Polymer solid electrolyte and method for producing the same

Abstract

The object of the present invention is to provide a polymer solid electrolyte with excellent safety and ionic conductivity, and a method for producing the same. [Solution] The present invention relates to a polymer solid electrolyte, a method for producing the same, and an all-solid-state battery containing the same. More specifically, by mixing liquid-phase polyhedral oligomeric silsesquioxane (POSS) with a single ion conductor to improve the fluidity of the polymer chain, the safety and ionic conductivity of the polymer solid electrolyte can be improved simultaneously.

Description

[Technical Field] 【0001】 This application claims priority under Korean Patent Application No. 10-2022-0138015 dated October 25, 2022, and incorporates all the contents disclosed in the said Korean Patent Application as part of this Specification. 【0002】 The present invention relates to polymer solid electrolytes and methods for producing the same. [Background technology] 【0003】 Lithium-ion batteries, which use liquid electrolytes, have a structure in which the negative and positive electrodes are separated by a separator membrane. If the separator membrane is damaged due to deformation or external impact, a short circuit can occur, which can lead to dangers such as overheating and explosion. Therefore, the development of solid electrolytes that can ensure safety in the field of lithium-ion batteries is a very important issue. 【0004】 Lithium-ion batteries using solid electrolytes offer several advantages, including improved battery safety, reduced electrolyte leakage, enhanced reliability, and easier manufacturing of thin batteries. Furthermore, the use of lithium metal as the negative electrode allows for increased energy density, making them promising for applications such as small secondary batteries and high-capacity secondary batteries for electric vehicles, and attracting attention as a next-generation battery. 【0005】 Among solid electrolytes, polymer solid electrolytes may use ion-conducting polymer materials as raw materials, and hybrid materials in which polymer materials and inorganic materials are mixed have also been proposed. As the inorganic material, inorganic materials such as oxides or sulfides may be used. 【0006】 Conventional polymer solid electrolytes were manufactured through a process of forming a coating film followed by high-temperature drying. However, conventional polymer solid electrolyte manufacturing techniques had limitations in that it was difficult to produce polymer solid electrolytes with improved ionic conductivity due to the high crystallinity of crystalline polymers or semi-crystalline polymers. 【0007】 Furthermore, polymer solid electrolytes are generally dual-ion conductors in which lithium cations and their corresponding anions are all fluid. Here, lithium ions have lower fluidity than anions because they bind to Lewis basic sites in the polymer matrix. Therefore, the lithium ion transport number of dual-ion conductors is generally 0.5 or less. In conventional polymer solid electrolytes, lithium ions and their corresponding anions move in opposite directions during discharge, and anions tend to accumulate on the negative electrode side. This causes a concentration gradient and cell polarization, and if this phenomenon continues, battery performance may deteriorate. 【0008】 On the other hand, single-ion conductors, which are single-ion conducting polymer solid electrolytes, have attracted considerable attention because anions are fixed to the polymer chain, they can exhibit a lithium-ion transport number close to 1, and they do not have a harmful effect on the anion polarization. However, it is very difficult for such single-ion conducting polymer solid electrolytes to simultaneously possess high ionic conductivity and safety. 【0009】 Therefore, there is a need to develop technologies that can simultaneously ensure ionic conductivity and stability using single-ion conductive polymer solid electrolytes, which have recently attracted attention. [Prior art documents] [Patent Documents] 【0010】 [Patent Document 1] Korean Published Patent Gazette No. 2017-0046995 [Overview of the Initiative] [Problems that the invention aims to solve] 【0011】 The inventors conducted multifaceted research to solve the aforementioned problems and confirmed that by adding liquid-phase polyhedral oligomeric silsesquioxane (POSS) to a single ion conductor, the chain mobility of the polymer chain was improved, thereby simultaneously improving the safety and ionic conductivity of the polymer solid electrolyte. 【0012】 Therefore, the object of the present invention is to provide a polymer solid electrolyte with excellent safety and ionic conductivity, and a method for producing the same. 【0013】 Another object of the present invention is to provide an all-solid-state battery containing a polymer solid electrolyte with improved safety and ionic conductivity. 