Battery assembly, preparation method thereof and battery

Abstract

The invention relates to the field of solid-state batteries, in particular to a battery assembly and a preparation method thereof and a battery, the battery assembly comprises a current collector, a negative active layer, a solid electrolyte layer, an insulating frame and a positive active layer; the negative electrode active layer is arranged on at least one surface of the current collector in the thickness direction, the solid electrolyte layer is arranged on the surface, far away from the current collector, of the negative electrode active layer, and the insulating frame is arranged on the edge of the surface, far away from the negative electrode active layer, of the solid electrolyte layer; wherein the outer edge of the insulating frame is as large as the periphery of the solid electrolyte layer; the positive electrode active layer is arranged in an internal frame area of the insulating frame; the insulating frame is made of kaolin particles. The battery assembly can effectively prevent the short circuit phenomenon caused by the step problem of the solid-state battery and effectively prevent the cracking phenomenon of the insulating frame in the working process of the battery.

Description

Technical Field

[0001] This invention relates to the field of solid-state batteries, specifically to a battery assembly, its fabrication method, and the battery itself. Background Technology

[0002] Traditional lithium-ion batteries face increasing safety concerns, with volatile, flammable, and explosive organic electrolytes being a major contributing factor. Solid-state batteries, as the next generation of lithium-ion battery technology, inherit the advantages of traditional lithium-ion batteries while offering significant advantages such as superior safety and high energy density.

[0003] However, due to the size difference between the electrolyte layer and the positive and negative electrode layers, the size mismatch of the electrode sheets during high-pressure pressing can easily lead to shear forces exerted on the electrolyte layer by the edge of the positive electrode sheet. This shear force may cause the edge of the positive electrode sheet to pierce the electrolyte layer, thus contacting the negative electrode layer and triggering a battery short circuit. To solve this problem, existing technologies use insulating rings to prevent short circuits between the positive and negative electrodes, for example, using PP / PA materials. However, while the introduction of these insulating rings isolates the positive and negative electrodes to some extent, it also leads to reduced energy density and decreased pressure resistance. To improve the energy density of the cell, some existing technologies have attempted to replace the material of the anti-short-circuit ring with a sulfide solid electrolyte. Although this material has a certain degree of ionic conductivity, the problem of lithium dendrite piercing and short-circuiting still exists due to the gap between the insulating ring and the positive electrode sheet, especially under high load conditions, the traditional negative electrode-encased positive electrode structure still faces the risk of short circuit. In addition, if non-isostatic or confined flat pressure pressing methods are used, such as rolling, the electrode sheets are prone to deformation, making it difficult to manufacture the insulating ring. Therefore, there is an urgent need in this field to develop a new short-circuit prevention method to address the challenges encountered by all-solid-state batteries in practical applications. This method should not only provide physical insulation but also suppress lithium dendrite formation to a certain extent, thereby significantly reducing the risk of battery short circuits. This will help improve the safety and reliability of all-solid-state batteries and promote their widespread application in the new energy field. Summary of the Invention

[0004] In view of this, the present invention aims to provide a battery component, a method for manufacturing the same, and a battery, to solve the short circuit problem caused by the mismatch of electrode sizes during the isostatic pressing process of solid-state batteries in the prior art, and the problem that the volume expansion of the silicon anode during cycling can lead to the cracking of the insulating frame.

[0005] To solve the above-mentioned technical problems, the present invention is implemented as follows:

[0006] A first aspect of the present invention provides a battery assembly, the battery assembly comprising a current collector, a negative electrode active layer, a solid electrolyte layer, an insulating frame, and a positive electrode active layer;

[0007] The negative electrode active layer is disposed on at least one surface of the current collector along the thickness direction, the solid electrolyte layer is disposed on the surface of the negative electrode active layer away from the current collector, and the insulating frame is disposed on the edge of the solid electrolyte layer away from the negative electrode active layer.

[0008] Wherein, the outer edge of the insulating frame is the same size as the periphery of the solid electrolyte layer; the positive electrode active layer is disposed within the inner frame area of ​​the insulating frame;

[0009] The insulating frame is made of kaolin particles.

[0010] Optionally, the width of the insulating frame is 1 to 5 mm; and / or, the thickness of the insulating frame is 30 to 200 μm; and / or, the thickness of the positive electrode active layer is equal to the thickness of the insulating frame.

[0011] Optionally, the D50 of the kaolin particles is 0.1 to 100 μm; and / or, based on the total mass of the insulating frame, the content of the kaolin particles is 50 to 99.9 wt%.

