Title of Invention: Non-aqueous electrolyte for lithium secondary battery and lithium secondary battery comprising same technical field [One] Cross-Citation with Related Application(s) [2] This application claims the benefit of priority based on Korean Patent Application No. 10-2019-0147431 on November 18, 2019 and Korean Patent Application No. 10-2020-0151165 on November 12, 2020, All content disclosed in the literature is incorporated as a part of this specification. [3] [4] technical field [5] The present invention relates to a non-aqueous electrolyte for a lithium secondary battery and a lithium secondary battery comprising the same. background [6] In modern society, the dependence on electric energy is increasing, and accordingly, the production of electric energy is further increasing. In order to solve the environmental problems that occurred during this process, new and renewable energy generation is in the spotlight as a next-generation power generation system. In the case of such renewable energy, since it exhibits intermittent power generation characteristics, a large-capacity power storage device is essential in order to stably supply power. Among these power storage devices, a lithium ion battery is in the spotlight as a device with the highest energy density that has been commercialized. [7] The lithium ion battery includes a positive electrode made of a transition metal oxide containing lithium, a negative electrode capable of storing lithium, an electrolyte solution containing an organic solvent containing lithium salt, and a separator. [8] In the case of the anode, energy is stored through the redox reaction of the transition metal, which leads to the fact that the transition metal must be included in the cathode material. [9] On the other hand, as the positive electrode active material structurally collapses during repeated charging and discharging, the performance of the positive electrode is deteriorated. That is, when the structure of the positive electrode is collapsed, metal ions eluted from the surface of the positive electrode are electro-deposited on the negative electrode, thereby deteriorating the performance of the battery. This phenomenon tends to be accelerated when the potential of the positive electrode is increased or the battery is exposed to high temperature. [10] Therefore, in order to control the deterioration behavior of the battery, research has been conducted on the application of an additive that forms a film on the positive electrode, and with this, the study of inhibiting the electrodeposition of the eluted transition metal on the negative electrode or the occurrence of ion substitution, etc. is in progress. . DETAILED DESCRIPTION OF THE INVENTION technical challenge [11] An object of the present invention is to solve the above problems, and to provide a non-aqueous electrolyte for a lithium secondary battery comprising an additive that forms a complex with a transition metal ion eluted from a positive electrode. [12] In addition, an object of the present invention is to provide a lithium secondary battery having improved high-rate charge-discharge characteristics by including the non-aqueous electrolyte for a lithium secondary battery. means of solving the problem [13] In one embodiment of the present invention for achieving the above object, [14] Provided is a non-aqueous electrolyte for a lithium secondary battery comprising a compound represented by the following formula (1) as a lithium salt, an organic solvent, and an additive. [15] [Formula 1] [16] [17] In Formula 1, [18] R 1 to R 6 are each independently hydrogen, an alkyl group having 1 to 5 carbon atoms, or a -CN group, and at least one of R 1 to R 6 is a -CN group. [19] [20] On the other hand, in another embodiment of the present invention [21] A lithium secondary battery comprising a negative electrode, a positive electrode, a separator interposed between the negative electrode and the positive electrode, and a non-aqueous electrolyte, wherein the non-aqueous electrolyte includes the non-aqueous electrolyte for a lithium secondary battery of the present invention. Effects of the Invention [22] The compound represented by Formula 1 contained in the non-aqueous electrolyte of the present invention is a compound containing a cyano group in its structure, and the cyano group forms a complex with a transition metal ion eluted from the positive electrode of the lithium secondary battery, so that the metal ion is the negative electrode electrodeposition can be suppressed. Since the non-aqueous electrolyte containing these additives is oxidatively decomposed before the organic solvent to form a film on the surface of the anode, it is possible to suppress the continuous decomposition reaction between the anode and the organic solvent. Therefore, when such a non-aqueous electrolyte is included, a lithium secondary battery having improved high-rate charge-discharge characteristics can be implemented. Brief description of the drawing [23] The following drawings attached to the present specification illustrate preferred embodiments of the present invention, and serve to further understand the technical spirit of the present invention together with the above-described content of the present invention, so the present invention is limited to the matters described in those drawings It should not be construed as being limited. [24] 1 is a graph showing an electrochemical stability evaluation result of a non-aqueous