Anion receptor and electrolyte containing same

Abstract

An anion receptor compound for a lithium-ion battery and an electrolyte including same, according to the present invention, include an anion receptor having an amino group substituted with an electron-withdrawing functional group or having a nitrogen atom introduced into the ring, and exhibit a very high ionic conductivity and cation transference number in a lithium-ion battery. In addition, by forming a solid electrode interface (SEI) film on the surface of an electrode, damage to the surface of the electrode caused by degradation products resulting from the use of an electrolyte is suppressed, thereby increasing the lifespan of the electrode, and the generation of strong acids such as HF due to decomposition of a lithium salt contained in the electrolyte is suppressed, thereby increasing the lifespan of the battery and a lithium-ion capacitor during charging and discharging, and reinforcing battery safety.

Description

Anion receptors and electrolytes containing the same

[0001] The present invention relates to novel anion acceptors and non-aqueous liquid electrolytes and gel-type or solid polymer electrolytes containing the same, and more specifically, to anion acceptors in which an amine group substituted with an electron-withdrawing group or a nitrogen atom within a ring is introduced.

[0002] Due to global warming and the depletion of fossil fuels, the development of high-output, high-capacity power storage devices is required to meet the demand for power sources for zero-emission, eco-friendly electric vehicles and for information and communication devices and electronic products with increasingly complex applications, such as smartphones. Various studies are underway to improve lithium-ion batteries as such power sources. Among the component materials that determine the performance of these power sources, the electrolyte significantly affects not only itself but also the performance of the electrode. If the electrolyte used in conventional secondary batteries is used as is, there is a problem where electrochemical stability rapidly declines due to the degradation of the electrode and electrolyte following prolonged charging and discharging. Furthermore, in the case of electric vehicles equipped with large-capacity, high-capacity battery packs, the risk of fire caused by ignition resulting from physical damage to the battery or damage caused by overcharging or over-discharging is emerging as a major social issue. As part of efforts to overcome these problems with electrolytes, research on anion acceptors is underway, and anion acceptors enhance anion stability through Lewis acid-salt interactions. Anion acceptors are compounds containing electron-deficient atoms (such as nitrogen or boron) that facilitate the movement of lithium cations by coordinating electron-rich anions around them, thereby hindering the binding of anions and lithium cations into ion pairs. The first known compound as an anion acceptor is an aza-ether composed of a cyclic or linear amide, in which the nitrogen atom of an amine group substituted by a perfluoroalkylsulfonyl substituent is made electron-deficient, allowing it to interact appropriately with electron-rich anions through Coulomb attraction 143(1996)3825,146(2000)9). (J. Electrochem. Soc.However, these aza-ethers exhibit limited solubility in polar solvents adopted as typical non-aqueous electrolytes, and it has been found that the electrochemical stability window of the electrolyte with added LiCl salt does not meet the 4.0 V required for commercially available cathode materials, and is unstable in LiPF6 (J. Electrochem. Solid-State Lett., 5(2002)A248). That is, LiPF6 is chemically and thermally unstable and is in equilibrium with solid LiF and gaseous PF5 even at room temperature, and the generation of this gaseous product PF5 further tilts the equilibrium toward the formation of PF5.

[0003] LiPF6(s) ↔ LiF(s) + PF5(g)

[0004] In non-aqueous solvents, PF5 tends to initiate a series of reactions, such as ring-opening polymerization or breaking ether bonds composed of atoms with non-covalent electron pairs, such as oxygen or nitrogen. PF5, a strong Lewis acid, attacks electron pairs, and aza ethers are subjected to immediate attack by PF5 because of their high electron density (J. Power Sources, 104(2002)260).

[0005] The present invention provides an anion acceptor having an amine group substituted with an electron-withdrawing functional group or a nitrogen atom within the ring introduced therein, which is applied as an electrolyte, electrolyte additive, or electrode material for a lithium-ion battery to improve the performance of the lithium-ion battery and ensure extremely high safety without the risk of ignition due to damage.

[0006] To resolve the aforementioned conventional problems and achieve the objective, the present invention provides compounds represented by the following chemical formulas 1 to 5 as introduced anion acceptors according to the present invention.

[0007] [Chemical Formula 1]

[0008]

[0009] [Chemical Formula 2]

[0010]

[0011] [Chemical Formula 3]

[0012]

[0013] [Chemical Formula 4]

[0014]

[0015] [In the above chemical formulas 1 to 4, R is -SO2CF3, -SO2F, -CN, -F, -Cl, -COCF3, or -SO2CN.]

[0016] [Chemical Formula 5]

[0017]

[0018] [In the above Chemical Formula 5, R1 and R2 are each -H, -SO2CF3, -SO2F, -CN, -F, -Cl, -COCF3, or -SO2CN, and R1 and R2 do not simultaneously become hydrogen atoms.]

[0019] Furthermore, an electrolyte comprising compounds of the above chemical formulas 1 to 5 is provided.

[0020] Furthermore, an electrolyte is provided composed of a compound of the above chemical formulas 1 to 5 and a compound selected from linear hydrocarbons, linear siloxanes, cyclic siloxanes, and polyalkylene oxide compounds represented by the following chemical formulas 6 to 9.

[0021] [Chemical Formula 6]

[0022]

[0023] In the above chemical formula 6,

[0024] R1 and R2 are each independently hydrogen atoms; or electron-withdrawing functional groups selected from -SO2CF3, -COCF3, -SO2CN and -CN, and R1 and R2 do not simultaneously become hydrogen atoms;

[0025] R3 is a hydrogen atom or a methyl group;

[0026] X is a hydrogen atom, a methyl group, or is;

[0027] n is an integer from 0 to 20.

