In-situ polymerized solid-state electrolyte, method for preparing solid-state electrolyte by means of in-situ polymerization, solid-state battery, method for preparing solid-state battery, and electric device

Abstract

The present application provides an in-situ polymerized solid-state electrolyte, a method for preparing a solid-state electrolyte by means of in-situ polymerization, a solid-state battery, a method for preparing a solid-state battery, and an electric device. The in-situ polymerized solid-state electrolyte comprises a room-temperature initiator, a high-temperature initiator, a cyclic monomer polymer, and an electrolyte salt. The room-temperature initiator can exert a function in a standing period after a battery is filled with an electrolyte, to achieve electrode sheet wetting by the electrolyte and implement room temperature prepolymerization of a precursor solution, thereby improving the uniformity of the precursor solution contained in each part in the battery, and avoiding solid-liquid demixing in the precursor solution. In addition, the high-temperature initiator can improve the degree of curing of the whole electrolyte and improve the ion transport efficiency and safety of the solid-state electrolyte. The joint action of the room-temperature initiator and the high-temperature initiator comprehensively improves the uniformity of the in-situ polymerized solid-state electrolyte, and improves the quality stability of the solid-state.

Description

In-situ polymerized solid-state electrolyte, method for preparing solid-state electrolyte by in-situ polymerization, solid-state battery, method for preparing solid-state battery, and electric device

[0001] Cross-reference to related applications

[0002] This application claims priority to Chinese Patent Application No. 202410645789.X, filed on May 23, 2024, entitled “In-situ polymerized solid-state electrolyte, method for preparing solid-state electrolyte by in-situ polymerization, solid-state battery, method for preparing solid-state battery, and electric device,” which is incorporated by reference in its entirety. TECHNICAL FIELD

[0003] The present application relates to the technical field of secondary batteries, and in particular to an in-situ polymerized solid-state electrolyte, a method for preparing a solid-state electrolyte by in-situ polymerization, a solid-state battery, a method for preparing a solid-state battery, and an electric device. BACKGROUND

[0004] With the continuous development of social economy, portable devices, electric vehicles, and long-endurance energy storage devices require rechargeable batteries with long cycle life and high energy density. Lithium-ion batteries have profoundly changed daily life, however, the energy density of lithium-ion batteries is approaching the upper limit of 350 Wh·kg -1 . Compared with lithium-ion batteries, the practical energy density of lithium metal batteries can exceed 400 Wh·kg -1 , thanks to the high specific capacity and low electrode potential of the lithium metal negative electrode. However, the leakage of traditional electrolytes and the safety problems of flammability and explosion limit the application of lithium metal batteries.

[0005] Solid-state electrolytes such as polymer electrolytes can improve such problems and promote the practical application of lithium metal batteries. Traditional polymer preparation methods such as solution casting have complex preparation processes, and often have safety and environmental problems caused by solvent evaporation. In addition, the polymer electrolytes prepared by traditional methods are generally thick, which reduces the energy density of the battery, increases the transmission distance of lithium ions, and at the same time makes it difficult to fill the voids of the electrode to achieve good contact between the electrolyte and the electrode.

[0006] In-situ polymerization is a simple and compatible polymer electrolyte preparation method for existing commercial battery production, which can obtain thin and uniform polymer electrolytes, and has excellent compatibility with the electrode interface, which helps to reduce the interface impedance and improve the lithium ion transmission flux at the interface. However, the in-situ polymerized solid-state electrolyte often has the problem of uneven polymerization, which makes the yield of the solid-state battery too low to meet the requirements of industrialization and popularization, therefore, the polymerization uniformity of the in-situ polymerized solid-state electrolyte needs to be further improved to improve the forming quality stability of the solid-state battery.

[0007] The methods described in this section are not necessarily the methods that have been previously conceived or adopted. Unless otherwise indicated, nothing in this section should be construed as an admission that any method described in this section is considered to be prior art merely by virtue of its inclusion in this section. Similarly, unless otherwise indicated, nothing in this section should be considered to be prior art merely by virtue of its inclusion in this section.

[0008] SUMMARY

[0009] The present application is made in view of the above-mentioned needs, and aims to provide an in-situ polymerization solid-state electrolyte, a method for preparing a solid-state electrolyte by in-situ polymerization, a solid-state battery, a method for preparing a solid-state battery, and an electric device.

