Composition for forming gel polymer electrolyte, gel polymer electrolyte, and lithium secondary battery comprising same

Abstract

A composition for forming a gel polymer electrolyte according to embodiments of the present invention comprises: a lithium salt; an organic solvent; a compound represented by chemical formula 1; and polyvinyl alcohol substituted with a nitrile group. A gel polymer electrolyte prepared from the composition for forming a gel polymer electrolyte can have improved flame retardancy.

Description

Composition for forming a gel polymer electrolyte, gel polymer electrolyte, and a lithium secondary battery comprising the same

[0001] The present invention relates to a composition for forming a gel polymer electrolyte, a gel polymer electrolyte, and a lithium secondary battery comprising the same.

[0002] Rechargeable batteries are batteries capable of repeated charging and discharging, and with the advancement of the information and communication and display industries, they are widely applied as power sources for portable electronic communication devices such as camcorders, mobile phones, and laptop PCs. Furthermore, recently, battery packs containing rechargeable batteries are being developed and applied as power sources for eco-friendly vehicles, such as hybrid cars.

[0003] Examples of secondary batteries include secondary batteries, nickel-cadmium batteries, and nickel-hydrogen batteries; among these, secondary batteries are being actively developed and applied due to their high operating voltage and energy density per unit weight, as well as advantages in charging speed and weight reduction.

[0004] For example, a secondary battery may include an electrode assembly comprising a positive electrode, a negative electrode, and a separator, and an electrolyte impregnating the electrode assembly. The secondary battery may further include an outer casing, for example, in the form of a pouch, that accommodates the electrode assembly and the electrolyte.

[0005] Meanwhile, during repeated charging and discharging of secondary batteries, structural deformation of the lithium metal oxide and side reactions of the electrolyte may occur. In this case, the lifespan characteristics of the secondary battery (e.g., capacity retention rate) may deteriorate.

[0006] In particular, secondary batteries are subjected to high-temperature environments during repeated charging and discharging and overcharging. In this case, the aforementioned problems are accelerated, leading to battery expansion (increase in internal battery gas, increase in battery thickness), increased internal resistance of the battery, and deterioration of battery life characteristics.

[0007] One objective of the present invention is to provide a composition for forming a gel polymer electrolyte with improved stability and electrical properties.

[0008] One objective of the present invention is to provide a gel polymer electrolyte with improved stability and electrical properties.

[0009] One objective of the present invention is to provide a secondary battery with improved stability and electrical characteristics.

[0010] An electrolyte for a secondary battery according to exemplary embodiments of the present invention comprises a composition for forming a gel polymer electrolyte comprising a lithium salt, an organic solvent, a compound represented by the following chemical formula 1, and a polyvinyl alcohol substituted with a nitrile group.

[0011] [Chemical Formula 1]

[0012]

[0013] In the above chemical formula 1, R1, R2, R3, or R4 are independently single bonds or alkylene groups having 1 to 5 carbon atoms.

[0014] L is a single bond, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, or an aromatic hydrocarbon group having 6 to 20 carbon atoms.

[0015] In some embodiments, the compound represented by Formula 1 may include at least one of the compounds represented by Formulas 2 to 4 below.

[0016] [Chemical Formula 2]

[0017]

[0018] [Chemical Formula 3]

[0019]

[0020] [Chemical Formula 4]

[0021]

[0022] In some embodiments, the compound represented by Formula 1 may be included in an amount of 0.1% to 1% by weight relative to the total weight of the composition.

[0023] In some embodiments, the polyvinyl alcohol substituted with the nitrile group may include a repeating unit represented by the following chemical formula 5 and a repeating unit represented by the following chemical formula 6.

[0024] [Chemical Formula 5]

[0025]

[0026] [Chemical Formula 6]

[0027]

[0028] In the above chemical formula 6, R5 is an alkylene group having 1 to 5 carbon atoms.

[0029] In some embodiments, the molar ratio of the repeating unit represented by the above-described chemical formula 5 and the repeating unit represented by the above-described chemical formula 6 may be 5:95 to 60:40.

[0030] In some embodiments, the polyvinyl alcohol substituted with the nitrile group may be included in an amount of 0.1% to 5% by weight relative to the total weight of the composition.

[0031] In some embodiments, the organic solvent may comprise at least one selected from the group consisting of dimethyl carbonate (DMC), diethyl carbonate (DEC), dipropyl carbonate (DPC), methylpropyl carbonate (MPC), ethylpropyl carbonate (EPC), ethylmethyl carbonate (EMC), ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate (BC), or compounds containing these.