【0014】 Another object of the present invention is to provide a battery module including the all-solid-state battery. [Means for solving the problem] 【0015】 To achieve the above objective, the present invention provides a polymer solid electrolyte comprising a single ion conductor and a liquid-phase polyhedral oligomeric silsesquioxane (POSS). 【0016】 The present invention also provides a method for producing a solid polymer electrolyte, comprising: (S1) forming a solution for forming a solid polymer electrolyte, the solution containing a single ion conductor and a liquid-phase polyhedral oligomeric silsesquioxane (POSS); (S2) applying the solution for forming the solid polymer electrolyte onto a substrate to form a coating film; and (S3) drying the coating film. 【0017】 The present invention also provides a all-solid-state battery comprising the solid polymer electrolyte. 【0018】 The present invention also provides a battery module comprising the all-solid-state battery. 【Advantages of the Invention】 【0019】 The solid polymer electrolyte according to the present invention has a structure in which polymer chains are intertwined with the single ion conductor itself, and thus exhibits excellent safety and ionic conductivity. 【0020】 In addition, due to the cage structure contained in the liquid-phase polyhedral oligomeric silsesquioxane (POSS), the chain mobility of the polymer chains can be improved, and thus the ionic conductivity can be further improved. 【Brief Description of the Drawings】 【0021】 [Figure 1] It is a schematic diagram showing the internal structure of a solid polymer electrolyte according to an embodiment of the present invention. 【Embodiments for Carrying Out the Invention】 【0022】 Hereinafter, the present invention will be described in more detail to facilitate understanding of the present invention. 【0023】 The terms and words used in this specification and in the claims should not be interpreted in a manner limited to their ordinary or lexicographical meanings, but rather in a manner consistent with the technical idea of ​​the present invention, based on the principle that inventors may appropriately define the concepts of terms in order to best describe their invention. 【0024】 Polymer solid electrolyte This invention relates to polymer solid electrolytes. 【0025】 The polymer solid electrolyte according to the present invention comprises a single ion conductor (SIC) and a liquid-phase polyhedral oligomeric silsesquioxane (POSS). Furthermore, the polymer solid electrolyte may further contain a lithium salt to further improve its ionic conductivity. 【0026】 Figure 1 is a schematic diagram showing the internal structure of a polymer solid electrolyte according to one embodiment of the present invention. 【0027】 Referring to Figure 1, the polymer solid electrolyte (1) may have a structure in which polymer chains contained in a single ion conductor (10) are intertwined. Furthermore, the internal space formed by the polymer chains may contain liquid-phase polyhedral oligomeric silsesquioxane (POSS) (20), and a lithium salt (not shown) may also be contained in the internal space in a dissociated state. 【0028】 In the present invention, the single ion conductor may be a fluorine-based polymer electrolyte membrane. Specifically, the single-ion conductor contains a perfluorosulfonic acid (PFSA) polymer, and the hydrogen atoms of the sulfonic acid groups (-SO3H) contained in the perfluorosulfonic acid polymer are lithium cations (Li + The structure is substituted with lithium cation (Li). The single-ionic conductor is lithium cation (Li+ Because it contains ), it has excellent ionic conductivity. The perfluorosulfonic acid polymer may be Nafion (Dupont), Flemion (Asahi Glass), Aciplex (KRAsahi Kasei), or Aquivion (Merck). 【0029】 The aforementioned perfluorosulfonic acid-based polymer is suitable as a polymer electrolyte membrane due to its excellent mechanical stability, thermal stability, and high ionic conductivity. 【0030】 Furthermore, the single-ion conductor may be included in an amount of 20% to 60% by weight based on the total weight of the polymer solid electrolyte. Specifically, it may be included in an amount of 20% or more by weight, 25% or more by weight, or 30% or more by weight, or in an amount of 50% or less by weight, 55% or less by weight, or 60% or less by weight. If the content of the single-ion conductor is less than 20% by weight, it is difficult to form a film-like polymer solid electrolyte, and if it exceeds 60% by weight, the content of the polyhedral oligomeric silsesquioxane in the liquid phase decreases relatively, and the improvement effect on ionic conductivity may be minimal. 【0031】 In the present invention, the polyhedral oligomeric silsesquioxane (POSS) in the liquid phase may be represented by the following chemical formula 1: 【0032】 [ka] 【0033】 In the aforementioned chemical formula 1, R is selected from the group consisting of groups that are either identical or different and independently represented by the following chemical formulas 1-1 to 1-4: 【0034】 [ka] 【0035】 [ka] 【0036】 [ka] 【0037】 [ka] 【0038】 In the above chemical formulas 1-1 to 1-4, L1 to L5 are alkylene groups of C1 to C30. R1 to R4 are selected from the group consisting of hydrogen; hydroxyl group; amino group; thiol group; C1 to C30 alkyl group; C2 to C30 alkenyl group; C2 to C30 alkynyl group; C1 to C30 alkoxy group; and C1 to C30 carboxyl group. m and n are either identical or different, and each is an independent integer between 0 and 10. * indicates a binding position. 