Material dispersing and grinding device, positive pole piece and all-solid-state battery

Abstract

The invention provides a material dispersing and grinding device, a positive pole piece and an all-solid-state battery, and relates to the technical field of batteries. The device comprises a first container, a second container, a first transmission mechanism and a second transmission mechanism, the first container is nested in the second container and is lower than the second container; a spirally rising grinding tooth array is arranged in a nesting gap between the two containers, and a feeding hole is formed in the bottom of the first container; the first container is driven by the first transmission mechanism to rotate in the first direction so as to drive to-be-ground materials in the first container to enter the nesting gap through the feeding hole. The second container is driven by the second transmission mechanism to rotate along an opposite second direction; and the grinding tooth array is used for dispersing and grinding the to-be-ground material entering the nesting gap, and pushing the ground material to move upwards to enter the first container in the rotating process, so that full mixing and uniform dispersion of the material are ensured through a circulating grinding mechanism, and the comprehensive performance of the all-solid-state battery is effectively improved.

Description

Technical Field

[0001] The present application relates to the technical field of batteries, and particularly to a material dispersion and grinding device, a positive electrode sheet, and a all-solid-state battery. Background Art

[0002] In recent years, with the rapid development of the electric vehicle industry, the market's comprehensive performance requirements for power batteries have been increasing day by day. Although traditional liquid lithium batteries perform excellently in terms of energy density and cycle life, due to technical bottlenecks such as safety hazards brought by the use of flammable organic electrolytes, performance degradation in low-temperature environments, and limited fast charging capabilities, they have seriously affected the popularization process of electric vehicles. In contrast, all-solid-state batteries use non-flammable inorganic solid electrolyte systems, which not only greatly improve the safety of the batteries but also can be compatible with electrode materials with higher energy densities (such as metal lithium anodes), showing significant technical advantages. In addition, the high ionic conductivity characteristics of solid electrolytes provide new possibilities for improving the rate performance of batteries, making them an important breakthrough for the next generation of power battery technologies. However, the commercialization process of all-solid-state batteries still faces major technical challenges, among which the key is the ion / electron transport efficiency problem at the solid-solid interface. The core of this problem lies in how to achieve uniform dispersion and close contact of components such as active materials, solid electrolytes, and conductive agents at the nanoscale during the preparation process of the electrode sheet.

[0003] In related technologies, traditional mechanical mixing methods such as high-speed shear dispersion or ball milling processes are usually adopted. Although these methods can achieve preliminary mixing of materials through high-speed rotating impellers, there are problems of uneven dispersion. Summary of the Invention

[0004] The present application provides a material dispersion and grinding device, a positive electrode sheet, and a all-solid-state battery to improve the problem of uneven material dispersion in related technologies.

[0005] In a first aspect, the present application provides a material dispersion and grinding device, including: a first container, a second container, a first transmission mechanism, and a second transmission mechanism. The first container is nested inside the second container, and the height of the first container is lower than that of the second container; a helically rising grinding tooth array is provided in the nested gap between the first container and the second container, and a feed hole is provided at the bottom of the first container; wherein:

[0006] The first container can rotate in a first direction under the drive of the first transmission mechanism to drive the material to be ground in the first container to enter the nested gap between the first container and the second container through the feed hole;

[0007] The second container can rotate in a second direction under the drive of the second transmission mechanism, and the first direction is opposite to the second direction;

[0008] The grinding tooth array is used to disperse and grind the material to be ground entering the nested gap, and push the material being ground upward during rotation into the first container.

[0009] In a possible implementation manner, the grinding tooth array is arranged in zebra stripes.

[0010] In a possible implementation manner, the spacing of the zebra stripes is 1 mm - 50 mm.

[0011] In a possible implementation manner, both the first container and the second container are conical structures.

[0012] In a possible implementation manner, the cone angle of the conical structure is 30° - 60°.

[0013] In a possible implementation manner, the rotation speed ranges of both the first container and the second container are 0 r / min - 2000 r / min.

[0014] In a possible implementation manner, the spiral rising angle of the grinding tooth array is 30° - 60°.

