All-solid-state battery

Abstract

The invention relates to an all-solid-state battery, the all-solid-state battery comprises a positive electrode, a non-lithium negative electrode and a solid-state electrolyte membrane arranged between the positive electrode and the non-lithium negative electrode, and the solid-state electrolyte membrane comprises a first solid-state electrolyte. The first solid electrolyte applied to the all-solid-state battery provided by the invention can be well compatible with a positive electrode and can also react with lithium dendrites of a negative electrode, so that the cycle performance of the all-solid-state battery is effectively improved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to an all-solid-state battery. Background Art

[0002] In existing battery designs, a high operating voltage is conducive to battery performance, but traditional solid-state electrolytes are prone to decomposition or side reactions with the positive electrode under high voltage, causing the all-solid-state battery's cycle performance to deteriorate or even fail. On the negative electrode, the uneven deposition of lithium ions to form dendrites is also the main reason for the degradation of battery cycle performance.

[0003] Therefore, it is urgent to develop new all-solid-state batteries to solve the above technical problems. Summary of the Invention

[0004] Based on this, the present application provides an all-solid-state battery to solve the above technical problems.

[0005] The present application provides an all-solid-state battery, comprising a positive electrode, a non-lithium negative electrode, and a solid electrolyte membrane disposed therebetween, wherein the solid electrolyte membrane comprises a first solid electrolyte, and the first solid electrolyte comprises Li a1 P b1 S c1 O d1 Cl e1 F f1 , where a1+5b1=2c1+2d1+e1+f1, 4≤a1≤7, 0.8≤b1≤1.3, 2≤c1≤6, 0<d1≤3, 0<e1≤2, 0<f1≤2; and / or Li a2 P b2 S c2 O d2 Cl e2 , among which, a2+5b2=2c2+2d2+e2, 4≤a2≤7, 0.8≤b2≤1.3, 2≤c2≤6, 0<d2≤3, 0<e2≤4.

[0006] In some embodiments, the continuous oxidative decomposition potential U1 of the first solid electrolyte is ≥4.2V.

[0007] In some embodiments, the ionic conductivity λ1 of the first solid electrolyte is 0.5 mS / cm to 10 mS / cm.

[0008] In some embodiments, the solid electrolyte membrane has a thickness of 10 μm to 200 μm.

[0009] In some embodiments, the solid electrolyte membrane has an initial Young's modulus of 5 GPa to 40 GPa.

[0010] In some embodiments, the mass proportion of the first solid electrolyte in the solid electrolyte membrane is greater than 99%.

[0011] In some embodiments, no binder is included in the solid electrolyte membrane.

[0012] In some embodiments, the non-lithium negative electrode includes a negative electrode active material.

[0013] In some embodiments, the negative electrode active material includes at least one of a carbon material, a silicon-based material, and an oxide material.

[0014] In some embodiments, the non-lithium negative electrode further comprises a first solid-state electrolyte.

[0015] In some embodiments, the positive electrode includes a positive electrode layer, and the continuous oxidative decomposition potential U0 of the positive electrode active material in the positive electrode layer is ≥4.3V.

[0016] The present application provides a first solid electrolyte for use in an all-solid-state battery, which can achieve good compatibility with the positive electrode and react with the lithium dendrites of the negative electrode, thereby effectively improving the cycle performance of the all-solid-state battery. DETAILED DESCRIPTION

[0017] Reference will now be made to embodiments of the present application in detail, one or more examples of which are described below. Each example is provided to illustrate, but not to limit, the present application. Indeed, it will be apparent to those skilled in the art that various modifications and variations may be made to the present application without departing from the scope or spirit of the present application. For example, features illustrated or described as part of one embodiment may be used in another embodiment to produce further embodiments.

[0018] Therefore, it is intended that this application covers such modifications and variations that fall within the scope of the appended claims and their equivalents. Other objects, features, and aspects of the present application are disclosed in or are apparent from the following detailed description. Those skilled in the art will appreciate that this discussion is merely a description of exemplary embodiments and is not intended to limit the broader aspects of the present application.

[0019] In this application, the technical features described in an open manner include closed technical solutions composed of the listed features, and also include open technical solutions containing the listed features.

[0020] In this application, when referring to numerical ranges, unless otherwise specified, the numerical ranges are considered continuous and include the minimum and maximum values of the range, as well as every value between such minimum and maximum values. Further, when a range refers to an integer, every integer between the minimum and maximum values of the range is included. In addition, when multiple ranges are provided to describe a feature or characteristic, the ranges can be combined. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges subsumed therein.

[0021] In this document, when referring to a range, if the unit is followed only by the right endpoint, it means that the units of the left and right endpoints are the same. For example, 100~150 nm means that the units of the left endpoint "100" and the right endpoint "150" are both nm (nanometers).

[0022] Unless otherwise specified, all embodiments and optional embodiments of the present application can be combined with each other to form a new technical solution.

[0023] Unless otherwise specified, all technical features and optional technical features of this application can be combined with each other to form a new technical solution.

[0024] Unless otherwise specified, all steps of the present application may be performed sequentially or randomly, preferably sequentially. For example, a statement that a method includes steps (a) and (b) indicates that the method may include steps (a) and (b) performed sequentially, or may include steps (b) and (a) performed sequentially. For example, a statement that a method may also include step (c) indicates that step (c) may be added to the method in any order, for example, the method may include steps (a), (b), and (c), or may include steps (a), (c), and (b), or may include steps (c), (a), and (b), etc.

[0025] Unless otherwise specified, the terms "include" and "comprising" used in this application may be open-ended or closed-ended. For example, "include" and "comprising" may indicate that other components not listed may also be included or that only the listed components are included.

