Preparation method of semi-solid-state battery, battery and device thereof, and power utilization and energy storage device

Abstract

The embodiment of the invention relates to the field of energy storage, and provides a preparation method of a semi-solid battery, the battery and a device thereof, and a power utilization and energy storage device, the method comprises the following steps: adding hexagonal boron nitride into a solvent to obtain a first mixed solution; adding a coupling agent into the first mixed solution to obtain a second mixed solution; performing ultrasonic dispersion treatment on the second mixed solution to obtain a dispersion solution; mixing an elastomer network monomer, a diluent, a thermal initiator and an electrolyte to obtain a third mixed solution; adding the dispersion liquid into the third mixed liquid to obtain a precursor solution; and injecting the precursor solution into a battery, and carrying out curing treatment on the battery to obtain the semi-solid battery. The semi-solid-state battery provided by the embodiment of the invention at least can improve the safety performance of the energy storage battery.

Description

Technical Field

[0001] This application relates to the field of energy storage, and in particular to a method for preparing a semi-solid battery, a semi-solid battery, a battery device, an electrical device, and an energy storage device. Background Technology

[0002] Existing semi-solid batteries use gel electrolytes with low thermal conductivity, making it difficult to conduct heat in a timely manner and posing a high risk of thermal runaway. Summary of the Invention

[0003] This application provides a method for preparing a semi-solid-state battery, a semi-solid-state battery, a battery device, an electrical device, and an energy storage device, which at least helps to reduce the risk of thermal runaway of semi-solid-state batteries.

[0004] According to some embodiments of this application, one aspect of this application provides a method for preparing a semi-solid-state battery, comprising: adding hexagonal boron nitride to a solvent to obtain a first mixture; adding a coupling agent to the first mixture to obtain a second mixture; subjecting the second mixture to ultrasonic dispersion treatment to obtain a dispersion; mixing an elastomer network monomer, a diluent, a thermal initiator, and an electrolyte to obtain a third mixture; adding the dispersion to the third mixture to obtain a precursor solution; injecting the precursor solution into a battery and subjecting the battery to a curing treatment to obtain the semi-solid-state battery.

[0005] In some embodiments, after adding hexagonal boron nitride to the solvent, the method further includes adding a nanofiller to the solvent, the nanofiller comprising Al2O3 and / or SiO2, wherein the particle size of Al2O3 is 1-100 nm, the particle size of SiO2 is 1-100 nm, and the mass of the nanofiller accounts for 0-5% of the mass of the precursor solution.

[0006] In some embodiments, the battery is cured by placing it in an ambient heating device at a preset ambient temperature for a preset time to allow the precursor solution to form a gel electrolyte. The preset ambient temperature is 60-70°C and the preset time is 2-4 hours.

[0007] In some embodiments, the hexagonal boron nitride has a sheet diameter of 0.5-5 μm and a thickness of 30-100 nm.

[0008] In some embodiments, the coupling agent is a silane coupling agent, including KH-550.

[0009] In some embodiments, the amount of coupling agent added is 1% to 3% of the mass of the hexagonal boron nitride.

[0010] In some embodiments, the elastomeric network monomer comprises at least one of polyurethane acrylate or acrylic acid-terminated polysiloxane, and the mass of the elastomeric network monomer accounts for 4-10% of the mass of the precursor solution.

[0011] In some embodiments, the diluent comprises polyethylene glycol diacrylate having a number-average molecular weight of 400-700.

[0012] In some embodiments, the diluent accounts for 3-5% of the mass of the precursor solution.

[0013] In some embodiments, the thermal initiator includes azobisisobutyronitrile (AIBN).

[0014] In some embodiments, the hexagonal boron nitride accounts for 5-15% of the mass of the precursor solution.

[0015] In some embodiments, the electrolyte comprises a lithium salt and an organic solvent, wherein the lithium salt comprises lithium hexafluorophosphate, and the organic solvent comprises ethylene carbonate (EC), diethyl carbonate (DEC), and dimethyl carbonate (DMC), wherein the volume ratio of ethylene carbonate, diethyl carbonate, and dimethyl carbonate is 1:1:1.

[0016] According to some embodiments of this application, another aspect of this application provides a semi-solid-state battery, which is prepared by any of the methods described for preparing a semi-solid-state battery.

[0017] According to some embodiments of this application, another aspect of this application provides a battery device, including any of the aforementioned semi-solid-state batteries, wherein the battery device includes one or more of a battery module, a battery pack, and an energy storage battery.

[0018] According to some embodiments of this application, in another aspect, this application provides an electrical device, the electrical device including any of the battery devices described above, the battery device being used to provide electrical energy.

[0019] According to some embodiments of this application, another aspect of this application provides an energy storage device, the energy storage device including any of the battery devices described above, the battery device being used to store electrical energy.