[0015] In a possible implementation manner, the height of the grinding teeth in the grinding tooth array is 0.1 mm - 1 mm; and / or, the tooth pitch of the grinding teeth in the grinding tooth array is 0.01 mm - 1 mm.

[0016] In a possible implementation manner, the diameter of the feed hole is 5 mm - 50 mm.

[0017] In a second aspect, the present application provides a positive electrode sheet, including a positive electrode current collector and a positive electrode active material layer provided on at least one surface of the positive electrode current collector, and the material of the positive electrode active material layer is selected from the powder material dispersed and ground by the material dispersion grinding device as described in any one of the first aspect.

[0018] In a third aspect, the present application provides a all-solid-state battery, including a positive electrode sheet, a negative electrode sheet and an electrolyte membrane, and the positive electrode sheet includes the positive electrode sheet described in the second aspect.

[0019] In a fourth aspect, the present application provides an electrical device, including the all-solid-state battery described in the third aspect.

[0020] The implementation of the present application has at least the following beneficial effects:

[0021] 1) By adopting a double-container nested structure and combining a spiral upward grinding tooth array set in the nested gap between the two containers, the material can move upward along a spiral path during the grinding process and fall back into the first container after reaching the top of the first container for re-dispersion grinding. This cyclic grinding mechanism effectively improves the problems of dead corners and uneven local dispersion that may occur in the traditional method, ensuring the full mixing and uniform dispersion of the material;

[0022] 2) The grinding tooth array not only realizes the dispersion grinding of the material, but also can effectively open the agglomerated coils of the linear conductive material, further ensuring its uniform distribution. Moreover, the grinding tooth array can further refine the particle size of the electrolyte and uniformly cover it on the surface of the active material, thereby realizing the effective coating of the electrolyte on the active material. This refinement and coating contribute to the construction of an efficient ion and electron transport path, thus effectively improving the comprehensive performance of the all-solid-state battery and providing key process support for the industrialization of high-energy-density and high-safety solid-state batteries;

[0023] 3) The design of the height difference between the first container and the second container enables the material to smoothly fall back into the inner container from the top during the circulation process, avoiding the problems of material accumulation and blockage during the grinding process and ensuring the smooth progress of the entire grinding process;

[0024] 4) This device can achieve efficient material dispersion within a short time, such as 5 to 20 minutes, significantly improving the production efficiency and better meeting the requirements of industrial large-scale production. Description of the Drawings

[0025] The drawings here are incorporated into the specification and form a part of this specification, showing embodiments consistent with this application and used together with the specification to explain the principles of this application.

[0026] Figure 1 It is a schematic structural diagram of a material dispersion and grinding device provided for an exemplary embodiment of this application.

[0027] Description of the Reference Numerals in the Drawings

[0028] 10. Material dispersion and grinding device; 11. First container; 12. Second container; 13. First transmission mechanism; 14. Second transmission mechanism; 15. Grinding tooth array; 16. Feed hole; 17. Material to be ground.

[0029] Through the above drawings, the clear embodiments of this application have been shown, and there will be more detailed descriptions hereinafter. These drawings and textual descriptions are not intended to limit the scope of the concept of this application in any way, but to illustrate the concept of this application to those skilled in the art by referring to specific embodiments. Detailed Embodiments

[0030] To make the objectives, technical solutions, and advantages of the present invention clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0031] In related technologies, traditional mechanical mixing methods such as high-speed shear dispersion or ball milling processes are usually adopted, relying on high-speed rotating impellers or ball milling media to mechanically mix materials. Due to the structural limitations of the stirring impeller or ball milling tank, "dead corners" are easily formed during the mixing process, and some materials cannot come into full contact, only achieving preliminary mixing. It is difficult to ensure the uniform distribution of active materials, solid electrolytes, and conductive agents such as vapor-grown carbon fiber (VGCF for short) and carbon nanotube (CNT for short) at the nanoscale. Moreover, linear conductive agents such as VGCF and CNT are prone to forming clusters due to van der Waals forces, and traditional mechanical mixing cannot effectively break open their agglomerated structures, resulting in an incomplete construction of the conductive network and affecting the electron transport efficiency. Solid electrolytes (such as sulfide electrolytes, etc.) usually have a low Young's modulus and are prone to plastic deformation rather than effective refinement during high-speed shearing, resulting in uneven coating on the surface of active materials and affecting ion transport. In addition, traditional mixing equipment cannot meet the uniform mixing of ultra-fine powders (such as nano-scale electrolytes) and active materials, resulting in a large number of interface defects inside the electrode film, increasing the solid-solid contact impedance, making the electron conduction path discontinuous, and affecting the battery rate performance.