[0026] Unless otherwise specified, the term "or" is used in this application to be inclusive. For example, the phrase "A or B" means "A, B, or both A and B." More specifically, the condition "A or B" is satisfied if any of the following conditions are met: A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists); or both A and B are true (or exist).

[0027] The first aspect of the present application provides an all-solid-state battery, comprising a positive electrode, a non-lithium negative electrode, and a solid electrolyte membrane disposed therebetween, wherein the solid electrolyte membrane comprises a first solid electrolyte, and the first solid electrolyte comprises Li a1 P b1 S c1 O d1 Cl e1 F f1 , where a1+5b1=2c1+2d1+e1+f1, 4≤a1≤7, 0.8≤b1≤1.3, 2≤c1≤6, 0<d1≤3, 0<e1≤2, 0<f1≤2; and / or Li a2 P b2 S c2 O d2 Cl e2 , among which, a2+5b2=2c2+2d2+e2, 4≤a2≤7, 0.8≤b2≤1.3, 2≤c2≤6, 0<d2≤3, 0<e2≤4.

[0028] The upper limit of the operating voltage U of the all-solid-state battery satisfies: U≥4.2V.

[0029] In this application, “non-lithium negative electrode” refers to a negative electrode that does not contain lithium metal or lithium alloy.

[0030] The present application provides a first solid electrolyte for use in an all-solid-state battery, which can achieve good compatibility with the positive electrode and react with the lithium dendrites of the negative electrode, thereby effectively improving the cycle performance of the all-solid-state battery.

[0031] In some embodiments, the continuous oxidation decomposition potential U1 of the first solid electrolyte is ≥ 4.2 V. For example, the continuous oxidation decomposition potential U1 of the first solid electrolyte includes but is not limited to 4.2 V, 4.25 V, 4.3 V, 4.31 V, 4.32 V, 4.33 V, 4.35 V, and 4.36 V.

[0032] The continuous oxidation decomposition potential of the first solid electrolyte is high. When the operating voltage of the battery is high, the stability of the solid electrolyte membrane is improved, and it is not easy to have side reactions with the positive electrode or decompose, which can effectively improve the cycle performance of the all-solid-state battery.

[0033] In some embodiments, the ionic conductivity λ1 of the first solid electrolyte is 0.5 mS / cm to 10 mS / cm, including but not limited to 0.5 mS / cm, 1.5 mS / cm, 2.5 mS / cm, 3.5 mS / cm, 4.5 mS / cm, 5.5 mS / cm, 6.5 mS / cm, 7.5 mS / cm, 8.5 mS / cm, and 10 mS / cm.

[0034] The present application prepares a solid electrolyte membrane using a first solid electrolyte with high ionic conductivity, which can effectively improve the lithium ion transmission efficiency of the solid electrolyte membrane, thereby effectively enhancing the fast charging performance of the battery.

[0035] In one embodiment, the first solid electrolyte comprises Li6PS 2.5 O2ClF、Li6PS 2.5 O2Cl 1.5 F 0.5 、Li6PS 2.5 O 2.5 Cl、Li5PS 2.5 O 1.75 Cl 1.5 Any one or a combination of at least two of .

[0036] In some embodiments, the thickness of the solid electrolyte membrane is 10 μm to 200 μm, including but not limited to 10 μm, 20 μm, 40 μm, 60 μm, 80 μm, 100 μm, 120 μm, 140 μm, 150 μm, 160 μm, 180 μm, and 200 μm. Furthermore, the thickness of the solid electrolyte membrane is 30 μm to 80 μm.

[0037] When the thickness exceeds the above range, the lithium ion migration barrier increases significantly due to the extension of the path, resulting in increased resistance; when the thickness is insufficient, part of the first solid electrolyte reacts with possible lithium dendrites, and the dendrite suppression requirements cannot be met.

[0038] In some embodiments, the solid electrolyte membrane has an initial Young's modulus of 5 GPa to 40 GPa.

[0039] It is understood that the initial Young's modulus refers to the Young's modulus of the solid electrolyte membrane after preparation. The advantage of this setting is that the solid electrolyte membrane is relatively soft, which can effectively improve the contact between the positive and negative electrodes, improve the interfacial performance, and overcome the serious interfacial problems caused by the solid-solid contact between the electrode and the solid electrolyte membrane in traditional all-solid-state batteries.

[0040] This application adds a first solid electrolyte to the solid electrolyte membrane. This first solid electrolyte can react with the lithium metal deposited on the surface of the non-lithium negative electrode to generate Li2O and LiF that do not affect the transmission of lithium ions, thereby effectively preventing uneven deposition of lithium ions. At the same time, the hardness of the first solid electrolyte used in this application is less than the product generated by its reaction with lithium metal. Therefore, even if the entire contact interface between the solid electrolyte membrane and the non-lithium negative electrode reacts with lithium metal, the product layer formed can effectively inhibit the growth of lithium dendrites on the negative electrode side, pierce the solid electrolyte membrane, and prevent battery short circuits.

[0041] In some embodiments, the first solid electrolyte accounts for 99% or greater by mass of the solid electrolyte membrane. Preferably, it accounts for 99.5% or greater, and more preferably, it accounts for 99.9% or greater. A higher proportion of the first solid electrolyte by mass facilitates the construction of ion transport pathways and allows for timely reaction with lithium dendrites to prevent their continued growth.

[0042] In some embodiments, no binder is included in the solid electrolyte membrane.

[0043] In some embodiments, the solid electrolyte membrane further includes a binder.