[0028] [Chemical Formula 7]

[0029]

[0030] In the above chemical formula 7,

[0031] R1 and R2 are each independently hydrogen atoms; or electron-withdrawing functional groups such as -SO2CF3, -CN, -F, -Cl, -COCF3, and -SO2CN, where neither becomes a hydrogen atom;

[0032] R3 is a hydrogen atom or a cyanide group;

[0033] R4 is a hydrogen atom, or is,

[0034] R5 and R6 are each independently a hydrogen atom or a methyl group;

[0035] R7 is independently of each other R7 in Formula 1 an alkyl, alkenyl, alkyl halide, alkenyl halide, alkanol, halogen, hydrogen atom, or hydroxyl group;

[0036] R8 is an alkyl, alkenyl, alkyl halide, or alkenyl halide group, independently of each other with other R8s in Formula 1;

[0037] Y and Z are each independently O, S, CO, OCO, OCOO, or COO;

[0038] n is an integer from 1 to 1000; o, p, q, and t are integers from 0 to 1000 each; and r and s are integers from 0 to 20 each, with a sum of at least 1.

[0039] [Chemical Formula 8]

[0040]

[0041] In the above chemical formula 8,

[0042] R1 and R2 are each independently hydrogen atoms; or electron-withdrawing functional groups such as -SO2CF3, -CN, -F, -Cl, -COCF3, and -SO2CN, where both are not hydrogen atoms;

[0043] R3 is a hydrogen atom or a cyanide group;

[0044] R4 is a hydrogen atom, or is,

[0045] R5 and R6 are each independently a hydrogen atom or a methyl group;

[0046] R7 is independently of each other R7 in Formula 1 an alkyl, alkenyl, alkyl halide, alkenyl halide, alkanol, halogen, hydrogen atom, or hydroxyl group;

[0047] Y and Z are each independently O, S, CO, OCO, OCOO, or COO;

[0048] n is an integer from 1 to 1000; o, p, and q are integers from 0 to 1000 each; and r and s are integers from 0 to 20 each whose sum is at least 1.

[0049] [Chemical Formula 9]

[0050]

[0051] In the above chemical formula 9,

[0052] R1 and R2 are each independently hydrogen atoms; or electron-withdrawing functional groups selected from -SO2CF3, -CN, -F, -Cl, -COCF3, -BF3 and -SO2CN, and R1 and R2 are not simultaneously hydrogen atoms;

[0053] R3 and R4 are each independently alkyl, alkenyl, alkyl halide, alkenyl halide, alkanol, halogen, hydrogen atom, hydroxyl group;

[0054] X is CH3O- or is;

[0055] R3 and X do not become hydrogen atoms at the same time,

[0056] m is an integer from 0 to 20, and

[0057] n is an integer from 1 to 20.

[0058] Meanwhile, the present invention provides an electrolyte comprising a compound of the above chemical formula 1, wherein the electrolyte is characterized by containing 0.01 to 40 weight% of the compound of the above chemical formula 1 with respect to 100 weight% of the total electrolyte.

[0059] Furthermore, the present invention provides an electrolyte characterized by comprising a compound of the above chemical formulas 1 to 5 and a compound selected from linear hydrocarbons, linear siloxanes, cyclic siloxanes, and polyalkylene oxide compounds represented by the above chemical formulas 6 to 9, wherein the electrolyte comprises 0.01 to 40 weight% of the compound of the above chemical formula 1 based on 100 weight% of the total electrolyte.

[0060] The electrolyte of the present invention contains an amine group substituted with an electron-withdrawing functional group or an anion acceptor into which a nitrogen atom within the ring is introduced, and thus has very high ion conductivity and cation transport rate.

[0061] In addition, the electrolyte of the present invention includes an anion acceptor into which a hydrocarbon with a double bond, such as acryl or vinylene, is introduced, thereby forming a Solid Electrode Interface (SEI) film on the electrode surface and suppressing damage to the electrode surface caused by degradation products resulting from the use of the electrolyte, thereby increasing the electrode lifespan.

[0062] In addition, the electrolyte of the present invention includes an amine group substituted with an electron-withdrawing functional group or an anion acceptor into which a nitrogen atom within the ring is introduced, thereby suppressing the generation of strong acids such as HF due to the decomposition of lithium salts contained in the electrolyte upon use, thereby increasing the lifespan of the battery and lithium ion capacitor during charging and discharging and enhancing the safety of the battery.

[0063] Hereinafter, the anion receptor and the electrolyte containing the same according to the present invention described above will be explained in more detail with reference to specific examples and experimental examples.

[0064] The introduced anion acceptor according to the present invention may be represented by a compound represented by the following chemical formulas 1 to 5, and the electrolyte according to the present invention is composed of a compound represented by the following chemical formulas 1 to 5.

[0065] [Chemical Formula 1]

[0066]

[0067] [Chemical Formula 2]

[0068]

[0069] [Chemical Formula 3]

[0070]

[0071] [Chemical Formula 4]

[0072]

[0073] [In the above chemical formulas 1 to 4, R is -SO2CF3, -SO2F, -CN, -F, -Cl, -COCF3, or -SO2CN.]

[0074] [Chemical Formula 5]

[0075]

[0076] [In the above Chemical Formula 5, R1 and R2 are each -H, -SO2CF3, -SO2F, -CN, -F, -Cl, -COCF3, or -SO2CN, and R1 and R2 do not simultaneously become hydrogen atoms.]

[0077] The electrolyte according to the present invention may be composed of a compound of Formula 1 to 5 and a compound selected from linear hydrocarbons, linear siloxanes, cyclic siloxanes, and polyalkylene oxide compounds represented by Formulas 6 to 9 below.

[0078] [Chemical Formula 6]

[0079]

[0080] In the above chemical formula 6,

[0081] R1 and R2 are each independently hydrogen atoms; or electron-withdrawing functional groups selected from -SO2CF3, -COCF3, -SO2CN and -CN, and R1 and R2 do not simultaneously become hydrogen atoms;

[0082] R3 is a hydrogen atom or a methyl group;

[0083] X is a hydrogen atom, a methyl group, or is;

[0084] n is an integer from 0 to 20.