[0012] Optionally, the insulating frame material further includes an adhesive that coats the surface of the kaolin particles; the adhesive content is 0.1 to 50 wt% based on the total mass of the insulating frame.

[0013] Optionally, the adhesive includes at least one of styrene-butadiene emulsion, polystyrene copolymer, nitrile rubber, hydrogenated nitrile rubber, and polyvinylidene fluoride.

[0014] Optionally, the current collector includes at least one of carbon-coated copper foil, screen-printed copper foil, porous copper foil, and copper mesh.

[0015] A second aspect of the present invention provides a method for manufacturing a battery assembly, the method comprising the following steps:

[0016] S1. Mix kaolin, binder and solvent to obtain a mixed slurry;

[0017] S2. A negative electrode active material is disposed on at least one surface of the current collector along the thickness direction to obtain a first component; a solid electrolyte material is disposed on the surface of the first component to obtain a second component;

[0018] S3. The mixed slurry is coated onto the peripheral area of ​​the surface of the second component and dried to obtain a third component with an insulating frame.

[0019] S4. The positive electrode active layer is transferred to the inner border area of ​​the insulating frame of the third component.

[0020] Optionally, the solvent includes at least one selected from toluene, xylene, isobutyl isobutyrate, ethyl acetate, hexyl acetate, butyl butyrate, benzyl butyrate, dichloroethane, and heptane.

[0021] Optionally, in step S1, the mixing conditions include a rotation speed of 400–3000 rpm and a mixing time of 1–10 min; and / or, in step S3, the drying conditions include a temperature of 25–100°C and a time of 1–24 h.

[0022] A third aspect of the present invention provides an all-solid-state battery, the all-solid-state battery comprising a battery module, the battery module being the battery module described above or a battery module prepared according to the method described above.

[0023] The beneficial technical effects of the present invention through the above technical solution are as follows:

[0024] (1) The battery assembly of the present invention has an insulating frame on the surface of the solid electrolyte layer. The insulating frame, which is rich in kaolin material, has the characteristics of being soft, having good plasticity and high adhesion, and excellent electrical insulation performance. It can effectively prevent short circuits caused by step problems in solid batteries and effectively prevent cracking of the insulating frame during battery operation.

[0025] (2) In the battery assembly of the present invention, the size of the positive electrode active layer is smaller than that of the negative electrode active layer, and its orthogonal projection is located within the negative electrode active layer. An insulating frame based on kaolin is provided around the perimeter to compensate for the size difference, effectively improving the structural stability and safety of the battery. The solid-state battery of the present invention not only enhances the physical insulation performance of the cell and prevents the risk of short circuit, but also, the kaolin-based negative electrode frame helps to suppress lithium dendrite growth, enhance mechanical strength, improve thermal management, and extend battery life, thereby achieving an increase in battery energy density and comprehensive optimization of performance.

[0026] Other features and advantages of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0027] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the following detailed description to explain the invention, but do not constitute a limitation thereof.

[0028] Figure 1 The diagram shown is a schematic of the battery assembly of the present invention.

[0029] Figure 2 The diagram shows the positional relationship between the positive electrode active layer and the insulating frame of the battery assembly of the present invention. Detailed Implementation

[0030] This invention discloses a battery component, its fabrication method, and the battery itself. Those skilled in the art can refer to this document and appropriately modify the process parameters to achieve the desired result. It is particularly important to note that all similar substitutions and modifications are obvious to those skilled in the art and are considered to be included in this invention. The methods and applications of this invention have been described through preferred embodiments. Those skilled in the art can clearly modify or appropriately change and combine the methods and applications described herein without departing from the content, spirit, and scope of this invention to realize and apply the technology of this invention.

[0031] In the description of this invention, the list of items connected by the term "at least one of" or other similar terms may mean any combination of the listed items. For example, if items A and B are listed, then the phrase "at least one of A and B" means only A; only B; or A and B. In another example, if items A, B, and C are listed, then the phrase "at least one of A, B, and C" means only A; or only B; only C; A and B (excluding C); A and C (excluding B); B and C (excluding A); or all of A, B, and C. Item A may contain a single element or multiple elements. Item B may contain a single element or multiple elements. Item C may contain a single element or multiple elements.

[0032] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges or individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0033] Unless otherwise specified, all embodiments and optional embodiments of the present invention can be combined with each other to form new technical solutions.