[0044] It is understandable that the present application does not specifically limit the type of binder added to the solid electrolyte membrane. Without violating the overall inventive concept of the present application, any known type of binder that can achieve solid electrolyte membrane molding can be applied to the present application.

[0045] The following is merely an example, and the binder includes any one or a combination of at least two of polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polyvinylidene fluoride hexafluoropropylene (PVDF-HFP), polypropylene (PP), polyethylene (PE), styrene-butadiene rubber (SBR), nitrile rubber (NBR), sodium carboxymethyl cellulose (CMC), polyacrylic acid, polyacrylonitrile, and sodium alginate.

[0046] In some embodiments, the solid electrolyte membrane includes several solid electrolyte layers, and at least the solid electrolyte layer adjacent to the non-lithium negative electrode includes a first solid electrolyte.

[0047] In some embodiments, the solid electrolyte layer including the first solid electrolyte has a mass ratio of greater than 99%.

[0048] For example only, the solid electrolyte membrane may include 2, 3, or 4 solid electrolyte layers, which are not listed one by one here.

[0049] In some embodiments, the non-lithium negative electrode includes a negative electrode active material.

[0050] In some embodiments, the negative electrode active material includes at least one of a carbon material, a silicon-based material, and an oxide material.

[0051] In some embodiments, the silicon-based material includes but is not limited to any one of Si, Si-Al alloy, Si-In alloy, or a combination of at least two thereof.

[0052] In some embodiments, the carbon material includes but is not limited to any one of graphite, hard carbon, and soft carbon, or a combination of at least two thereof.

[0053] In some embodiments, the oxide material is not limited to Li4Ti5O 12 .

[0054] In some embodiments, the non-lithium negative electrode further comprises a first solid electrolyte.

[0055] The present application adds a first solid electrolyte to the non-lithium negative electrode. On the one hand, the first solid electrolyte can react with the lithium metal deposited on the surface of the non-lithium negative electrode to generate Li2O and LiF that do not affect the transmission of lithium ions, and can effectively prevent the uneven deposition of lithium ions. At the same time, it can effectively inhibit the growth of lithium dendrites on the negative electrode side, pierce the solid electrolyte membrane, and prevent the battery from short circuiting.

[0056] On the other hand, the first solid electrolyte is added to both the negative electrode and the contacting solid electrolyte membrane. The same or similar solid electrolyte components can reduce the chemical potential difference and structural differences at the interface, effectively improve the interface performance between the solid electrolyte membrane and the negative electrode, and increase the chemical compatibility and physical continuity between the negative electrode and the contacting solid electrolyte membrane.

[0057] In some embodiments, the non-lithium negative electrode further includes a negative electrode conductor, a negative electrode binder, and a negative electrode current collector.

[0058] Negative electrode conductive agents include, but are not limited to, carbon-based materials, powdered nickel or other metal particles, or conductive polymers. Carbon-based materials may include, for example, carbon black, graphite, super-P, acetylene black (such as KETCHEN™ black or DENKA™ black), carbon fibers and nanotubes, graphene, and the like. Examples of conductive polymers include polyaniline, polythiophene, polyacetylene, polypyrrole, poly(3,4-ethylenedioxythiophene) polystyrene sulfonate, and the like.

[0059] The negative electrode binder includes but is not limited to any one or a combination of at least two of polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polypropylene (PP), polyvinyl chloride (PVC), polystyrene (PS), polyoxymethylene (POM), polycarbonate (PC), polyamide (PA), acrylic plastics, other polyolefins and their copolymers, polysulfone, polyphenylene ether (PPO), styrene-butadiene rubber (SBR) and carboxymethyl cellulose (CMC).

[0060] In some embodiments, the positive electrode further includes a positive electrode layer and a positive electrode current collector, and the positive electrode layer includes a positive electrode active material, a positive electrode conductor, and a positive electrode binder.

[0061] The continuous oxidative decomposition potential U0 of the positive electrode active material in the positive electrode layer is ≥ 4.3 V. The continuous oxidative decomposition potential U0 of the positive electrode active material includes but is not limited to 4.3 V, 4.35 V, 4.4 V, 4.41 V, 4.42 V, 4.43 V, and 4.45 V.

[0062] Illustratively, the positive electrode active material includes one or more of lithium cobalt oxide, high nickel ternary positive electrode material, lithium-rich manganese-based positive electrode material, and lithium nickel manganese oxide.

[0063] The positive electrode conductive material is mainly used to assist and improve the conductivity in the battery, and there is no particular limitation on it in the embodiments of the present application, as long as it has conductivity and does not cause chemical changes. The following is only exemplary, the positive electrode conductive agent includes graphite, such as natural graphite or artificial graphite; carbon materials, such as super-P, acetylene black, Ketjen black, channel black, furnace black, lamp black and thermal black; conductive fibers, such as carbon fibers and metal fibers; conductive tubes, such as carbon nanotubes; metal powders, such as fluorocarbon powders, aluminum powders and nickel powders; conductive whiskers, such as zinc oxide and potassium titanate; conductive metal oxides, such as titanium oxide; and polyphenylene derivatives.

[0064] The positive electrode binder includes but is not limited to any one or a combination of at least two of polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polypropylene (PP), polyvinyl chloride (PVC), polystyrene (PS), polyoxymethylene (POM), polycarbonate (PC), polyamide (PA), acrylic plastics, other polyolefins and their copolymers, polysulfone, polyphenylene ether (PPO), styrene-butadiene rubber (SBR) and carboxymethyl cellulose (CMC).

[0065] In some embodiments, the positive electrode further includes a first solid electrolyte.