[0085] [Chemical Formula 7]

[0086]

[0087] In the above chemical formula 7,

[0088] R1 and R2 are each independently hydrogen atoms; or electron-withdrawing functional groups such as -SO2CF3, -CN, -F, -Cl, -COCF3, and -SO2CN, where neither becomes a hydrogen atom;

[0089] R3 is a hydrogen atom or a cyanide group;

[0090] R4 is a hydrogen atom, or is,

[0091] R5 and R6 are each independently a hydrogen atom or a methyl group;

[0092] R7 is independently of each other R7 in Formula 1 an alkyl, alkenyl, alkyl halide, alkenyl halide, alkanol, halogen, hydrogen atom, or hydroxyl group;

[0093] R8 is an alkyl, alkenyl, alkyl halide, or alkenyl halide group, independently of each other with other R8s in Formula 1;

[0094] Y and Z are each independently O, S, CO, OCO, OCOO, or COO;

[0095] n is an integer from 1 to 1000; o, p, q, and t are integers from 0 to 1000 each; and r and s are integers from 0 to 20 each, with a sum of at least 1.

[0096] [Chemical Formula 8]

[0097]

[0098] In the above chemical formula 8,

[0099] R1 and R2 are each independently hydrogen atoms; or electron-withdrawing functional groups such as -SO2CF3, -CN, -F, -Cl, -COCF3, and -SO2CN, where both are not hydrogen atoms;

[0100] R3 is a hydrogen atom or a cyanide group;

[0101] R4 is a hydrogen atom, or is,

[0102] R5 and R6 are each independently a hydrogen atom or a methyl group;

[0103] R7 is independently of each other R7 in Formula 1 an alkyl, alkenyl, alkyl halide, alkenyl halide, alkanol, halogen, hydrogen atom, or hydroxyl group;

[0104] Y and Z are each independently O, S, CO, OCO, OCOO, or COO;

[0105] n is an integer from 1 to 1000; o, p, and q are integers from 0 to 1000 each; and r and s are integers from 0 to 20 each whose sum is at least 1.

[0106] [Chemical Formula 9]

[0107]

[0108] In the above chemical formula 9,

[0109] R1 and R2 are each independently hydrogen atoms; or electron-withdrawing functional groups selected from -SO2CF3, -CN, -F, -Cl, -COCF3, -BF3 and -SO2CN, and R1 and R2 are not simultaneously hydrogen atoms;

[0110] R3 and R4 are each independently alkyl, alkenyl, alkyl halide, alkenyl halide, alkanol, halogen, hydrogen atom, hydroxyl group;

[0111] X is CH3O- or is;

[0112] R3 and X do not become hydrogen atoms at the same time,

[0113] m is an integer from 0 to 20, and

[0114] n is an integer from 1 to 20.

[0115]

[0116] Meanwhile, it is preferable that the electrolyte according to the present invention contains 0.01 to 40 weight percent of the compound of Formula 1 with respect to 100 weight percent of the total electrolyte.

[0117]

[0118] That is, the anion acceptor according to the present invention is a compound in which an electron-withdrawing functional group is substituted on an amine group or a nitrogen atom within a ring. The anion acceptor of the present invention can increase ion conductivity by facilitating the movement of lithium cations by taking a nitrogen atom, which is an electron-deficient atom included in the electrolyte, and coordinating an electron-rich anion, thereby hindering the binding of anion and lithium cation into ion pairs. Additionally, since an electron-withdrawing functional group is substituted on the nitrogen atom, the movement of cations is facilitated more easily, and at the same time, when employed in a lithium-ion battery, electrochemical stability is increased, thereby improving the lifespan characteristics of the electrode.

[0119] More specifically, the amine group or the nitrogen atom within the ring substituted with an electron-withdrawing functional group is used to increase electronegativity and cation mobility by promoting the dissociation of alkali metal salts. That is, the amine group or the nitrogen within the ring becomes electron-deficient due to electron-withdrawing functional groups such as -SO2CF3, -CN, -F, -Cl, -COCF3, and -SO2CN, thereby forming an electrically neutral complex with the anionic species of the alkali metal salt, which promotes the dissociation of the alkali metal salt.

[0120] In addition, by positioning the nitrogen atoms of the amine group substituted with electron-withdrawing functional groups and the nitrogen atoms within the ring only at the ends of the hydrocarbon chain, electrochemical instability caused by the presence of vulnerable nitrogen atoms in the middle of the complex, instability of the lithium salt (especially LiPF6), and steric hindrance can be resolved. Furthermore, since the center of the nitrogen is more exposed and bulky anions can easily access it, the dissociation of the lithium salt is enhanced and the cation mobility is increased, thereby achieving high ionic conductivity.

[0121] An electrolyte according to one embodiment of the present invention comprises 0.01 to 40 weight percent of the compounds of Formulas 1 to 5 with respect to 100 weight percent of the electrolyte. Here, if included in an amount less than 0.01 weight percent, the ionic conductivity is not improved, and if included in an amount greater than 40 weight percent, the ionic conductivity of the electrolyte is actually lowered. Therefore, to increase such ionic conductivity, it may more preferably be included in an amount of 0.1 to 20 weight percent. Formulas 1 to 5 of the present invention may be synthesized by known methods, and as an example thereof, they may be represented by the following Reaction Scheme 1, but are not limited thereto.

[0122] [Reaction Equation 1]

[0123]

[0124] The present invention provides an electrolyte comprising an anion acceptor represented by the above chemical formulas 1 to 5, and the electrolyte of the present invention can be used in a lithium-ion battery, but preferably can be used as a non-aqueous liquid electrolyte, a gel-type polymer electrolyte, and a solid polymer electrolyte.