[0032] Based on the technical problems existing in related technologies, the present application proposes a material dispersion and grinding device, which adopts a cyclic grinding method to enable the electrolyte, conductive agent, and active material in the material to come into full contact during the grinding process, achieving uniform dispersion and grinding of the material, so that the electrolyte and conductive agent uniformly surround the surface of the active material particles, thereby constructing an effective ion and electron transport path, and further effectively improving the comprehensive performance of all-solid-state batteries, providing key process support for the industrialization of high-energy density and high-safety solid-state batteries.

[0033] The following will specifically describe the technical solutions of the present application and how the technical solutions of the present application solve the above technical problems through specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The following will describe the embodiments of the present application in conjunction with the drawings.

[0034] Figure 1A structural schematic diagram of the material dispersion and grinding device provided by an exemplary embodiment of the present application. As Figure 1 shown, the material dispersion and grinding device 10 includes:

[0035] A first container 11, a second container 12, a first transmission mechanism 13, and a second transmission mechanism 14. The first container 11 is nested inside the second container 12, and the height of the first container 11 is lower than that of the second container 12. A helically ascending grinding tooth array 15 is provided in the nested gap between the first container 12 and the second container 12, and a feed hole 16 is provided at the bottom of the first container 11. Among them:

[0036] The first container 11 can rotate in a first direction under the drive of the first transmission mechanism 13 to drive the material 17 to be ground in the first container 11 to enter the nested gap between the first container 11 and the second container 12 through the feed hole 16;

[0037] The second container 12 can rotate in a second direction under the drive of the second transmission mechanism 14, and the first direction is opposite to the second direction;

[0038] The grinding tooth array 15 is used to disperse and grind the material 16 to be ground entering the nested gap, and push the material being ground upward during the rotation process to enter the first container 11.

[0039] Among them, the first transmission mechanism 13 is arranged along the axis direction of the first container 11, and is used to support the first container 11 and drive the first container 11 to rotate around its central axis; the second transmission mechanism 14 is arranged along the axis direction of the second container 12, and is used to support the second container 12 and drive the second container 12 to rotate around its central axis.

[0040] Exemplarily, as Figure 1 shown, the material to be dispersed and ground is added into the first container 11. The rotation speed of the first container 11 is set to 1000 r / min, and the rotation speed of the second container 12 is set to 500 r / min. The first container 11 rotates clockwise under the drive of the first transmission mechanism 13 to drive the material 17 to be ground in the first container 11 to enter the nested gap between the first container 11 and the second container 12 through the feed hole 16. The second container 12 rotates counterclockwise under the drive of the second transmission mechanism 14. The grinding tooth array 15 disperses and grinds the material 16 to be ground entering the nested gap, and pushes the material 16 being ground upward during the high-speed rotation process. Since the height of the first container 11 is lower than that of the second container 12, the material being ground moves upward to the top of the first container 11 and then slides into the first container 11, thereby realizing the cyclic grinding of the material to be ground in the structural member and achieving the effect of uniform dispersion.

[0041] It should be noted that the first container 11 rotates in the clockwise direction driven by the first transmission mechanism 13, and at the same time, the second container 12 rotates in the counterclockwise direction driven by the second transmission mechanism 14 is only an example; in practical applications, the first container 11 can also rotate in the counterclockwise direction driven by the first transmission mechanism 13, and at the same time, the second container 12 rotates in the clockwise direction driven by the second transmission mechanism 14, or one of the first container 11 and the second container 12 does not rotate, and the other container rotates clockwise or counterclockwise, and no specific limitation is made thereto.