[0034] Unless otherwise specified, all technical features and optional technical features of this invention can be combined to form new technical solutions.

[0035] Unless otherwise specified, the terms "comprising" and "including" as used in this invention can be open-ended or closed-ended. For example, "comprising" and "including" can mean that other components not listed may also be included, or that only the listed components may be included.

[0036] To address the short-circuit problem caused by electrode size mismatch during isostatic pressing in existing solid-state batteries, and the problem that the volume expansion of the silicon anode during cycling can lead to the breakage of the insulating frame, this invention adopts the following technical solution:

[0037] A first aspect of the present invention provides a battery assembly, such as Figure 1 As shown, the battery assembly includes a current collector, a negative electrode active layer, a solid electrolyte layer, an insulating frame, and a positive electrode active layer;

[0038] The negative electrode active layer is disposed on at least one surface of the current collector along the thickness direction, the solid electrolyte layer is disposed on the surface of the negative electrode active layer away from the current collector, and the insulating frame is disposed on the edge of the solid electrolyte layer away from the negative electrode active layer.

[0039] Wherein, the outer edge of the insulating frame is the same size as the periphery of the solid electrolyte layer; such as Figure 2 As shown, the positive electrode active layer is disposed within the inner border area of ​​the insulating frame;

[0040] The insulating frame is made of kaolin particles.

[0041] The battery assembly of this invention features an insulating frame on the surface of the solid electrolyte layer. This insulating frame, rich in kaolin, is soft, malleable, has high adhesion, and excellent electrical insulation properties. It effectively prevents short circuits caused by step-like structures in solid-state batteries and prevents cracking of the insulating frame during battery operation. The positive electrode active layer is located within the inner frame region of the insulating frame. In this battery assembly, the positive electrode active layer is smaller than the negative electrode active layer, and its orthogonal projection lies within the negative electrode active layer. The kaolin-based insulating frame around the positive electrode compensates for the size difference, effectively improving the structural stability and safety of the battery.

[0042] According to the present invention, the width of the insulating frame can be 1 to 5 mm. In this invention, if the frame width of the insulating frame is too large, it may lead to a decrease in energy density; if the frame width of the insulating frame is too small, it may lead to a short circuit in the battery cell. As a preferred embodiment of the present invention, the frame width of the insulating frame can be 1.5 to 3 mm.

[0043] According to the present invention, the thickness of the insulating frame can be 30 to 200 μm. Exemplarily, the thickness of the insulating frame can be any value among 30 μm, 50 μm, 100 μm, 120 μm, 150 μm, 180 μm and 200 μm or any value within the range of any two of the above values.

[0044] In one embodiment of the present invention, the thickness of the positive electrode active layer is equal to the thickness of the insulating frame.

[0045] According to the present invention, the D50 of the kaolin particles is 0.1 to 100 μm. Exemplarily, the D50 of the kaolin particles can be any value selected from 0.1 μm, 1 μm, 10 μm, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, and 100 μm, or any value within the range formed by any pair of the above values.

[0046] According to the present invention, the content of kaolin particles is 50 to 99.9 wt%, based on the total mass of the insulating frame. Exemplarily, the content of kaolin particles can be any value among 50 wt%, 60 wt%, 70 wt%, 80 wt%, and 99.9 wt%, or any value within the range of any pair of the above values, based on the total mass of the insulating frame.

[0047] According to the present invention, the material of the insulating frame may further include an adhesive, which coats the surface of the kaolin particles; the content of the adhesive, based on the total mass of the insulating frame, may be 0.1–50 wt%. Exemplarily, based on the total mass of the insulating frame, the content of the adhesive may be any value selected from 0.1 wt%, 1 wt%, 10 wt%, 20 wt%, 30 wt%, 40 wt%, and 50 wt%, or any value within the range of any pair of values ​​mentioned above. In the present invention, if the adhesive content is too high, the frame may be prone to deformation; if the adhesive content is too low, the frame material may be prone to cracking. As a preferred embodiment of the present invention, the content of the adhesive, based on the total mass of the insulating frame, may be 5–20 wt%.

[0048] For example, the adhesive may include at least one of styrene-butadiene latex (SBR), polystyrene copolymer (SEBS), nitrile butadiene rubber (NBR), hydrogenated nitrile butadiene rubber (HNBR), and polyvinylidene fluoride (PVDF).