[0066] This application simultaneously adds a first solid electrolyte to the positive electrode, thereby improving the interface contact between the positive electrode and the solid electrolyte membrane, reducing the obstruction of ion transmission at the interface, reducing the interface resistance, and increasing the migration rate of lithium ions between the positive electrode and the solid electrolyte membrane, thereby improving the charge and discharge efficiency of the battery. At the same time, adding the first solid electrolyte to the positive electrode can fill the gaps between the positive electrode active materials, alleviate the stress caused by the volume change of the positive electrode active materials during the charge and discharge process, enhance the structural stability of the positive electrode, and improve the cycle performance of the battery.

[0067] It should be understood that the above examples of positive and negative electrodes are merely illustrative. Without violating the inventive concept of this application, any known positive electrode active material, positive electrode binder, positive electrode conductive agent, negative electrode active material, negative electrode binder, and negative electrode conductive agent may be used in this application. Furthermore, the addition of known additives based on actual usage requirements should also be considered within the scope of protection of this application.

[0068] In some embodiments, the positive electrode current collector is not particularly limited as long as it has conductivity and does not cause chemical changes in the battery. Specifically, copper, stainless steel, aluminum, nickel, titanium, or a metal current collector with a surface treated with carbon or other substances can be used.

[0069] In some embodiments, the shape of the negative electrode current collector includes any one of a foil shape, a plate shape, or a grid shape; further, the negative electrode current collector includes any one of aluminum, copper, nickel, or zinc; optionally, the negative electrode current collector is copper, such as copper foil; further, the negative electrode current collector includes any one of aluminum, copper, nickel, or zinc alloy.

[0070] A second aspect of the present application provides an electrical device, which includes the all-solid-state battery provided in the first aspect above.

[0071] It is understood that the present application does not specifically limit the method for preparing the solid electrolyte membrane. Any known process for preparing a solid electrolyte membrane can be applied to the present application without violating the inventive concept of the present application. The following is presented for illustrative purposes only.

[0072] The third aspect of the present application provides a method for preparing the solid electrolyte membrane provided in the first aspect above.

[0073] In some embodiments, the mass proportion of the first solid electrolyte in the solid electrolyte membrane is 100%, and the method for preparing the solid electrolyte membrane includes the following steps:

[0074] The first solid electrolyte is subjected to a roll pressing process to obtain a solid electrolyte membrane.

[0075] In some embodiments, the solid electrolyte membrane includes a first solid electrolyte and a binder, and the method for preparing the solid electrolyte membrane includes the following steps:

[0076] Mixing the first solid electrolyte and the binder to prepare a mixture;

[0077] The mixed material is subjected to roller pressing to obtain a solid electrolyte membrane.

[0078] In some embodiments, the solid electrolyte membrane includes two solid electrolyte layers, a second solid electrolyte layer close to the positive electrode, and a first solid electrolyte layer close to the non-lithium negative electrode, wherein the second solid electrolyte layer includes a second solid electrolyte and the first solid electrolyte layer includes a first solid electrolyte. The method for preparing the solid electrolyte membrane includes the following steps:

[0079] performing a roll-pressing process on the second solid electrolyte to obtain a second solid electrolyte layer;

[0080] performing a roll-pressing process on the first solid electrolyte to obtain a first solid electrolyte layer;

[0081] The first solid electrolyte layer and the second solid electrolyte layer are attached together and subjected to a roll pressing process to produce a solid electrolyte membrane.

[0082] In some embodiments, the Young's modulus of the second solid electrolyte layer satisfies <50 GPa.

[0083] In some embodiments, the second solid electrolyte includes one or more of Li2ZrCl6 and its derivatives, Li3InCl6 and its derivatives, Li3YCl6 and its derivatives, Li3La(PO4)2 and its derivatives, etc. It is understood that the derivatives here refer to halide solid electrolytes prepared by doping or the like.

[0084] Including but not limited to Li 2.4 Zr 0.7 Eu 0.2 Mg 0.1 Cl5F1、Li 2.07 Zr 0.83 Dy 0.12 Nb 0.05 Cl 5.8 F 0.2 、Li2ZrCl5O 0.5 、Li3InCl5Br、Li3In 0.9 Sc 0.1 Cl6、Li3YCl3Br3、Li3Y 0.8 Al 0.2 Cl6, Li3La(PO4)2, etc.

[0085] The present application will be further described below with reference to specific embodiments and comparative examples.

[0086] Example 1

[0087] Preparation of positive electrode: LiNi 0.8 Co 0.1 Mn 0.1O2 (NCM811), positive electrode binder PTFE, positive electrode conductor super-P and the first solid electrolyte Li6PS 2.5 O₂ClF₂ was uniformly mixed in a mass ratio of 70:3:2:25 and placed in a high-shear mixer for fiberization to form a first mixture. This first mixture was then roller-pressed to form a positive electrode layer at a temperature of 60°C for 5 minutes. The positive electrode layer was then laminated with the positive electrode current collector aluminum foil to produce the positive electrode.

[0088] Preparation of negative electrode: negative electrode active material graphite, negative electrode binder PTFE, negative electrode conductive agent super-P and the first solid electrolyte Li6PS 2.5 O₂ClF₂ was mixed uniformly in a mass ratio of 70:3:2:25 and placed in a high-shear mixer for fiberization to form a second mixture. This second mixture was then roller-pressed to form the negative electrode layer at a temperature of 60°C for 5 minutes. The negative electrode layer was then laminated with the negative electrode current collector copper foil to produce the negative electrode.