[0010] The first aspect of the present application provides an in-situ polymerization solid-state electrolyte, comprising a room-temperature initiator, a high-temperature initiator, and a cyclic monomer polymer.

[0011] The second aspect of the present application provides a method for preparing a solid-state electrolyte by in-situ polymerization, comprising mixing raw materials including a room-temperature initiator, a high-temperature initiator, and a cyclic monomer to form a precursor solution; and after standing the precursor solution at room temperature, heat-polymerizing at a high temperature to obtain the solid-state electrolyte.

[0012] The third aspect of the present application provides a solid-state battery, comprising the solid-state electrolyte of the first aspect or the solid-state electrolyte prepared by the method of the second aspect.

[0013] The fourth aspect of the present application provides a method for preparing a solid-state battery, comprising mixing raw materials including a room-temperature initiator, a high-temperature initiator, a cyclic monomer, and an electrolyte salt to form a precursor solution; injecting the precursor solution into a battery cell; and after standing the battery at room temperature, heat-polymerizing at a high temperature to obtain the solid-state battery.

[0014] The fifth aspect of the present application provides an electric device, comprising the solid-state battery of the third aspect of the present application or the solid-state battery prepared by the method of the fourth aspect of the present application.

[0015] The room-temperature initiator in the present application can play a role during the standing period after battery injection, and can cause the precursor solution to pre-polymerize at room temperature while meeting the electrolyte's requirements for electrode sheet infiltration, thereby improving the uniformity of the precursor solution contained in each part of the battery and avoiding the occurrence of solid-liquid stratification in the precursor solution. The high-temperature initiator can improve the solidification degree of the entire electrolyte and improve the ion transmission efficiency and safety of the solid-state electrolyte. In summary, through the combined action of the room-temperature initiator and the high-temperature initiator, the uniformity of the in-situ polymerization solid-state electrolyte can be improved, and the forming quality stability of the solid-state battery can be improved. BRIEF DESCRIPTION OF DRAWINGS

[0016] More details, features and advantages of the present disclosure are disclosed in the following description of exemplary embodiments in conjunction with the accompanying drawings, in which:

[0017] FIG. 1 is a dispersion state diagram of in-situ polymerized solid-state electrolyte according to an exemplary embodiment and the prior art. DETAILED DESCRIPTION

[0018] The embodiments of the technical solutions of the present application will be described in detail below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present application, and therefore only serve as examples, and cannot limit the protection scope of the present application.

[0019] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present application; the terms "include" and "have" and any variations thereof in the specification and claims of the present application and the above description of drawings are intended to cover non-exclusive inclusion.

[0020] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise explicitly and specifically limited.

[0021] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the present application. The appearance of the phrase in various places in the specification does not necessarily all refer to the same embodiment, nor is it necessarily mutually exclusive or alternative to other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0022] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship between the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the three cases of A alone, A and B together, and B alone. In addition, the character " / " in this paper generally represents a "or" relationship between the front and rear associated objects.

[0023] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two), and similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0024] It should be understood that, in the present specification, the orientations or positional relationships or dimensions indicated by the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like are based on the orientations or positional relationships or dimensions shown in the drawings, and these terms are used only for the convenience of description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the scope of protection of the present application.

[0025] In the description of the embodiments of the present application, unless otherwise explicitly specified and limited, the technical terms "mounting", "connection", "connecting", "fixing" and the like should be understood in a broad sense, for example, can be fixedly connected, or can be detachably connected, or can be integrated; can be mechanically connected, or can be electrically connected; can be directly connected, or can be indirectly connected through an intermediate medium, or can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0026] Hereinafter, only certain exemplary embodiments are simply described. As those skilled in the art can recognize, the described embodiments can be modified in various different ways without departing from the spirit or scope of the present application. Therefore, the drawings and the description are considered to be exemplary in nature rather than limiting.

[0027] The in-situ polymerization solid-state electrolyte in the prior art is usually synthesized by heat polymerization of a precursor solution. However, in the actual application process of the battery, a long time of standing is required before heat polymerization, so as to promote the infiltration of the precursor solution in the electrode sheet and reduce the interface resistance of the solid-state battery. During the standing process, the components in the precursor solution will gradually become unevenly distributed, thereby causing the uneven solidification degree of each part after polymerization, and even causing the solid-liquid layering phenomenon, which will adversely affect the safety, batch stability and electrochemical performance of the battery.