[0020] The technical solution provided in this application has at least the following advantages: In this application, hexagonal boron nitride filler with a coupling agent is used in the precursor solution, which makes the hexagonal boron nitride more uniformly dispersed in the system and forms a stable interface bond with the gel network during the in-situ gelation process. Since hexagonal boron nitride has high thermal conductivity and is more likely to form continuous or near-continuous heat transfer paths in the gel system after surface treatment, the overall thermal conductivity of the gel electrolyte obtained after curing is improved. Heat generated during battery operation or abnormal conditions can be diffused and conducted more quickly inside the battery, reducing local heat accumulation and temperature rise, thereby reducing the risk of thermal runaway and improving the safety of the semi-solid-state battery. Attached Figure Description

[0021] One or more embodiments are illustrated by way of example with reference to the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Unless otherwise stated, the drawings in the accompanying drawings do not constitute a limitation on scale. In order to more clearly illustrate the technical solutions in the embodiments of this application or in the conventional art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 A schematic flowchart of a method for preparing a semi-solid-state battery according to an embodiment of this application is shown. Detailed Implementation

[0023] As is known from the background art, the gel electrolyte used in the prior art semi-solid batteries has low thermal conductivity, which makes it difficult to conduct heat in a timely manner and results in a high risk of thermal runaway. In order to solve the above technical problems, the embodiments of this application provide a method for preparing a semi-solid battery, a semi-solid battery, a battery device, an electrical device, and an energy storage device.

[0024] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0025] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0026] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent three cases: A exists, A and B exist simultaneously, and B exists. In addition, the character " / " in this document generally indicates that the related objects before and after it have an "or" relationship.

[0027] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0028] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0029] In the description of the embodiments of this application, unless otherwise expressly specified and limited, the technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0030] In the accompanying drawings corresponding to the embodiments of this application, the thickness and area of ​​the layers are enlarged for better understanding and ease of description. When describing a component (such as a layer, film, region, or substrate) on or on the surface of another component, the component may be "directly" located on the surface of the other component, or there may be a third component between the two components. Conversely, when describing a component on the surface of another component, or when another component is formed or disposed on the surface of a component, it indicates that there is no third component between the two components. Furthermore, when describing a component as being "generally" formed on another component, it means that the component is not formed on the entire surface (or front surface) of the other component, nor is it formed on a portion of the edge of the entire surface.

[0031] In the description of the embodiments of this application, when a component "includes" another component, other components are not excluded unless otherwise stated, and other components may be further included. Furthermore, when a component such as a layer, film, region, or plate is referred to as being "on / located" on another component, it can be "directly on" the other component (i.e., located on the surface of the other component with no other components between them), or another component may be present therein. Moreover, when a component such as a layer, film, region, or plate is "directly located" on another component, or when a component such as a layer, film, region, or plate is located on the surface of another component, it indicates that no other components are located therein.

[0032] The terminology used in the description of the various embodiments described herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used in the description of the various embodiments and the appended claims, the term "foreword" is also intended to include the plural form unless the context clearly indicates otherwise. Components include layers, films, regions, or plates, etc.

[0033] The embodiments of this application will now be described in detail with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been provided in the embodiments of this application to facilitate a better understanding of the application. However, the technical solutions claimed in this application can be implemented even without these technical details and various variations and modifications based on the following embodiments.

[0034] This embodiment provides a method for preparing a semi-solid-state battery, such as... Figure 1 As shown, it includes:

[0035] Step S101: Add hexagonal boron nitride to the organic solvent used for dispersion, stir to initially wet it and form a dispersion system, and obtain a first mixed solution containing hexagonal boron nitride.

[0036] Specifically, organic solvents are used to provide a good dispersion environment for hexagonal boron nitride. For example, anhydrous ethanol can be used to reduce the impact of moisture in the system on subsequent reactions and battery performance.

[0037] Step S102: Add coupling agent to the first mixture and continue stirring to ensure that the coupling agent and hexagonal boron nitride are in full contact to obtain the second mixture.

[0038] Specifically, the coupling agent preferentially adsorbs onto the surface of hexagonal boron nitride and reacts with its functional groups such as hydroxyl groups to improve its dispersibility and compatibility in the system.

[0039] Step S103: The second mixture is subjected to ultrasonic dispersion treatment to obtain a dispersion.

[0040] Specifically, the second mixture is subjected to ultrasonic treatment in an ultrasonic cleaner or a probe-type ultrasonic processor. Optionally, the ultrasonic treatment time is not less than 30 minutes. The cavitation effect generated by ultrasound allows the stacked hexagonal boron nitride sheets to be peeled off and their aggregation reduced. Simultaneously, the exposed sheet surfaces during ultrasonic peeling can promptly contact and coat the coupling agent molecules, thereby inhibiting the re-aggregation of hexagonal boron nitride through steric hindrance and surface energy regulation, ultimately resulting in a uniformly dispersed and stable milky white suspension.

[0041] Step S104: In another container, the elastomer network monomers used to construct the gel network, the diluent used to adjust the viscosity of the system, the thermal initiator and the electrolyte are mixed to obtain a third mixture for subsequent injection.

[0042] Specifically, the third mixed solution can undergo a polymerization reaction under heating conditions to form a stable gel electrolyte structure.

[0043] Step S105: Add the dispersion to the third mixture to obtain the precursor solution;

[0044] In step S106, the precursor solution is injected into the battery and the battery is solidified to obtain a semi-solid battery.

[0045] Specifically, a precursor solution is injected into a battery with assembled electrodes, and the battery is heated after the injection is complete and the electrolyte is fully wetted. Heating initiates a polymerization reaction in the precursor solution, causing it to form a gel electrolyte in situ inside the battery, thus obtaining a semi-solid-state battery.

