Self-repairing all-solid battery

Abstract

The application relates to the field of batteries, and discloses a self-repairing full-solid battery. A release unit containing a repairing agent is placed in a catalyst-containing epoxy resin, so that the release unit can release the repairing agent when the insulator is mechanically extruded, and the repairing agent can penetrate into the epoxy resin cracks and undergo ring-opening metathesis polymerization under the action of the catalyst, thereby generating a tough cross-linked polymer to cover the original fracture surface, and the self-repairing of the full-solid battery is promoted.

Description

Technical Field

[0001] This invention relates to the field of batteries, and more specifically to self-healing all-solid-state batteries. Background Technology

[0002] The world's growing population and significant changes in lifestyles are accelerating global energy demand. The massive consumption of fossil fuels causes environmental damage and negatively impacts climate change. Lithium-ion batteries dominate the portable electronics market, are penetrating the electric vehicle market, and are poised to enter the grid storage utility market. Among all-solid-state batteries, all-solid-state lithium-ion batteries have garnered significant attention because they use a solid electrolyte instead of a traditional liquid electrolyte, resulting in higher energy density and enhanced safety.

[0003] Generally, in the fabrication process of an all-solid-state battery stack, the negative electrode current collector layer, negative electrode active material layer, solid electrolyte layer, positive electrode active material layer, and positive electrode current collector layer are stacked in this order. In the cutting process, a cutting device with blades cuts the stack along its stacking direction. When the cut surface of the stack is viewed from a direction perpendicular to the stacking direction (hereinafter also referred to as the "width direction"), the cut surface forms a plane. In other words, the end faces of the positive electrode current collector, the positive electrode active material layer, the solid electrolyte layer, the negative electrode active material layer, and the negative electrode current collector form a generally continuous surface. On one side of the width direction, the end face of the positive electrode current collector is electrically connected to the positive electrode current collector terminal. On the opposite side of the width direction, the end face of the negative electrode current collector is electrically connected to the negative electrode current collector terminal.

[0004] However, mechanical damage caused by unexpected factors such as extrusion stress in all-solid-state battery stacks can disrupt the structural integrity and functional continuity of polymer components. Specifically, structural damage to polymers typically begins with the initial formation of micropores, followed by crack growth and propagation until these cracks reach the macroscopic level of material failure, leading to performance degradation, malfunctions, and poor stacking in all-solid-state batteries. Among existing polymer-based composite materials, self-healing methods mainly include intrinsic self-healing and exogenous self-healing, the difference being whether an external repair agent is required. Intrinsic self-healing achieves its self-healing function through the action of chemical bonds or characteristic functional groups unique to the material. This repair method can be further divided into physical self-healing and chemical self-healing based on the type of chemical bond. Intrinsic self-healing polymers can repeatedly repair themselves through the dynamic recombination of covalent or non-covalent bonds and the mixing of polymer chains at the damaged interface. Exogenous self-healing occurs when a dispersed repair agent (e.g., a mixture of monomers and polymerization initiators or catalysts) is released immediately after the ruptured reservoir is damaged due to capillary effects, repairing the damaged area through spontaneous polymerization (timely response).

[0005] However, the self-repair effect of existing all-solid-state batteries after mechanical damage is not ideal, and there is an urgent need to provide an all-solid-state battery with a highly efficient self-repair effect. Summary of the Invention

[0006] The purpose of this invention is to overcome the problem of unsatisfactory self-repair effect of existing all-solid-state batteries after mechanical damage, and to provide a self-repairing all-solid-state battery with good self-repair effect.

[0007] To achieve the above objectives, the present invention provides a self-healing all-solid-state battery, which includes at least one unit electrode body; the unit electrode body includes a positive electrode active material layer, a solid electrolyte layer and a negative electrode active material layer stacked sequentially from top to bottom, and the end of the unit electrode body is fixedly connected to an insulator.

[0008] In the unit electrode body, the ratio of the horizontal projected area of ​​the positive electrode active material layer to that of the negative electrode active material layer is 1:1-1.5;

[0009] The insulator contains an epoxy resin with a catalyst, and the epoxy resin has a built-in release unit that releases a repair agent when the insulator is subjected to mechanical compression, so as to promote the epoxy resin to react with the repair agent.