[0028] Based on this, the first aspect of the present application provides an in-situ polymerization solid-state electrolyte, comprising: a room temperature initiator, a high temperature initiator and a cyclic monomer polymer.

[0029] Herein, the room temperature initiator refers to an initiator that can generate a Lewis acid to initiate the in-situ polymerization of a cyclic monomer to generate a polymer at room temperature, for example, 0-29℃. The Lewis acid is also called an electrophile, which refers to a substance (including ions, atomic groups or molecules) that can accept an electron pair.

[0030] In the present disclosure, the high-temperature initiator refers to an initiator that can generate a Lewis acid to initiate in-situ polymerization of a cyclic monomer to generate a polymer at a high-temperature environment, for example, 30-100°C.

[0031] In the present disclosure, the cyclic monomer polymer refers to a product generated by initiating polymerization of a cyclic monomer by an initiator, and the degree of polymerization thereof is not limited.

[0032] The room-temperature initiator can play a role during the standing period after the battery is injected with electrolyte, and at the same time of meeting the electrolyte infiltration of the electrode sheet, the room-temperature pre-polymerization of the precursor solution is caused, the uniformity of the precursor solution contained in each part of the battery is improved, and the solid-liquid stratification phenomenon in the precursor solution is avoided. The high-temperature initiator can improve the solidification degree of the entire electrolyte, improve the ion transmission efficiency and safety of the solid-state electrolyte. In summary, through the joint action of the room-temperature initiator and the high-temperature initiator, the uniformity of the in-situ polymerization solid-state electrolyte can be improved, and the forming quality stability of the solid-state battery can be improved.

[0033] In some embodiments, the room-temperature initiator includes one or more of lithium hexafluorophosphate, aluminum trifluoromethanesulfonate (Al(OTF)3), scandium triflate (Sc(OTf)3), tin difluoride (SnF2), copper trifluoromethanesulfonate (Cu(OTf)2).

[0034] In some embodiments, the room-temperature initiator includes lithium hexafluorophosphate.

[0035] Lithium hexafluorophosphate can not only act as a room-temperature initiator, but also is a commonly used electrolyte salt, which will not bring negative effects to other performances of the battery due to its addition, and is conducive to the improvement of the comprehensive performance of the battery.

[0036] In some embodiments, the high-temperature initiator includes one or more of stannous octoate, lithium difluoro(oxalato)borate (LIDFOB), lithium borohydride (LiBH4), lithium aluminum hydride (LiAlH4, LAH), lithium tri-tert-butoxyaluminum hydride (LiAlH[OC(CH3)3]3, LTBA).

[0037] In some embodiments, the cyclic monomer includes one or more of a cyclic mono-olefin, a cyclic poly-olefin, a cycloalkane, a cyclic ether, a cyclic acetal, a cyclic ester, a cyclic amide, a cyclic siloxane, a cyclic ketone, and a cyclic mercaptan; optionally, the cyclic monomer includes a cyclic ether, which is optionally one or more of 1,3,5-trioxane (TXE), 1,3-dioxane, 1,4-dioxane, and 1,3-dioxolane (DOL).

[0038] In some embodiments, the solid-state electrolyte further comprises an electrolyte salt, the electrolyte salt comprising one or more of lithium bis(trifluoromethane)sulfonimide (LITFSI), lithium bis(fluorosulfonyl)imide (LIFSI), lithium bis(oxalato)borate (LIBOB), lithium tetrafluoroborate (LIBF4).

[0039] The electrolyte salt can adjust the solvation structure of lithium ions, further improving the cycle performance of the solid-state battery.

[0040] In some embodiments, the mass ratio of the room temperature initiator to the high temperature initiator is 1:1-1:10.

[0041] In some embodiments, the mass ratio of the room temperature initiator to the high temperature initiator can be selected as 1:1, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, 1:10, or a numerical range between any two of them.

[0042] The solid-state electrolyte with the mass ratio of the room temperature initiator to the high temperature initiator within the above range can balance good curing degree and uniformity, and comprehensively improve the stability of the battery forming quality.