[0032] In some embodiments, the lithium salt is LiPF6, LiClO4, LiBF4, LiFSI, LiTFSI, LiSO3CF3, LiBOB, LiFOB, LiDFOB, LiDFBP, LiTFOP, LiPO2F2, LiCl, LiBr, LiI, LiB10Cl 10 It may include at least one selected from the group consisting of LiCF3SO3, LiCF3CO2, LiAsF6, LiSbF6, LiAlCl4, CH3SO3Li, CF3SO3Li, LiSCN, LiC(CF3SO2)3, or compounds containing these.

[0033] In some embodiments, the composition may gel in the range of 20°C to 30°C.

[0034] Gel polymer electrolytes according to exemplary embodiments are prepared by gelling a composition for forming a gel polymer electrolyte.

[0035] A secondary battery according to exemplary embodiments comprises a positive electrode, a negative electrode opposite to the positive electrode, and the gel polymer electrolyte described above.

[0036] A gel polymer electrolyte prepared with a composition for forming a gel polymer electrolyte according to exemplary embodiments of the present invention may have improved flame retardancy.

[0037] Figure 1 is Fourier Transform Infrared Spectroscopy (FT-IR) data of a gel polymer electrolyte (PVA-CN-DBA gel) prepared by gelling the DBA solution, PVA-CN solution, and composition for forming a gel polymer electrolyte of Example 1.

[0038] Figure 2 is an image of the gel of Example 1 being directly ignited.

[0039] Figure 3 is an image of the gel of Example 1 after ignition for 4 seconds.

[0040] FIG. 4 is a graph showing the cycle-capacity retention rate performance of lithium secondary batteries of Examples 1 to 4 and Comparative Examples 1 to 2 at room temperature (25 ℃).

[0041] Exemplary embodiments of the present invention provide a composition for forming a gel polymer electrolyte comprising a lithium salt, an organic solvent, a compound represented by Formula 1, and a polyvinyl alcohol substituted with a nitrile group. Additionally, exemplary embodiments of the present invention provide a gel polymer electrolyte prepared by gelling the composition for forming a gel polymer electrolyte. Additionally, a secondary battery comprising a gel polymer electrolyte is provided. Accordingly, the lifespan characteristics of the secondary battery can be improved.

[0042] The present disclosure will be described in detail below. However, this is merely illustrative and the present disclosure is not limited to the specific embodiments described illustratively.

[0043] A composition for forming a gel polymer electrolyte according to exemplary embodiments (hereinafter abbreviated as composition for forming an electrolyte) comprises a lithium salt, an organic solvent, a compound represented by the following chemical formula 1, and a polyvinyl alcohol substituted with a nitrile group.

[0044] [Chemical Formula 1]

[0045]

[0046] In the above chemical formula 1, R1, R2, R3, or R4 are independently single bonds or alkylene groups having 1 to 5 carbon atoms.

[0047] L is a single bond, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, or an aromatic hydrocarbon group having 6 to 20 carbon atoms.

[0048] In the present specification, the aliphatic hydrocarbon may be methylene, ethylene, propylene, propenylene, butylene, pentylene, hexylene, heptylene, or octylene.

[0049] In the present specification, the aromatic hydrocarbon may be phenylene, ethylphenylene, biphenylene, or hydroxyphenylene.

[0050] For example, if the compound represented by Chemical Formula 1 contains an aromatic ring, the strength and thermal stability of the gel may be increased due to the aromatic ring.

[0051] For example, the compound represented by Chemical Formula 1 contains boron, so it can improve the flame retardancy of the electrolyte when used in a gel polymer electrolyte. In addition, the compound represented by Chemical Formula 1 contains a hydroxyl group, so it can react with polyvinyl alcohol substituted with a nitrile group included together to function as a crosslinking agent between polyvinyl alcohol chains.

[0052] According to some embodiments, the compound represented by Formula 1 may include at least one of the compounds represented by Formulas 2 to 4 below.

[0053] [Chemical Formula 2]

[0054]

[0055] [Chemical Formula 3]

[0056]

[0057] [Chemical Formula 4]

[0058]

[0059] According to some embodiments, the compound represented by Formula 1 may be included in an amount of 0.01% to 1% by weight relative to the total weight of the composition, specifically 0.05% to 0.8% by weight, and more specifically 0.1% to 0.5% by weight. Within this range, flame retardancy is effectively exhibited, gelation of the electrolyte is facilitated, and electrical conductivity can be improved.