[0010] The self-healing all-solid-state battery prepared using the above technical solution incorporates a release unit containing a repair agent within a catalyst-containing epoxy resin. This release unit releases the repair agent when the insulator is subjected to mechanical compression. Under the action of the catalyst, the repair agent penetrates into the epoxy resin cracks and undergoes a ring-opening metathesis polymerization reaction, thereby generating a tough cross-linked polymer that covers the original fracture surface, promoting the self-repair of the all-solid-state battery. Therefore, the electrochemical performance and cycle performance of this all-solid-state battery are further improved. Attached Figure Description

[0011] Figure 1 This is a cross-sectional view of a self-healing all-solid-state battery involved in a specific embodiment of the present invention.

[0012] Explanation of reference numerals in the attached figures

[0013] 01 Negative electrode active material layer; 02 Solid electrolyte layer; 03 Positive electrode active material layer; 04 Negative electrode current collector layer; 05 Positive electrode current collector layer; 06 Insulating electrons; 07 Insulator; 08 Unit electrode body. Detailed Implementation

[0014] 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 and 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.

[0015] like Figure 1 As shown, the present invention provides a self-healing all-solid-state battery, which includes at least one unit electrode body 08; the unit electrode body 08 includes a positive electrode active material layer 03, a solid electrolyte layer 02 and a negative electrode active material layer 01 stacked from top to bottom, and the end of the unit electrode body is fixedly connected to an insulator 07.

[0016] In the unit electrode body 08, the horizontal projection area ratio of the positive electrode active material layer 03 to the negative electrode active material layer 01 is 1:1-1.5, preferably 1:1-1.2, for example, it can be 1:1, 1:1.1, 1:1.2 and any range between these values.

[0017] The insulator 07 includes an epoxy resin containing a catalyst, and the epoxy resin has a built-in release unit. When the insulator 07 is subjected to mechanical compression, the release unit releases a repair agent to promote a contact reaction between the epoxy resin and the repair agent.

[0018] The self-healing all-solid-state battery described in this invention promotes timely contact between the repair agent and the catalyst in the epoxy resin, thereby triggering a ring-opening metathesis polymerization reaction to generate a cross-linked polymer that covers the original fracture surface, enabling the all-solid-state battery to complete self-repair.

[0019] In this invention, when the repair agent comes into timely contact with the catalyst in the epoxy resin, the self-healing performance of the self-healing all-solid-state battery can be improved. Preferably, during the pressing of the unit electrode body 08, the all-solid-state battery is subjected to a compressive stress greater than 400 MPa, causing the release unit to release the repair agent. More preferably, the all-solid-state battery is subjected to a compressive stress greater than 600 MPa, causing the release unit to release the repair agent. For example, the compressive stress is 700-1000 MPa.

[0020] In this invention, to further improve the self-healing performance of the self-healing all-solid-state battery, preferably, the release unit is a microvascular with a circular and / or elliptical cross-section.

[0021] In this invention, preferably, the diameter of the microvascular tube with a circular cross-section is 100-300 μm, more preferably 150-250 μm.

[0022] In this invention, preferably, the major axis of the microvascular with an elliptical cross-section is 200-400 μm, more preferably 250-350 μm, and the minor axis is 100-300 μm, more preferably 150-250 μm.

[0023] In this invention, preferably, the amount of microvessels used is 6-15 wt%, more preferably 8-10 wt%, based on the total mass of the epoxy resin, for example, it can be 8 wt%, 9 wt%, 10 wt%, or any value between these values.

[0024] According to the present invention, placing the microvascular bundles in a suitable position within an insulator can improve the repair performance of the repair agent. Preferably, the vertical length of the insulator (07) is denoted by L, and the microvascular bundles are disposed from bottom to top within a range of 0.05L-0.95L within the insulator (07). More preferably, the microvascular bundles are disposed from bottom to top within a range of 0.1L-0.9L within the insulator (07).