[0125] Specifically, one embodiment of the electrolyte of the present invention is,

[0126] (i) anion receptors of the above chemical formulas 1 to 5;

[0127] (ii) non-aqueous solvents; and

[0128] (iii) It may be a non-aqueous liquid electrolyte composed of a substance containing alkali metal ions.

[0129] Another embodiment of the present invention is,

[0130] (i) anion receptors of the above chemical formulas 1 to 5;

[0131] (ii) polymer support;

[0132] (iii) non-aqueous solvents; and

[0133] (iv) It may be a gel-type polymer electrolyte composed of an alkali metal ion-containing material.

[0134] And another embodiment of the present invention is,

[0135] (i) anion receptors of the above chemical formulas 1 to 5;

[0136] (ii) a polymer compound or a crosslinkable polymer compound selected from network, comb-shaped, and branched polymer compounds; and

[0137] (iii) It may be a solid polymer electrolyte composed of a material containing alkali metal ions.

[0138] A solid polymer electrolyte according to one embodiment of the present invention may further include one or more compounds selected from polyalkylene glycol dialkyl ether and non-aqueous solvents.

[0139] At this time, the non-aqueous solvent used in the above electrolyte may be ethylene carbonate (EC), dimethyl carbonate (DMC), diethyl carbonate (DEC), propylene carbonate, ether, organic carbonate, lactone, formate, ester, sulfonate, nitrite, oxazolidinone, tetrahydrofuran, 2-methyltetrahydrofuran, 4-methyl-1,3-dioxolan, 1,3-dioxolan, 1,2-dimethoxyethane, dimethoxymethane, γ-butyrolactone, methyl formate, sulfolane, acetonitrile, 3-methyl-2-oxazolidinone, N-methyl-2-pyrrolidinone, or a mixture thereof; The above alkali metal ion-containing material may be LiSO3CF3, LiCOOC2F5, LiN(SO2CF3)2, LIPO2F3, LiDFOB, LiC(SO2CF3)3, LiClO4, LiAsF6, LiBF4, LiPF6, LiSbF6, LiI, LiBr, LiCl, or a mixture thereof, and is not particularly limited.

[0140] In addition, the polymer support used in the above gel-type polymer electrolyte is not particularly limited, but a polyacrylonitrile (PAN)-based polymer or a polyvinylidene fluoride (PVDF)-hexafluoropropylene-based polymer may be used.

[0141] In addition, the network, comb-like, or branched polymer compounds used in the above-mentioned solid polymer electrolyte are not particularly limited, but may be composed of flexible inorganic polymers or linear polyethers, and as for the crosslinkable polymer compounds, may be those having a flexible inorganic polymer or linear polyether main chain as a basic framework and having functional groups such as acrylic, epoxy, trimethylsilyl, silanol, vinylmethyl, or divinyl monomethyl introduced at the ends.

[0142] In this case, the flexible inorganic polymer is preferably a polysiloxane or a polyphosphazene, and the linear polyether is preferably a polyalkylene oxide. Examples of the crosslinkable polymer compound include bisphenol A ethoxylate dimethacrylate of Formula 10 below or TA-10 of Formula 11 below disclosed in Korean Registered Patent No. 10-0419864:

[0143] [Chemical Formula 10]

[0144]

[0145] [Chemical Formula 11]

[0146]

[0147] The polyalkylene glycol dialkyl ether or non-aqueous solvent that may be included in the above solid polymer electrolyte acts as a plasticizer, such as the anion acceptor of the present invention. Examples of polyalkylene glycol dialkyl ethers include polyethylene glycol dimethyl ether (PEGDME), polyethylene glycol diethyl ether, polyethylene glycol dipropyl ether, polyethylene glycol dibutyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol dimethyl ether, polypropylene glycol diglycidyl ether, polypropylene glycol / polyethylene glycol copolymers with dibutyl ether terminals, or polyethylene glycol / polypropylene glycol / polyethylene glycol block copolymers with dibutyl ether terminals.

[0148] In addition, if the above-mentioned solid polymer electrolyte includes a crosslinkable polymer compound, it further includes a curing initiator. In this case, the curing initiator may be a photocuring initiator, a thermocuring initiator, or a mixture thereof, wherein the photocuring initiator may be dimethylphenylacetophenone (DMPA), t-butylperoxypivalate, ethyl benzoin ether, isopropyl benzoin ether, α-methyl benzoin ethyl ether, benzoin phenyl ether, α-acyloxime ester, α,α-diethoxyacetophenone, 1,1-dichloroacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexylphenyl ketone, anthraquinone, thioxantone, isopropylthioxantone, chlorothioxantone, benzophenone, p-chlorobenzophenone, benzyl benzoate, benzoyl benzoate, Michler's ketone, or a mixture thereof. The above-mentioned thermosetting initiator may use an azoisobutylonitrile-based compound, a peroxide-based compound, or a mixture thereof.

[0149] In the electrolyte of the present invention, it is preferable that the anion acceptor is contained in an amount of 0.01 to 40 weight% of the total composition, and the alkali metal ion-containing substance is contained in an amount of 3 to 60 weight%.

[0150] In the gel-type polymer electrolyte of the present invention, it is preferable to contain 5 to 40 weight percent of the polymer support.

[0151] In the solid polymer electrolyte of the present invention, it is preferable to contain 10 to 95 weight% of a polymer compound selected from the network, comb-shaped, and branched polymer compounds or a crosslinkable polymer compound, and 0.5 to 5 weight% of a curing initiator.

[0152] The above solid polymer electrolyte may contain 10 to 50 weight percent of a compound selected from polyalkylene glycol dialkyl ether and non-aqueous solvents, either alone or in combination of two or more.