[0043] In some embodiments, the mass ratio of the high temperature initiator to the cyclic monomer polymer is 1:100-10:100.

[0044] In some embodiments, the mass ratio of the high temperature initiator to the cyclic monomer polymer can be selected as 1:100, 2:100, 3:100, 4:100, 5:100, 6:100, 7:100, 8:100, 9:100, 10:100, or a numerical range between any two of them.

[0045] In some embodiments, the mass ratio of the electrolyte salt to the cyclic monomer polymer is 5:100-10:100.

[0046] In some embodiments, the mass ratio of the electrolyte salt to the cyclic monomer polymer can be selected as 5:100, 6:100, 7:100, 8:100, 9:100, 10:100, or a numerical range between any two of them.

[0047] In some embodiments, the solid-state electrolyte further comprises an additive.

[0048] In some embodiments, the additive comprises one or more of lithium nitrate, imidazole ionic liquid, pyrrole ionic liquid, fluorinated solvent, optionally, the fluorinated solvent comprises one or more of fluorinated ethylene carbonate, methyl trifluoroethyl carbonate (FEMC), difluoroethylene carbonate (DFEC), tris(2,2,2-trifluoroethyl) phosphate (TFEP), bis(2,2,2-trifluoroethyl) carbonate (TFEC), 2,2,2-trifluoroethyl ether (BTFE), ethyl trifluoroacetate (ETFA), 1,1,2,2-tetrafluoroethyl-2,2,2-trifluoroethyl ether, 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether.

[0049] The above-mentioned additive can improve the stability of the solid electrolyte interface film on the negative electrode surface, protect the negative electrode, especially the lithium metal negative electrode, and further improve the cycle life of the battery.

[0050] In some embodiments, the mass ratio of the additive to the cyclic monomer polymer is 1:100-5:100.

[0051] In some embodiments, the mass ratio of the additive to the cyclic monomer polymer can be 1:100, 2:100, 3:100, 4:100, 5:100, or a numerical range between any two of them.

[0052] The second aspect of the present application provides a method for preparing a solid-state electrolyte by in-situ polymerization, comprising: mixing raw materials including a room temperature initiator, a high temperature initiator, and a cyclic monomer to form a precursor solution; after the precursor solution is statically placed at room temperature, heat polymerization at high temperature to obtain the solid-state electrolyte.

[0053] The room temperature initiator can play a role during the static placement, pre-polymerize the precursor solution at room temperature while meeting the electrolyte impregnation of the electrode sheet, improve the uniformity of the precursor solution contained in each part of the battery, and avoid the solid-liquid stratification phenomenon in the precursor solution. The high temperature initiator can improve the solidification degree of the entire electrolyte, improve the ion transmission efficiency of the solid-state electrolyte, and improve the safety. In summary, through the joint action of the room temperature initiator and the high temperature initiator, the uniformity of the in-situ polymerized solid-state electrolyte can be improved, and the forming quality stability of the solid-state battery can be improved.

[0054] In some embodiments, the static placement time of the precursor solution is 36-50 hours.

[0055] In some embodiments, the static placement time of the precursor solution can be 36 hours, 40 hours, 45 hours, 50 hours, or a numerical range between any two of them.

[0056] In some embodiments, the polymerization temperature of the thermal polymerization at high temperature is 30-100°C; and / or the polymerization time of the thermal polymerization at high temperature is 0.5-1.5 hours.

[0057] In some embodiments, the polymerization temperature of the thermal polymerization at high temperature can be selected from 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, or any numerical range between any two of them.

[0058] In some embodiments, the polymerization time of the thermal polymerization at high temperature can be selected from 0.5 hours, 1 hour, 1.5 hours, or any numerical range between any two of them.

[0059] In some embodiments, the raw materials further include electrolyte salt and additives, and the mixing includes raw materials including room temperature initiator, high temperature initiator, and cyclic monomer, to form a precursor solution, which includes mixing the cyclic monomer, electrolyte salt, and additives to obtain a first mixture; mixing the first mixture with the high temperature initiator to obtain a second mixture; and mixing the second mixture with the room temperature initiator to obtain the precursor solution.

[0060] The above method can minimize the influence of the addition of the room temperature initiator on the viscosity of the precursor solution, thereby improving the injectability of the precursor solution.

