All-solid-state battery composite electrode with ordered ion transmission channel and preparation method of all-solid-state battery composite electrode

Abstract

The invention relates to an all-solid-state battery composite electrode with an ordered ion transmission channel and a preparation method of the all-solid-state battery composite electrode, the composite electrode comprises a primary ion transmission channel part, a secondary ion transmission channel and an active material part, the primary ion transmission channel part comprises 5-20 parts of a solid electrolyte and 0.1-10 parts of a binder, the secondary ion transmission channel and active material part comprises 50-90 parts of an electrode active material, 5-50 parts of a solid electrolyte, 0.1-10 parts of an electronic conductive agent and 0.1-10 parts of a binder, the mass ratio of the solid electrolyte of the two-stage part is (5-20): (5-50), the two-stage part is formed by mixing and processing raw materials into sheets, overlapping the sheets, rolling and compounding the sheets, and repeatedly folding and rolling or rolling and winding the sheets into blocks. And cutting into the all-solid-state battery composite electrode with the ordered ion transmission channel. Compared with the prior art, the material is wide in applicability, simple and efficient, and high-rate cycle performance is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of secondary batteries and relates to an all-solid-state battery composite electrode with ordered ion transport channels and a preparation method thereof. Background Art

[0002] As fossil energy reserves become increasingly depleted, global energy structural contradictions become increasingly prominent. Secondary lithium-ion batteries, with their significant advantages such as high specific energy, have been widely used in many fields. However, the liquid electrolyte solutions used in current commercial lithium-ion batteries have problems such as poor temperature adaptability, easy leakage, and susceptibility to fire and explosion. Furthermore, they are difficult to use with high-energy anode materials, which limits the further development of battery specific energy.

[0003] All-solid-state lithium batteries are considered one of the next-generation electrochemical energy storage devices with the potential to address the current problems of lithium-ion batteries. However, compared to existing lithium-ion batteries, reported all-solid-state lithium batteries still lack energy and power density. One reason is that the ion transport network within their composite electrodes is more complex and tortuous. Therefore, designing the composition and structure of the composite electrode is crucial to achieving efficient lithium ion transport and is one of the keys to promoting the practical application of all-solid-state lithium batteries.

[0004] In the report (Nano Energy 61 (2019) 567-575), the researchers used water as the main solvent of the slurry based on the principle of ice growth dynamics. The ice layer was removed by freeze-drying the electrode after scraping, thereby shaping vertical channels inside the thick electrode. The polymer solid electrolyte was then pressed into the ice layer to obtain a lithium iron phosphate (LFP) electrode (VL-LFP) with a vertically arranged structure. The electrode loading was 10.5 mg cm 2 When the battery is heated at a low rate (~0.2C), high battery energy density can be achieved. However, this method uses water as the electrode slurry solvent and cannot use ternary materials as the active main material, which lacks applicability.

[0005] In the report (Chemical Engineering Journal 2023, 451, 138651), the researchers first formed a slurry of LFP active material, carbon black, carbon nanofibers, polyvinylidene fluoride-hexafluoropropylene copolymer (PVDF-HFP) binder and polyvinyl pyrrolidone (PVP) in N-methylpyrrolidone (NMP) solvent, coated it on a polyethylene terephthalate (PET) release membrane and immersed it in a water bath. The rapid exchange of solvent and water induced phase separation, forming a PVDF-HFP skeleton structure with vertical channels. The solid polyelectrolyte then filled the electrode pores and vertical channels, while tightly coating the active material to form a composite electrode with vertical ion transport channels. The composite electrode has a loading of 15 mg cm2 It exhibits excellent cycling stability, with a capacity retention of 89.0% after 250 cycles at 1C.