[0046] In the process of preparing the first mixture, the second mixture, and the dispersion, the solution mixing and ultrasonic dispersion operations are all completed in a borosilicate glass bottle with a PTFE (polytetrafluoroethylene) liner.

[0047] In the above embodiments, hexagonal boron nitride filler with a surface-coupling agent is used in the precursor solution to make the hexagonal boron nitride more uniformly dispersed in the system and to form a stable interfacial bond with the gel network during the in-situ gelation process. Because hexagonal boron nitride has high thermal conductivity and, after surface treatment, can more easily form continuous or near-continuous heat transfer paths in the gel system, the overall thermal conductivity of the gel electrolyte obtained after curing is improved. Heat generated during battery operation or under abnormal conditions can diffuse and conduct more quickly within the battery, reducing local heat accumulation and temperature rise, thereby reducing the risk of thermal runaway and improving the safety of the semi-solid-state battery.

[0048] In one alternative approach, after adding hexagonal boron nitride to the solvent, a nanofiller is added to the solvent for co-dispersion. The nanofiller comprises Al₂O₃ and / or SiO₂, with Al₂O₃ having a particle size of 1-100 nm and SiO₂ having a particle size of 1-100 nm. The mass of the nanofiller accounts for 0-5% of the mass of the precursor solution, and the nanofiller content is greater than 0%. By introducing the nanofiller during the dispersion stage, the dispersion stability and structural compactness of the system are improved. Furthermore, by controlling the amount of nanofiller added, the mechanical strength and structural stability of the gel electrolyte are effectively enhanced without significantly affecting the ion transport performance.

[0049] Optionally, the mass of the nanofiller may account for 1%, 2%, 3%, 4% or 5% of the total mass of the precursor solution, or other values ​​within the above range. This embodiment does not limit this.

[0050] Preferably, the mass of the nanofiller accounts for a certain percentage of the mass of the precursor solution.

[0051] Optionally, the particle size of Al2O3 can be 1 nm, 10 nm, 20 nm, 50 nm or 100 nm.

[0052] Preferably, the particle size of Al2O3 is 20nm, 30nm, or 40nm.

[0053] Optionally, the particle size of SiO2 can be 1 nm, 10 nm, 20 nm, 50 nm or 100 nm, or other values ​​within the above range. This embodiment does not limit this.

[0054] Preferably, the particle size of SiO2 is 10nm, 20nm, or 30nm.

[0055] In one specific embodiment, the nanofiller is selected from Al2O3 nanoparticles with a particle size of 20-50 nm, and its addition amount is 1% of the total mass of the precursor solution.

[0056] In another specific embodiment, the nanofiller is selected as SiO2 nanoparticles with a particle size of 30-80 nm, and its addition amount is 2% of the total mass of the precursor solution.

[0057] In another specific embodiment, the nanofiller is a composite nanofiller of Al2O3 and SiO2, wherein the total amount of Al2O3 and SiO2 added is 3% of the total mass of the precursor solution.

[0058] It should be noted that the nanofiller is an optional component, used to further optimize the dispersion stability and structural properties of the system. In some embodiments, the nanofiller may not be added.

[0059] In another optional approach, the battery undergoes a curing process, including placing the battery in an ambient heating device at a preset temperature for a preset time to allow the precursor solution to form a gel electrolyte. The preset ambient temperature is 60-70°C, and the preset time is 2-4 hours. By curing at the preset temperature for the preset time, the precursor solution is fully gelled in situ to form a gel electrolyte, thereby improving the consistency of gel formation and the stability and safety of the battery.

[0060] Specifically, the environmental heating device includes an oven, a constant temperature chamber, a forced-air drying oven, a vacuum oven, or other devices that can provide a stable heating environment.

[0061] Optionally, the ambient temperature can be 60°C, 62°C, 65°C, 68°C or 70°C, or other values ​​within the above range. This embodiment does not limit this.

[0062] Preferably, the ambient temperature is 65°C.

[0063] Optionally, the curing time can be 2 h, 2.5 h, 3 h, 3.5 h or 4 h, or other values ​​within the above range. This embodiment does not limit this.

[0064] Preferably, the curing time is 3 hours.

[0065] In one specific embodiment, the battery, which has been injected with the precursor solution and completed the wetting process, is placed in an oven and placed at 65°C for 3 hours to complete the curing and form a gel electrolyte.

[0066] In another specific embodiment, the battery is placed in a forced-air drying oven and placed at 60°C for 4 hours to complete curing and form a gel electrolyte.

[0067] In another specific embodiment, the battery is placed in a constant temperature chamber and placed at 70°C for 2 hours to complete the curing and form a gel electrolyte.

[0068] In some exemplary embodiments, the hexagonal boron nitride has a sheet diameter of 0.5-5 μm and a thickness of 30-100 nm. Limiting the sheet diameter range of hexagonal boron nitride facilitates the formation of continuous and stable thermally conductive pathways in the gel electrolyte, thereby improving thermal conductivity and heat dissipation performance of the battery. Limiting the thickness range of hexagonal boron nitride enhances its dispersibility and interfacial bonding within the system, which is beneficial for forming a stable thermally conductive network.