[0153] In addition, the present invention provides an alkali metal battery containing the anion acceptor, wherein the alkali metal battery using the liquid or gel-type polymer electrolyte of the present invention comprises a negative electrode, a positive electrode, and a separator, and the battery using the solid polymer electrolyte of the present invention comprises a negative electrode and a positive electrode.

[0154] The negative electrode and positive electrode used in the alkali metal battery of the present invention may be manufactured according to the manufacturing method of the negative electrode and positive electrode used in conventional batteries, and the assembly of the alkali metal battery may also be manufactured by the conventional method of assembling the negative electrode, positive electrode, and electrolyte.

[0155] The above cathode is composed of lithium; lithium alloys such as Li-Al, Li-Si, or Li-Cd; lithium-carbon intercalation compounds; lithium-graphite intercalation compounds; lithium metal oxide intercalation compounds such as LixWO2 or LiMoO2; lithium metal sulfide intercalation compounds such as LiTiS2; mixtures thereof or mixtures thereof and alkali metals.

[0156] The anode is composed of a transition metal oxide, a transition metal chalcogenide, a poly(carbon disulfide) polymer, an organic-disulfide redox polymer, polyaniline, an organic-disulfide / polyaniline complex, or a mixture containing these and oxychloride.

[0157] Hereinafter, an example of the configuration of the alkali metal battery of the present invention is described.

[0158] A primary battery comprising a non-aqueous liquid electrolyte containing an anion acceptor according to the present invention is,

[0159] (i) a cathode containing lithium, a lithium alloy, a lithium-carbon intercalation compound, a lithium-graphite intercalation compound, a lithium metal oxide intercalation compound, a mixture containing these, or an alkali metal;

[0160] (ii) an anode containing a transition metal oxide, a transition metal chalcogenide, a poly(carbon disulfide) polymer, an organic-disulfide redox polymer, a polyaniline, an organic-disulfide / polyaniline complex, and an oxychloride, e.g., an anode containing SO2, CuO, CuS, Ag2CrO4, I2, PbI2, PbS, SOCl2, V2O5, MoO3, MnO2, or polycarbon monofluoride (CF)n;

[0161] (iii) the non-aqueous liquid electrolyte of the present invention as described above; and

[0162] (iv) It is composed of a separator, and the manufacture of the positive and negative electrodes and the assembly of the battery can be done by known methods.

[0163] In addition, a secondary battery comprising a non-aqueous liquid electrolyte containing an anion acceptor according to the present invention is,

[0164] (i) a cathode containing lithium metal or a material capable of reversibly acting as lithium metal, such as lithium; lithium alloys such as Li-Al, Li-Si, Li-Cd, etc.; lithium-carbon intercalation compounds, lithium-graphite intercalation compounds; lithium metal oxide intercalation compounds such as LixWO2 or LiMoO2; or lithium metal sulfide intercalation compounds such as LiTiS2;

[0165] (ii) Li 2.5 V6O 13 , Li 1.2 V2O5, LiCoO2, LiNiO2, LiNi 1-x M x A cathode containing a transition metal oxide capable of intercalating lithium, such as O2 (where M is Co, Mg, Al, or Ti), LiMn2O4, or LiMnO2; a transition metal halide; or a chalcogenide, such as LiNbSe3, LiTiS2, or LiMoS2;

[0166] (iii) the non-aqueous liquid electrolyte of the present invention as described above; and

[0167] (iv) It is composed of a separator, and the manufacture of the positive and negative electrodes and the assembly of the battery can be done by known methods.

[0168] A secondary battery comprising a gel-type polymer electrolyte containing an anion acceptor according to the present invention is composed of the gel-type polymer electrolyte according to the present invention, together with a negative electrode, a positive electrode, and a separator used in a secondary battery composed of the non-aqueous liquid electrolyte.

[0169] A secondary battery comprising a solid polymer electrolyte containing an anion acceptor compound of the present invention may be composed of the solid polymer electrolyte of the present invention together with a negative electrode and a positive electrode used in a secondary battery composed of a non-aqueous liquid electrolyte.

[0170] In addition, the present invention provides a polymer electrolyte thin film using the electrolyte of the present invention.

[0171] A method for manufacturing a gel-type or solid polymer electrolyte thin film containing the components of the present invention is described below.

[0172] First, in the case of a gel-type polymer electrolyte, a non-aqueous solvent, an anion acceptor compound of chemical formulas 1 to 5, and an alkali metal ion-containing substance are placed in a container in an appropriate mixing ratio, and the mixture is stirred with a stirrer to prepare a solution, after which a polymer support is added and mixed together.

[0173] When mixing the polymer support, if necessary, a predetermined amount of heat is applied to melt it to prepare a composition mixture for manufacturing the gel-type polymer electrolyte thin film of the present invention.

[0174] The prepared solution is coated onto a support substrate made of glass or polyethylene, or a commercial Mylar film 13, to an appropriate thickness. Then, the coated substrate is dried, exposed to electron beams, ultraviolet rays, or gamma rays, or heated to induce a curing reaction, thereby forming a thin film.

[0175] Next, in the case of a solid polymer electrolyte, first, an anion acceptor, polyalkylene glycol dialkyl ether, a non-aqueous solvent, and an alkali metal ion-containing substance are placed in a container in an appropriate mixing ratio, and the mixture is stirred with a stirrer to prepare a solution, and then a polymer compound that is network-shaped, branched-shaped, or comb-shaped, or a crosslinkable polymer compound, is added and mixed together.

[0176] When mixing polymer compounds that are network-type, branched-type, or comb-type, a predetermined amount of heat is applied to melt them if necessary. If the polymer compound is crosslinkable, a curing-type initiator is added to this mixture and stirred to prepare a composition mixture for manufacturing the solid polymer electrolyte of the present invention.