electrolyte according to Experimental Example 1. FIG. [25] 2 is a graph showing the results of measurement of the decomposition start voltage of the non-aqueous electrolyte of Example 3 and Comparative Example 2 according to Experimental Example 2; [26] 3 is a graph showing differential capacity curves of lithium secondary batteries of Example 5 and Comparative Example 3 according to Experimental Example 3; [27] 4 is a graph showing the impedance evaluation results of the lithium secondary batteries of Example 5 and Comparative Example 3 according to Experimental Example 5; [28] 5 is a graph showing evaluation results of high-temperature cycle characteristics of secondary batteries of Example 5 and Comparative Example 3 according to Experimental Example 6; Best mode for carrying out the invention [29] Hereinafter, the present invention will be described in more detail. [30] The terms or words used in the present specification and claims should not be construed as being limited to their ordinary or dictionary meanings, and the inventor may properly define the concept of the term in order to best describe his invention. Based on the principle that there is, it should be interpreted as meaning and concept consistent with the technical idea of ​​the present invention. [31] [32] The positive electrode is composed of an acid formed by hydrolysis/thermal decomposition of lithium salt or an acid generated by a side reaction between the conventional positive electrode and the electrolyte, such as hydrogen fluoride (HF), or structural change of the positive electrode due to repeated charging and discharging. The transition metal is easily eluted into the electrolyte, and the eluted transition metal ions are re-deposited on the anode, causing an increase in the resistance of the anode. Alternatively, the transition metal transferred to the negative electrode through the electrolyte is electrodeposited on the negative electrode, causing self-discharge of the negative electrode, and destroying the solid electrolyte interphase (SEI) film that gives the negative electrode passivation ability. increase the interfacial resistance. [33] Since these series of reactions reduce the amount of available lithium ions in the battery, not only the capacity of the battery is deteriorated, but also the resistance of the electrolyte is increased because it is accompanied by a decomposition reaction of the electrolyte. In addition, when metal impurities are included in the electrode when the electrode of the anode is configured, the metal ions eluted on the surface of the cathode are electrodeposited by dissolving the foreign material in the anode during initial charging. These electrodeposited metal ions grow into dendrites and cause an internal short circuit of the battery, which is a major cause of low voltage failure. [34] In the present invention, it forms a complex with the eluted metal ions that cause such deterioration and poor behavior, and includes an additive capable of preventing the metal ions from being electrodeposited on the negative electrode. An object of the present invention is to provide a non-aqueous electrolyte for a lithium secondary battery capable of forming a film and a lithium secondary battery with improved high-rate charge/discharge at high temperature by including the same. [35] [36] Non-aqueous electrolyte for lithium secondary battery [37] Specifically, in an embodiment of the present invention [38] Provided is a non-aqueous electrolyte for a lithium secondary battery comprising a compound represented by the following formula (1) as a lithium salt, an organic solvent, and an additive. [39] [Formula 1] [40] [41] In Formula 1, [42] R 1 to R 6 are each independently hydrogen, an alkyl group having 1 to 5 carbon atoms, or a -CN group, and at least one of R 1 to R 6 is a -CN group. [43] [44] lithium salt [45] First, in the non-aqueous electrolyte for a lithium secondary battery of the present invention, the lithium salt may be used without limitation, those commonly used in the electrolyte for a lithium secondary battery, for example, Li + as a cation, F - as an anion , Cl - , Br - , I - , NO 3 - , N(CN) 2 - , BF 4 - , ClO 4 - , B 10 Cl 10 - , AlCl 4 - , AlO 4 - , PF 6 - , CF 3 SO 3 - , CH 3 CO 2 - , CF 3 CO 2 - , AsF 6 - , SbF 6 - , CH 3 SO 3 - , (CF 3 CF 2 SO 2 ) 2 N - , (CF 3 SO 2 ) 2 N - , (FSO 2 ) 2 N - , BF 2 C 2 O 4 - , BC 4 O 8 - , PF 4 C 2 O 4 - , PF 2 C 4 O 8 - , (CF 3 ) 2 PF 4 - , (CF 3 ) 3 PF 3 - , (CF 3 ) 4 PF 2 - , (CF 3 ) 5 PF - , (CF 3) 6 P - , C 4 F 9 SO 3 - , CF 3 CF 2 SO 3 - , CF 3 CF 2 (CF 3 ) 2 CO - , (CF 3 SO 2 ) 2 CH - , CF 3 (CF 2 ) 7 SO 3 - and SCN -At least one selected from the group consisting of may be mentioned. [46] Specifically, the lithium salt is LiCl, LiBr, LiI, LiBF 4 , LiClO 4 , LiB 10 Cl 10 , LiAlCl 4 , LiAlO 4 , LiPF 6 , LiCF 3 SO 3 , LiCH 3 CO 2 , LiCF 3 CO 2 , LiAsF 6 , LiSbF 6 , LiCH 3 SO 3 , LiFSI (Lithium bis(fluorosulfonyl)imide, LiN(SO 2 F) 2), LiBETI (lithium bis(perfluoroethanesulfonyl) imide, LiN(SO 2 CF 2 CF 3 ) 2 and LiTFSI (lithium bis(trifluoromethanesulfonyl) imide, LiN(SO 2 CF 3 ) 2 ) A single substance or two or more kinds selected from the group consisting of In addition to these, lithium salts commonly used in electrolytes for lithium secondary batteries may be used without limitation. [47] The lithium salt can be appropriately changed within the range that can be used in general, but to be included in the electrolyte at a concentration of 0.8 