[0069] Optionally, the diameter of the hexagonal boron nitride sheet can be 0.5μm, 1μm, 2μm, 3μm, 4μm or 5μm, or other values ​​within the above range. This embodiment does not limit this.

[0070] Preferably, the diameter of the hexagonal boron nitride flake is 2 or 3 μm.

[0071] Optionally, the thickness of the hexagonal boron nitride can be 30 nm, 40 nm, 50 nm, 70 nm or 100 nm, or other values ​​within the above range. This embodiment does not limit this.

[0072] Preferably, the thickness of the hexagonal boron nitride is 50 or 70 nm.

[0073] In one specific embodiment, the hexagonal boron nitride is selected as a sheet-like hexagonal boron nitride with a diameter of 2-3 μm and a thickness of 50-70 nm.

[0074] In another specific embodiment, hexagonal boron nitride is selected from hexagonal boron nitride sheets with a diameter of 1-4 μm and a thickness of 40-80 nm.

[0075] In some other exemplary embodiments, the coupling agent is a silane coupling agent, including KH-550.

[0076] In the above embodiments, the surface treatment of hexagonal boron nitride with a silane coupling agent is beneficial to the uniform distribution of hexagonal boron nitride in the gel electrolyte, thereby helping to improve the thermal conductivity of the gel electrolyte.

[0077] Specifically, silane coupling agents also include KH-570.

[0078] In some exemplary embodiments of this application, the amount of coupling agent added is 1% to 3% of the mass of hexagonal boron nitride.

[0079] In the above embodiments, by limiting the amount of coupling agent added, it is possible to ensure the surface modification effect while avoiding excessive introduction that would have an adverse effect on the system performance, which is beneficial to the stable dispersion of hexagonal boron nitride in the precursor system.

[0080] In some further exemplary embodiments of this application, the elastomeric network monomer includes at least one of polyurethane acrylate or acrylic acid-terminated polysiloxane, and the mass of the elastomeric network monomer accounts for 4-10% of the mass of the precursor solution. Using polyurethane acrylate and / or acrylic acid-terminated polysiloxane as the elastomeric network monomer, and controlling its mass percentage to 4-10% of the precursor solution, is beneficial for forming a polymer network skeleton with a certain degree of elasticity during the curing process. This improves the toughness and morphological stability of the gel electrolyte, enhances its interfacial adhesion with the electrodes and separator, and helps maintain the ion transport performance of the battery while ensuring structural stability.

[0081] Optionally, the mass of the elastomer network monomer may account for 4%, 5%, 6%, 7%, 8%, 9% or 10% of the total mass of the precursor solution, or other values ​​within the above range. This embodiment does not limit this.

[0082] Preferably, the mass of the elastomer network monomer accounts for 6.8% of the total mass of the precursor solution.

[0083] Optionally, the elastomer network monomer may include only polyurethane acrylate, or only acrylic-terminated polysiloxane, or a combination of polyurethane acrylate and acrylic-terminated polysiloxane. This embodiment does not limit this.

[0084] Preferably, the elastomer network monomer comprises a combination of polyurethane acrylate and acrylic-terminated polysiloxane to balance the mechanical strength and flexibility of the gel electrolyte.

[0085] In one specific embodiment, the elastomer network monomer is selected as polyurethane acrylate, and its addition amount is 6% of the total mass of the precursor solution.

[0086] In another specific embodiment, the elastomer network monomer is selected as acrylic acid-terminated polysiloxane, and its addition amount is 5% of the total mass of the precursor solution.

[0087] In another specific embodiment, the elastomer network monomer is a combination of polyurethane acrylate and acrylic acid-terminated polysiloxane, wherein the total amount of both added is 7% of the total mass of the precursor solution.

[0088] In one alternative, the diluent includes polyethylene glycol diacrylate with a number-average molecular weight of 400-700. Using polyethylene glycol diacrylate with a number-average molecular weight of 400-700 as a diluent helps adjust the viscosity of the precursor solution and improve the system's liquid-feedability. Simultaneously, it participates in the formation of a polymer network during the curing process, introducing flexible polyether segments, thereby contributing to improved flexibility and structural stability of the gel electrolyte and maintaining ion transport properties.

[0089] In some exemplary embodiments, the diluent is used to adjust the viscosity of the precursor solution and improve its injectability, and may participate in the formation of a gel network during the curing process. The diluent is not limited to polyethylene glycol diacrylate, but may also be one or more of acrylate or methacrylate reactive diluents, or polyether diluents.

[0090] Optionally, the number average molecular weight of polyethylene glycol diacrylate can be 400, 450, 500, 600 or 700, or other values ​​within the above range. This embodiment does not limit this.

[0091] Preferably, the number average molecular weight of polyethylene glycol diacrylate is 500 or 600.

[0092] In one specific embodiment, the diluent is polyethylene glycol diacrylate with a number average molecular weight of 500, which can effectively reduce the viscosity of the system in the precursor solution and form a gel electrolyte structure with good flexibility after curing.

[0093] In another specific embodiment, polyethylene glycol diacrylate with a number average molecular weight of 600 is selected as the diluent to improve the structural stability and ion transport continuity of the gel electrolyte while ensuring the fluidity of the precursor solution.