【0039】 Furthermore, in the above chemical formulas 1-1 to 1-4, L1 to L5 are C1 to C10 alkylene groups, R1 to R4 are hydrogen; hydroxyl groups; or C1 to C30 alkyl groups, and m and n are either the same or different from each other, and are independently integers from 0 to 10. 【0040】 Furthermore, in the above chemical formula 1, R is selected from the group consisting of polyethylene glycol group, glycidyl group, octasilane group, and methacrylic group. 【0041】 Preferably, the polyhedral oligomeric silsesquioxane (POSS) is polyethylene glycol-polyhedral oligomeric silsesquioxane (PEG-POSS), where R in chemical formula 1 is a polyethylene glycol group (PEG). 【0042】 Furthermore, the polyhedral oligomeric silsesquioxane (POSS) in the liquid phase may be present in an amount of 20% to 60% by weight based on the total weight of the polymer solid electrolyte. Specifically, the content of polyhedral oligomeric silsesquioxane in the liquid phase may be 20% or more by weight, 25% or more by weight, or 30% or more by weight, or 50% or less by weight, 55% or less by weight, or 60% or less by weight. If the content of polyhedral oligomeric silsesquioxane in the liquid phase is less than 20% by weight, the effect of improving ionic conductivity may be minimal, and if it exceeds 60% by weight, the content of the single ion conductor will relatively decrease, making it difficult to manufacture a film-like polymer solid electrolyte. Furthermore, within the aforementioned weight range, the single-ion conductor and the liquid-phase polyhedral oligomeric silquioxane may be present in a weight ratio of 1:1 to 1:2. If the weight ratio exceeds 1:1, the improvement effect on ionic conductivity may be minimal, and if it is less than 1:2, phase separation may occur. 【0043】 In the present invention, the lithium salt is contained in a dissociated state within the internal space of the polymer chain of the single-ion conductor, and the ionic conductivity of the polymer solid electrolyte can be improved. 【0044】 The lithium salts mentioned above are (CF3SO2)2NLi (Lithium bis(trifluoromethanesulfonyyl)imide, LiTFSI), (FSO2)2NLi (Lithium bis(fluorosulfonyl)imide, LiFSI), LiNO3, LiOH, LiCl, LiBr, LiI, LiClO4, LiBF4, and LiB 10 Cl 10 It may also contain one or more selected from the group consisting of LiPF6, LiCF3SO3, LiCF3CO2, LiAsF6, LiSbF6, LiAlCl4, CH3SO3Li, CF3SO3Li, LiSCN, and LiC(CF3SO2)3. 【0045】 Furthermore, the lithium salt may be included in an amount of 10% to 30% by weight based on the total weight of the polymer solid electrolyte. Specifically, the content of the lithium salt may be 10% or more by weight, 13% or more by weight, or 15% or more by weight, or 20% or less by weight, 25% or less by weight, or 30% or less by weight. If the content of the lithium salt is less than 10% by weight, the effect of improving ionic conductivity may be minimal, and if it exceeds 30% by weight, there may be no benefit from increasing the content. 【0046】 In the present invention, the polymer solid electrolyte may be in the form of a free-standing film or a coating layer. The free-standing film means a film that can maintain its film-like state on its own at room temperature and pressure without the need for a separate support. The coating layer means a layer obtained by coating a substrate. 【0047】 The freestanding film or coating layer has the properties of a support that stably contains lithium ions, and is therefore a suitable form for a polymer solid electrolyte. 【0048】 In the present invention, the polymer solid electrolyte may further contain a liquid electrolyte, and the liquid electrolyte can further improve the ionic conductivity of the polymer solid electrolyte. The liquid electrolyte may also be contained within the internal space of the three-dimensional structure. 【0049】 The liquid electrolyte may be any liquid electrolyte commonly used in the industry, and its composition is not particularly limited as long as it can be used in a lithium secondary battery. For example, the liquid electrolyte may contain a lithium salt and a non-aqueous solvent. The lithium salt may be any of the lithium salts described above. The non-aqueous solvent may also contain one or more selected from the group consisting of propylene carbonate (PC), ethylene carbonate (EC), vinylene carbonate (VC), diethyl carbonate (DEC), dimethyl carbonate (DMC), methyl ethyl carbonate (MEC), ethyl methyl carbonate (EMC), tetrahydrofuran (THF), 2-methyltetrahydrofuran (2MeTHF), dioxolane (DOX), dimethoxyethane (DME), diethoxyethane (DEE), γ-butyrolactone (GBL), acetonitrile (AN), and sulfolane. 【0050】 Furthermore, the liquid electrolyte may be included in an amount of 1 to 5% by weight based on the total weight of the polymer solid electrolyte. If the liquid electrolyte content is 1% by weight or less, the effect of improving ionic conductivity may be minimal, and if it exceeds 5% by weight, stability may decrease. 