[0006] However, the above method of liquid phase introduction and then solidification has great limitations. First, the solid electrolyte in the form of liquid penetrates into the channel and then is dried and solidified, which causes a large volume change and is prone to contact loss, which greatly increases the porosity and reduces the ionic conductivity of the composite electrode. Secondly, the above wet method of preparing all-solid-state battery composite electrodes involves the use of a variety of organic materials, which has great pollution and cost issues. More importantly, the above method has great limitations on the material system used: solid electrolyte materials of sulfide, halide and other systems are difficult to apply the above construction method because there is a lack of stable and effective solvents to introduce the solid electrolyte in liquid phase. At present, there is still a lack of a simpler and more feasible technical solution that is applicable to various types of solid electrolyte materials and active material materials. Without affecting the content of electrode active materials, it can effectively improve the ion transport in the composite electrode and further improve the performance of thick composite electrodes.

[0007] Patent CN117352663A proposes a method for preparing a composite positive electrode for solid-state batteries using magnetic field induction technology. The method involves combining ion conductor nanowires / sheets (such as LLTO and LLZO) with magnetic nanoparticles to form a magnetically responsive material. This material is then mixed with a positive electrode active material (50-80%), a conductive agent, a binder, and a lithium salt in a solvent to form a slurry. After coating the current collector, a vertical / rotating magnetic field is applied to evaporate the solvent, driving the magnetic nanostructures to align vertically to form ion channels that run through the electrode. However, this patent still uses a method of dissolving the active material in a solvent to form a slurry, followed by coating and drying. Coating and drying the electrode results in significant changes in electrode volume, making it prone to contact loss between materials, significantly increasing the electrode's porosity, and increasing the tortuosity of ion transport. Furthermore, the magnetic nanoparticles remain in the electrode, reducing its ionic conductivity and potentially inducing side reactions. Furthermore, high-magnetic field equipment is expensive, making it difficult to commercialize.

[0008] Patent CN118867139A proposes a dry-process integrated composite positive electrode preparation method. Through supersonic airflow dispersion and multi-stage hot rolling technology, dual-size solid electrolyte particles (nanoscale coated active material, micron-scale shortened ion path) and conductive carbon network are integrated into the electrode membrane, and hot-pressed and fused with the solid electrolyte membrane to eliminate interfacial gaps. Femtosecond laser is used to construct vertical channels through the two layers to optimize ion / electron transmission paths. However, this patent still has shortcomings. On the one hand, the laser process may cause irreversible damage to the electrode material during the hole-making process, and the universality of the patented method is not high. The multi-stage hot rolling technology is difficult to apply to electrolyte materials with insufficient mechanical strength such as sulfides and polymers. On the other hand, the excessive reliance on precision laser technology has low mass production efficiency and high mass production costs. Summary of the Invention

[0009] The purpose of the present invention is to overcome at least one of the defects of the above-mentioned prior art and provide an all-solid-state battery composite electrode with ordered ion transport channels and a preparation method thereof. The material of the present invention has wide applicability and is simple and efficient while achieving high-rate cycle performance.

[0010] The purpose of the present invention can be achieved by the following technical solutions:

[0011] One of the technical solutions of the present invention is to provide an all-solid-state battery composite electrode with an ordered ion transport channel. The composite electrode includes a primary ion transport channel portion and a secondary ion transport channel and active material portion. As an ordered channel for ion transport, the raw materials of the primary ion transport channel portion include 5 to 20 parts of a solid electrolyte and 0.1 to 10 parts of a binder. As a place where an electrochemical reaction occurs, the raw materials of the secondary ion transport channel and active material portion include 50 to 90 parts of an electrode active material, 5 to 50 parts of a solid electrolyte, 0.1 to 10 parts of an electronic conductive agent, and 0.1 to 10 parts of a binder. The mass ratio of the solid electrolyte of the primary ion transport channel portion to the solid electrolyte of the secondary ion transport channel and active material portion is (5 to 20):(5 to 50).