[0049] This invention does not impose any particular limitation on the material of the negative electrode current collector, as long as it can achieve the purpose of this invention, it can be selected according to actual needs. For example, in some embodiments, the current collector includes common copper foil (the copper foil can be modified, such as by adding a carbon coating layer, screen-printed copper foil, porous copper foil, copper mesh, etc.), or the current collector can adopt a composite current collector structure (such as a composite current collector structure containing a polymer layer and a metal layer). Those skilled in the art can make adaptive selections according to actual needs. Preferably, the current collector in this invention may include carbon-coated copper foil.

[0050] In embodiments of the present invention, the negative electrode active layer includes a negative electrode active material, which can be a carbon material and / or a silicon-carbon negative electrode material. For example, the carbon material can be conventional negative electrode materials such as artificial graphite, natural graphite, soft carbon, and hard carbon. Optionally, the mass percentage of the negative electrode active material in the negative electrode active layer is 70%–85%. In some embodiments, the negative electrode active layer also includes a conductive agent and a binder. The present invention does not impose any particular limitation on the type of conductive agent, and conventional technologies can be used. For example, the conductive agent includes, but is not limited to, one or more combinations of superconducting carbon, conductive graphite, conductive carbon black (including acetylene black, Ketjen black, etc.), carbon nanotubes (including single-walled carbon nanotubes and / or multi-walled carbon nanotubes), graphene, or carbon fiber. Optionally, the mass percentage of the conductive agent in the negative electrode active layer is 0.5%–15%, and more specifically, 0.5%–5%. This invention does not impose any particular limitation on the type of conductive agent, and conventional technologies can also be used. For example, the binder includes, but is not limited to, one or more combinations of sodium carboxymethyl cellulose, styrene-butadiene rubber, polyacrylic acid, and polyvinylidene fluoride. Optionally, the binder accounts for 0.5% to 15% of the mass of the negative electrode active layer, and more specifically, 0.5% to 5%.

[0051] In embodiments of the present invention, the solid electrolyte layer includes a solid electrolyte material. For example, the solid electrolyte material can be a conventional solid electrolyte material such as a sulfide solid electrolyte, a halide solid electrolyte, or a halide oxide solid electrolyte. Optionally, the solid electrolyte material accounts for 95% to 99% of the mass percentage in the solid electrolyte layer.

[0052] A second aspect of the present invention provides a method for manufacturing a battery assembly, the method comprising the following steps:

[0053] S1. Mix kaolin, binder and solvent to obtain a mixed slurry;

[0054] S2. A negative electrode active material is disposed on at least one surface of the current collector along the thickness direction to obtain a first component; a solid electrolyte material is disposed on the surface of the first component to obtain a second component;

[0055] S3. The mixed slurry is coated onto the peripheral area of ​​the surface of the second component and dried to obtain a third component with an insulating frame.

[0056] S4. The positive electrode active layer is transferred to the inner border area of ​​the insulating frame of the third component.

[0057] For example, the solvent may include at least one of toluene, xylene, isobutyl isobutyrate, ethyl acetate, hexyl acetate, butyl butyrate, benzyl butyrate, dichloroethane, and heptane.

[0058] According to the present invention, in step S1, the conditions for the mixing process may include: a rotation speed of 400 to 3000 rpm and a mixing time of 1 to 10 min; as an example, the rotation speed for the mixing process may be 400 rpm, 600 rpm, 1000 rpm, 1400 rpm, 2000 rpm, etc., and the mixing time may be 1 min, 4 min, 6 min, 10 min, etc.

[0059] According to the present invention, in step S3, the drying conditions may include a temperature of 25–100°C and a time of 1–24 h. As an example, the drying temperature may be 25°C, 45°C, 60°C, 80°C, 100°C, etc., and the drying time may be 1 h, 5 h, 8 h, 15 h, 24 h, etc.

[0060] A third aspect of the present invention provides an all-solid-state battery, the all-solid-state battery comprising a battery module, the battery module being the battery module described above or a battery module prepared according to the method described above.

[0061] The solid-state battery of this invention not only enhances the physical insulation performance of the cell and prevents short-circuit risks, but also, the kaolin-based negative electrode frame helps suppress lithium dendrite growth, enhances mechanical strength, improves thermal management, and extends battery life, thereby achieving an increase in battery energy density and comprehensive performance optimization.

[0062] The present invention will be further described in detail below through examples. All raw materials used in the examples are commercially available. The kaolin particles used in the examples of the present invention have a D50 of 0.5 μm.