[0025] In this invention, in order to enable the repair agent to come into contact with the catalyst in the epoxy resin in a timely manner, thereby initiating the ring-opening metathesis polymerization reaction, preferably, the microvascular tube body is perpendicular to the direction of the extrusion stress.

[0026] In this invention, to enhance the synergistic effect between the catalyst and the remedial agent, preferably, the catalyst is selected from at least one of Grubbs catalyst, WCl6, and organotin catalyst. More preferably, based on the mass of the epoxy resin, the amount of catalyst used is 1-12 wt%, preferably 2-10 wt%, for example, it can be 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%, 7 wt%, 8 wt%, 9 wt%, 10 wt%, etc., and any range between these values.

[0027] In this invention, preferably, the repair agent is selected from at least one of dicyclopentadiene, phenyl acetate, and phenylacetylene. For example, dicyclopentadiene can be used as a repair agent to contact with a Grubbs catalyst, causing a ring-opening metathesis polymerization reaction between the two to obtain polydicyclopentadiene with repair properties, thereby enabling the all-solid-state battery to complete self-repair.

[0028] In this invention, preferably, the unit electrode body 08 further includes a positive electrode current collector layer 05 disposed on the upper layer of the positive electrode active material layer 03, a negative electrode current collector layer 04 disposed on the lower layer of the negative electrode active material layer 01, and insulating electrons 06 disposed at both ends of the positive electrode current collector layer 05.

[0029] In this invention, preferably, the self-healing all-solid-state battery comprises 4-8 unit electrode bodies 08 stacked in the horizontal direction. More preferably, the self-healing all-solid-state battery comprises 4-6 unit electrode bodies 08 stacked in the horizontal direction.

[0030] In this invention, the method for preparing the catalyst-containing epoxy resin may include mixing the catalyst and the epoxy resin. Preferably, the mixing conditions include a temperature of 50-100°C and a time of 3-6 hours.

[0031] In this invention, the release unit can be a 3D microchannel network composed of multiple interconnected microvascular vessels, which can be prepared according to the method described in the literature (Toohey, Kathleen S., et al. "Self-healing materials with microvascular networks." Nature Materials 6.8 (2007): 581-585.). For example, the method of embedding the release unit in the catalyst-containing epoxy resin can be realized by direct-write assembly printing technology. Specifically: First, a fully interconnected 3D microchannel network is embedded in an epoxy resin matrix using a direct-write assembly printing device, and then a deposition process is performed to make the microchannel network layered. Second, a 3D scaffold is fabricated using volatile organic ink, and then the deposited uncured epoxy resin is impregnated into the ink scaffold and cured at room temperature for 30-50 hours. Finally, the cured product is cut to the required size and polished, then heated to 65-85°C and subjected to a slight vacuum to remove the volatile ink. Subsequently, the bottom and sides of the substrate are sealed by selectively polymerizing the photopolymer in the channel using a mercury source (λ = 365 nm) to obtain the insulator.

[0032] In this invention, the self-healing all-solid-state battery includes a positive electrode active material layer, a negative electrode active material layer, a positive electrode current collector layer, a negative electrode current collector layer, a solid electrolyte layer, an insulator, and insulating electrons. The battery can be prepared using conventional all-solid-state battery preparation methods in the art. For example, the layers are pressed and bonded sequentially in the order of positive electrode active material layer-solid electrolyte layer-negative electrode active material layer. Then, an adhesive is used to bond the positive electrode current collector layer to the positive electrode active material layer and the negative electrode current collector layer to the negative electrode active material layer to obtain a unit electrode body. Finally, the insulating electrons and the insulator are bonded to the unit electrode body using an adhesive.

[0033] In this invention, the pressing and bonding device can be selected from at least one of a flatbed press, a roller press, and a pressure die.

[0034] In this invention, the adhesive may be selected from at least one of polyamide (TPA), polyvinylidene fluoride (PVDF), and nitrile rubber (NBR). The amount of the adhesive is 3-8 wt% based on the mass of the positive electrode current collector layer; the amount of the adhesive is 3-8 wt% based on the mass of the negative electrode current collector layer.