[0177] The prepared solution is coated to an appropriate thickness onto a support substrate made of glass or polyethylene, or a commercial Mylar film. Then, the coated substrate is dried, exposed to electron beams, ultraviolet or gamma rays, or heated to induce a curing reaction, thereby forming a thin film.

[0178] Another method for manufacturing a thin film is as follows. A composition mixture is applied onto the support substrate, thickness control spacers are fixed to both ends of the support substrate, and then another support substrate is placed over it. Afterward, a curing reaction is carried out using the curing irradiator or heat source to produce a gel-type or solid polymer electrolyte thin film.

[0179] In addition, the present invention provides a polymer electrolyte thin film, an electrochemical cell, and a lithium ion capacitor manufactured using an electrolyte containing an anion acceptor according to the present invention.

[0180] The present invention will be explained in detail below through examples. However, the examples are merely illustrative of the invention and the present invention is not limited by the following examples.

[0181] [Example 1]

[0182]

[0183] 62.1 g of triflic anhydride was added dropwise under a nitrogen atmosphere to a mixture of 8.2 g of 1H-aziridine and 24.3 g of triethylamine mixed in 100 ml of chloroform at -25°C. The solution was stirred at room temperature for 1 hour, then poured into distilled water, the organic layer was separated, and washed three times with distilled water. Subsequently, the organic extract was dried with anhydrous MgSO4 and filtered. Chloroform was removed under vacuum to obtain the product 1-((trifluoromethyl)sulfonyl)-1H-azirine.

[0184] [Example 2]

[0185]

[0186] 62.1 g of triflic anhydride was added dropwise under a nitrogen atmosphere to a mixture of 13.4 g of 1H-pyrrole and 24.3 g of triethylamine mixed in 100 ml of chloroform at -25°C. The solution was stirred at room temperature for 1 hour, then poured into distilled water, the organic layer was separated, and washed three times with distilled water. Subsequently, the organic extract was dried with anhydrous MgSO4 and filtered. Chloroform was removed under vacuum to obtain the product 1-((trifluoromethyl)sulfonyl)-1H-pyrrole.

[0187] [Example 3]

[0188]

[0189] 62.1 g of triflic anhydride was added dropwise under a nitrogen atmosphere to a mixture of 18.62 g of 1H-azepine and 24.3 g of triethylamine mixed in 100 ml of chloroform at -25°C. The solution was stirred at room temperature for 1 hour, then poured into distilled water, the organic layer was separated, and washed three times with distilled water. Subsequently, the organic extract was dried with anhydrous MgSO4 and filtered. Chloroform was removed under vacuum to obtain the product 1-((trifluoromethyl)sulfonyl)-1H-azepine.

[0190] [Example 4]

[0191]

[0192] 62.1 g of triflic anhydride was added dropwise under a nitrogen atmosphere to a mixture of 35.83 g of 4H-dithieno[3,2-b:2',3'-d]pyrrole and 24.3 g of triethylamine mixed in 100 ml of chloroform at -25°C. The solution was stirred at room temperature for 1 hour, then poured into distilled water, the organic layer was separated, and washed three times with distilled water. Subsequently, the organic extract was dried with anhydrous MgSO4 and filtered. Chloroform was removed under vacuum to obtain the product 4-((trifluoromethyl)sulfonyl)-4H-dithieno[3,2-b:2',3'-d]pyrrole.

[0193] [Example 5]

[0194]

[0195] 62.1 g of triflic anhydride was added dropwise under a nitrogen atmosphere to a mixture of 16.42 g of 1H-pyrrol-1-amine and 24.3 g of triethylamine mixed in 100 ml of chloroform at -25°C. The solution was stirred at room temperature for 1 hour, then poured into distilled water, the organic layer was separated, and washed three times with distilled water. Subsequently, the organic extract was dried with anhydrous MgSO4 and filtered. Chloroform was removed under vacuum to obtain the product 1,1,1-trifluoro-N-(1H-pyrrol-1-yl)methanesulfonamide.

[0196] [Example 6] Preparation of Ion-Conducting Thin Film

[0197] The anion acceptor 1-((trifluoromethyl)sulfonyl)-1H-azirin (0.25 g) prepared in Example 1 was mixed with crosslinking agents: bisphenol A ethoxylate dimethacrylate of Formula 10 (purchased from Aldrich, Mw=1,700, "BIS-15m", 0.25 g), poly(ethylene glycol) dimethyl ether (Mw=350, "PEGDME 300", 0.5 g), and lithium trifluoromethanesulfonimide (Li(CF3SO2)2N, 0.3943 g). Dimethylphenylacetophenone (DMPA, 0.0075 g) was added to this mixture, and the mixture solution was applied to a conductive glass substrate and then exposed to ultraviolet light of a wavelength of 350 nm for 30 minutes under a nitrogen atmosphere. A solid polymer thin film was prepared by this light irradiation.

[0198] [Comparative Example 1] Preparation of a thin film not containing anion acceptors

[0199] A solid polymer thin film was prepared in the same manner as in Example 6 above by setting the composition of the compound used as shown in Table 1 below.

[0200] Crosslinking agent Anion acceptor Compound Plasticizer Lithium salt Initiator Amount Amount Amount Amount Amount Amount Amount Example 6 Bis-15m Example 1 PEGDMELi(CF3SO2)2NDMPA 0.25 g 0.25 g 0.50 g 0.3943 g 0.0075 g Comparative Example 1 Bis-15m--Li(CF3SO2)2NDMPA 0.25 g--0.1270 g 0.0075 g

[0201]

[0202] [Example 7] Ion Conductivity Experiment

[0203] The ionic conductivity of the solid polymer electrolyte thin film and the thin film prepared in Comparative Example 1 was measured using 1-((trifluoromethyl)sulfonyl)-1H-azirin, an anion acceptor synthesized in Example 1 according to the present invention, as in Example 6 above.

[0204] Ionic conductivity was measured by the following method.