【0051】 Method for producing polymer solid electrolytes The present invention also relates to a method for producing a solid electrolyte, the method for producing the solid electrolyte comprising: (S1) forming a polymer solid electrolyte forming solution comprising a single ion conductor and a liquid-phase polyhedral oligomeric silsesquioxane (POSS); (S2) applying the polymer solid electrolyte forming solution onto a substrate to form a coating film; and (S3) drying the coating film. In step (S1), a lithium salt may be further used to obtain the polymer solid electrolyte forming solution. 【0052】 The method for producing a solid electrolyte according to the present invention will be described in more detail below, step by step. 【0053】 In the present invention, step (S1) can form a polymer solid electrolyte solution containing a single ion conductor and a liquid-phase polyhedral oligomeric silsesquioxane (POSS). A lithium salt may be further added to increase the ionic conductivity. The types and contents of the single ion conductor, the liquid-phase polyhedral oligomeric silsesquioxane (POSS), and the lithium salt are as described above. 【0054】 Since the polyhedral oligomeric silsesquioxane (POSS) exists in the liquid phase at room temperature, the liquid-phase polyhedral oligomeric silsesquioxane may be mixed with a single-ion conductor to form a polymer solid electrolyte solution. A lithium salt may also be added. 【0055】 In the present invention, in step (S2), the polymer solid electrolyte forming solution can be applied to a substrate to form a coating film. 【0056】 The substrate is not particularly limited as long as it can serve as a support to which the polymer solid electrolyte forming solution is applied. For example, the substrate may be SUS (Stainless Use Steel), polyethylene terephthalate film, polytetrafluoroethylene film, polyethylene film, polypropylene film, polybutene film, polybutadiene film, vinyl chloride copolymer film, polyurethane film, ethylene-vinyl acetate film, ethylene-propylene copolymer film, ethylene-ethyl acrylate copolymer film, ethylene-methyl acrylate copolymer film, or polyimide film. 【0057】 Furthermore, the coating method is not particularly limited as long as it is a method that can coat the polymer solid electrolyte forming solution onto the substrate in a film-like manner. For example, the coating method may be bar coating, roll coating, spin coating, slit coating, die coating, blade coating, comma coating, slot die coating, lip coating, or solution casting. 【0058】 In the present invention, in step (S3), the coated film can be dried to obtain a polymer solid electrolyte. 【0059】 all solid state battery The present invention also relates to an all-solid-state battery comprising the polymer solid electrolyte. The all-solid-state battery comprises a positive electrode layer, a negative electrode layer, and a solid electrolyte layer formed between the positive electrode layer and the negative electrode layer, wherein at least one of the positive electrode layer, the negative electrode layer, and the solid electrolyte layer may contain the polymer solid electrolyte. 【0060】 If the positive electrode layer contains a polymer solid electrolyte, the polymer solid electrolyte may be formed on one side of the positive electrode active material layer. Similarly, if the negative electrode layer contains a polymer solid electrolyte, the polymer solid electrolyte may be formed on one side of the negative electrode active material layer. When the positive electrode layer and / or the negative electrode layer contain a polymer solid electrolyte, the effect of improving the electrical conductivity of the positive and negative electrodes can be achieved. 【0061】 Furthermore, if the solid electrolyte layer contains the polymer solid electrolyte, it can itself perform the function of an electrolyte. 【0062】 In the present invention, the positive electrode included in the all-solid-state battery includes a positive electrode active material layer, and the positive electrode active material layer may be formed on one side of a positive electrode current collector. 【0063】 The positive electrode active material layer contains a positive electrode active material, a binder, and a conductive material. 【0064】 Moreover, the positive electrode active material is not particularly limited as long as it can reversibly occlude and release lithium ions. For example, lithium cobalt oxide (LiCoO2), lithium nickel oxide (LiNiO2), Li[Ni x Co y Mn z M v O2 (in the above formula, M is any one selected from the group consisting of Al, Ga, and In or two or more of these elements; 0.3 ≦ x < 1.0, 0 ≦ y, z ≦ 0.5, 0 ≦ v ≦ 0.1, x + y + z + v = 1), Li(Li a M b-a-b’ M’ b’ )O 2-c A c (in the above formula, 0 ≦ a ≦ 0.2, 0.6 ≦ b ≦ 1, 0 ≦ b’ ≦ 0.2, 0 ≦ c ≦ 0.2, M includes Mn and one or more selected from the group consisting of Ni, Co, Fe, Cr, V, Cu, Zn, and Ti; M’ is one or more selected from the group consisting of Al, Mg, and B, and A is one or more selected from the group consisting of