[0035] In this invention, the adhesive may be selected from at least one of ethylene-vinyl acetate copolymer (EVA), low-density polyethylene, and polyacrylic acid. The amount of adhesive used is 2-3 wt% based on the mass of the insulating electronics; the amount of adhesive used is 2-3 wt% based on the mass of the insulator.

[0036] In this invention, the material of the positive electrode current collector layer can be at least one of aluminum, copper, nickel, iron, titanium and carbon.

[0037] In this invention, the positive electrode active material layer may include a positive electrode active material, a positive electrode conductive agent, and a binder. Preferably, the positive electrode active material may be selected from lithium cobalt oxide, lithium nickel cobalt manganese oxide (LiNiO2O3), etc. 1 / 3 Co 1 / 3 Mn 1 / 3 At least one of O2 and lithium iron phosphate. More preferably, the content of positive electrode active material in the positive electrode active material layer of the battery is 94-97 wt%.

[0038] In this invention, preferably, the positive electrode conductive agent can be selected from one or more of conductive carbon black, carbon fiber, acetylene black, Ketjen black, graphene, or carbon nanotubes. Preferably, based on the positive electrode active material, the amount of the positive electrode conductive agent can be 1-5 wt%.

[0039] According to the present invention, the positive electrode binder may be selected from one or more of polyvinylidene fluoride, polypropylene, polyethylene, polyvinylidene fluoride, vinylidene fluoride-hexafluoropropylene, polytetrafluoroethylene, or polyhexafluoropropylene. Preferably, based on the positive electrode active material, the amount of the positive electrode binder may be 1-5 wt%.

[0040] In this invention, the solid electrolyte layer can be selected from Li 0.33 La 0.56 TiO3, L i7 La3Zr2O 12 and Li 1.3 Al 0.3 Ti 1.7 At least one of (PO4)3.

[0041] In this invention, the material of the negative electrode current collector layer can be at least one of aluminum, copper, nickel, iron, titanium and carbon.

[0042] In this invention, the negative electrode active material layer may include a negative electrode active material, a negative electrode conductive agent, and a negative electrode binder. Preferably, the negative electrode active material may be selected from at least one of graphite, lithium metal, and hard carbon. More preferably, the content of the negative electrode active material in the negative electrode active material layer of the battery is 92-97 wt%.

[0043] In this invention, preferably, the negative electrode conductive agent can be selected from one or more of conductive carbon black, carbon fiber, acetylene black, Ketjen black, graphene, or carbon nanotubes. Preferably, based on the negative electrode active material, the amount of the negative electrode conductive agent can be 1-5 wt%.

[0044] According to the present invention, the negative electrode binder may be selected from one or more of polyvinylidene fluoride, polypropylene, polyethylene, polyvinylidene fluoride, vinylidene fluoride-hexafluoropropylene, polytetrafluoroethylene, or polyhexafluoropropylene. Preferably, based on the negative electrode active material, the amount of the negative electrode binder may be 1-5 wt%.

[0045] According to the present invention, the insulating electron may be selected from at least one of epoxy resin, polymethyl methacrylate and polydimethylsiloxane.

[0046] The self-healing all-solid-state battery of this invention releases a repair agent through a release unit when the insulator is subjected to mechanical compression. Under the action of a catalyst, the repair agent undergoes a ring-opening metathesis polymerization reaction, generating a tough cross-linked polymer that covers the original fracture surface, thereby improving the battery's self-healing capability. According to some preferred embodiments, the self-healing all-solid-state battery of this invention exhibits a self-healing efficiency of not less than 80% when the tensile stress is 800 MPa.

[0047] The present invention will be described in detail below through examples. In the following examples, the Grubbs catalyst was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., CAS No. 1383684-54-5, catalog number G283871; dicyclopentadiene was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., CAS No. 82-21-0, catalog number D115834; and phenyl acetate was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., CAS No. 122-79-2, catalog number P108579.