[0012] The primary ion transport channel part and the secondary ion transport channel and the active material part are each processed into sheets by mixing raw materials, overlapping and rolling them together, repeatedly folding and rolling or roll-winding them into blocks, and cutting them into all-solid-state battery composite electrodes with ordered ion transport channels.

[0013] Furthermore, the electrode active material is selected from lithium cobalt oxide (LiCoO2), lithium nickel oxide (LiNiO2), lithium manganese oxide (LiMn2O4), lithium cobalt phosphate (LiCoPO4), lithium iron phosphate (LiFePO4), lithium nickel cobalt manganese oxide (NCM ternary material, LiNi x Co yMn z O2), lithium sulfide (Li2S), in powder form.

[0014] Furthermore, the solid electrolyte is selected from one or more of a sulfide solid electrolyte, a halide solid electrolyte, and a polymer solid electrolyte; the sulfide solid electrolyte is selected from one or more of lithium phosphorus sulfur chloride (Li6PS5Cl), lithium phosphorus sulfur bromine (Li6PS5Br), and lithium thiophosphate (Li3PS4); the halide solid electrolyte is selected from one or more of lithium indium chloride (Li3InCl6), lithium zinc chloride (Li2ZnCl4), and lithium ytterbium chloride (Li3YbCl6); and the polymer solid electrolyte is selected from one or more of a polyethylene oxide (PEO)-based electrolyte, a polyacrylonitrile (PAN)-based electrolyte, and a polyvinylidene fluoride (PVDF)-based electrolyte.

[0015] Furthermore, the electronic conductive agent is selected from one or more of carbon black, carbon nanotubes, acetylene black, carbon fiber, and graphene.

[0016] Furthermore, the binder is selected from one or more of polytetrafluoroethylene (PTFE), polyethylene oxide, polyacrylonitrile, polyvinyl pyrrolidone (PVP), polyvinylidene fluoride, and cellulose.

[0017] One of the technical solutions of the present invention is to provide a method for preparing the all-solid-state battery composite electrode with ordered ion transport channels, the method comprising the following steps:

[0018] S1. Mixing a solid electrolyte and a binder to obtain a primary channel sheet, and mixing an electrode active material, a solid electrolyte, an electronic conductive agent, and a binder to obtain a secondary channel and active material sheet;

[0019] S2, overlapping the primary channel sheet and the secondary channel sheet with the active material sheet and rolling and compounding them to obtain a composite sheet, and then,

[0020] S2.1, repeatedly folding and rolling the composite sheet to obtain a block with layered multi-level ion transport channels, or

[0021] S2.2. Rolling and thinning the composite sheet, and then winding the composite sheet to obtain a block having a spirally distributed multi-level ion transport channel;

[0022] S3, cutting the block at a certain angle to the primary channel sheet to obtain a composite electrode sheet with ordered ion transport channels;

[0023] S4. Separate or overlap one or more composite electrode sheets to obtain an all-solid-state battery composite electrode with ordered ion transport channels.

[0024] As a preferred technical solution, in step S1, the time for mixing the solid electrolyte and binder of the primary channel sheet is 20 to 40 minutes, the time for mixing the electrode active material, solid electrolyte and electronic conductive agent of the secondary channel and active material sheet is 20 to 40 minutes, and the time for mixing the binder of the secondary channel and active material sheet is 20 to 40 minutes.

[0025] Furthermore, in step S2 , the width of each level of the ion transmission channel is 5 to 100 μm.

[0026] Furthermore, in step S3, the cutting angle with respect to the primary channel sheet is 5 to 90°.

[0027] Furthermore, the thickness of the composite electrode sheet in step S3 is 5 to 500 μm to cope with all-solid-state batteries of different requirements, and the cut surface serves as the contact surface with the all-solid-state battery components.

[0028] Furthermore, in step S4, when multiple composite electrode plates with the same or different structures and the same or different thicknesses overlap, the composite electrode plates are cross-recombined with the cut surfaces as contact surfaces and the ion transmission channels of different plates forming an angle of 0 to 90 degrees.