[0063] Example 1

[0064] Kaolin particles and polystyrene copolymer were weighed and added to p-xylene solvent at a mass ratio of 99.9%:0.1% to obtain kaolin slurry. The mixing conditions included a rotation speed of 1400 rpm and a mixing time of 1 min.

[0065] A first component is obtained by depositing a negative electrode active material on at least one surface of a current collector along its thickness direction; a second component is obtained by depositing a solid electrolyte material on the surface of the first component. In this embodiment, the negative electrode active material includes a silicon-carbon negative electrode material, a sulfide solid electrolyte, a conductive agent, and a binder mixed in a mass ratio of 70:25:3:2. The solid electrolyte material includes a sulfide-germanium ore solid electrolyte. Specifically, the silicon-carbon negative electrode material used in this embodiment is a novel silicon-carbon material, the conductive agent is conductive carbon black, the binder is sodium carboxymethyl cellulose, and the solid electrolyte material used is a sulfide-germanium ore solid electrolyte with the specific chemical formula LPSC(Li6PS5Cl).

[0066] Kaolin slurry is evenly coated onto the periphery of the second component surface using screen printing, and then dried in an oven to obtain a third component with an insulating frame. The drying conditions include: a temperature of 60°C, a time of 5 minutes, a frame width of 2 mm for the insulating frame, and an inner frame length of 60 mm and a width of 80 mm at the frame.

[0067] A positive electrode active layer with a size of 43*56mm is placed inside an insulating frame and combined with a third component that is also provided with an insulating frame to obtain the battery assembly of this embodiment.

[0068] The battery assembly of this embodiment is stacked in a positive-negative-negative-positive manner, with a stacking method of double-sided negative electrode and single-sided positive electrode, to obtain the all-solid-state battery of this embodiment.

[0069] Example 2

[0070] The solid-state battery preparation method in this embodiment is the same as in Embodiment 1, except that the mass ratio of kaolin particles to polystyrene copolymer is 99%:1%.

[0071] Example 3

[0072] The solid-state battery preparation method in this embodiment is the same as in Embodiment 1, except that the mass ratio of kaolin particles to polystyrene copolymer is 98%:2%.

[0073] Example 4

[0074] The solid-state battery preparation method in this embodiment is the same as in Embodiment 1, except that the mass ratio of kaolin particles to polystyrene copolymer is 95%:5%.

[0075] Example 5

[0076] The preparation method of the solid-state battery in this embodiment is the same as that in Embodiment 1, except that the mass ratio of kaolin particles to polystyrene copolymer is 90%:10%.

[0077] Example 6

[0078] The preparation method of the solid-state battery in this embodiment is the same as that in Embodiment 1, except that the mass ratio of kaolin particles to polystyrene copolymer is 80%:20%.

[0079] Example 7

[0080] The solid-state battery preparation method in this embodiment is the same as in Embodiment 1, except that the mass ratio of kaolin particles to polystyrene copolymer is 50%:50%.

[0081] Example 8

[0082] The solid-state battery preparation method in this embodiment is the same as in Embodiment 1, except that the width of the insulating frame is 1 mm.

[0083] Example 9

[0084] The solid-state battery preparation method in this embodiment is the same as in Embodiment 1, except that the width of the insulating frame is 3mm.

[0085] Example 10

[0086] The solid-state battery preparation method in this embodiment is the same as in Embodiment 1, except that the width of the insulating frame is 5mm.

[0087] Comparative Example 1

[0088] The preparation method of the solid-state battery in this comparative example is generally the same as that in Example 5, except that the kaolin particles are replaced with sulfide electrolyte particles. The specific chemical formula of the sulfide electrolyte particles is: Li6PS5Cl. 1.5 .

[0089] Comparative Example 2

[0090] The preparation method of the solid-state battery in this comparative example is the same as that in Example 5, except that the kaolin particles are replaced with boehmite particles, and the D50 of the boehmite particles is 0.5 μm.

[0091] Comparative Example 3

[0092] The preparation method of the solid-state battery in this comparative example is the same as that in Example 5, except that the kaolin particles are replaced with alumina powder.

[0093] Test Example 1

[0094] The solid-state batteries prepared in Examples 1-10 and Comparative Examples 1-3 were subjected to electrical performance tests, and the test results are shown in Table 1.

[0095] The capacity retention rate was determined as follows: at 60°C, it was discharged to 2.6V at 0.5C, left to stand for 5 minutes, charged to 4.25V at 0.5C, charged to 0.01C at constant voltage, left to stand for 5 minutes, activated at 0.01C for two weeks, and then charged and discharged at 0.5C.