[0060] According to some embodiments, the polyvinyl alcohol substituted with the nitrile group may include a repeating unit represented by the following chemical formula 5 and a repeating unit represented by the following chemical formula 6.

[0061] [Chemical Formula 5]

[0062]

[0063] [Chemical Formula 6]

[0064]

[0065] In the above chemical formula 6, R5 is an alkylene group having 1 to 5 carbon atoms.

[0066] The polyvinyl alcohol substituted with the above nitrile groups exhibits conductivity and can function as a base resin for gel polymer electrolytes. The nitrile groups of Chemical Formula 6 can react with each other to form a cross-linked structure between polyvinyl alcohol chains.

[0067] In addition, the polyvinyl alcohol chains can also react with the compound of Formula 1 at room temperature to form additional cross-linked structures of the polyvinyl alcohol chains, thereby enabling the formation of a gel polymer at room temperature.

[0068] For example, polyvinyl alcohol substituted with nitrile groups can be represented as PVA-CN(Vinylachol-co-3-(vinyloxy)propanenitrile).

[0069] For example, a compound formed by the reaction of a polyvinyl alcohol substituted with a nitrile group and a compound represented by Chemical Formula 1 to form a cross-linked structure can be represented as a PVA-CN-DBA gel.

[0070] According to one embodiment, the molar ratio of the repeating unit represented by the above-described chemical formula 5 and the repeating unit represented by the above-described chemical formula 6 may be 5:95 to 60:40, 10:90 to 50:50, or 20:80 to 40:60. Within the above range, the solubility of the electrolyte may be improved and the crosslinking rate may be increased.

[0071] The polyvinyl alcohol substituted with the nitrile group may be 0.1% to 5% by weight, or 0.5% to 4% by weight, more specifically 1% to 3% by weight, based on the total weight of the composition. Within this range, gelation of the electrolyte is facilitated and electrical conductivity can be improved.

[0072] In exemplary embodiments, the gel polymer electrolyte of the present disclosure may be prepared by gelling the above-described composition for forming a gel polymer electrolyte.

[0073] For example, a gel polymer electrolyte can be formed by reacting a polyvinyl alcohol substituted with a nitrile group and a compound represented by Chemical Formula 1 to form a cross-linked structure.

[0074] In some embodiments, a method for preparing a gel polymer electrolyte by reacting a base copolymer and a compound represented by Formula 1 can be represented, for example, by the following Formula 1 or Formula 2.

[0075] [Formula 1]

[0076]

[0077]

[0078] [Formula 2]

[0079]

[0080] In some embodiments, the organic solvent may comprise at least one selected from the group consisting of dimethyl carbonate (DMC), diethyl carbonate (DEC), dipropyl carbonate (DPC), methylpropyl carbonate (MPC), ethylpropyl carbonate (EPC), ethylmethyl carbonate (EMC), ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate (BC), or compounds containing these.

[0081] According to one embodiment, the organic solvent may include at least one selected from the group consisting of dimethyl carbonate, ethylene carbonate, and ethylmethyl carbonate, and specifically may be an organic solvent of ethylene carbonate, ethylmethyl carbonate, or a mixture thereof.

[0082] The above-mentioned mixed organic solvent of ethylene carbonate and ethylmethyl carbonate may have a volume ratio of 1:1 to 1:10, specifically 1:1 to 1:5, and more specifically 1:2 to 1:3.

[0083] The electrolyte containing the aforementioned organic solvent has improved electrochemical stability, oxidation resistance, and reduction resistance, so decomposition can be minimized during the charging and discharging process of the secondary battery.

[0084] In some embodiments, the lithium salt is LiPF6, LiClO4, LiBF4, LiFSI, LiTFSI, LiSO3CF3, LiBOB, LiFOB, LiDFOB, LiDFBP, LiTFOP, LiPO2F2, LiCl, LiBr, LiI, LiB10Cl 10 It may include at least one selected from the group consisting of LiCF3SO3, LiCF3CO2, LiAsF6, LiSbF6, LiAlCl4, CH3SO3Li, CF3SO3Li, LiSCN, LiC(CF3SO2)3, or compounds containing these.

[0085] According to one embodiment, the lithium salt may include at least one of LiPF6, LiFSI, and LiDFOB.

