pattern of the sulfide solid electrolyte has characteristic peaks consistent with the LGPS-type crystal phase.

16. The sulfide solid electrolyte according to claim 15, wherein 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 rays; The X-ray diffraction pattern of the sulfide solid electrolyte is obtained by powder X-ray diffraction testing.

17. A preparation method of a sulfide solid electrolyte, comprising the following steps: A precursor mixture comprising Li2S, P2S5, SnS2, and elemental sulfur is provided in the stoichiometric proportions of the desired starting materials, with or without a source of cations, with or without a source of anions; wherein, The cation source is a raw material for providing a cation substitution element, and the anion source is a raw material for providing an anion substitution element; when the sulfide solid electrolyte includes a cation substitution element, the cation substitution element includes an Sb element; when the sulfide solid electrolyte includes an anion substitution element, the anion substitution element includes at least one of an O element and a Cl element; when the sulfide solid electrolyte contains the Sb element, the precursor mixture includes Sb2S3; when the sulfide solid electrolyte contains the O element, the precursor mixture includes P2O5; when the sulfide solid electrolyte contains the Cl element, the precursor mixture includes LiCl; The cation source is a raw material for providing a cation substitution element, and the anion source is a raw material for providing an anion substitution element; when the sulfide solid electrolyte includes a cation substitution element, the cation substitution element includes an Sb element; when the sulfide solid electrolyte includes an anion substitution element, the anion substitution element includes at least one of an O element and a Cl element; when the sulfide solid electrolyte contains the Sb element, the precursor mixture includes Sb2S3; when the sulfide solid electrolyte contains the O element, the precursor mixture includes P2O5; when the sulfide solid electrolyte contains the Cl element, the precursor mixture includes LiCl; sintering the precursor mixture in an inert atmosphere to prepare a sulfide solid electrolyte comprising a LGPS-type crystal phase, wherein 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. 18.The method of claim 17, wherein the sulfide solid electrolyte satisfies one or more of the following characteristics: the weight percentage of the elemental sulfur 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 is optionally 530°C to 620°C; the prepared sulfide solid electrolyte is the sulfide solid electrolyte of any one of claims 1 to 16. 19.A solid electrolyte membrane comprising at least one of the sulfide solid electrolyte of any one of claims 1 to 16 and the sulfide solid electrolyte prepared by the method of claim 17 or 18. 20.An electrode sheet comprising an electrode active material layer, the electrode active material layer comprising an electrode active substance, and further comprising at least one of the sulfide solid electrolyte of any one of claims 1 to 16 and the sulfide solid electrolyte prepared by the method of claim 17 or 18.

21. The electrode patch of claim 20, wherein, 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 sheet is a negative electrode sheet, the electrode active material layer is referred to as a negative electrode active material layer, and the electrode active substance is referred to as a negative electrode active substance. 22.A solid-state battery comprising at least one of the sulfide solid electrolyte of any one of claims 1 to 16, the sulfide solid electrolyte prepared by the method of claim 17 or 18, the solid electrolyte membrane of claim 19, and the electrode sheet of claim 20 or 21.

23. The solid-state battery of claim 22, wherein, the solid-state battery is a sulfide all-solid-state battery. 24.An electric device comprising at least one of the sulfide solid electrolyte of any one of claims 1 to 16, the sulfide solid electrolyte prepared by the method of claim 17 or 18, the solid electrolyte membrane of claim 19, the electrode sheet of claim 20 or 21, and the solid-state battery of claim 22 or 23.

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