[0061] In some embodiments, the mass ratio of the room temperature initiator to the high temperature initiator is 1:1-1:10.

[0062] In some embodiments, the mass ratio of the high temperature initiator to the cyclic monomer is 1:100-10:100.

[0063] In some embodiments, the mass ratio of the electrolyte salt to the cyclic monomer is 5:100-10:100.

[0064] The third aspect of the present application provides a solid-state battery including the solid-state electrolyte of any of the embodiments or the solid-state electrolyte prepared by the method of any of the embodiments.

[0065] In some embodiments, the solid-state battery includes a lithium metal anode.

[0066] The fourth aspect of the present application provides a method for preparing a solid-state battery, which includes mixing raw materials including room temperature initiator, high temperature initiator, cyclic monomer, and electrolyte salt to form a precursor solution; injecting the precursor solution into an electric cell; and after the cell is left at room temperature, performing thermal polymerization at high temperature to obtain the solid-state battery.

[0067] The solid-state electrolyte obtained by the method is thin and uniform, and has low interfacial impedance with the electrolyte interface, so that the solid-state battery has high stability of the formed product.

[0068] A fifth aspect of the present application provides a power-using device comprising the solid-state battery of any of the embodiments or the solid-state battery prepared by the preparation method of any of the embodiments.

[0069] Embodiments

[0070] Hereinafter, the embodiments of the present application will be described. The embodiments described below are exemplary and are for the purpose of explanation of the present application only and are not to be understood as a limitation of the present application. In the embodiments, the specific techniques or conditions not mentioned are performed according to the techniques or conditions described in the literature in the art or according to the product instructions. The reagents or instruments not mentioned by the manufacturer are all conventional products that can be obtained by purchase.

[0071] I. Preparation method

[0072] Example 1

[0073] 1) Preparation of precursor solution

[0074] At room temperature, 100 parts by mass, 5 parts by mass, 4 parts by mass, 1 part by mass of cyclic monomer 1,3,5-trioxane (TXE), electrolyte salt lithium bis(oxalato)borate (LiBOB), additive FEC and N-propyl-N-methylpyrrolidinium nitrate were weighed into a glass bottle, respectively, and mixed uniformly to obtain a first mixture; then 5 parts by mass of high-temperature initiator LIDFOB was added, and the mixture was mixed uniformly to obtain a second mixture. Then 1 part by mass of room-temperature initiator lithium hexafluorophosphate LIPF6 was added to the second mixture to form a precursor solution.

[0075] 2) Assembly of battery

[0076] NCM811 was used as the positive electrode active material of the battery, and lithium was used as the negative electrode of the battery. After the positive electrode sheet, the separator and the negative electrode sheet were stacked and assembled, the above-mentioned precursor solution was injected to complete the assembly of the battery.

[0077] After the above-mentioned battery was placed at room temperature for 48 hours, the room-temperature initiator was allowed to function, and then it was placed in an 80-degree Celsius oven for thermal polymerization for 1 hour to allow the high-temperature initiator to function, thereby forming a solid-state electrolyte in situ.

[0078] Example 2

[0079] The battery assembly method of Example 2 is consistent with that of Example 1, except that the preparation method of the precursor solution is different: the room-temperature initiator in the precursor solution in Example 2 is aluminum trifluoromethanesulfonate (Al(OTF)3).

[0080] Example 3

[0081] Example 3 is consistent with the battery assembly method of Example 1, except that the preparation method of the precursor solution is different: the high-temperature initiator in the precursor solution in Example 3 is stannous octoate.

[0082] Example 4

[0083] Example 4 is consistent with the battery assembly method of Example 1, except that the preparation method of the precursor solution is different: the mass ratio of the room-temperature initiator to the high-temperature initiator in the precursor solution in Example 4 is 1:1.

[0084] Example 5

[0085] Example 5 is consistent with the battery assembly method of Example 1, except that the preparation method of the precursor solution is different: the mass ratio of the room-temperature initiator to the high-temperature initiator in the precursor solution in Example 5 is 1:10.