P, F, S, and N.) and other layered compounds, or compounds substituted with one or more transition metals; chemical formula Li 1+y Mn 2-y O4 (where y is 0 to 0.33), lithium manganese oxides such as LiMnO3, LiMn2O3, LiMnO2; lithium copper oxide (Li2CuO2); vanadium oxides such as LiV3O8, LiFe3O4, V2O5, Cu2V2O7; chemical formula LiNi 1-y MyO2 (where M = Co, Mn, Al, Cu, Fe, Mg, B, or Ga, and y is 0.01 to 0.3) and Ni-site type lithium nickel oxides represented by; chemical formula LiMn 2-y M yLithium manganese composite oxides represented as O2 (where M is Co, Ni, Fe, Cr, Zn, or Ta, and y is 0.01 to 0.1) or Li2Mn3MO8 (where M is Fe, Co, Ni, Cu, or Zn); LiMn2O4 in which part of the Li in the chemical formula is substituted with alkaline earth metal ions; disulfide compounds; Fe2(MoO4)3, etc., are examples, but are not limited to these. 【0065】 Furthermore, the positive electrode active material may be included in an amount of 40 to 80% by weight based on the total weight of the positive electrode active material layer. Specifically, the content of the positive electrode active material may be 40% or more by weight, 50% or more by weight, or 70% or less by weight, or 80% or less by weight. If the content of the positive electrode active material is less than 40% by weight, the connectivity between the wet positive electrode active material layer and the dry positive electrode active material layer may become insufficient, and if it exceeds 80% by weight, the mass transfer resistance may increase. 【0066】 Furthermore, the binder contains components that assist in the bonding of the positive electrode active material to conductive materials and to the current collector, such as styrene-butadiene rubber, acrylic styrene-butadiene rubber, acrylonitrile copolymer, acrylonitrile-butadiene rubber, nitrile-butadiene rubber, acrylonitrile-styrene-butadiene copolymer, acrylic rubber, butyl rubber, fluororubber, polytetrafluoroethylene, polyethylene, polypropylene, ethylene / propylene copolymer, polybutadiene, polyethylene oxide, chlorosulfonated polyethylene, polyvinylpyrrolidone, polyvinylpyridine, polyvinyl alcohol, polyvinyl acetate, polyepichlorohydrin, polyphosphazene, and polyacrylic acid. The binder may contain one or more selected from the group consisting of lilonitrile, polystyrene, latex, acrylic resin, phenolic resin, epoxy resin, carboxymethylcellulose, hydroxypropylcellulose, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cyanoethylcellulose, cyanoethyl scrosate, polyester, polyamide, polyether, polyimide, polycarboxylate, polycarboxylic acid, polyacrylic acid, polyacrylate, lithium polyacrylate, polymethacrylic acid, polymethacrylate, polyacrylamide, polyurethane, polyvinylidene fluoride, and poly(vinylidene fluoride)-hexafluoropropene. Preferably, the binder may contain one or more selected from the group consisting of styrene-butadiene rubber, polytetrafluoroethylene, carboxymethylcellulose, polyacrylic acid, lithium polyacrylate, and polyvinylidene fluoride. 【0067】 Furthermore, the binder may be included in an amount of 1% to 30% by weight based on the total weight of the positive electrode active material layer. Specifically, the binder content may be 1% or more by weight, 3% or more by weight, 15% or less by weight, or 30% or less by weight. If the binder content is less than 1% by weight, the adhesive strength between the positive electrode active material and the positive electrode current collector may decrease. If it exceeds 30% by weight, the adhesive strength will improve, but the content of the positive electrode active material will decrease accordingly, potentially reducing the battery capacity. 【0068】 Furthermore, the conductive material is not particularly limited as long as it prevents side reactions in the internal environment of the all-solid-state battery, does not induce chemical changes in the battery, and has excellent electrical conductivity. Typically, graphite or conductive carbon may be used, for example: graphite such as natural graphite or artificial graphite; carbon black such as carbon black, acetylene black, Ketjen black, Denka black, thermal black, channel black, furnace black, lamp black, and summer black; carbon-based materials whose crystalline structure is graphene or graphite; conductive fibers such as carbon fibers and metal fibers; carbon fluoride; metal powders such as aluminum powder and nickel powder; conductive whiskers such as zinc oxide and potassium titanate; conductive oxides such as titanium oxide; and conductive polymers such as polyphenylene derivatives. These may be used individually or in combination of two or more, but are not necessarily limited to these. 