[0094] In another alternative, the diluent accounts for 3-5% of the precursor solution's mass. By controlling the diluent content, it is beneficial to improve flowability and gel uniformity while avoiding adverse effects on ion transport performance.

[0095] Optionally, the mass of the diluent may be 3%, 4% or 5% of the total mass of the precursor solution, or other values ​​within the above range. This embodiment does not limit this.

[0096] Preferably, the diluent accounts for 4% of the total mass of the precursor solution.

[0097] In one specific embodiment, the amount of diluent added is 4% of the total mass of the precursor solution.

[0098] In another specific embodiment, the amount of diluent added is 3.5% of the total mass of the precursor solution.

[0099] In some exemplary embodiments, the thermal initiator includes azobisisobutyronitrile (AIBN).

[0100] Other thermal initiators that can generate free radicals and initiate monomer polymerization reactions under heating conditions can also be selected, such as peroxide initiators or other azo initiators. By selecting a suitable thermal initiator, a stable and controllable polymerization reaction can be achieved within a preset heating temperature range, thereby promoting the uniform gelation of the precursor solution inside the battery.

[0101] In the above embodiments, azobisisobutyronitrile (AIBN) is used as a thermal initiator, which can stably decompose and generate free radicals within a preset temperature range. This is beneficial for the uniform polymerization reaction in the precursor solution, thereby improving the stability of the gel electrolyte gelation process.

[0102] In other exemplary embodiments, the mass of hexagonal boron nitride accounts for 5-15% of the mass of the precursor solution. By controlling the mass ratio of hexagonal boron nitride in the precursor solution, it is beneficial to form an effective heat transfer pathway in the gel electrolyte, thereby improving the thermal conductivity of the gel electrolyte and promoting heat conduction inside the battery.

[0103] Optionally, the mass of hexagonal boron nitride may account for 5%, 7%, 10%, 12% or 15% of the total mass of the precursor solution, or other values ​​within the above range. This embodiment does not limit this.

[0104] Preferably, the mass of hexagonal boron nitride accounts for 10% to 12% of the total mass of the precursor solution.

[0105] In one specific embodiment, the amount of hexagonal boron nitride added is 6% of the total mass of the precursor solution.

[0106] In another specific embodiment, the amount of hexagonal boron nitride added is 11% of the total mass of the precursor solution, in order to balance the thermal conductivity of the gel electrolyte with the dispersion stability of the system.

[0107] In some exemplary embodiments of this application, the electrolyte includes a lithium salt and an organic solvent. The lithium salt includes lithium hexafluorophosphate, and the organic solvent includes ethylene carbonate (EC), diethyl carbonate (DEC), and dimethyl carbonate (DMC). The volume ratio of ethylene carbonate, diethyl carbonate, and dimethyl carbonate is 1:1:1.

[0108] The electrolyte provides ion conduction channels for the battery. The lithium salt provides the transportable lithium ions in the organic solvent; alternatively, lithium perchlorate (LiClO4), lithium tetrafluoroborate (LiBF4), lithium bis(fluorosulfonyl)imide (LiFSI), etc., can be selected. The organic solvent, acting as a solvent for the lithium salt, dissolves the lithium salt and constructs a continuous phase for the electrolyte. In other embodiments, the organic solvent may also include one or more of propylene carbonate (PC), ethyl methyl carbonate (EMC), etc., and the selected solvents can be combined as needed.

[0109] In the above embodiments, the use of an organic solvent system ensures that the electrolyte has good ionic conductivity and wettability to the electrodes.

[0110] An embodiment of this application also provides a semi-solid battery, which is prepared by any of the above-described methods for preparing semi-solid batteries.

[0111] In the above embodiments, the semi-solid battery prepared by any of the above preparation methods can obtain a stable electrolyte structure with gel electrolyte, which is beneficial to improving the thermal safety of the battery and reducing the risk of thermal runaway.

[0112] An embodiment of this application further provides a battery device, including any of the above-mentioned semi-solid-state batteries, wherein the battery device includes one or more of a battery module, a battery pack, and an energy storage battery.

[0113] In the above embodiments, the battery device can achieve the thermal safety improvement effect brought by semi-solid batteries, thereby helping to reduce the risk of thermal runaway during use and improve overall safety.

[0114] An embodiment of this application provides an electrical device, which includes any of the above-described battery devices, the battery devices being used to provide electrical energy.

[0115] In the above embodiments, after the precursor solution is injected into the semi-solid battery in the battery device, the precursor solution is heated to induce polymerization inside the battery and form a gel electrolyte. The thermally conductive pathways formed in the gel electrolyte promote the conduction and diffusion of heat inside the battery, reduce heat accumulation, thereby helping to reduce the risk of thermal runaway and improve the safety of the battery device and the electrical device.

[0116] An embodiment of this application also provides an energy storage device, which includes any of the above-described battery devices, the battery devices being used to store electrical energy.

[0117] In the above embodiments, the semi-solid battery in the battery device uses a gel electrolyte, which is beneficial for the conduction and diffusion of heat inside the battery and reduces heat accumulation, thereby helping to improve the safety of the energy storage device during operation and reduce the risk of thermal runaway.