[0086] The concentration of the lithium salt dissolved in the organic solvent may be 0.5 M to 3 M, specifically 0.8 M to 1.5 M, and more specifically 0.8 M to 1.2 M. Within this range, the concentration of the electrolyte can be appropriately controlled by the lithium salt in the organic solvent, and the crosslinking reaction can be sufficiently carried out.

[0087] Hereinafter, a secondary battery comprising a positive electrode, a negative electrode, and the electrolyte described above will be described.

[0088] For example, the secondary battery may be a lithium-ion battery, a lithium battery, a sodium battery, a zinc battery, a potassium battery, a magnesium battery, a capacitor, a solar cell, or a wind cell. For example, the performance of the electrolyte described above can be efficiently implemented in a lithium battery.

[0089] The anode may include at least one selected from the group consisting of nickel, cobalt, manganese, tin, silicon, and aluminum. For example, an alloy of lithium, nickel, manganese, and cobalt may be used.

[0090] The above cathode may include at least one selected from the group consisting of graphite, silicon, germanium, tin, and antimony.

[0091] For example, the above electrolyte is located between the negative and positive electrodes of a secondary battery, and can form a cross-linked polymer gel electrolyte through a cross-linking reaction in the secondary battery.

[0092] For example, in a secondary battery, the aforementioned electrolyte forms a film on the negative electrode to protect it, thereby reducing the risk of explosion and fire. In addition, by suppressing side reactions between the negative electrode and the electrolyte, the degradation of the negative electrode is prevented, and consequently, lifespan characteristics can be improved.

[0093] For example, the secondary battery according to the invention can have improved lifespan characteristics compared to a lithium secondary battery using a conventional liquid electrolyte.

[0094] Hereinafter, preferred embodiments are presented to aid in understanding the present invention; however, these embodiments are merely illustrative of the invention and are not intended to limit the appended claims. It is obvious to those skilled in the art that various changes and modifications to the embodiments are possible within the scope and spirit of the invention, and that such variations and modifications fall within the scope of the appended claims.

[0095] Preparation Example: Preparation of polyvinyl alcohol substituted with nitrile groups (PVA-CN)

[0096] A PVA aqueous solution was prepared by adding 1.32 g of PVA (Poly(vinyl alcohol)) and 10 mL of distilled water to a 100 mL round flask, and then 10 mL of 3 M NaOH aqueous solution was added and stirred for 10 minutes to prepare a mixed solution.

[0097] A mixture of acrylonitrile (6.37 g, 0.12 mol), tetrabutylammonium bromide (0.484 g, 0.0015 mol), and acetone (20 mL) was added to the prepared mixed solution and reacted at room temperature (25 ℃) for 6 hours. After the reaction was completed, the polymer solution was precipitated in distilled water and dried in a vacuum oven at 50 ℃ to prepare PVA-CN.

[0098] Example 1

[0099] (1) Preparation of gel polymer electrolyte (PVA-CN-DBA gel)

[0100] An electrolyte was prepared by adding and mixing LiPF6 to an organic solvent mixed with EC and EMC in a volume ratio of 3:7 to achieve a concentration of 1 M.

[0101] A 4wt% PVA-CN solution was prepared by adding PVA-CN to the above electrolyte. In addition, a 0.4wt% DBA solution was prepared by adding 1,4-Phenylene diboronic Acid to the above electrolyte.

[0102] A composition for forming a gel polymer electrolyte was obtained by mixing 1 g of the above 4 wt% PVA-CN solution and 1 g of the above 0.4 wt% DBA solution.

[0103] The above composition for forming a gel polymer electrolyte was gelled at 25°C to prepare a gel polymer electrolyte (PVA-CN-DBA gel).

[0104] (2) Manufacturing of secondary batteries

[0105] LiNi as the positive active material 0.8 Co 0.1 Mn 0.1 O2 was used, and the above-mentioned positive active material: PVdF: Super P was mixed in a weight ratio of 94:3:3 to produce 2mAh / cm² 2 A positive electrode of the grade was manufactured.

[0106] Graphite (Gr) was used as the negative electrode active material, and a negative electrode was prepared by mixing the negative electrode active material: PVdF: Super-P in a weight ratio of 94:3:3.

[0107] A secondary battery was manufactured by placing the prepared liquid electrolyte between the cathode and the anode and then sealing it.

[0108] A secondary battery having a gel-type electrolyte was manufactured by performing a cross-linking reaction at 25°C on the secondary battery after the above initial cycle was completed.