[0042] It should be further noted that the grinding tooth array 15 can be arranged on the outer side surface of the first container 11, or can be arranged on the inner side surface of the second container 12, and no limitation is made to the arrangement position of the grinding tooth array 15 here.

[0043] In a specific embodiment, both the first container and the second container are of a conical structure.

[0044] Exemplarily, still referring to Figure 1 , both the first container 11 and the second container 12 are of a conical structure.

[0045] In another embodiment, the first container and the second container can also be of a structure with arc-shaped outer walls. Exemplarily, different from the conical structure shown in Figure 1 , the outer walls of the first container 11 and the second container 12 adopt a single-curvature or multi-curvature arc surface, for example, its radius of curvature is R, and the arc surface angle is α, forming a smooth and continuous arc envelope surface.

[0046] It should be noted that the above-mentioned conical structure and arc-shaped outer wall structure are only examples. In practical applications, the designs of the first container 11 and the second container 12 can be flexibly adjusted. For example, only the lower end of the container adopts an arc surface structure or a conical structure, etc., and no specific limitation is made to the structures of the first container 11 and the second container 12 here.

[0047] By adopting a double-container nested structure and combining a helically ascending grinding tooth array arranged in the nested gap between the two containers, the material can move upward along a spiral path during the grinding process and fall back into the first container after reaching the top of the first container for re-dispersion and grinding. This cyclic grinding mechanism effectively improves the problems of dead corners and uneven local dispersion that may occur in traditional methods, ensuring the full mixing and uniform dispersion of the material; the grinding tooth array not only realizes the dispersion and grinding of the material, but also can effectively open the agglomerated coils of the linear conductive material, further ensuring its uniform distribution, and the grinding tooth array can refine the particle size of the electrolyte and uniformly cover the surface of the active material, realizing the effective coating of the electrolyte on the active material. This refinement and coating help to construct an efficient ion and electron transport path, thus effectively improving the comprehensive performance of the all-solid-state battery and providing key process support for the industrialization of high-energy-density and high-safety solid-state batteries; in addition, due to the height difference design between the first container and the second container, the material can smoothly fall back into the inner container from the top during the circulation process, avoiding the accumulation and blockage of the material during the grinding process and ensuring the smooth progress of the entire grinding process; furthermore, since the device can achieve efficient material dispersion in a relatively short time, such as 5 to 20 minutes, the production efficiency is significantly improved, and it can better meet the needs of industrial large-scale production.

[0048] In a specific embodiment, the cone angle of the cone structure is 30° - 60°.

[0049] Exemplarily, when both the first container and the second container are of a cone structure, the cone angles of the first container and the second container are the same; specifically, the cone angles of the first container and the second container can be 30°, 31°, 32°, 33°, 34°, 35°, 36°, 37°, 38°, 39°, 40°, 41°, 42°, 43°, 44°, 45°, 46°, 47°, 48°, 49°, 50°, 51°, 52°, 53°, 54°, 55°, 56°, 57°, 58°, 59°, 60° or the range composed of any two of them, which helps to optimize the fluidity of the material to be ground during the grinding process, ensures that the material evenly rises along the cone surface during rotation and smoothly falls back after reaching the top. This flow pattern helps to improve the grinding efficiency and ensure the uniform dispersion of the material; at the same time, the appropriate cone angle design can prevent the material from accumulating or blocking during the grinding process, enabling the material to smoothly circulate in the cone and avoiding dead corners and uneven local distribution. Generally speaking, the design of the cone angle of the cone structure being 30° - 60° plays a key role in ensuring the efficient circulation, uniform dispersion of the material and preventing accumulation, thus improving the performance and efficiency of the entire dispersion and grinding.

[0050] In a specific embodiment, the grinding tooth array is arranged in zebra stripe patterns.