[0205] The complex impedance was obtained by applying a solid polymer electrolyte composition onto a band-type conductive glass substrate or lithium-copper foil, photocuring, and sufficient drying, then measuring the AC impedance between the band-type or sandwich-type electrodes under a nitrogen atmosphere, and analyzing the measured values ​​using a frequency response analyzer.

[0206] A band-type electrode was prepared and used by attaching a masking tape with a width of 0.5-2 mm to the center of a conductive glass (ITO) at intervals of about 0.5-2 mm, immersing it in an etching solution to etch it, and then washing and drying it.

[0207] Ionic conductivity was measured using the solid polymer electrolyte thin film of Example 4, prepared with the composition as shown in Table 1 above, in the same manner as above. The results of measuring ionic conductivity at a temperature of 30°C are shown in Table 2 below.

[0208] Ionic conductivity σ (S / cm) Example 66.50 × 10 -5 Comparative Example 14.62 × 10 -6

[0209] As shown in Table 2, it can be seen that the solid polymer electrolyte thin film prepared using the anion acceptor according to the present invention has significantly higher ion conductivity than the solid polymer electrolyte thin film prepared without the anion acceptor, and due to the high ion conductivity, electrochemical batteries and lithium-ion capacitors employing the solid polymer electrolyte thin film according to the present invention can have high efficiency.

[0210]

[0211] [Example 8] Preparation of a lithium-ion polymer battery using a gel-type polymer electrolyte containing anion acceptors

[0212] The anion acceptor prepared in Example 1 was mixed with a crosslinking agent, bisphenol A ethoxylate diacrylate (purchased from Aldrich, Mw=688, "BIS-4", 0.133 g), an organic solvent EC / DMC / DEC (1:1:1, 1M LiPF6) (0.667 g), and t-butyl peroxypivalate (LUPEROX 11M70, 0.004 g).

[0213] A lithium-ion polymer battery, sealed with a polyethylene separator impregnated with the above mixture solution between lithium and nickel metals, was heat-cured in an oven at 80°C for 2 hours.

[0214] A typical 2-electrode electrochemical cell was fabricated. Nickel metal was used as the working electrode, and lithium metal was used as the reference electrode and counter electrode.

[0215] The battery was assembled inside a glove box and manufactured by vacuum sealing using a metal-laminated polyethylene bag.

[0216] [Comparative Example 2] Preparation of a lithium-ion polymer battery using a gel-type polymer electrolyte not containing anion acceptors

[0217] A lithium-ion polymer battery was prepared in the same manner as in Example 8, except that an anion acceptor was not used.

[0218] [Example 9] Electrochemical stability test

[0219] The electrochemical stability of the lithium-ion polymer batteries prepared in Example 8 and Comparative Example 2 of the present invention was evaluated using a potentiostat (EG&G, model 270 A) by cyclic voltamography and linear sweep voltamography. CV was measured at a temperature of 30°C in the range of -0.5V to 6.0V at a potential sweep rate of 5 mV / sec. In contrast to the lithium-ion polymer battery prepared using an electrolyte without an anion acceptor, which deteriorated at a potential around 4.0V, the lithium-ion polymer battery prepared using an electrolyte containing an anion acceptor showed stability without deterioration even at an oxidation potential of 4.9V and exhibited a reversible redox reaction of lithium with respect to the working electrode.

[0220] [Example 10] Preparation of a lithium-ion battery using a liquid electrolyte containing anion acceptors

[0221] The anion acceptor prepared in Example 1 was mixed with the organic solvent EC / DMC / EMC (1:1:1, 1M LiPF6) (1.0 g). A lithium-ion battery was assembled by vacuum sealing a polypropylene separator impregnated with the above mixture solution between a LiCoO2 anode and a graphite carbon cathode in a dry room (humidity: within 3%). The LiCoO2 anode was prepared by coating a mixture of 94 wt.% LiCoO2 (Nippon Chemical Industry), 3 wt.% acetylene black, and 3 wt.% polyvinylidene fluoride (PVDF) onto aluminum foil.

[0222] [Comparative Example 3] Manufacture of a lithium-ion battery using a liquid electrolyte not containing anion acceptors

[0223] A lithium-ion battery was manufactured in the same manner as in Example 10, except that an anion acceptor was not used.

[0224] [Example 11] Experiment on Lithium Cycling Performance and Efficiency of Lithium-Ion Batteries

[0225] The lithium cycling performance and efficiency of the lithium-ion batteries prepared in Example 10 and Comparative Example 3 of the present invention were measured at room temperature using a charge-discharge test apparatus (Maccor 4000). Charging and discharging were performed at 0.2, 0.5, and 1 C. The lithium-ion batteries had a performance of 0.6 mA / cm² relative to the LiCoO2 counter electrode. 2 (Charging), 1.5 mA / cm 2 It was charged and discharged between 3.0 V and 4.2 V with a constant current density of (discharge).

[0226] As a result of comparing the discharge capacity with respect to the number of cycles of lithium-ion battery cells manufactured using an electrolyte containing an anion acceptor of the present invention and an electrolyte not containing additive compounds, except for the first few cycles, the lithium-ion battery using the electrolyte containing an anion acceptor of the present invention showed a higher capacity than the lithium-ion battery using the electrolyte not containing an anion acceptor.

[0227] In addition, the discharge capacity of the battery containing an anion acceptor increased until it reached 20 cycles and then gradually decreased thereafter. However, the capacity of the battery without anion acceptor showed a tendency to decrease significantly as the cycles progressed.

[0228] This result shows that the performance of lithium-ion batteries is improved by the addition of anion acceptors.

[0229]

[0230] [Example 12] Preparation of a lithium-ion capacitor cell using an electrolyte containing an additive compound

[0231] An electrolyte was prepared by mixing the anion acceptor prepared in Example 1 with the organic solvent EC / DMC / EMC (1:1:1, 1M LiPF6) (1.0g).