[0118] This embodiment provides a specific method for preparing a semi-solid-state battery, including:

[0119] Step S1: Pretreatment step: Ensure that all containers and inorganic packing materials are completely dried in a vacuum oven (100℃ for 12h) to remove adsorbed water.

[0120] Step S2: Prepare a hexagonal boron nitride pre-dispersed suspension;

[0121] Step S21: Mixing: In a high borosilicate bottle with a polytetrafluoroethylene liner, take an appropriate amount of anhydrous ethanol and add the calculated amount of hexagonal boron nitride powder.

[0122] Step S22: Surface modification: Add 1% by mass of KH-550 coupling agent of hexagonal boron nitride and stir evenly. The coupling agent preferentially adsorbs and reacts with functional groups such as hydroxyl groups on the surface of hexagonal boron nitride.

[0123] Step S23: Ultrasonic Dispersion: Place the mixture in a high-power ultrasonic cleaner or a probe-type ultrasonic processor and treat for at least 30 minutes. Specifically, the cavitation effect of ultrasound can strongly open the stacked hexagonal boron nitride sheets, and the newly exposed surfaces are immediately coated with coupling agent molecules, preventing them from re-aggregating through steric hindrance and changes in surface energy. Continue until a uniform and stable milky white suspension is formed.

[0124] Step S24: Perform multiple filtrations (at least 3 times) with anhydrous ethanol to ensure that all soluble impurities (unreacted coupling agents, self-polymerizing oligomers, and reaction solvents) are completely washed away. The cleaned, modified filler powder is then dried again in a 60°C vacuum oven for 24 hours.

[0125] Step S3: Mixing of the main system and in-situ thermal polymerization;

[0126] Step S31: Preparation of the main system: In another container, the elastomer network monomer, reactive diluent (PEGDA), thermal initiator (AIBN) and electrolyte are mixed evenly. The elastomer network monomer is at least one of polyurethane acrylate (PUA) and acrylic end-capped polysiloxane (PDMS-MA).

[0127] Step S32: Composite: Under gentle stirring, the hexagonal boron nitride powder prepared in the first step is slowly added to the main system, and stirring is continued for 60 minutes to ensure that the two phases are mixed evenly, so as to obtain the final injection precursor solution.

[0128] Step S33: Electrolyte Injection and Polymerization: 16g of the precursor solution is injected into the assembled 4Ah soft-pack dry cell. After soaking, the cell is left to stand at room temperature for 24 hours, followed by formation, degassing, and aging. The aging temperature is 40℃, and the aging time is 36 hours. The battery is then placed in an oven at 60-70℃ and heated for 2-4 hours to initiate the decomposition of azobisisobutyronitrile (AIBN) and complete in-situ polymerization. Finally, after conventional capacity testing, the final high thermal conductivity gel electrolyte cell is obtained.

[0129] The preparation process of the dry cell includes: mixing the positive electrode active material lithium iron phosphate, conductive carbon black, carbon nanotubes (CNTs), and binder polyvinylidene fluoride (PVDF) in a mass ratio of 96.8%:0.8%:0.4%:2% to obtain a mixed material; and thoroughly stirring the mixed material in N-methylpyrrolidone (NMP) to obtain the corresponding positive electrode slurry. The negative electrode active material artificial graphite, conductive carbon black (Super-P Li), dispersant sodium carboxymethyl cellulose (CMC), binder polyacrylic acid (PAA), and binder styrene-butadiene rubber (SBR) in a mass ratio of 95.8%:1%:0.8%:1.2%:1.2% to obtain a mixed material; and thoroughly stirring the mixed material in deionized water to obtain the corresponding negative electrode slurry. After stirring and slurry preparation, the positive electrode slurry and negative electrode slurry are coated onto 11μm thick aluminum foil and 5μm thick copper foil, respectively. After drying, they are processed into 4Ah soft-pack battery cells through processes such as rolling, cutting, slitting, and winding.

[0130] The preparation method of the semi-solid battery of this application will be described in detail below with reference to specific embodiments and comparative examples.

[0131] Example 1

[0132] This application provides a method for preparing a semi-solid-state battery, comprising:

[0133] Hexagonal boron nitride was added to a solvent to obtain a first mixture, wherein the mass of hexagonal boron nitride accounted for 5% of the mass of the precursor solution;

[0134] A coupling agent is added to the first mixture to obtain a second mixture, wherein the amount of coupling agent added is 1% of the mass of hexagonal boron nitride;

[0135] The second mixture was subjected to ultrasonic dispersion treatment to obtain a dispersion.

[0136] The elastomer network monomer, diluent, thermal initiator, and electrolyte are mixed to obtain a third mixture, wherein the mass of the elastomer network monomer accounts for 4% of the mass of the precursor solution, and the mass of the diluent accounts for 3% of the mass of the precursor solution.

[0137] The dispersion was added to the third mixture to obtain the precursor solution;

[0138] The precursor solution is injected into the battery, and the battery is then solidified to obtain a semi-solid battery.

[0139] Example 2

[0140] This application provides a method for preparing a semi-solid battery. The difference between this embodiment and Embodiment 1 is that the mass of hexagonal boron nitride accounts for 15% of the mass of the precursor solution.