[0109] Example 2

[0110] An electrolyte and a secondary battery were prepared in the same manner as in Example 1, except that a 0.2 wt% DBA solution was added to the above electrolyte instead of a 0.4 wt% DBA solution.

[0111] Example 3

[0112] An electrolyte and a secondary battery were prepared in the same manner as in Example 1, except that a 0.1 wt% DBA solution was added to the above electrolyte instead of a 0.4 wt% DBA solution.

[0113] Comparative Example 1

[0114] A secondary battery was manufactured in the same manner as in Example 1, except that DBA solution was not added to the above electrolyte, and 2wt% PVA-CN solution was added instead of 1g of 4wt% PVA-CN solution.

[0115] Comparative Example 2

[0116] A secondary battery was manufactured in the same manner as in Example 1, except that the PVA-CN solution and DBA solution were not added to the above electrolyte.

[0117] Experimental Example

[0118] 1. Fourier Transform Infrared Spectroscopy (FT-IR) analysis

[0119] The synthesis of the above gel polymer electrolyte was confirmed through FT-IR spectroscopy (Thermo, Nicolet 6700).

[0120] The gel polymer electrolyte prepared from Example 1 was crushed and washed three times with ethanol (Samjeon Chemical). The washed gel polymer electrolyte fragments were dried in a vacuum oven at 40°C for more than one day and then analyzed by FT-IR.

[0121] Figure 1 is Fourier Transform Infrared Spectroscopy (FT-IR) data of a gel polymer electrolyte (PVA-CN-DBA gel) prepared by gelling the DBA solution, PVA-CN solution, and composition for forming a gel polymer electrolyte of Example 1.

[0122] Referring to Fig. 1, the OH peak is at 3000 cm⁻¹ -1 up to 3500 cm -1 It is observed at the position, and the C≡N peak is at 2250 cm⁻¹ -1 It is observed at the location.

[0123] Before synthesis, the OH peak of DBA and PVA-CN and the C≡N peak of PVA-CN were both observed. However, after synthesis, the OH peak decreased and the C≡N peak was still observed.

[0124] Accordingly, it was confirmed that the OH groups of PVA-CN and DBA reacted and were removed, while the C≡N groups of PVA-CN were still present.

[0125] 2. Evaluation of Gelation Time

[0126] The time until gel polymer electrolytes prepared according to the examples and comparative examples gelled at room temperature (25 ℃) was measured.

[0127] 3. Flame Retardancy Evaluation

[0128] To evaluate the combustibility of the electrolyte, the self-extinguishing time of the electrolytes of Examples 1 to 3 and Comparative Examples 1 to 2 was measured. Considering that the combustion time varies depending on the weight of the electrolyte, the present invention introduced the combustion time per weight (unit: s / g).

[0129] The content of the polymer added to the electrolyte (or electrolyte solution) prepared according to the above-described examples and comparative examples, the results of the gelation time evaluation, and the results of the flame retardancy evaluation are shown in Table 1 below.

[0130] 4. Evaluation of Dose Retention Rate

[0131] The secondary batteries prepared according to the examples and comparative examples were charged (CC / CV, 0.5C, 4.3V, 0.05C CUT-OFF) and discharged (CC, 0.5C, 2.8V CUT-OFF) at room temperature (25 ℃) to measure the room temperature discharge capacity (CC: Constant Current, CV: Constant Voltage). The above charging and discharging were considered as one cycle and repeated 190 times.

[0132] Afterwards, the room temperature life characteristics were evaluated as a percentage of the discharge capacity at 190 cycles divided by the discharge capacity at 1 cycle.

[0133] The type of polymer added to the electrolyte (or electrolyte solution) prepared according to the above-described examples and comparative examples, the form of the electrolyte (gel or liquid phase), and the results of the capacity retention rate evaluation are shown in Table 1 below.

[0134] PVA-CN Concentration DBA Concentration Gelation Time Autoextinguishing Time (s / g) Volume Retention Rate (%) Example 1 2wt% 0.2wt% 3 days - 84.83 Example 2 2wt% 0.3wt% 3 days - 83.2 Example 3 2wt% 0.1wt% 4 days 1.68 4.84 Example 4 2wt% 0.5wt% 7 days - 78.74 Comparative Example 1 2wt% - 3 weeks or more 3.48 5.72 Comparative Example 2 - 54.28 8.44

[0135] In Table 1, compared to the comparative examples, the examples showed reduced gelation time at room temperature (25°C) and improved flame retardant properties.

[0136] Figure 2 is an image of the gel of Example 1 being directly ignited.