[0029] One of the technical solutions of the present invention is to provide an application of the all-solid-state battery composite electrode with ordered ion transport channels in an all-solid-state battery, and to assemble an all-solid-state battery by sequentially combining the composite electrode as a positive electrode or a negative electrode, a solid electrolyte, and a counter electrode.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] (1) The present invention continuously thins the primary ion transmission channel and the secondary ion transmission channel by folding, rolling, and winding, so as to keep the width of the ion transmission channels at various levels at a reasonable level, so that lithium ions can be transmitted from the secondary ion transmission channel to the primary ion transmission channel during battery charging, and then quickly transmitted from the primary ion transmission channel to the electrolytic layer, and vice versa during discharge; the present invention can construct an ordered ion transmission channel in the all-solid-state battery composite electrode, shorten the path of lithium ion transmission, reduce the tortuosity of ion transmission, and alleviate the concentration polarization in the composite electrode, so that lithium ions can be more evenly distributed along the thickness direction of the electrode, thereby enabling the all-solid-state battery composite electrode to achieve high-rate cycle performance under high mass load conditions;

[0032] (2) The method for preparing multi-level ion transport channels proposed in the present invention has wide material applicability and is simple and efficient. It does not require complex pore-making and solid electrolyte filling to construct an ion transport network. First, the porosity of the composite electrode is reduced and the ionic conductivity of the composite electrode is improved. Secondly, there is no need to consider what kind of stable and effective solvent to dissolve the solid electrolyte material, especially solid electrolyte materials such as sulfide and halide systems. In addition, a large amount of organic materials is not used, which reduces the pollution of organic chemicals to the environment and greatly reduces the complexity and cost of the preparation process. Finally, an efficient ion transport network is constructed by simple folding, rolling and winding, which greatly reduces the complexity and cost of the preparation process. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 Schematic diagram of the preparation process of an all-solid-state battery composite electrode with layered multi-level vertical ion channels according to an embodiment of the present invention;

[0034] Figure 2 Schematic diagram of the preparation process of an all-solid-state battery composite electrode with spirally distributed multi-level vertical ion channels in an embodiment of the present invention;

[0035] Figure 3 Graph showing the rate performance results of the all-solid-state batteries in Examples 1 and 6 of the present invention and Comparative Example 1;

[0036] Figure 4 This is a graph showing the rate performance results of the all-solid-state battery in Example 2 of the present invention and Comparative Example 2. DETAILED DESCRIPTION

[0037] The present invention is described in detail below with reference to specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0038] Unless otherwise specified, the equipment used in the following examples are all conventional equipment in the art; the reagents used are all commercially available products or prepared by conventional methods in the art unless otherwise specified. Anything not described in detail in the following examples can be achieved by conventional experimental means in the art.

[0039] Example 1:

[0040] An all-solid-state battery composite electrode with ordered ion transport channels and a preparation method thereof, such as Figure 1 The specific steps are as follows:

[0041] S1. 10 parts of lithium phosphorus sulfur chloride (Li6PS5Cl) and 1 part of polytetrafluoroethylene (PTFE) were fully ground and mixed in an agate mortar for 30 minutes to obtain a primary channel sheet, i.e., a primary ion transport channel serving as an ordered channel for ion transport; 70 parts of lithium cobalt oxide (LiCoO2) powder, 15 parts of Li6PS5Cl and 2 parts of vapor grown carbon fiber (VGCF) were fully ground and mixed in an agate mortar for 30 minutes, and then 2 parts of PTFE were added and fully ground and mixed for 30 minutes to obtain a secondary channel and active material sheet, i.e., a secondary ion transport channel serving as a place for electrochemical reaction;

[0042] S2. Overlapping the primary channel sheet and the secondary channel sheet with the active material sheet and rolling them together to obtain a composite sheet. The composite sheet is then folded and rolled thinned five times to obtain a block with layered multi-level ion transport channels with an average width of 50 μm.