[0096] Table 1

[0097] project Capacity retention rate (%) after 100 cycles at 0.5C Border cracking condition (100 circles) Example 1 Short circuit in the third circle Cracking (3rd ring) Example 2 Short circuit in 12th lap cracking Example 3 Short circuit on 89th lap No cracking Example 4 90.24％ No cracking Example 5 93.35％ No cracking Example 6 92.13％ No cracking Example 7 92.11％ No cracking Example 8 Short circuit on 22nd lap No cracking Example 9 90.06％ No cracking Example 10 91.32％ No cracking Comparative Example 1 91.12％ cracking Comparative Example 2 89.33％ cracking Comparative Example 3 Overcharged on lap 8 cracking

[0098] The test results from the examples and comparative examples show that in Examples 1-3, the binder content was too low, making them prone to short circuits and cracking during cycling. In Example 4, the binder content was increased, and the capacity retention rate after 100 cycles at 0.5C was 90.24%, with no cracking. In Example 8, the frame width was too low, making it prone to short circuits during cycling. In Examples 9 and 10, the frame width was increased, resulting in a decrease in the capacity retention rate during cycling. With the same binder and frame width content, the capacity retention rate of Example 5 was significantly higher than that of Comparative Examples 1-3, and no cracking occurred after 100 cycles. Therefore, the battery assembly of the present invention can effectively improve the structural stability and safety of the battery.

[0099] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A battery assembly, comprising: The battery assembly comprises a current collector, a negative active layer, a solid-state electrolyte layer, an insulating frame and a positive active layer; The negative active layer is arranged on at least one surface of the current collector in the thickness direction, the solid-state electrolyte layer is arranged on the surface of the negative active layer away from the current collector, and the insulating frame is arranged on the edge of the surface of the solid-state electrolyte layer away from the negative active layer; The outer edge of the insulating frame is equal to the circumference of the solid-state electrolyte layer; and the positive active layer is arranged in the inner frame area of the insulating frame. The material of the insulating frame comprises kaolin particles.

2. The battery assembly of claim 1, wherein, The frame width of the insulating frame is 1-5 mm; and / or, The thickness of the insulating frame is 30-200 μm; and / or, The thickness of the positive active layer is equal to the thickness of the insulating frame.

3. The battery assembly of claim 1, wherein, The D50 of the kaolin particles is 0.1-100 μm; and / or, The content of the kaolin particles is 50-99.9 wt% based on the total mass of the insulating frame.

4. The battery assembly of claim 1, wherein, The material of the insulating frame further comprises a binder, and the binder is coated on the surface of the kaolin particles. The content of the binder is 0.1-50 wt% based on the total mass of the insulating frame.

5. The battery assembly of claim 4, wherein, The binder comprises at least one of butyl benzene emulsion, polystyrene copolymer, butyl nitrile rubber, hydrogenated butyl nitrile rubber and polyvinylidene fluoride.

6. The battery assembly of claim 1, wherein, The current collector comprises at least one of carbon-coated copper foil, screen-printed copper foil, porous copper foil and copper mesh.

7. A method of making the battery assembly of any one of claims 1-6, characterized by, The method comprises the following steps: S1, mixing kaolin, a binder and a solvent to obtain a mixed slurry; S2, arranging a negative active material on at least one surface of a current collector in the thickness direction to obtain a first assembly; and arranging a solid-state electrolyte material on the surface of the first assembly to obtain a second assembly; S3, coating the mixed slurry on the circumferential area of the surface of the second assembly and performing drying treatment to obtain a third assembly with an insulating frame; S4, transferring a positive active layer into the inner frame area of the insulating frame of the third assembly.

8. The method of claim 7, wherein the battery assembly is prepared by a process comprising: The solvent comprises at least one of toluene, xylene, isobutyl isobutyrate, ethyl acetate, hexyl acetate, butyl acetate, benzyl butyrate, dichloroethane and heptane.

9. The method of claim 7, wherein the battery assembly is prepared by a process comprising: In step S1, the mixing conditions comprise a rotation speed of 400-3000 rpm and a mixing time of 1-10 min; and / or, In step S3, the drying conditions comprise a temperature of 25-100 °C and a time of 1-24 h.

10. An all-solid battery, characterized by, The all-solid-state battery comprises a battery assembly according to any one of claims 1-6 or prepared by the method according to any one of claims 7-9.

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