[0232] Li4Ti5O 12 The anode is 82.5 wt. % 21 Li4Ti5O 12 The cathode was prepared by coating a mixture of 10 wt.% carbon black (DB-100) and 7.5 wt.% polyvinylidene fluoride (PVDF) onto aluminum foil. The cathode was prepared by coating a mixture of 85 wt.% activated carbon, 10 wt.% carbon black (DB-100), and 10 wt.% polyvinylidene fluoride (PVDF) onto aluminum foil. Li4Ti5O in a dry room (humidity: within 3%) 12 A polypropylene separator impregnated with the above mixture solution was inserted between the anode and the activated carbon cathode and vacuum-sealed to assemble the assembly.

[0233]

[0234] [Comparative Example 4] Preparation of a lithium-ion capacitor cell using an electrolyte not containing additive compounds

[0235] A lithium-ion capacitor cell was prepared in the same manner as in Example 12, except that an anion acceptor was not used.

[0236] [Example 13] Lithium cycling performance and efficiency test of a lithium-ion capacitor cell

[0237] The lithium cycling performance and efficiency of the lithium-ion capacitor cells prepared in Example 12 and Comparative Example 4 of the present invention were measured at room temperature using a charge-discharge test apparatus (Maccor 4000). Charging and discharging were performed at 0.2, 0.5, and 1 C. Li4Ti5O 12 0.6 mA / cm² for the counter electrode 2 (Charging), 1.5 mA / cm 2It was charged and discharged between 1.5 V and 3.5 V with a constant current density of (discharge).

[0238] The lithium-ion capacitor cell using the anion acceptor of the present invention exhibited a higher capacity than the lithium-ion capacitor cell using an electrolyte that does not contain an anion acceptor, and showed significantly superior stability.

Claims

1. As an introduced anion acceptor, a compound represented by the following chemical formulas 1 to 5. [Chemical Formula 1] [Chemical Formula 2] [Chemical Formula 3] [Chemical Formula 4] [In the above chemical formulas 1 to 4, R is -SO2CF3, -SO2F, -CN, -F, -Cl, -COCF3, or -SO2CN.] [Chemical Formula 5] [In the above Chemical Formula 5, R1 and R2 are each -H, -SO2CF3, -SO2F, -CN, -F, -Cl, -COCF3, or -SO2CN, and R1 and R2 do not simultaneously become hydrogen atoms.] or it is -SO2CN.] 2. An electrolyte comprising the compound of claim 1.

3. In Paragraph 2, An electrolyte composed of the compound of claim 1 and a compound selected from linear hydrocarbons, linear siloxanes, cyclic siloxanes, and polyalkylene oxide compounds represented by the following chemical formulas 6 to 9. [Chemical Formula 6] In the above chemical formula 6, R1 and R2 are each independently hydrogen atoms; or electron-withdrawing functional groups selected from -SO2CF3, -COCF3, -SO2CN and -CN, and R1 and R2 do not simultaneously become hydrogen atoms; R3 is a hydrogen atom or a methyl group; X is a hydrogen atom, a methyl group, or is; n is an integer from 0 to 20. [Chemical Formula 7] In the above chemical formula 7, R1 and R2 are each independently hydrogen atoms; or electron-withdrawing functional groups such as -SO2CF3, -CN, -F, -Cl, -COCF3, and -SO2CN, where neither becomes a hydrogen atom; R3 is a hydrogen atom or a cyanide group; R4 is a hydrogen atom, or is, R5 and R6 are each independently a hydrogen atom or a methyl group; R7 is independently of each other R7 in Formula 1 an alkyl, alkenyl, alkyl halide, alkenyl halide, alkanol, halogen, hydrogen atom, or hydroxyl group; R8 is an alkyl, alkenyl, alkyl halide, or alkenyl halide group, independently of each other with other R8s in Formula 1; Y and Z are each independently O, S, CO, OCO, OCOO, or COO; n is an integer from 1 to 1,000; o, p, q, and t are integers from 0 to 1,000 each; and r and s are integers from 0 to 20 each, with a sum of at least 1. [Chemical Formula 8] In the above chemical formula 8, R1 and R2 are each independently hydrogen atoms; or electron-withdrawing functional groups such as -SO2CF3, -CN, -F, -Cl, -COCF3, and -SO2CN, where both are not hydrogen atoms; R3 is a hydrogen atom or a cyanide group; R4 is a hydrogen atom, or is, R5 and R6 are each independently a hydrogen atom or a methyl group; R7 is independently of each other R7 in Formula 1 an alkyl, alkenyl, alkyl halide, alkenyl halide, alkanol, halogen, hydrogen atom, or hydroxyl group; Y and Z are each independently O, S, CO, OCO, OCOO, or COO; n is an integer from 1 to 1000; o, p, and q are integers from 0 to 1000 each; and r and s are integers from 0 to 20 each whose sum is at least 1. [Chemical Formula 9] In the above chemical formula 9, R1 and R2 are each independently hydrogen atoms; or electron-withdrawing functional groups selected from -SO2CF3, -CN, -F, -Cl, -COCF3, -BF3 and -SO2CN, and R1 and R2 are not simultaneously hydrogen atoms; R3 and R4 are each independently alkyl, alkenyl, alkyl halide, alkenyl halide, alkanol, halogen, hydrogen atom, hydroxyl group; X is CH3O- or is; R3 and X do not become hydrogen atoms at the same time, m is an integer from 0 to 20, and n is an integer from 1 to 20.

4. In Paragraph 2 or 3, An electrolyte comprising the compound of Formula 1 of Claim 1, characterized in that the compound of Formula 1 is contained in an amount of 0.01 to 40 weight% with respect to 100 weight% of the total electrolyte.

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