[0043] S3, cutting the block at an angle of 90° to the primary channel sheet to obtain a block with a thickness of 100 μm and an active material surface loading of 20 mg / cm 2 A composite electrode sheet with ordered ion transport channels, with the cut surface serving as the contact surface with all-solid-state battery components;

[0044] S4. Separate the single-piece composite electrode to obtain an all-solid-state battery composite electrode with ordered ion transport channels.

[0045] The application of the above-mentioned all-solid-state battery composite electrode with ordered ion transport channels in all-solid-state batteries is as follows: composite electrode, solid electrolyte Li6PS5Cl, metal electrode lithium indium alloy (0.62V vs.Li / Li + ) are compounded in sequence to assemble an all-solid-state battery.

[0046] Example 2:

[0047] A composite electrode for an all-solid-state battery with an ordered ion transport channel and a preparation method thereof are basically the same as those in Example 1, except that in step S2, the electrode active material LiCoO2 powder is replaced with lithium iron phosphate (LiFePO4) powder, and the assembly of the all-solid-state battery is the same.

[0048] Example 3:

[0049] An all-solid-state battery composite electrode with ordered ion transport channels and a preparation method thereof, such as Figure 2 As shown, it is basically the same as Example 1, except that in step S2, the composite sheet is directly rolled and thinned so that the width of each level of ion transmission channel is 50 μm, and then wound to obtain a block with spirally distributed multi-level ion transmission channels. The assembly of the all-solid-state battery is the same.

[0050] Example 4:

[0051] A composite electrode for an all-solid-state battery with ordered ion transport channels and a preparation method thereof are basically the same as those in Example 1, except that the number of foldings in step S2 is increased from 5 to 10, so that the average width of the ion transport channels at each level is reduced from 50 μm to 25 μm, and the assembly conditions of the all-solid-state battery are the same.

[0052] Example 5:

[0053] A composite electrode for an all-solid-state battery with an ordered ion transport channel and a preparation method thereof are basically the same as those in Example 1, except that the cutting angle with the primary channel sheet in step S3 is changed from 90° to 45°, and the assembly conditions of the all-solid-state battery are the same.

[0054] Example 6:

[0055] A composite electrode for an all-solid-state battery with ordered ion transport channels and a preparation method thereof are basically the same as those in Example 1, except that the thickness of the composite electrode sheet in step S3 is increased from 100 μm to 200 μm, and the active material surface loading is increased from 20 mg / cm 2 Increased to 40mg / cm 2 , the assembly situation of all-solid-state batteries is the same.

[0056] Example 7:

[0057] A composite electrode for an all-solid-state battery with an ordered ion transport channel and a preparation method thereof. The composite electrode in Example 1 and the composite electrode in Example 4 are cross-recombined in step S4 with the cut surface as the contact surface and the ion transport channels of the two electrodes at an angle of 90° to obtain a composite electrode for an all-solid-state battery with an ordered ion transport channel. The assembly conditions of the all-solid-state battery are the same.

[0058] Example 8:

[0059] A composite electrode for an all-solid-state battery with an ordered ion transport channel and a preparation method thereof are basically the same as those in Example 1, except that the binder PTFE is replaced with polyvinylidene fluoride (PVDF) in step S1, and the assembly of the all-solid-state battery is the same.

[0060] Example 9:

[0061] A composite electrode for an all-solid-state battery with an ordered ion transport channel and a preparation method thereof are basically the same as those in Example 1, except that the electronic conductive agent VGCF is replaced with carbon black in step S1, and the assembly of the all-solid-state battery is the same.