[0141] Example 3

[0142] This application provides a method for preparing a semi-solid battery. The difference between this embodiment and Embodiment 2 is that the mass of hexagonal boron nitride accounts for 7% of the mass of the precursor solution.

[0143] Example 4

[0144] This application provides a method for preparing a semi-solid battery. The difference between this embodiment and Embodiment 1 is that the mass of the diluent accounts for 5% of the mass of the precursor solution.

[0145] Example 5

[0146] This application provides a method for preparing a semi-solid battery. The difference between this embodiment and Embodiment 4 is that the mass of the diluent accounts for 3% of the mass of the precursor solution.

[0147] Example 6

[0148] This application provides a method for preparing a semi-solid battery. The difference between this embodiment and Embodiment 1 is that the mass of the elastomer network monomer accounts for 10% of the mass of the precursor solution.

[0149] Example 7

[0150] This application provides a method for preparing a semi-solid battery. The difference between this embodiment and Embodiment 6 is that the mass of the elastomer network monomer accounts for 6% of the mass of the precursor solution.

[0151] Example 8

[0152] The difference from Example 1 is that the amount of coupling agent added is 3% of the mass of hexagonal boron nitride.

[0153] Example 9

[0154] The difference from Example 8 is that the amount of coupling agent added is 2% of the mass of hexagonal boron nitride.

[0155] Example 10

[0156] The difference from Example 1 is that nanofillers are added to the solvent, and the amount added is 5% of the mass of the precursor solution.

[0157] Example 11

[0158] The difference from Example 1 is that nanofillers are added to the solvent, and the amount added is 2% of the mass of the precursor solution.

[0159] Comparative Example 1

[0160] A method for preparing a semi-solid-state battery is provided, which differs from Example 1 in that only an electrolyte is added to the battery.

[0161] Comparative Example 2

[0162] The difference from Example 1 is that no hexagonal boron nitride, solvent, or coupling agent is added to the precursor solution.

[0163] Comparative Example 3

[0164] The difference from Example 1 is that no coupling agent is added to the precursor solution.

[0165] Comparative Example 4

[0166] The difference from Example 1 is that no diluent is added to the precursor solution.

[0167] Comparative Example 5

[0168] The difference from Example 1 is that no elastomer network monomer is added to the precursor solution.

[0169] The performance of the semi-solid-state batteries prepared using the methods described in Examples 1-9 and Comparative Examples 1-5 was tested. The conductivity was measured at 25°C using a conductivity meter before polymerization. The self-extinguishing time was measured by placing a small amount of electrolyte on the negative electrode shell of the coin cell, igniting it with an igniter for 5 seconds, and then timing the self-extinguishing time. Capacity retention was used to evaluate the stability of the system during long-term cycling. The formula for measurement was: Capacity retention = Discharge capacity in the nth cycle / Discharge capacity in the first cycle (based on the LFP (LiFePO4, lithium iron phosphate) graphite system). Temperature: 25°C (room temperature cycling); Charge / discharge rate: 0.5P charge / discharge; Voltage range: 2.5V-3.65V for the LFP system. The needle penetration test uses a 5mm diameter high-temperature resistant steel needle (with a cone angle of 45°-60° at the tip, and a smooth surface free of rust, oxide layer, and oil) to penetrate the battery at a speed of 0.1mm / s, perpendicular to the large surface of the individual cell. The penetration point should be close to the geometric center of the punctured surface. The steel needle remains in the battery for 10 minutes. After monitoring voltage and temperature, observe for 1 hour and record any signs of expansion, leakage, smoke, fire, or explosion. The test results are shown in Table 1.

[0170] Table 1

[0171]