【0069】 The conductive material may be included in an amount of 0.5% to 30% by weight based on the total weight of the positive electrode active material layer. Specifically, the content of the conductive material may be 0.5% or more by weight, or 1% or more by weight, or 20% or less by weight, or 30% or less by weight. If the content of the conductive material is too low, less than 0.5% by weight, it may be difficult to expect an improvement in electrical conductivity, or the electrochemical properties of the battery may deteriorate. If it is too high, exceeding 30% by weight, the amount of positive electrode active material will be relatively small, and the capacity and energy density may decrease. The method of incorporating the conductive material into the positive electrode is not particularly limited, and conventional methods known in the art, such as coating the positive electrode active material, may be used. 【0070】 Furthermore, the positive electrode current collector supports the positive electrode active material layer and plays a role in transferring electrons between the external conductor and the positive electrode active material layer. 【0071】 The positive electrode current collector is not particularly limited as long as it does not induce chemical changes in the all-solid-state battery and has high electronic conductivity. For example, copper, stainless steel, aluminum, nickel, titanium, palladium, calcined carbon, copper or stainless steel surface-treated with carbon, nickel, silver, etc., or aluminum-cadmium alloy may be used as the positive electrode current collector. 【0072】 The positive electrode current collector may have a fine uneven surface or employ a three-dimensional porous structure to strengthen the bonding force with the positive electrode active material layer. As a result, the positive electrode current collector may include various forms such as film, sheet, foil, mesh, net, porous material, foam, and nonwoven fabric. 【0073】 The positive electrode described above can be manufactured by conventional methods. Specifically, it can be manufactured by mixing a positive electrode active material, a conductive material, and a binder in an organic solvent to produce a composition for forming a positive electrode active material layer, which is then coated onto a positive electrode current collector and dried, and then selectively compress-molded onto the current collector to improve electrode density. In this case, it is preferable to use an organic solvent that can uniformly disperse the positive electrode active material, binder, and conductive material and evaporates easily. Examples include acetonitrile, methanol, ethanol, tetrahydrofuran, water, and isopropyl alcohol. 【0074】 In the present invention, the negative electrode included in the all-solid-state battery includes a negative electrode active material layer, and the negative electrode active material layer may be formed on one side of the negative electrode current collector. 【0075】 The negative electrode active material is lithium (Li + The material may include a substance that can be reversibly intercalated or deintercalated, a substance that can reversibly form a lithium-containing compound by reacting with lithium ions, or a lithium metal or lithium alloy. 【0076】 The aforementioned lithium ion (Li +The material that can reversibly insert or remove the lithium ion (Li) may be, for example, crystalline carbon, amorphous carbon, or a mixture thereof. + A substance that can reversibly form a lithium-containing compound by reacting with ) may be, for example, tin oxide, titanium nitrate, or silicon. The lithium alloy may be, for example, an alloy of lithium (Li) and a metal selected from the group consisting of sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), francium (Fr), beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), radium (Ra), aluminum (Al), and tin (Sn). 【0077】 Preferably, the negative electrode active material may be lithium metal, and specifically, it may be in the form of a lithium metal thin film or lithium metal powder. 【0078】 The negative electrode active material may be present in an amount of 40 to 80% by weight based on the total weight of the negative electrode active material layer. Specifically, the content of the negative electrode active material may be 40% by weight or more, or 50% by weight or more, or 70% by weight or less, or 80% by weight or less. If the content of the negative electrode active material is less than 40% by weight, the connectivity between the wet negative electrode active material layer and the dry negative electrode active material layer may be insufficient, and if it exceeds 80% by weight, the mass transfer resistance may increase. 【0079】 Furthermore, the binder is as described above for the positive electrode active material layer. 【0080】 Furthermore, the conductive material is as described above for the positive electrode active material layer. 【0081】 Furthermore, the negative electrode current collector is not particularly limited as long as it does not induce a chemical change in the battery and is conductive. For example, the negative electrode current collector may be made of copper, stainless steel, aluminum, nickel, titanium, calcined carbon, copper or stainless steel surface-treated with carbon, nickel, titanium, silver, etc., or aluminum-cadmium alloy. Also, similar to the positive electrode current collector, the negative electrode current collector may be made of various forms such as films, sheets, foils, nets, porous materials, foams, or nonwoven fabrics with fine irregularities formed on their surface. 