[0062] Example 10:

[0063] A composite electrode for an all-solid-state battery with an ordered ion transport channel and a preparation method thereof are basically the same as those in Example 1, except that in step S1, the 10 parts of solid electrolyte Li6PS5Cl in the primary channel sheet are reduced to 5 parts, and the 15 parts of solid electrolyte Li6PS5Cl in the secondary channel and active material sheet are increased to 20 parts. The assembly of the all-solid-state battery is the same.

[0064] Comparative Example 1:

[0065] An all-solid-state battery composite electrode and a preparation method thereof, the specific steps are as follows:

[0066] 70 parts of LiCoO2 powder, 25 parts of Li6PS5Cl and 2 parts of VGCF were fully ground and mixed in an agate mortar for 30 minutes, and then 3 parts of PTFE were added and fully ground and mixed for 30 minutes to obtain a 100 μm thick active material surface loading of 20 mg / cm 2 The electrodes are assembled in the same way as all-solid-state batteries.

[0067] Comparative Example 2:

[0068] An all-solid-state battery composite electrode and a preparation method thereof are basically the same as those in Comparative Example 1, except that the electrode active material LiCoO2 powder is replaced with LiFePO4 powder, and the assembly of the all-solid-state battery is the same.

[0069] The above-mentioned all-solid-state battery is subjected to the following inspection or test, and then the inspection or test results are analyzed.

[0070] Test example:

[0071] The rate performance test of the all-solid-state batteries in the embodiment and the comparative example was carried out, and the specific steps are as follows:

[0072] The voltage range during the test is 2.22~4.52V vs.Li / Li + Constant current charge and discharge were performed. The discharge regime was to activate the battery at 0.1C for three cycles, then cycle at 0.3C, 0.5C, 1C and 2C for three cycles respectively, and then cycle at a rate of 0.1C. The test temperature was 35°C. The test results are shown in Table 1.

[0073] Table 1 Rate performance results of all-solid-state batteries in the examples and comparative examples

[0074]

[0075] like Figure 3As shown in Table 1, after comparing the discharge specific capacities of the all-solid-state batteries in Example 1 and Comparative Example 1 at rates of 0.1C, 0.3C, 0.5C, 1C, and 2C, it was found that the rate performance of the all-solid-state battery in Example 1 was better than that in Comparative Example 1, and as the rate increased, the gap between the two further widened, indicating that the multi-level ion transmission channel constructed by the composite electrode in the embodiment indeed reduced the tortuosity of the lithium ion conduction path, and changed the random mixing of active substances and electrolyte materials in the comparative example into a reasonable and orderly distribution of active substances and electrolyte materials, thereby reducing the tortuosity of ion transmission. This shows that the multi-level ion channel in this embodiment can improve the rate performance of the all-solid-state battery and make the ion transmission more uniform inside the composite electrode.

[0076] like Figure 4 As shown in Table 1, after comparing the discharge specific capacities of the all-solid-state batteries in Example 2 and Comparative Example 2 at rates of 0.1C, 0.3C, 0.5C, 1C, and 2C, it was found that after using LiFeO4 as the electrode active material, the rate performance of the all-solid-state battery in Example 2 was still better than that of Comparative Example 2, and also with the increase of the rate, the gap between the two further widened, which shows that the multi-level ion channels in this embodiment can improve the rate performance of the all-solid-state battery, and this method is generally applicable in all-solid-state battery composite electrodes.

[0077] As shown in Table 1, after comparing the discharge specific capacities of the all-solid-state batteries in Examples 1 and 3 at rates of 0.1C, 0.3C, 0.5C, 1C, and 2C, it was found that the simple roller-winding method in this embodiment can also enable the composite electrode to form multi-level ion transmission channels, thereby improving the rate performance of the all-solid-state battery.

[0078] As shown in Table 1, after comparing the discharge specific capacities of the all-solid-state batteries in Examples 1 and 4 at rates of 0.1C, 0.3C, 0.5C, 1C, and 2C, it was found that the discharge specific capacity of the all-solid-state battery with an ion transmission channel width of 25 μm in Example 4 at each rate was slightly inferior to that of the all-solid-state battery with an ion transmission channel width of 50 μm in Example 1, indicating that the ion transmission channel width in this embodiment has a certain influence on the rate performance of the all-solid-state battery.