[0089] Preparation of solid electrolyte membrane: According to the first solid electrolyte Li6PS 2.5 O2ClF was roll-pressed at a pressure of 400 MPa to produce a solid electrolyte membrane. The membrane had an ionic conductivity of 2.75 mS / cm and a thickness of 50 μm. The continuous oxidation decomposition potential (U1) of the first solid electrolyte was 4.3 V.

[0090] Preparation of all-solid-state batteries: A positive electrode is attached to one side of a solid electrolyte membrane, and a negative electrode is attached to the other side of the solid electrolyte membrane, and the membrane is rolled under a pressure of 200 MPa to prepare an all-solid-state battery.

[0091] Example 2

[0092] The main difference between this embodiment and embodiment 1 is that in the preparation of the solid electrolyte membrane, the first solid electrolyte in the solid electrolyte membrane is Li6PS 2.5 O 2.5 Cl. The ionic conductivity of the solid electrolyte membrane is 4.86 mS / cm, and the thickness of the solid electrolyte membrane is 50 μm, as follows:

[0093] Preparation of positive electrode: LiNi 0.8 Co 0.1 Mn 0.1 O2 (NCM811), positive electrode binder PTFE, positive electrode conductor super-P and the first solid electrolyte Li6PS 2.5 O 2.5Cl was uniformly mixed in a mass ratio of 70:3:2:25 and placed in a high-shear mixer for fiberization to form a first mixture. The first mixture was then roll-pressed to form a positive electrode layer at a temperature of 60°C for 5 minutes. The positive electrode layer and the positive electrode current collector aluminum foil were then laminated together to form a positive electrode.

[0094] Preparation of negative electrode: negative electrode active material graphite, negative electrode binder PTFE, negative electrode conductive agent super-P and the first solid electrolyte Li6PS 2.5 O 2.5 Cl was mixed uniformly in a mass ratio of 70:3:2:25 and placed in a high-shear mixer for fiberization to form a second mixture. This second mixture was then roller-pressed to form a negative electrode layer at a temperature of 60°C for 5 minutes. The negative electrode layer was then laminated with a negative electrode current collector copper foil to produce a negative electrode.

[0095] Preparation of solid electrolyte membrane: According to the first solid electrolyte Li6PS 2.5 O 2.5 Cl was roller-pressed at a pressure of 400 MPa to produce a solid electrolyte membrane. The solid electrolyte membrane had an ionic conductivity of 4.86 mS / cm and a thickness of 50 μm. The continuous oxidative decomposition potential (U1) of the first solid electrolyte was 4.25 V.

[0096] Preparation of all-solid-state batteries: A positive electrode is attached to one side of a solid electrolyte membrane, and a negative electrode is attached to the other side of the solid electrolyte membrane, and the membrane is rolled under a pressure of 200 MPa to prepare an all-solid-state battery.

[0097] Example 3

[0098] The main difference between this embodiment and embodiment 1 is that in the preparation of the solid electrolyte membrane, the first solid electrolyte in the solid electrolyte membrane is Li6PS 2.5 O2Cl 1.5 F 0.5 The ionic conductivity of the solid electrolyte membrane is 3.68 mS / cm, and the thickness of the solid electrolyte membrane is 50 μm, as follows:

[0099] Preparation of positive electrode: LiNi 0.8 Co 0.1 Mn 0.1 O2 (NCM811), positive electrode binder PTFE, positive electrode conductor super-P and the first solid electrolyte Li6PS 2.5 O2Cl 1.5 F 0.5The mixture was uniformly mixed in a mass ratio of 70:3:2:25 and placed in a high-shear mixer for fiberization to form a first mixture. The first mixture was then roll-pressed to form a positive electrode layer at a temperature of 60°C for 5 minutes. The positive electrode layer and the positive electrode current collector aluminum foil were then laminated together to form a positive electrode.

[0100] Preparation of negative electrode: negative electrode active material graphite, negative electrode binder PTFE, negative electrode conductive agent super-P and the first solid electrolyte Li6PS 2.5 O2Cl 1.5 F 0.5 The mixture was uniformly mixed in a mass ratio of 70:3:2:25 and placed in a high-shear mixer for fiberization to form a second mixture. The second mixture was then roller-pressed to form the negative electrode layer at a temperature of 60°C for 5 minutes. The negative electrode layer and the negative electrode current collector copper foil were then laminated together to form the negative electrode.

[0101] Preparation of solid electrolyte membrane: According to the first solid electrolyte Li6PS 2.5 O2Cl 1.5 F 0.5 Roll-pressing was performed at a pressure of 400 MPa to produce a solid electrolyte membrane. The membrane had an ionic conductivity of 3.68 mS / cm and a thickness of 50 μm. The first solid electrolyte had a continuous oxidative decomposition potential (U1) of 4.3 V.

[0102] Preparation of all-solid-state batteries: A positive electrode is attached to one side of a solid electrolyte membrane, and a negative electrode is attached to the other side of the solid electrolyte membrane, and the membrane is rolled under a pressure of 200 MPa to prepare an all-solid-state battery.

[0103] Example 4

[0104] The main difference between this embodiment and embodiment 1 is that in the preparation of the solid electrolyte membrane, the first solid electrolyte in the solid electrolyte membrane is Li5PS 2.5 O 1.75 Cl 1.5 The ionic conductivity of the solid electrolyte membrane is 4.36 mS / cm, and the thickness of the solid electrolyte membrane is 50 μm, as follows:

[0105] Preparation of positive electrode: LiNi 0.8 Co 0.1 Mn 0.1 O2 (NCM811), positive electrode binder PTFE, positive electrode conductor super-P and the first solid electrolyte Li5PS 2.5 O 1.75 Cl 1.5The mixture was uniformly mixed in a mass ratio of 70:3:2:25 and placed in a high-shear mixer for fiberization to form a first mixture. The first mixture was then roll-pressed to form a positive electrode layer at a temperature of 60°C for 5 minutes. The positive electrode layer and the positive electrode current collector aluminum foil were then laminated together to form a positive electrode.