【0082】 The method for manufacturing the negative electrode is not particularly limited, and the negative electrode active material layer may be formed on the negative electrode current collector using a layer or film formation method commonly used in the industry. For example, methods such as crimping, coating, and vapor deposition may be used. Furthermore, the negative electrode of the present invention is also included in the case where a metallic lithium thin film is formed on a metal plate by initial charging after the battery has been assembled without a lithium thin film on the negative electrode current collector. 【0083】 Battery module Furthermore, the present invention provides a battery module including the all-solid-state battery as a unit battery, a battery pack including the battery module, and a device including the battery pack as a power source. 【0084】 Specific examples of the aforementioned devices include, but are not limited to, power tools powered by battery-powered motors; electric vehicles including electric vehicles (EVs), hybrid electric vehicles (HEVs), and plug-in hybrid electric vehicles (PHEVs); electric two-wheeled vehicles including electric bicycles (E-bikes) and electric scooters; electric golf carts; and power storage systems. 【0085】 The following are preferred embodiments to aid in understanding the present invention. These embodiments are illustrative of the present invention, and it will be apparent to those skilled in the art that various changes and modifications are possible within the scope of the present invention and the technical concept, and that such variations and modifications fall within the scope of the appended claims. 【0086】 In the following examples and comparative examples, polymer solid electrolytes were prepared according to the compositions listed in Table 1 below. 【0087】 [Table 1] 【0088】 Example 1 Aquivion-Li (Merck, 25% aqueous solution, CAS No. 1687740-67-5) was added as a single-ionic conductor to a liquid-phase polyethylene glycol-polyhedral oligomeric silsesquioxane (PEG-POSS), and then mixed to obtain a solution for forming a polymer solid electrolyte. At this time, the weight ratio of the single-ionic conductor to PEG-POSS was set to 1:2. Aquivion-Li is a single-ionic conductor having a structure in which the hydrogen of the sulfonic acid group (-SO3H) contained in the perfluorosulfonic acid polymer is replaced by a lithium cation (Li+). 【0089】 The polymer solid electrolyte forming solution was applied onto a SUS foil using a doctor blade to form a coating film. 【0090】 Subsequently, the polymer solid electrolyte was produced by heat treatment using vacuum drying at 100°C for one day. 【0091】 Example 2 A polymer solid electrolyte was prepared in the same manner as in Example 1, except that LiTFSI, a lithium salt, was uniformly mixed with liquid-phase PEG-POSS in a weight ratio of 1:0.4 to dissociate the lithium salt, and then SiC was added. 【0092】 Example 3 A polymer solid electrolyte was prepared in the same manner as in Example 2, except that the weight ratio of SiC to liquid-phase PEG-POSS was set to 1:1. 【0093】 Comparative Example 1 The procedure was carried out in the same manner as in Example 1, except that liquid-phase PEG-POSS was not used and drying was not performed, to obtain a liquid-phase electrolyte in the form of a SiC solution. The Aquivion-Li (Merck, 25% aqueous solution) used as the SiC is itself in an aqueous solution state, and therefore becomes a liquid-phase electrolyte without undergoing a drying process. 【0094】 Comparative Example 2 A solid electrolyte was obtained by the same procedure as in Example 1, except that liquid-phase PEG-POSS was not used. 【0095】 Comparative Example 3 A polymer solid electrolyte was prepared in the same manner as in Example 2, except that the weight ratio of SiC to liquid-phase PEG-POSS was set to 1:3. 【0096】 Experimental Example 1: Evaluation of the physical properties of polymer solid electrolytes The polymer solid electrolytes produced in the examples and comparative examples were tested for ionic conductivity and film state using the methods described below, and the results are shown in Table 2. 【0097】 (1) Ionic conductivity 1.7671cm 2 A coin cell was manufactured by punching out the polymer solid electrolyte into a circular shape and placing the punched-out polymer solid electrolyte between two pieces of stainless steel (SUS). An AC voltage was applied to the coin cell at room temperature, and the application conditions were set to an amplitude range of 500 kHz to 20 MHz. The impedance was measured using a VMP3 from BioLogic. The resistance (Rb) of the polymer solid electrolyte was determined from the intersection points where the semicircles and straight lines of the measured impedance trajectory intersected with the actual contraction using Equation 1 below, and the ionic conductivity (σ) was calculated from the area (A) and thickness (t) of the polymer solid electrolyte. 