[0079] As shown in Table 1, after comparing the discharge specific capacities of the all-solid-state batteries in Examples 1 and 5 at rates of 0.1C, 0.3C, 0.5C, 1C, and 2C, it was found that when the electrode cutting angle was changed from 90° in Example 1 to 45° in Example 5, the rate performance of the all-solid-state battery was improved.

[0080] like Figure 3As shown in Table 1, after comparing the discharge specific capacities of the all-solid-state batteries in Examples 1 and 6 at rates of 0.1C, 0.3C, 0.5C, 1C, and 2C, it was found that after the electrode thickness was increased from 100 μm in Example 1 to 200 μm in Example 6, the rate performance of the all-solid-state battery only decreased slightly, indicating that this embodiment can improve ion transport in thick electrodes, and when the electrode thickness in this embodiment is increased within a certain range, the all-solid-state battery can still maintain excellent rate performance under higher mass loads.

[0081] As shown in Table 1, after comparing the discharge specific capacities of the all-solid-state batteries in Examples 1 and 7 at rates of 0.1C, 0.3C, 0.5C, 1C, and 2C, it was found that the rate performance of the all-solid-state battery in Example 7 was significantly better than that in Example 1, indicating that the composite electrodes with different ion transport channel thicknesses in this embodiment are assembled in an overlapping manner, that is, an ion transport channel with a thickness gradient distribution is formed inside the composite electrode, which is beneficial to improving the ion transport inside the composite electrode and enhancing the rate performance of the all-solid-state battery.

[0082] As shown in Table 1, after comparing the discharge specific capacities of the all-solid-state batteries in Examples 1, 8, and 9 at rates of 0.1C, 0.3C, 0.5C, 1C, and 2C, it was found that the rate performance of the all-solid-state batteries in Examples 8 and 9 had slightly smaller changes than that in Example 1, indicating that in this embodiment, when the weight is constant, different types of binders and electronic conductive agents have little effect on the composite electrode.

[0083] As shown in Table 1, after comparing the discharge specific capacities of the all-solid-state batteries in Examples 1 and 10 at rates of 0.1C, 0.3C, 0.5C, 1C, and 2C, it was found that the rate performance of the all-solid-state battery in Example 10 was better than that in Example 1, indicating that in this embodiment, without affecting the preparation of the electrode, the greater the proportion of solid electrolyte in the secondary ion transport channel containing the positive electrode active material, the higher the utilization rate of the positive electrode active material, and the ion transport efficiency can be improved, thereby enhancing the rate performance of the all-solid-state battery.

[0084] The above description of the embodiments is intended to facilitate understanding and use of the invention by those skilled in the art. It will be apparent that those skilled in the art can readily make various modifications to these embodiments and apply the general principles described herein to other embodiments without requiring inventive effort. Therefore, the present invention is not limited to the above-described embodiments. Improvements and modifications made by those skilled in the art based on the disclosure of the present invention, without departing from the scope of the present invention, should be within the scope of protection of the present invention.

Claims

1. An all-solid-state battery composite electrode with ordered ion transport channels, characterized in that: The composite electrode comprises a primary ion transport channel portion and a secondary ion transport channel and active material portion, wherein the raw materials of the primary ion transport channel portion comprise 5 to 20 parts of a solid electrolyte and 0.1 to 10 parts of a binder, and the raw materials of the secondary ion transport channel and active material portion comprise 50 to 90 parts of an electrode active material, 5 to 50 parts of a solid electrolyte, 0.1 to 10 parts of an electronic conductive agent and 0.1 to 10 parts of a binder, and the mass ratio of the solid electrolyte of the primary ion transport channel portion to the solid electrolyte of the secondary ion transport channel and active material portion is (5 to 20):(5 to 50). The primary ion transport channel part and the secondary ion transport channel and the active material part are each processed into sheets by mixing raw materials, overlapping and rolling them together, repeatedly folding and rolling or roll-winding them into blocks, and cutting them into all-solid-state battery composite electrodes with ordered ion transport channels.