[0051] Exemplarily, the grinding tooth array is distributed in an intermittent spiral strip shape along the outer side surface of the first container, forming an alternating light and dark zebra stripe pattern. Among them, the bright band area is the toothed area, and its shear strength is greater than, for example, 1×105 Pa, etc., and the dark band area is the toothless area, forming a material tumbling space; or, the dark band area is the toothed area, and its shear strength is greater than, for example, 1×105 Pa, etc., and the bright band area is the toothless area, forming a material tumbling space.

[0052] In the embodiment of the present application, by arranging the grinding tooth array in a zebra stripe pattern, the material experiences strong shearing of the grinding teeth and relative relaxation in the toothless area alternately during movement by means of the striped intervals, preventing material caking caused by excessive compression, which is particularly important for sulfide electrolytes with low Young's modulus; in addition, the blank areas between the stripes provide a tumbling space for the powder, ensuring uniform contact in three dimensions and avoiding layered segregation caused by unidirectional stress; and intermittent grinding can reduce the local high temperature generated by continuous friction, helping to inhibit the high-temperature phase change of the material.

[0053] In a specific embodiment, the spacing of the zebra stripes is 1 mm - 50 mm.

[0054] Exemplarily, the spacing of the zebra stripes is 1 mm, 5 mm, 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, 45 mm, 50 mm or the range composed of any two of them. By controlling the spacing of the zebra stripes within the range of 1 mm - 50 mm, the performance of the grinding device can be significantly improved, ensuring efficient grinding and uniform dispersion of the material, so as to meet the requirements of different application scenarios.

[0055] In a specific embodiment, the rotation speed range of the first container and the rotation speed range of the second container are both 0 r / min - 2000 r / min.

[0056] Exemplarily, the rotational speeds of both the first container and the second container can be 0 r / min, 100 r / min, 200 r / min, 300 r / min, 400 r / min, 500 r / min, 600 r / min, 700 r / min, 800 r / min, 900 r / min, 1000 r / min, 1100 r / min, 1200 r / min, 1300 r / min, 1400 r / min, 1500 r / min, 1600 r / min, 1700 r / min, 1800 r / min, 1900 r / min, 2000 r / min, or a range composed of any two of them. However, during the grinding process, the rotational speeds of the first container and the second container cannot be 0 r / min simultaneously. By controlling the rotational speed ranges of the first container and the second container within 0 r / min - 2000 r / min, precise adjustment is allowed according to the characteristics of different materials and grinding requirements. By adjusting the rotational speed, rapid dispersion and uniform grinding of the materials can be achieved, thereby improving the overall grinding efficiency. Additionally, when high speeds are not required, lower rotational speeds can be selected for operation, thus reducing energy consumption, helping to lower the operating cost, and selecting appropriate rotational speeds can also reduce equipment wear, thereby extending the service life of the equipment.

[0057] In a specific embodiment, the spiral rising angle of the grinding tooth array is 30° - 60°.

[0058] Exemplarily, the spiral rising angle of the grinding tooth array is 30°, 31°, 32°, 33°, 34°, 35°, 36°, 37°, 38°, 39°, 40°, 41°, 42°, 43°, 44°, 45°, 46°, 47°, 48°, 49°, 50°, 51°, 52°, 53°, 54°, 55°, 56°, 57°, 58°, 59°, 60°, or a range composed of any two of them. By setting the spiral rising angle of the grinding tooth array between 30° and 60°, it helps to effectively push the material upward during the grinding process, enabling it to achieve full circulation within the container. This design ensures the uniform distribution and continuous grinding of the material. Moreover, an appropriate spiral angle can increase the contact time and contact area between the material and the grinding teeth, thereby improving the grinding efficiency, promoting the refinement and uniform dispersion of the material. At the same time, it can effectively prevent the material from piling up during the grinding process, ensuring the smooth progress of the grinding process. Additionally, the design of the spiral rising angle helps to enhance the mixing effect of the material, reduce dead corners and uneven dispersion problems, and this angle range can adapt to materials with different physical properties, providing greater application flexibility and being able to meet the grinding requirements of different materials.

[0059] In a specific embodiment, the height of the grinding teeth in the grinding tooth array is 0.1 mm - 1 mm; and / or, the tooth pitch of the grinding teeth in the grinding tooth array is 0.01 mm - 1 mm.