[0137] Figure 3 is an image of the gel of Example 1 after ignition for 4 seconds.

[0138] FIG. 4 is a graph showing the cycle-capacity retention rate performance of lithium secondary batteries of Examples 1 to 4 and Comparative Examples 1 to 2 at room temperature (25 ℃).

[0139] Even when Example 1 was ignited for 4 seconds, it did not ignite, so flame-retardant properties could be observed.

[0140] Referring to Table 1, the examples containing the gel polymer electrolyte showed a gelation time of less than one week at room temperature (25 ℃) and flame retardant properties compared to the comparative examples.

[0141] Comparative Example 1 did not use DBA solution and used 2wt% PVA-CN solution instead of 1g of 4wt% PVA-CN solution, but the crosslinking reaction was not sufficiently performed, so the gelation time increased and flame retardant properties could not be observed.

[0142] Comparative Example 2 used a liquid electrolyte in which PVA-CN solution and DBA solution were not added to the above electrolyte, and flame retardant properties could not be observed.

[0143] Accordingly, the gel polymer electrolyte is located between the negative and positive electrodes, and can be gelled through a cross-linking reaction in the secondary battery, and the lifespan characteristics can be improved due to the flame-retardant properties of the secondary battery. The description above is merely an example of applying the principles of the present disclosure, and other configurations may be further included without departing from the scope of the present invention.

Claims

1. Lithium salt; Organic solvent; Compounds represented by the following chemical formula 1; and Composition for forming a gel polymer electrolyte comprising polyvinyl alcohol substituted with nitrile groups: [Chemical Formula 1] (In the above Chemical Formula 1, R1, R2, R3, or R4 are independently a single bond or an alkylene group having 1 to 5 carbon atoms, and L is a single bond, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, or an aromatic hydrocarbon group having 6 to 20 carbon atoms).

2. A composition for forming a gel polymer electrolyte according to Claim 1, wherein the compound represented by Formula 1 comprises at least one of the compounds represented by Formulas 2 to 4 below. [Chemical Formula 2] [Chemical Formula 3] [Chemical Formula 4] 3. A composition for forming a gel polymer electrolyte according to claim 1, wherein the compound represented by Chemical Formula 1 is included in an amount of 0.01% to 1% by weight relative to the total weight of the composition.

4. A composition for forming a gel polymer electrolyte according to claim 1, wherein the polyvinyl alcohol substituted with a nitrile group comprises a repeating unit represented by the following chemical formula 5 and a repeating unit represented by the following chemical formula 6: [Chemical Formula 5] [Chemical Formula 6] (In the above chemical formula 6, R5 is an alkylene group having 1 to 5 carbon atoms).

5. A composition for forming a gel polymer electrolyte according to claim 4, wherein the molar ratio of the repeating unit represented by chemical formula 5 and the repeating unit represented by chemical formula 6 is 5:95 to 60:

40.

6. A composition for forming a gel polymer electrolyte according to claim 1, wherein the polyvinyl alcohol substituted with nitrile groups is included in an amount of 0.1% to 10% by weight relative to the total weight of the composition.

7. A composition for forming a gel polymer electrolyte according to claim 1, wherein the organic solvent comprises at least one selected from the group consisting of dimethyl carbonate (DMC), diethyl carbonate (DEC), dipropyl carbonate (DPC), methylpropyl carbonate (MPC), ethylpropyl carbonate (EPC), ethylmethyl carbonate (EMC), ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate (BC), or compounds containing these.

8. In Claim 1, the lithium salt is LiPF6, LiClO4, LiBF4, LiFSI, LiTFSI, LiSO3CF3, LiBOB, LiFOB, LiDFOB, LiDFBP, LiTFOP, LiPO2F2, LiCl, LiBr, LiI, LiB10Cl 10 A composition for forming a gel polymer electrolyte comprising at least one selected from the group consisting of LiCF3SO3, LiCF3CO2, LiAsF6, LiSbF6, LiAlCl4, CH3SO3Li, CF3SO3Li, LiSCN, LiC(CF3SO2)3, or compounds containing these.

9. The composition of Claim 1, wherein the composition is a composition for forming a gel polymer electrolyte that gels in the range of 20°C to 30°C.

10. A gel polymer electrolyte prepared by gelling the composition for forming a gel polymer electrolyte of Claim 1.

11. Anode; A cathode facing the anode; and A secondary battery comprising the gel polymer electrolyte of claim 10.

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