[0086] Comparative Example 1

[0087] Comparative Example 1 is consistent with the battery assembly method of Example 1, except that the preparation method of the precursor solution is different: the preparation method of the precursor solution in Comparative Example 1 is as follows:

[0088] At room temperature, 100 parts by mass, 5 parts by mass, 4 parts by mass, and 1 part by mass of the cyclic monomer 1,3,5-trioxane (TXE), the electrolyte salt lithium bis(oxalato)borate (LiBOB), the additive FEC, and N-propyl-N-methylpyrrolidinium nitrate were weighed into a glass bottle, respectively, and mixed uniformly to obtain a first mixture. Then, 5 parts by mass of the high-temperature initiator LIDFOB was added, and the mixture was mixed uniformly to obtain a second mixture.

[0089] Comparative Example 2

[0090] Comparative Example 2 is consistent with the battery assembly method of Example 1, except that the preparation method of the precursor solution is different: the preparation method of the precursor solution in Comparative Example 2 is as follows:

[0091] At room temperature, 100 parts by mass, 5 parts by mass, 4 parts by mass, and 1 part by mass of the cyclic monomer 1,3,5-trioxane (TXE), the electrolyte salt lithium bis(oxalato)borate (LiBOB), the additive FEC, and N-propyl-N-methylpyrrolidinium nitrate were weighed into a glass bottle, respectively, and mixed uniformly to obtain a first mixture. Then, 1 part by mass of the room-temperature initiator lithium hexafluorophosphate LIPF6 was added to the first mixture to form a precursor solution.

[0092] II. Performance Test

[0093] 1) Uniformity Test

[0094] The precursor solution is placed in a glass bottle, and the uniformity of the solution in the glass bottle is observed; after standing for 48 hours, the uniformity of the solution in the glass bottle is observed; after continuing to be placed in an 80-degree Celsius oven for one hour, the solid-state electrolyte is observed.

[0095] If the solid-state electrolyte is uniform and completely solidified, it is determined that the precursor solution is solidified uniformly, and is Y; if the solid-state electrolyte is not completely solidified or there is a delamination phenomenon, it is determined that the precursor solution is not solidified uniformly, and is N.

[0096] 2) Good product rate test of solid-state battery

[0097] The discharge capacity / cycle capacity retention rate of the solid-state battery is tested by using a new Wei electrochemical workstation, and a discharge capacity higher than 0.23 Ah indicates a good product, otherwise a substandard product. Using the same batch of precursor solution, 50 secondary batteries are prepared, and the good product rate is measured. The good product rate is the number of good products / the total number of samples.

[0098] III. Analysis of test results of each embodiment and comparative example

[0099] The batteries of each embodiment and comparative example are prepared according to the above method, and each performance parameter is measured, and the results are shown in the following table.

[0100] Table 1

[0101] The solid-state electrolyte after in-situ polymerization in Example 1, Comparative Example 1 and Comparative Example 2 is shown in (a), (b) and (c) of FIG. 1, respectively. As can be seen from the figure, the solid-state electrolyte after in-situ polymerization in Example 1 presents a uniform emulsion; while the solid-state electrolyte after in-situ polymerization in Comparative Example 1 shows obvious solid-liquid separation, and the solid-state electrolyte after in-situ polymerization in Comparative Example 2 shows flocculation due to insufficient polymerization degree.

[0102] As can be seen from the comparison of the embodiments and comparative examples, by simultaneously including a room temperature initiator and a high temperature initiator in the solid-state electrolyte, the uniformity of the in-situ polymerization of the electrolyte can be improved, and the good product rate of the solid-state battery can be improved.

[0103] It should be noted that the present application is not limited to the above embodiments. The above embodiments are only examples, and embodiments having the same technical idea and playing the same role and effect within the scope of the technical solutions of the present application are all included in the technical scope of the present application. In addition, within the scope of the main idea of the present application, various modifications of the embodiments that can be thought of by those skilled in the art, and other ways constructed by combining part of the constituent elements in the embodiments are also included in the scope of the present application.

Claims

1. An in-situ polymerized solid-state electrolyte, characterized by, Comprising: a room temperature initiator, a high temperature initiator, and a cyclic monomer polymer.

2. The solid-state electrolyte of claim 1, wherein, the room temperature initiator comprises one or more of lithium hexafluorophosphate, aluminum trifluoromethanesulfonate (Al(OTF)3), scandium triflate (Sc(OTf)3), tin difluoride (SnF2), copper triflate (Cu(OTf)2).