【0098】 【number】 【0099】 σ: Ionic conductivity of polymer solid electrolytes Rb:Resistance A: The breadth of polymer solid electrolytes t: Thickness of polymer solid electrolyte 【0100】 (2) Membrane state The membrane state of the polymer solid electrolyte was determined by visual observation to determine whether or not it was formed as a film. 【0101】 [Table 2] 【0102】 As shown in Table 2 above, Example 1 was able to obtain a polymer solid electrolyte having a solid phase film structure and excellent ionic conductivity by using a single ion conductor and liquid-phase PEG-POSS as raw materials and undergoing a drying process. 【0103】 Examples 2 and 3 are the same as Example 1 but with the addition of a lithium salt, and it can be seen that the ionic conductivity was improved by the lithium salt. 【0104】 On the other hand, in Comparative Example 1, a liquid-phase electrolyte was produced simply by coating a single-ion conductor that was itself in an aqueous solution state. 【0105】 Furthermore, Comparative Example 2 was obtained by adding a drying step to Comparative Example 1, and although a solid-phase film was obtained, it was found to have low ionic conductivity. 【0106】 In Comparative Example 3, when an excessive amount of liquid-phase PEG-POSS was used compared to the single-ion conductor, a liquid-phase electrolyte was produced, and phase separation was also observed. 【0107】 Thus, since single-ion conductors themselves contain Li ions as a polymer solid electrolyte, they can exhibit the appropriate ionic conductivity required for electrolytes. Furthermore, when liquid-phase PEG-POSS is added in the appropriate weight ratio, the fluidity of the polymer chains improves, and the ionic conductivity is enhanced. In addition, the ionic conductivity can be further improved by adding lithium salts. 【0108】 Although the present invention has been described above with limited embodiments and drawings, the present invention is not limited thereto, and it is obvious that various modifications and variations can be made by persons with ordinary skill in the art to which the present invention pertains, within the equivalent scope of the technical concept of the present invention and the claims described below. [Explanation of symbols] 【0109】 1: Polymer solid electrolyte 10: Single-ion conductor (SIC) 20: Liquid-phase polyhedral oligomeric silsesquioxane (POSS)

Claims

[Claim 1] A polymer solid electrolyte comprising a single-ionic conductor (SIC) and a liquid-phase polyhedral oligomeric silsesquioxane (POSS). [Claim 2] The polymer solid electrolyte according to claim 1, wherein the liquid-phase polyhedral oligomeric silsesquioxane is contained in an internal space formed by polymer chains contained in the single-ion conductor. [Claim 3] The single-ion conductor comprises a perfluorosulfonic acid (PFSA) polymer, and the perfluorosulfonic acid polymer contains sulfonic acid groups (-SO ３ The hydrogen of H) is a lithium cation (Li ＋ The polymer solid electrolyte according to claim 1, having a structure substituted with ). [Claim 4] The polymer solid electrolyte further contains a lithium salt, The lithium salt is (CF ３ SO ２ ), ２ NLi (LiTFSI), (FSO ２ ), ２ NLi (LiFSI), LiNO ３ , LiOH, LiCl, LiBr, LiI, LiClO ４ , LiBF ４ , LiB １０ Cl １０ , LiPF ６ , LiCF ３ SO ３ , LiCF ３ CO ２ , LiAsF ６ , LiSbF ６ , LiAlCl ４ , CH ３ SO ３ Li, CF ３ SO ３ Li, LiSCN and LiC (CF ３ SO ２ ), ３ The polymer solid electrolyte according to claim 1, which contains one or more selected from the group consisting of [Claim 5] The polymer solid electrolyte according to claim 1, wherein the weight ratio of the single-ion conductor to the liquid-phase polyhedral oligomeric silsesquioxane is 1:1 to 1:

2. [Claim 6] The polymer solid electrolyte according to claim 1, wherein the polymer solid electrolyte is in the form of a free-standing film. [Claim 7] The polymer solid electrolyte according to claim 1, wherein the polymer solid electrolyte further comprises a liquid electrolyte. [Claim 8] (S1) A step of forming a polymer solid electrolyte solution containing a single ion conductor (SIC) and a liquid-phase polyhedral oligomeric silsesquioxane (POSS); (S2) The step of applying the polymer solid electrolyte forming solution onto a substrate to form a coating film; and A method for producing a polymer solid electrolyte, comprising the step of (S3) drying the coated film. [Claim 9] The method for producing a polymer solid electrolyte according to claim 8, wherein a lithium salt is further added in the step of forming the polymer solid electrolyte solution. [Claim 10] An all-solid-state battery comprising a polymer solid electrolyte according to any one of claims 1 to 7. [Claim 11] The all-solid-state battery includes a positive electrode layer, a negative electrode layer, and a solid electrolyte layer formed between the positive electrode layer and the negative electrode layer. The all-solid-state battery according to claim 10, wherein at least one of the positive electrode layer, negative electrode layer, and solid electrolyte layer includes the polymer solid electrolyte. [Claim 12] A battery module comprising the all-solid-state battery described in claim 10.

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