[0060] Exemplarily, in one implementation, the height of the grinding teeth in the grinding tooth array is 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, or a range composed of any two of them.

[0061] In another implementation, the tooth pitch of the grinding teeth in the grinding tooth array is 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, or a range composed of any two of them.

[0062] In yet another implementation, the height of the grinding teeth in the grinding tooth array is 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, or a range composed of any two of them; and the tooth pitch of the grinding teeth in the grinding tooth array is 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, or a range composed of any two of them.

[0063] In the embodiments of the present application, the fine design of the height and tooth pitch of the grinding teeth can perform more refined grinding on the material, which helps to improve the uniformity and refinement degree of the material, and the appropriate tooth pitch helps to more effectively disperse the material, reduce the agglomeration phenomenon, and ensure the uniform distribution of the material during the grinding process. By adjusting the height and pitch of the teeth, the grinding efficiency can be optimized, making the grinding process more efficient, and the reasonable design of the tooth height and pitch can reduce the wear of the equipment, help to extend the service life of the equipment, and at the same time reduce the maintenance cost of the equipment.

[0064] In a specific embodiment, the diameter of the feed hole is 5 mm - 50 mm.

[0065] Exemplarily, the diameter of the feed hole is 5 mm, 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, 45 mm, 50 mm, or a range composed of any two of them. By controlling the diameter of the feed hole within the range of 5 mm - 50 mm, it is possible to adapt to materials with different particle sizes and shapes. According to different process requirements, an appropriate feed hole diameter can be selected to meet specific production needs and quality standards, thereby ensuring the versatility and flexibility of the equipment. Moreover, an appropriate feed hole diameter can control the feeding speed, ensure that the material enters the grinding area evenly, improve the grinding efficiency and effect, and at the same time help prevent the material from clogging during the feeding process, ensuring the continuous and stable operation of the equipment. This is of positive significance for improving production efficiency, reducing downtime, and material waste.

[0066] The present application also provides a positive electrode sheet, which includes a positive electrode current collector and a positive electrode active material layer provided on at least one surface of the positive electrode current collector. The material of the positive electrode active material layer is selected from the powder materials dispersed and ground by the above-mentioned material dispersion and grinding device.

[0067] Among them, the material of the positive electrode current collector can be at least one of aluminum foil and nickel foil; the conductive agent can be selected from at least one of carbon black, acetylene black, graphene, Ketjen black, carbon fiber, or carbon nanotube; the binder can be selected from at least one of polytetrafluoroethylene, polyvinylidene fluoride, polyvinyl fluoride, polyethylene, polypropylene, polyvinyl alcohol, carboxymethyl cellulose, hydroxypropyl cellulose, diacetyl cellulose, polyvinyl chloride, carboxylated polyvinyl chloride, polymers containing ethylene oxide, polyvinylpyrrolidone, and polyurethane.

[0068] The present application also provides a all-solid-state battery, which includes a positive electrode sheet, a negative electrode sheet, and an electrolyte membrane. The positive electrode sheet includes the positive electrode sheet described in the second aspect.

[0069] The present application does not strictly limit the negative electrode active material in the negative electrode sheet, which can be the negative electrode active materials commonly used in current lithium-ion batteries, such as at least one of graphite, hard carbon, soft carbon, mesophase carbon microspheres, silicon-based negative electrode materials (mainly including silicon monoxide and silicon-carbon negative electrodes), and tin-based negative electrode materials (mainly including tin and tin alloys).