[0106] Preparation of negative electrode: negative electrode active material graphite, negative electrode binder PTFE, negative electrode conductive agent super-P and the first solid electrolyte Li5PS 2.5 O 1.75 Cl 1.5 The mixture was uniformly mixed in a mass ratio of 70:3:2:25 and placed in a high-shear mixer for fiberization to form a second mixture. The second mixture was then roller-pressed to form the negative electrode layer at a temperature of 60°C for 5 minutes. The negative electrode layer and the negative electrode current collector copper foil were then laminated together to form the negative electrode.

[0107] Preparation of solid electrolyte membrane: According to the first solid electrolyte Li5PS 2.5 O 1.75 Cl 1.5 The solid electrolyte membrane was produced by roller pressing at a pressure of 400 MPa. The ionic conductivity of the solid electrolyte membrane was 4.36 mS / cm, and the thickness of the solid electrolyte membrane was 50 μm. The continuous oxidation decomposition potential U1 of the first solid electrolyte was 4.2 V.

[0108] Preparation of all-solid-state batteries: A positive electrode is attached to one side of a solid electrolyte membrane, and a negative electrode is attached to the other side of the solid electrolyte membrane, and the membrane is rolled under a pressure of 200 MPa to prepare an all-solid-state battery.

[0109] Example 5

[0110] The main difference between this embodiment and embodiment 1 is that in the preparation of the solid electrolyte membrane, the solid electrolyte membrane includes two solid electrolyte layers. Specifically, the solid electrolyte membrane includes a second solid electrolyte layer close to the positive electrode and a first solid electrolyte layer close to the negative electrode. The second solid electrolyte layer includes a second solid electrolyte Li2ZrCl6, and the first solid electrolyte layer includes a first solid electrolyte Li6PS 2.5 O2ClF, the mass proportion of the first solid electrolyte in the solid electrolyte membrane is 10%, the ionic conductivity of the solid electrolyte membrane is 1.34 mS / cm, and the thickness of the solid electrolyte membrane is 50 μm; the details are as follows:

[0111] Preparation of positive electrode: LiNi 0.8 Co 0.1 Mn 0.1O2 (NCM811), positive electrode binder PTFE, positive electrode conductor super-P and the first solid electrolyte Li5PS 2.5 O 1.75 Cl 1.5 The mixture was uniformly mixed in a mass ratio of 70:3:2:25 and placed in a high-shear mixer for fiberization to form a first mixture. The first mixture was then roll-pressed to form a positive electrode layer at a temperature of 60°C for 5 minutes. The positive electrode layer and the positive electrode current collector aluminum foil were then laminated together to form a positive electrode.

[0112] Preparation of negative electrode: negative electrode active material graphite, negative electrode binder PTFE, negative electrode conductive agent super-P and the first solid electrolyte Li5PS 2.5 O 1.75 Cl 1.5 The mixture was uniformly mixed in a mass ratio of 70:3:2:25 and placed in a high-shear mixer for fiberization to form a second mixture. The second mixture was then roller-pressed to form the negative electrode layer at a temperature of 60°C for 5 minutes. The negative electrode layer and the negative electrode current collector copper foil were then laminated together to form the negative electrode.

[0113] Preparation of solid electrolyte membrane:

[0114] Preparation of the second solid electrolyte layer: The second solid electrolyte Li2ZrCl6 was subjected to a roller pressing process at a pressure of 400 MPa to prepare the second solid electrolyte layer.

[0115] Preparation of the first solid electrolyte layer: The first solid electrolyte Li6PS 2.5 O2ClF was roll-pressed at a pressure of 400 MPa to produce a first solid electrolyte layer, wherein the first solid electrolyte had a continuous oxidation decomposition potential U1 of 4.3 V.

[0116] Preparation of solid electrolyte membrane: The first solid electrolyte layer and the second solid electrolyte layer are laid together and subjected to roller pressing to prepare a solid electrolyte membrane.

[0117] The ionic conductivity of the solid electrolyte membrane is 1.34 mS / cm, and the thickness of the solid electrolyte membrane is 50 μm.

[0118] Preparation of all-solid-state batteries: A positive electrode is attached to one side of a solid electrolyte membrane, and a negative electrode is attached to the other side of the solid electrolyte membrane, and the membrane is rolled under a pressure of 200 MPa to prepare an all-solid-state battery.

[0119] Example 6

[0120] The main difference between this embodiment and embodiment 1 is that the thickness of the solid electrolyte membrane is 10 μm; specifically:

[0121] Preparation of positive electrode: LiNi 0.8 Co 0.1 Mn 0.1 O2 (NCM811), positive electrode binder PTFE, positive electrode conductor super-P and the first solid electrolyte Li6PS 2.5 O₂ClF₂ was uniformly mixed in a mass ratio of 70:3:2:25 and placed in a high-shear mixer for fiberization to form a first mixture. This first mixture was then roller-pressed to form a positive electrode layer at a temperature of 60°C for 5 minutes. The positive electrode layer was then laminated with the positive electrode current collector aluminum foil to produce the positive electrode.

[0122] Preparation of negative electrode: negative electrode active material graphite, negative electrode binder PTFE, negative electrode conductive agent super-P and the first solid electrolyte Li6PS 2.5 O₂ClF₂ was mixed uniformly in a mass ratio of 70:3:2:25 and placed in a high-shear mixer for fiberization to form a second mixture. This second mixture was then roller-pressed to form the negative electrode layer at a temperature of 60°C for 5 minutes. The negative electrode layer was then laminated with the negative electrode current collector copper foil to produce the negative electrode.