[0048] Preparation Example 1

[0049] 2 wt% of Grubbs catalyst (based on the mass of epoxy resin) was added to 15 g of epoxy resin and mixed at 60 °C for 4 h. Then, a direct-write assembly printing device (purchased from Robocasting Enterprises; Model JL2000) was used to place 10 wt% of dicyclopentadiene-filled microvessels (based on the mass of epoxy resin) into the epoxy resin containing Grubbs catalyst to prepare an insulator a1 with a length of L (L = 86 mm).

[0050] Among them, the microvessels are microvessels with a circular cross-section and a diameter of 200 μm, and are distributed from bottom to top within the range of 0.5-0.9 L of the insulator.

[0051] Preparation Example 2

[0052] 5 wt% Grubbs catalyst (based on epoxy resin mass) was added to 15 g of epoxy resin and mixed at 70 °C for 3 h. Then, a direct-write assembly printing device (purchased from Robocasting Enterprises; Model JL2000) was used to place 10 wt% of dicyclopentadiene-filled microvessels (based on epoxy resin mass) into the epoxy resin containing Grubbs catalyst to prepare an insulator a2 with a length of L (L = 86 mm).

[0053] Among them, the microvessels are microvessels with a circular cross-section and a diameter of 180 μm, and are distributed from bottom to top within the range of 0.4-0.8 L of the insulator.

[0054] Preparation Example 3

[0055] Following a method similar to that used in Preparation Example 1, except that, based on the mass of the epoxy resin, 6 wt% of microvessels infused with dicyclopentadiene were used to replace 10 wt% of microvessels infused with dicyclopentadiene to prepare insulator a3.

[0056] Preparation Example 4

[0057] Following a method similar to that used in Preparation Example 1, except that, based on the mass of the epoxy resin, 15 wt% of microvessels infused with dicyclopentadiene were used instead of 10 wt% of microvessels infused with dicyclopentadiene to prepare insulator a3.

[0058] Preparation Example 5

[0059] Following a method similar to that used in Preparation Example 1, except that, based on the mass of the epoxy resin, 1 wt% of the Grubbs catalyst was used to replace 2 wt% of the Grubbs catalyst to prepare insulator a5.

[0060] Preparation Example 6

[0061] Following a method similar to that used in Preparation Example 1, except that, based on the mass of the epoxy resin, 12 wt% of the Grubbs catalyst was used to replace 2 wt% of the Grubbs catalyst to prepare insulator a6.

[0062] Preparation Example 7

[0063] Insulator a5 was prepared by a method similar to that used in Preparation Example 1, except that phenyl acetate was used instead of dicyclopentadiene in the same weight proportions.

[0064] Example 1

[0065] Following the sequence of positive electrode active material layer - solid electrolyte layer - negative electrode active material layer, the above layers are pressed and bonded together using a pressure molding machine. Then, an adhesive is used to bond the positive electrode current collector layer to the upper layer of the positive electrode active material layer and the negative electrode current collector layer to the lower layer of the negative electrode active material layer to obtain a unit electrode body. Then, an adhesive is used to bond the insulating electrons to both ends of the positive electrode current collector layer. The insulator a1 prepared in Preparation Example 1 is bonded to both ends of the unit electrode body to prepare an all-solid-state battery A1.

[0066] The positive electrode active material layer includes: 96wt% lithium nickel cobalt manganese oxide (LiNi). 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (purchased from Ningbo Ronbay New Energy Technology Co., Ltd., grade S85E); 2 wt% conductive carbon black; 2 wt% polyvinylidene fluoride (purchased from Guangdong Jiejin Chemical Co., Ltd., grade HSV900). The negative electrode active material layer includes: 96 wt% graphite; 1 wt% conductive carbon black; 3 wt% polyvinylidene fluoride (purchased from Solvay, grade 6020); the solid electrolyte layer is LATP (lithium aluminum titanium phosphate, Li...). 1.3 Al 0.3 Ti 1.7 (PO4)3, purchased from the Scientific Materials Station, CAS No. 120479-61-0, grade FL11, item number 31090111); the positive electrode current collector layer is aluminum; the negative electrode current collector layer is copper; the insulating electrons are epoxy resin; the adhesive is polyamide (TPA, purchased from Changzhou Shanfeng Chemical Co., Ltd., grade SF-650-200); the binder is ethylene-vinyl acetate copolymer (purchased from Shanghai McLean Technology Co., Ltd., CAS No. 24937-78-8, item number P815475); and, based on the mass of the positive / negative electrode current collector layers, the amount of adhesive is 5 wt%; based on the mass of the insulating electrons, the amount of binder is 2.5 wt%; based on the mass of the insulator, the amount of binder is 2.5 wt%;

[0067] The ratio of the horizontal projected area of ​​the positive electrode active material layer to that of the negative electrode active material layer is 1:1.1.