[0070] The present application does not strictly limit the selection of the electrolyte membrane, and various solid electrolyte material systems and their preparation processes known in the art can be adopted according to actual application requirements. Exemplarily, the electrolyte membrane can adopt a composite material system of Li6PS5Cl:PTFE = 99:1 (mass ratio), and a dry electrolyte membrane with excellent mechanical strength and interfacial contact characteristics is formed through fibrillation treatment combined with a continuous roll pressing process. However, it should be noted that those skilled in the art can make reasonable adjustments in the following dimensions according to specific application scenarios: for example, the material system can select sulfide systems, oxide systems, polymer systems, etc., or binary or ternary composites of sulfide systems, oxide systems, polymer systems, etc.; the content of the binder PTFE can be adjusted between 0.5 - 5 wt%, or can be replaced by at least one of different binders such as PVDF, CMC, SBR, NBR, H-NBR, SEBS, SBS, PIB, or BR, or a multi-binder composite system (such as PTFE + PEO) can be adopted. Those skilled in the art can understand that reasonable adjustments to the material ratio, preparation process, and structural design of the electrolyte membrane, without departing from the core concept of the present invention, should fall within the protection scope of this patent. This flexible design space enables this technical solution to adapt to the requirements of different application scenarios from 3C electronic products to power batteries.

[0071] The present application does not make special limitations on the preparation method of the all-solid-state battery, and it can be prepared by referring to conventional methods in the art.

[0072] For example, in a specific embodiment, the all-solid-state battery can be prepared through the following steps:

[0073] Stack and assemble the pre-prepared negative electrode sheet, electrolyte membrane, and positive electrode sheet in a predetermined order; subsequently, use a hot pressing process to form good interfacial contact between the layers of materials; then, perform encapsulation treatment on the assembled battery cell; finally, further improve the interfacial bonding strength between the electrode and the electrolyte through an isostatic pressing process, thereby obtaining an all-solid-state battery with stable performance.

[0074] The present application also provides an electrical device including the above-mentioned all-solid-state battery.

[0075] The present application does not make special limitations on the electrical device, and it can be any electrical device including this all-solid-state battery, and this electrical device includes but is not limited to mobile phones, portable devices, laptop computers, electric bicycles, electric vehicles, electric toys, and energy storage devices, etc.

[0076] Hereinafter, the material dispersion and grinding device and the all-solid-state battery provided by the present application will be further introduced in combination with specific embodiments.

[0077] Unless otherwise specified, the reagents, materials and instruments used in the following examples are conventional reagents, conventional materials and conventional instruments in the art and can be obtained commercially. The reagents involved can also be synthesized by conventional methods in the art.

[0078] Example 1

[0079] This embodiment provides an all-solid-state battery, and the preparation method thereof is as follows:

[0080] 1. Add the positive electrode material NCM811 for all-solid-state batteries, the sulfide electrolyte Li6PS5Cl and the conductive carbon VGCF in a mass ratio of 80:17:3 to Figure 1 In the first container shown, the first container is set to rotate in a clockwise direction at a speed of 1000 r / min; the second container is set to rotate in a counterclockwise direction at a speed of 1000 r / min; the material dispersing and grinding device is stopped after running for 20 minutes, and the dispersed powder is taken out for use.

[0081] 2. Take an appropriate amount of dispersed powder and add 0.5% by mass of PTFE, and then continuously roll-press it to form a composite positive electrode sheet after fiberization treatment.

[0082] 3. Nano-silicon, carbon nanotubes and polyacrylic acid binder are uniformly mixed in a mass ratio of 95:2:3, and the slurry is coated on the surface of the current collector after being prepared. After drying, a negative electrode sheet with a stable structure is formed.

[0083] 4. The Li6PS5Cl solid electrolyte powder and the PTFE binder are uniformly mixed in a mass ratio of 99:1, subjected to mechanical fiberization treatment to form a three-dimensional network structure, and then prepared into a self-supporting dry electrolyte membrane with good flexibility and ion conductivity through a multi-stage rolling process.

[0084] 5. Battery assembly: Die-cut the above positive electrode sheets, negative electrode sheets and electrolyte membranes into the designed size, stack and assemble them in a predetermined order, and hot press them at 120°C and 0.5MPa for 60s to achieve electrode-electrolyte interface fusion; then load the bare battery cells into the soft-pack material and perform warm isostatic pressing at a pressure of 400MPa for 3min to obtain an all-solid-state battery.

[0085] 6. Charge and discharge the assembled battery, for example, charge at a constant current of 0.1C to 4.25V, then charge at a constant voltage until the current drops to 0.05C, stop charging, and discharge at a constant current of 0.1C to 2.5V after 5 minutes, and record the first charge specific capacity, first discharge specific capacity and first charge and discharge efficiency. Among them, the first charge and discharge efficiency = (first discharge specific capacity / first charge specific capacity) * 100%.