[0123] Preparation of solid electrolyte membrane: According to the first solid electrolyte Li6PS 2.5 O2ClF was roll-pressed at a pressure of 400 MPa to produce a solid electrolyte membrane. The membrane had an ionic conductivity of 2.75 mS / cm and a thickness of 10 μm. The continuous oxidation decomposition potential (U1) of the first solid electrolyte was 4.3 V.

[0124] Preparation of all-solid-state batteries: A positive electrode is attached to one side of a solid electrolyte membrane, and a negative electrode is attached to the other side of the solid electrolyte membrane, and the membrane is rolled under a pressure of 200 MPa to prepare an all-solid-state battery.

[0125] Example 7

[0126] This embodiment differs from embodiment 1 in that the thickness of the solid electrolyte membrane is 200 μm;

[0127] Preparation of positive electrode: LiNi 0.8 Co 0.1 Mn 0.1 O2 (NCM811), positive electrode binder PTFE, positive electrode conductor super-P and the first solid electrolyte Li6PS 2.5O₂ClF₂ was uniformly mixed in a mass ratio of 70:3:2:25 and placed in a high-shear mixer for fiberization to form a first mixture. This first mixture was then roller-pressed to form a positive electrode layer at a temperature of 60°C for 5 minutes. The positive electrode layer was then laminated with the positive electrode current collector aluminum foil to produce the positive electrode.

[0128] Preparation of negative electrode: negative electrode active material graphite, negative electrode binder PTFE, negative electrode conductive agent super-P and the first solid electrolyte Li6PS 2.5 O₂ClF₂ was mixed uniformly in a mass ratio of 70:3:2:25 and placed in a high-shear mixer for fiberization to form a second mixture. This second mixture was then roller-pressed to form the negative electrode layer at a temperature of 60°C for 5 minutes. The negative electrode layer was then laminated with the negative electrode current collector copper foil to produce the negative electrode.

[0129] Preparation of solid electrolyte membrane: According to the first solid electrolyte Li6PS 2.5 O2ClF was roll-pressed at a pressure of 400 MPa to produce a solid electrolyte membrane. The ionic conductivity of the solid electrolyte membrane was 2.75 mS / cm, and the thickness of the solid electrolyte membrane was 200 μm. The continuous oxidation decomposition potential U1 of the first solid electrolyte was 4.3 V.

[0130] Preparation of all-solid-state batteries: A positive electrode is attached to one side of a solid electrolyte membrane, and a negative electrode is attached to the other side of the solid electrolyte membrane, and the membrane is rolled under a pressure of 200 MPa to prepare an all-solid-state battery.

[0131] Example 8

[0132] This embodiment differs from Example 1 primarily in that a binder, PVDF, is added to the solid electrolyte membrane during its preparation. The mass ratio of the first solid electrolyte to the binder is 99.9:0.1. The solid electrolyte membrane has an ionic conductivity of 2.7 mS / cm and a thickness of 50 μm.

[0133] Comparative Example 1

[0134] The main difference between this comparative example and Example 1 is that in the preparation of the solid electrolyte membrane, the solid electrolyte in the solid electrolyte membrane is Li6PS5Cl. The ionic conductivity of the solid electrolyte membrane is 4.22 mS / cm, and the thickness of the solid electrolyte membrane is 50 μm.

[0135] Preparation of positive electrode: LiNi 0.8 Co 0.1 Mn 0.1O2 (NCM811), positive electrode binder PTFE, positive electrode conductive agent super-P, and the first solid electrolyte Li6PS5Cl were uniformly mixed in a mass ratio of 70:3:2:25. The mixture was placed in a high-shear mixer and subjected to fiberization to form a first mixture. The first mixture was then roll-pressed to form a positive electrode layer at a temperature of 60°C for 5 minutes. The positive electrode layer and positive electrode current collector aluminum foil were then laminated together to produce the positive electrode.

[0136] Negative electrode preparation: Graphite, the negative electrode active material, PTFE, the negative electrode binder, super-P, and the first solid electrolyte, Li6PS5Cl, were mixed uniformly in a mass ratio of 70:3:2:25. The mixture was placed in a high-shear mixer and subjected to fiberization to form a secondary mixture. This secondary mixture was then roller-pressed to form the negative electrode layer at a temperature of 60°C for 5 minutes. The negative electrode layer was then laminated with the negative electrode current collector copper foil to form the negative electrode.

[0137] Preparation of the solid electrolyte membrane: The first solid electrolyte, Li6PS5Cl, was rolled at a pressure of 400 MPa to produce a solid electrolyte membrane. The ionic conductivity of the solid electrolyte membrane was 4.22 mS / cm, and the thickness of the solid electrolyte membrane was 50 μm.

[0138] Preparation of all-solid-state batteries: A positive electrode is attached to one side of a solid electrolyte membrane, and a negative electrode is attached to the other side of the solid electrolyte membrane, and the membrane is rolled under a pressure of 200 MPa to prepare an all-solid-state battery.

[0139] Comparative Example 2

[0140] The main difference between this comparative example and Example 1 is that in the preparation of the solid electrolyte membrane, the solid electrolyte in the solid electrolyte membrane is Li2ZrCl6. The ionic conductivity of the solid electrolyte membrane is 0.73 mS / cm, and the thickness of the solid electrolyte membrane is 50 μm.