[0068] Example 2

[0069] Following a method similar to that of Example 1, except that insulator a1 was replaced with insulator a2, an all-solid-state battery A2 was prepared.

[0070] Example 3

[0071] Following a method similar to that of Example 1, except that insulator a3 was used instead of insulator a1, an all-solid-state battery A3 was prepared.

[0072] Example 4

[0073] Following a method similar to that of Example 1, except that insulator a4 is used instead of insulator a1, an all-solid-state battery A4 is prepared.

[0074] Example 5

[0075] Following a method similar to that of Example 1, except that insulator a5 is used instead of insulator a1 to prepare an all-solid-state battery A5.

[0076] Example 6

[0077] Following a method similar to that of Example 1, except that insulator a1 is replaced with insulator a6, an all-solid-state battery A6 is prepared.

[0078] Example 7

[0079] Following a method similar to that of Example 1, except that insulator a7 is used instead of insulator a1, an all-solid-state battery A7 is prepared.

[0080] Example 8

[0081] Following a method similar to that of Example 1, the same horizontal projected area of ​​the positive electrode active material layer as in Example 1 was used, except that the ratio of the horizontal projected area of ​​the positive electrode active material layer to that of the negative electrode active material layer was 1:1.3.

[0082] Comparative Example 1

[0083] Following a method similar to that of Example 1, except that an insulator a1 containing only epoxy resin was replaced with an insulator of equal weight to obtain an all-solid-state battery B1.

[0084] Comparative Example 2

[0085] Following a method similar to that of Example 1, using the same horizontal projected area of ​​the positive electrode active material layer as in Example 1, the difference being that the ratio of the horizontal projected area of ​​the positive electrode active material layer to that of the negative electrode active material layer is 1:2, an all-solid-state battery B2 was prepared.

[0086] Test Example 1

[0087] Tensile tests were conducted on the all-solid-state batteries prepared in Examples 1-8 and Comparative Examples 1 and 2 to test their self-healing efficiency, as detailed in Table 1.

[0088] Test methods

[0089] The self-healing efficiency was evaluated based on the ability of the healing coating to restore fracture toughness: First, tensile tests were performed on the insulators in the aforementioned all-solid-state batteries at tensile stresses of 500 MPa and 800 MPa, respectively, with a four-point bending load applied to bring the insulators into a tensile state. In each loading cycle, the same crack reopened, followed by repeated healing. Second, acoustic emission sensors were placed on a crossbeam to detect crack opening events during the test. The time of the critical acoustic emission event was used to determine the load at which crack formation and reopening occurred in the original and healed sample tests. Quantitative repair testing was limited to a single crack; the loading process was stopped after the first acoustic emission signal was detected. In a few tests, new cracks did indeed appear in the coating during reloading. Samples with additional cracks were not further tested to allow for more accurate comparison of different repair cycles and samples. After testing, the insulator was allowed to heal at room temperature (25°C) for 12 hours. Any excess repair agent monomers were removed from the network by applying a slight vacuum. The network was then replenished with monomers before the next bending test. This cycle was repeated until the cracks no longer healed. According to the critical load ratio for crack opening η = P healed / P Virgin Calculate the healing efficiency for each healing cycle.

[0090] Table 1

[0091]

[0092] Test Example 2

[0093] The electrochemical and cycle performance of the all-solid-state batteries prepared in Examples 1-8 and Comparative Examples 1 and 2 were tested, and are shown in Table 2.