[0086] Comparative Example

[0087] This comparative example provides a all-solid-state battery, and its preparation method is basically the same as that of Example 1. The difference is that the dispersion method of the cathode material is manual grinding with a traditional agate mortar, and the grinding time is 20 minutes.

[0088] Exemplarily, the initial charge specific capacity, the initial discharge specific capacity, and the initial charge-discharge efficiency in Example 1 and Comparative Example 1 are shown in Table 1.

[0089] Table 1

[0090] Item Initial Charge Specific Capacity mAh / g Initial Discharge Specific Capacity mAh / g Initial Charge-Discharge Efficiency % Example 1 223.4 204.3 91.4 Comparative Example 1 228.5 198.2 86.7

[0091] Based on the data shown in Table 1, the following conclusions can be analyzed:

[0092] Compared with the all-solid-state battery prepared from the powder obtained by manual grinding and dispersion with a traditional agate mortar, for the all-solid-state battery prepared from the powder obtained by dispersion with the material dispersion and grinding device, its initial discharge specific capacity has increased by 3.1%, and its initial charge-discharge efficiency (91.4%) is significantly higher than the initial charge-discharge efficiency (86.7%) of Comparative Example 1, indicating that the above-mentioned material dispersion and grinding device ensures the sufficient mixing and uniform dispersion of the materials through dynamic grinding, which helps to construct an efficient ion and electron transport path and significantly improves the comprehensive performance of the all-solid-state battery.

[0093] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and are not intended to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A material dispersing and grinding device, characterized in that: include: A first container, a second container, a first transmission mechanism and a second transmission mechanism, wherein the first container is nested inside the second container, and the height of the first container is lower than the height of the second container; a spirally ascending grinding tooth array is provided in the nesting gap between the first container and the second container, and a feeding hole is provided at the bottom of the first container; wherein: The first container can rotate in a first direction under the drive of the first transmission mechanism to drive the material to be ground in the first container to enter the nesting gap between the first container and the second container through the feed hole; The second container can rotate along a second direction under the driving of the second transmission mechanism, and the first direction is opposite to the second direction; The grinding tooth array is used to disperse and grind the material to be ground that enters the nesting gap, and to push the material being ground to move upward into the first container during rotation.

2. The material dispersing and grinding device according to claim 1, characterized in that: The grinding tooth array is arranged in zebra stripes.

3. The material dispersing and grinding device according to claim 2, characterized in that: The spacing between the zebra stripes is 1mm-50mm.

4. The material dispersing and grinding device according to any one of claims 1 to 3, characterized in that: The first container and the second container are both conical structures, and the cone angle of the conical structure is 30°-60°.

5. The material dispersing and grinding device according to any one of claims 1 to 3, characterized in that: The rotation speed range of the first container and the rotation speed range of the second container are both 0 r / min-2000 r / min.

6. The material dispersing and grinding device according to any one of claims 1 to 3, characterized in that: The spiral rise angle of the grinding tooth array is 30°-60°.

7. The material dispersing and grinding device according to any one of claims 1 to 3, characterized in that: The height of the grinding teeth in the grinding tooth array is 0.1 mm - 1 mm; And / or, the tooth spacing of the grinding teeth in the grinding tooth array is 0.01mm-1mm.

8. The material dispersing and grinding device according to any one of claims 1 to 3, characterized in that: The diameter of the feed hole is 5mm-50mm.

9. A positive electrode sheet, characterized in that: It comprises a positive electrode current collector and a positive electrode active material layer arranged on at least one side surface of the positive electrode current collector, wherein the material of the positive electrode active material layer is selected from the powder material dispersed and ground by the material dispersing and grinding device according to any one of claims 1 to 8.

10. An all-solid-state battery, comprising a positive electrode sheet, a negative electrode sheet and an electrolyte membrane, characterized in that: The positive electrode sheet comprises the positive electrode sheet as claimed in claim 9.

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