[0141] Preparation of positive electrode: LiNi 0.8 Co 0.1 Mn 0.1 O2 (NCM811), positive electrode binder PTFE, positive electrode conductive agent super-P, and the first solid electrolyte Li2ZrCl6 were uniformly mixed in a mass ratio of 70:3:2:25. The mixture was placed in a high-shear mixer and subjected to fiberization to form a first mixture. The first mixture was then roll-pressed to form a positive electrode layer at a temperature of 60°C for 5 minutes. The positive electrode layer and positive electrode current collector aluminum foil were then laminated together to produce the positive electrode.

[0142] Negative electrode preparation: Graphite, the negative electrode active material, PTFE, the negative electrode binder, super-P, and the first solid electrolyte, Li₂ZrCl₂, were mixed uniformly in a mass ratio of 70:3:2:25. The mixture was placed in a high-shear mixer and subjected to fiberization to form a secondary mixture. This secondary mixture was then roller-pressed to form the negative electrode layer at a temperature of 60°C for 5 minutes. The negative electrode layer was then laminated with the negative electrode current collector copper foil to form the negative electrode.

[0143] Preparation of the solid electrolyte membrane: The first solid electrolyte, Li₂ZrCl₂, was roll-pressed at a pressure of 400 MPa to produce a solid electrolyte membrane. The ionic conductivity of the solid electrolyte membrane was 2.75 mS / cm, and the thickness of the solid electrolyte membrane was 50 μm.

[0144] Preparation of all-solid-state batteries: A positive electrode is attached to one side of a solid electrolyte membrane, and a negative electrode is attached to the other side of the solid electrolyte membrane, and the membrane is rolled under a pressure of 200 MPa to prepare an all-solid-state battery.

[0145] Comparative Example 3

[0146] The difference between this comparative example and Example 5 is that, in the preparation of the all-solid-state battery, the first solid electrolyte is arranged close to the negative electrode, and the second solid electrolyte layer is arranged close to the positive electrode.

[0147] Test Case

[0148] The electric cycle retention rate test (500 cycles) and capacity retention rate test (2C) of the all-solid-state batteries prepared in the examples and comparative examples are as follows:

[0149] (1) Cycle retention rate test:

[0150] At room temperature, charge at a current of 0.1C to a charge cut-off voltage of 4.2V, then switch to constant voltage charging to a cut-off current of 0.05C, let it stand for 0.5h, then discharge at a current of 0.1C to a cut-off voltage of 3.0V, let it stand for 0.5h, and enter the next charge and discharge cycle, and so on, for a total of 500 charge and discharge cycles.

[0151] (2) Capacity retention test:

[0152] At a temperature of 25°C, a fully charged battery is discharged at a current of 0.1C to a cut-off voltage of 3.0V. The capacity obtained by the test is C0;

[0153] At a temperature of 25°C, a fully charged battery is discharged at a current of 2C to a cut-off voltage of 3.0V. The capacity obtained by the test is C1. C1 / C0 is the 2C discharge capacity retention rate below.

[0154] The test parameters of the embodiments and comparative examples are summarized in Table 1 below:

[0155] Table 1

[0156] Cycle retention rate (%) Capacity retention rate (%) Example 1 89 78 Example 2 82 85 Example 3 88 81 Example 4 83 83 Example 5 77 62 Example 6 87 84 Example 7 86 72 Example 8 85 76 Comparative Example 1 45 42 Comparative Example 2 17 34 Comparative Example 3 19 75

[0157] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0158] The above embodiments merely illustrate several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, all of which fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. An all-solid-state battery, characterized in that: The invention comprises a positive electrode, a non-lithium negative electrode and a solid electrolyte membrane disposed therebetween, wherein the solid electrolyte membrane comprises a first solid electrolyte, and the first solid electrolyte comprises Li a1 P b1 S c1 O d1 Cl e1 F f1 , where a1+5b1=2c1+2d1+e1+f1, 4≤a1≤7, 0.8≤b1≤1.3, 2≤c1≤6, 0<d1≤3, 0<e1≤2, 0<f1≤2; and / or Li a2 P b2 S c2 O d2 Cl e2 , among which, a2+5b2=2c2+2d2+e2, 4≤a2≤7, 0.8≤b2≤1.3, 2≤c2≤6, 0<d2≤3, 0<e2≤4.

2. The all-solid-state battery according to claim 1, characterized in that The continuous oxidation decomposition potential U1 of the first solid electrolyte is ≥4.2V.

3. The all-solid-state battery according to claim 1, characterized in that The ionic conductivity λ1 of the first solid electrolyte is 0.5 mS / cm to 10 mS / cm.

4. The all-solid-state battery according to claim 1, characterized in that The thickness of the solid electrolyte membrane is 10 μm to 200 μm.

5. The all-solid-state battery according to claim 1, characterized in that The initial Young's modulus of the solid electrolyte membrane is 5 GPa to 40 GPa.

6. The all-solid-state battery according to claim 1, characterized in that In the solid electrolyte membrane, the mass proportion of the first solid electrolyte is greater than 99%.

7. The all-solid-state battery according to claim 1, characterized in that The solid electrolyte membrane does not include a binder.

8. The all-solid-state battery according to claim 1, characterized in that The non-lithium negative electrode includes a negative electrode active material; The negative electrode active material includes at least one of a carbon material, a silicon-based material, and an oxide material.

9. The all-solid-state battery according to claim 1, characterized in that The non-lithium negative electrode also includes the first solid electrolyte.

10. The all-solid-state battery according to claim 1, characterized in that: The positive electrode includes a positive electrode layer, and a positive electrode active material in the positive electrode layer has a continuous oxidation decomposition potential U0 of ≥4.3V.