[0094] Test methods

[0095] (1) Specific capacity test method: The battery test system of Xinwei Company is used. The battery to be tested is installed on the test instrument and the voltage range is set to 2-4.2V. It is first activated 3 times at a current density of 0.1C, and then its rate performance is tested at different current densities.

[0096] (2) Cyclic performance test method: Install the battery to be tested on the test instrument, set the voltage range to 2-4.2V, activate it 3 times at a current density of 0.1C, and then activate it at 100mA g. -1 The battery cycle performance was then tested.

[0097] Table 2

[0098]

[0099] As can be seen from the results in Table 1, the self-healing all-solid-state battery prepared by the present invention has a self-healing efficiency of not less than 80% when the tensile stress is 800 MPa. As can be seen from the results in Table 2, compared with the comparative example, the battery prepared by the present invention has excellent specific capacity, initial coulombic efficiency and cycle performance. In particular, the batteries prepared by Examples 1 and 2 have a specific capacity of not less than 150 and a capacity retention rate of not less than 95% after 50 and 100 cycles.

[0100] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A self-healing all-solid-state battery, characterized in that, The battery includes at least one unit electrode (08); the unit electrode (08) includes a positive electrode active material layer (03), a solid electrolyte layer (02) and a negative electrode active material layer (01) stacked sequentially from top to bottom, and the end of the unit electrode is fixedly connected to an insulator (07). In the unit electrode body (08), the ratio of the horizontal projected area of ​​the positive electrode active material layer (03) to the negative electrode active material layer (01) is 1:1-1.5; The insulator (07) includes an epoxy resin containing a catalyst, and the epoxy resin has a built-in release unit that releases a repair agent when the insulator (07) is subjected to mechanical extrusion, so as to promote the epoxy resin to react with the repair agent.

2. The self-healing all-solid-state battery according to claim 1, wherein, When the unit electrode body (08) is pressed, the all-solid battery is subjected to compressive stress greater than 400 MPa, causing the release unit to release the repair agent; Preferably, the all-solid-state battery is subjected to compressive stress greater than 600 MPa, causing the release unit to release the repair agent.

3. The self-healing all-solid-state battery according to claim 1 or 2, wherein, The release unit is a microvascular tube with a circular and / or elliptical cross-section; Preferably, the diameter of the microvessel with a circular cross-section is 100-300 μm; Preferably, the microvascular tube with an elliptical cross-section has a major axis length of 200-400 μm and a minor axis length of 100-300 μm.

4. The self-healing all-solid-state battery according to any one of claims 1-3, wherein, More preferably, based on the total mass of the epoxy resin, the amount of the microvessels is 6-15 wt%, preferably 8-10 wt%.

5. The self-healing all-solid-state battery according to any one of claims 1-4, wherein, The vertical length of the insulator (07) is denoted as L, and the micro-pulses are arranged from bottom to top within the range of 0.05L-0.95L of the insulator (07).

6. The self-healing all-solid-state battery according to any one of claims 1-5, wherein, The microvascular tube is perpendicular to the direction of the compressive stress.

7. The self-healing all-solid-state battery according to any one of claims 1-6, wherein, The catalyst is selected from at least one of Grubbs catalyst, WCl6 catalyst and organotin catalyst; Preferably, the amount of catalyst used is 1-12 wt%, more preferably 2-10 wt%, based on the mass of the epoxy resin.

8. The self-healing all-solid-state battery according to any one of claims 1-7, wherein, The repair agent is selected from at least one of dicyclopentadiene, phenyl acetate, and phenylacetylene.

9. The self-healing all-solid-state battery according to any one of claims 1-8, wherein, The unit electrode body (08) further includes a positive electrode current collector layer (05) disposed on the upper layer of the positive electrode active material layer (03), a negative electrode current collector layer (04) disposed on the lower layer of the negative electrode active material layer (01), and insulating electrons (06) disposed at both ends of the positive electrode current collector layer (05).

10. The self-healing all-solid-state battery according to any one of claims 1-9, wherein, The battery comprises 4-8 unit electrodes stacked in the horizontal direction (08); Preferably, the battery includes 4-6 unit electrode bodies (08) stacked in the horizontal direction.

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