3. The solid-state electrolyte of claim 1, wherein, the high temperature initiator comprises one or more of stannous octoate, lithium difluoro(oxalato)borate (LIDFOB), lithium borohydride (LiBH4), lithium aluminum hydride (LiAlH4, LAH), lithium tri-tert-butoxyaluminum hydride (LiAlH[OC(CH3)3]3, LTBA).

4. The solid-state electrolyte of claim 1, wherein, the cyclic monomer comprises one or more of a cyclic mono-olefin, a cyclic poly-olefin, a cyclic alkane, a cyclic ether, a cyclic acetal, a cyclic ester, a cyclic amide, a cyclic siloxane, a cyclic ketone, a cyclic thiol; optionally, the cyclic monomer comprises a cyclic ether, optionally one or more of 1,3,5-trioxane (TXE), 1,3-dioxane, 1,4-dioxane, 1,3-dioxolane (DOL).

5. The solid-state electrolyte of claim 1, wherein, the solid-state electrolyte further comprises an electrolyte salt, the electrolyte salt comprises one or more of lithium bis(trifluoromethane)sulfonimide (LITFSI), lithium bis(fluorosulfonyl)imide (LIFSI), lithium bis(oxalato)borate (LIBOB), lithium tetrafluoroborate (LIBF4).

6. The solid-state electrolyte of claim 1, wherein, the solid-state electrolyte satisfies at least one of the following conditions: (1) the mass ratio of the room temperature initiator to the high temperature initiator is 1:1-1:10; (2) the mass ratio of the high temperature initiator to the cyclic monomer polymer is 1:100-10:100; (3) the mass ratio of the electrolyte salt to the cyclic monomer polymer is 5:100-10:

100.

7. The solid-state electrolyte of claim 1, wherein, the solid-state electrolyte further comprises an additive, the additive comprises one or more of lithium nitrate, an imidazolium-based ionic liquid, a pyrrolidinium-based ionic liquid, a fluorinated solvent, optionally, the fluorinated solvent comprises one or more of fluoroethylene carbonate, methyltrifluoroethyl carbonate (FEMC), bisfluoroethylene carbonate (DFEC), tris(2,2,2-trifluoroethyl) phosphate (TFEP), bis(2,2,2-trifluoroethyl) carbonate (TFEC), 2,2,2-trifluoroethyl ether (BTFE), ethyl trifluoroacetate (ETFA), 1,1,2,2-tetrafluoroethyl-2,2,2-trifluoroethyl ether, 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether.

8. The solid-state electrolyte of claim 7, wherein, the mass ratio of the additive to the cyclic monomer polymer is 1:100-5:

100.

9. A method of in-situ polymerization to produce a solid-state electrolyte, characterized by, Comprising: mixing raw materials including room temperature initiator, high temperature initiator, cyclic monomer, to form a precursor solution; after the precursor solution is left at room temperature, heat polymerization at high temperature to obtain the solid-state electrolyte.

10. The method of claim 9, wherein, the standing time of the precursor solution left at room temperature is 36-50 hours.

11. The method of claim 9, wherein, the polymerization temperature of the heat polymerization at high temperature is 30-100 degrees Celsius; and / or the polymerization time of the heat polymerization at high temperature is 0.5-1.5 hours.

12. The method of claim 9, wherein, the raw materials further include electrolyte salt and additives, the mixing raw materials including room temperature initiator, high temperature initiator, cyclic monomer, to form a precursor solution includes: mixing cyclic monomer, electrolyte salt and additives to obtain a first mixture; mixing the first mixture with high temperature initiator to obtain a second mixture; mixing the second mixture with room temperature initiator to obtain a precursor solution.

13. A solid state battery, characterized by the solid-state electrolyte of any one of claims 1-8 or prepared by the method of any one of claims 9-12.

14. The solid-state battery of claim 13, wherein, the solid-state battery includes lithium metal anode.

15. A method of making a solid state battery, characterized by, comprising: mixing raw materials including room temperature initiator, high temperature initiator, cyclic monomer, electrolyte salt, to form a precursor solution; injecting the precursor solution into the battery cell; after the battery is left at room temperature, heat polymerization at high temperature to obtain the solid-state battery.

16. An electrical device, comprising: the solid-state battery of claim 13 or 14 or prepared by the method of claim 15.

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