[0172] The experimental data above show that Comparative Example 1 performed poorly in terms of self-extinguishing time and thermal stability, exhibiting complete combustion and a self-extinguishing time exceeding 30 seconds, indicating a high risk of thermal runaway. The Examples demonstrated excellent safety in terms of thermal stability; all Examples exhibited self-extinguishing times of no combustion or minimal smoke, indicating a significant advantage in reducing thermal runaway. Therefore, compared to Comparative Example 1, which only used liquid electrolyte, this application significantly improves battery thermal safety by injecting the precursor solution into the battery and solidifying it to form a gel electrolyte. Examples 1 to 9 generally had shorter self-extinguishing times or did not exhibit ignition, while Comparative Examples 2 and 3 showed problems such as ignition and smoke, further confirming the important role of hexagonal boron nitride and coupling agents in improving battery thermal management capabilities. Therefore, compared to Comparative Example 2 (without hexagonal boron nitride / coupling agent) and Comparative Example 3 (without coupling agent), this application uses hexagonal boron nitride treated with a coupling agent in the gel system, which is beneficial for forming an effective heat transfer pathway and reducing heat accumulation, thereby further shortening the self-extinguishing time. In the experiment, the self-extinguishing time of the embodiments was much shorter than that of Comparative Examples 4 and 5, indicating that a reasonable ratio can effectively improve thermal stability and mechanical strength. Therefore, compared with Comparative Example 4 (without diluent) and Comparative Example 5 (without elastomer network monomers), this application forms a structurally stable gel network by reasonably setting the ratio of elastomer network monomers to diluent, thereby further improving thermal stability while maintaining ion conduction. The results of the needle penetration test showed that the batteries of Examples 1 to 11 did not catch fire during the needle penetration test, and most batteries only emitted a little smoke or no smoke, demonstrating good mechanical safety. In contrast, the comparative sample, such as Comparative Example 2, caught fire after being needled, and Comparative Example 3 emitted dense smoke and occasional sparks, showing poor performance in the needle penetration test, indicating poor thermal safety and puncture resistance. In terms of capacity retention, Examples 7 and 9 showed extremely high stability, indicating that the solid-state battery of this application can maintain good charge and discharge performance during long-term use. Compared to comparative samples, such as Comparative Example 5 with a capacity retention rate of 88.0% and Comparative Example 3 with a capacity retention rate of 82.5%, the solid-state battery of this application exhibits superior performance in capacity retention, further demonstrating that the battery's long-term stability is not affected while its thermal safety is improved. The maximum temperature of the nail penetration test is crucial for evaluating the battery's thermal response to external pressure or damage. The maximum nail penetration temperatures of Examples 1 to 9 are all in a low range, indicating that they can effectively absorb external pressure and are not prone to overheating. In contrast, the comparative samples, such as Comparative Example 2 and Comparative Example 5, have higher maximum nail penetration temperatures, further demonstrating that the solid-state battery of this application has a lower thermal response and can better prevent thermal runaway caused by mechanical impact. In summary, this application achieves the technical effect of significantly reducing the risk of combustion and thermal runaway while maintaining conductivity.

[0173] Those skilled in the art will understand that the above embodiments are specific examples of implementing this application, and in practical applications, various changes in form and detail can be made without departing from the spirit and scope of this application. Any person skilled in the art can make various alterations and modifications without departing from the spirit and scope of this application; therefore, the scope of protection of this application should be determined by the scope defined in the claims.

Claims

1. A method for preparing a semi-solid-state battery, characterized in that, include: Hexagonal boron nitride was added to a solvent to obtain the first mixture; Add a coupling agent to the first mixture to obtain a second mixture; The second mixture was subjected to ultrasonic dispersion treatment to obtain a dispersion. The elastomer network monomer, diluent, thermal initiator and electrolyte are mixed to obtain a third mixture; The dispersion was added to the third mixture to obtain the precursor solution; The precursor solution is injected into the battery, and the battery is then solidified to obtain the semi-solid battery.

2. The method according to claim 1, characterized in that, After adding hexagonal boron nitride to the solvent, the method further includes: The nanofiller is added to the solvent. The nanofiller includes Al2O3 and / or SiO2. The particle size of Al2O3 is 1-100 nm and the particle size of SiO2 is 1-100 nm. The mass of the nanofiller accounts for 0-5% of the mass of the precursor solution.

3. The method according to claim 1, characterized in that, The battery is subjected to a curing process, including: The battery is placed in an ambient heating device at a preset temperature for a preset time to allow the precursor solution to form a gel electrolyte. The preset ambient temperature is 60-70°C and the preset time is 2-4 hours.

4. The method according to claim 1, characterized in that, The hexagonal boron nitride has a sheet diameter of 0.5-5 μm and a thickness of 30-100 nm.

5. The method according to claim 1, characterized in that, The coupling agent is a silane coupling agent, including KH-550.

6. The method according to claim 1, characterized in that, The amount of coupling agent added is 1%-3% of the mass of the hexagonal boron nitride.

7. The method according to claim 1, characterized in that, The elastomeric network monomer comprises at least one of polyurethane acrylate or acrylic acid-terminated polysiloxane, and the mass of the elastomeric network monomer accounts for 4-10% of the mass of the precursor solution.

8. The method according to claim 1, characterized in that, The diluent includes polyethylene glycol diacrylate, wherein the number average molecular weight of the polyethylene glycol diacrylate is 400-700.

9. The method according to claim 1, characterized in that, The mass of the diluent is 3-5% of the mass of the precursor solution.

10. The method according to claim 1, characterized in that, The thermal initiator includes azobisisobutyronitrile.

11. The method according to claim 1, characterized in that, The hexagonal boron nitride accounts for 5-15% of the mass of the precursor solution.

12. The method according to claim 1, characterized in that, The electrolyte comprises a lithium salt and an organic solvent. The lithium salt comprises lithium hexafluorophosphate, and the organic solvent comprises ethylene carbonate (EC), diethyl carbonate (DEC), and dimethyl carbonate (DMC). The volume ratio of ethylene carbonate, diethyl carbonate, and dimethyl carbonate is 1:1:

1.

13. A semi-solid-state battery, characterized in that, The semi-solid battery is prepared by the method for preparing a semi-solid battery as described in any one of claims 1 to 12.

14. A battery device, characterized in that, Including the semi-solid-state battery as described in claim 13, the battery device includes one or more of the following: battery module, battery pack, and energy storage battery.

15. An electrical appliance, characterized in that, The electrical device includes the battery device as described in claim 14, the battery device being used to provide electrical energy.

16. An energy storage device, characterized in that, The energy storage device includes the battery device as described in claim 14, the battery device being used to store electrical energy.

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