2. The all-solid-state battery composite electrode with ordered ion transport channels according to claim 1, characterized in that: The electrode active material is selected from one or more of lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium cobalt phosphate, lithium iron phosphate, lithium nickel cobalt manganese oxide, and lithium sulfide.

3. The all-solid-state battery composite electrode with ordered ion transport channels according to claim 1, characterized in that: The solid electrolyte is selected from one or more of a sulfide solid electrolyte, a halide solid electrolyte, and a polymer solid electrolyte; the sulfide solid electrolyte is selected from one or more of lithium phosphorus sulfur chlorine, lithium phosphorus sulfur bromine, and lithium thiophosphate; the halide solid electrolyte is selected from one or more of lithium indium chloride, lithium zinc chloride, and lithium ytterbium chloride; the polymer solid electrolyte is selected from one or more of a polyethylene oxide-based electrolyte, a polyacrylonitrile-based electrolyte, and a polyvinylidene fluoride-based electrolyte.

4. The all-solid-state battery composite electrode with ordered ion transport channels according to claim 1, characterized in that: The electronic conductive agent is selected from one or more of carbon black, carbon nanotubes, acetylene black, carbon fiber, and graphene.

5. The all-solid-state battery composite electrode with ordered ion transport channels according to claim 1, characterized in that: The binder is selected from one or more of polytetrafluoroethylene, polyethylene oxide, polyacrylonitrile, polyvinyl pyrrolidone, polyvinylidene fluoride, and cellulose.

6. A method for preparing an all-solid-state battery composite electrode having ordered ion transport channels according to any one of claims 1 to 5, characterized in that: The method comprises the following steps: S1. Mixing a solid electrolyte and a binder to obtain a primary channel sheet, and mixing an electrode active material, a solid electrolyte, an electronic conductive agent, and a binder to obtain a secondary channel and active material sheet; S2, overlapping the primary channel sheet and the secondary channel sheet with the active material sheet and rolling and compounding them to obtain a composite sheet, and then, S2.1, repeatedly folding and rolling the composite sheet to obtain a block with layered multi-level ion transport channels, or S2.

2. Rolling and thinning the composite sheet, and then winding the composite sheet to obtain a block having a spirally distributed multi-level ion transport channel; S3, cutting the block at a certain angle to the primary channel sheet to obtain a composite electrode sheet with ordered ion transport channels; S4. Separate or overlap one or more composite electrode sheets to obtain an all-solid-state battery composite electrode with ordered ion transport channels.

7. The method for preparing an all-solid-state battery composite electrode with ordered ion transport channels according to claim 6, characterized in that: The width of each level of the ion transmission channel in step S2 is 5 to 100 μm.

8. The method for preparing an all-solid-state battery composite electrode with ordered ion transport channels according to claim 6, characterized in that: In step S3, the cutting angle with respect to the primary channel sheet is 5 to 90°.

9. The method for preparing an all-solid-state battery composite electrode with ordered ion transport channels according to claim 6, characterized in that: In step S3, the thickness of the composite electrode plate is 5 to 500 μm, and the cut surface serves as the contact surface with the all-solid-state battery component.

10. The method for preparing an all-solid-state battery composite electrode with ordered ion transport channels according to claim 6, characterized in that: In step S4, when multiple composite electrode plates with the same or different structures and the same or different thicknesses are overlapped, the composite electrode plates are cross-recombined with the cut surfaces as contact surfaces and the ion transmission channels of different plates forming an angle of 0 to 90 degrees.

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