M to 4.0 M, specifically, at a concentration of 1.0 M to 3.0 M, in order to obtain an optimal effect of forming a film for preventing corrosion of the electrode surface. can If the concentration of the lithium salt is less than 0.8 M, the effect of improving the low-temperature output of the lithium secondary battery and improving the cycle characteristics during high-temperature storage is insignificant. can [48] [49] (2) organic solvents [50] In the non-aqueous electrolyte for a lithium secondary battery according to the present specification, the organic solvent may include a cyclic carbonate-based organic solvent, a linear carbonate-based organic solvent, or a mixed organic solvent thereof. [51] The cyclic carbonate-based organic solvent is a high-viscosity organic solvent, which has a high dielectric constant and can well dissociate lithium salts in the electrolyte, and specific examples thereof include ethylene carbonate (EC), propylene carbonate (PC), 1,2-butylene. At least one organic solvent selected from the group consisting of carbonate, 2,3-butylene carbonate, 1,2-pentylene carbonate, 2,3-pentylene carbonate and vinylene carbonate, among them, ethylene carbonate may include [52] In addition, the linear carbonate-based organic solvent is an organic solvent having a low viscosity and a low dielectric constant, and representative examples thereof include dimethyl carbonate (DMC), diethyl carbonate (DEC), dipropyl carbonate, ethylmethyl carbonate ( EMC), at least one organic solvent selected from the group consisting of methyl propyl carbonate and ethyl propyl carbonate may be used, and specifically, ethyl methyl carbonate (EMC) may be included. [53] The organic solvent is preferably a mixed organic solvent of a cyclic carbonate-based organic solvent and a linear carbonate-based organic solvent in order to prepare an electrolyte having high ionic conductivity. [54] In addition, the organic solvent may further include a linear ester-based organic solvent and/or a cyclic ester-based organic solvent to the cyclic carbonate-based organic solvent and/or the linear carbonate-based organic solvent. [55] Specific examples of the linear ester-based organic solvent include at least one organic solvent selected from the group consisting of methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate and butyl propionate. can be heard [56] In addition, the cyclic ester-based organic solvent includes at least one organic solvent selected from the group consisting of γ-butyrolactone, γ-valerolactone, γ-caprolactone, σ-valerolactone and ε-caprolactone. can [57] Meanwhile, as the organic solvent, an organic solvent commonly used in an electrolyte for a lithium secondary battery may be added without limitation, if necessary. For example, at least one organic solvent of an ether-based organic solvent, an amide-based organic solvent, and a nitrile-based organic solvent may be further included. [58] [59] (3) additives [60] The non-aqueous electrolyte for a lithium secondary battery of the present invention may include a compound represented by the following Chemical Formula 1 as an additive. [61] [Formula 1] [62] [63] In Formula 1, [64] R 1 to R 6 are each independently hydrogen, an alkyl group having 1 to 5 carbon atoms, or a -CN group, and at least one of R 1 to R 6 is a -CN group. [65] [66] Specifically, in Formula 1, in Formula 1, R 1 to R 6 are each independently hydrogen, an alkyl group having 1 to 4 carbon atoms, or a -CN group, and at least one of R 1 to R 6 may be a -CN group. there is. [67] Or in Formula 1, R 1 is an alkyl group having 1 to 3 carbon atoms or a —CN group, R 2 is hydrogen or an alkyl group having 1 to 3 carbon atoms, and R 3 to R 6 are each independently hydrogen and 1 to 4 carbon atoms. An alkyl group or a -CN group, and at least one of R 1 and R 3 to R 6 may be a -CN group. [68] Alternatively, in Formula 1, R 1 is a -CN group, R 2 is hydrogen or an alkyl group having 1 to 3 carbon atoms, and R 3 to R 6 may be each independently hydrogen, an alkyl group having 1 to 3 carbon atoms, or a -CN group. . [69] Or in Formula 1, R 1 is a -CN group, R 2 is hydrogen, R 3 and R 6 are each independently hydrogen or a -CN group, R 4 and R 5 are each independently hydrogen, carbon number of 1 to It may be an alkyl group of 3 or a -CN group. [70] Alternatively, in Formula 1, R 1 is a -CN group, R 2 is hydrogen, R 3 and R 6 are each independently hydrogen, and R 4 and R 5 may be each independently hydrogen or a -CN group. [71] Preferably, the compound represented by Formula 1 may be a compound represented by Formula 1a below, for example, coumarin-3-carbonitrile. [72] [Formula 1a] [73] [74] [75] In the present invention, the compound represented by Formula 1 included as an electrolyte additive is a compound including a cyano group included in the structure, and the cyano group forms a complex with a transition metal ion eluted from the positive electrode of a lithium secondary battery to form a metal ion Electrodeposition on this cathode can be suppressed. Moreover, these additives are oxidatively decomposed before the organic solvent to form a strong film on the surface of the anode, and this film can suppress the continuous decomposition reaction between the anode and the organic solvent. Therefore, by providing the non-aqueous electrolyte containing the additive, it is possible to implement a lithium secondary battery with improved high-rate charge and discharge. [76] [77] Meanwhile, the compound of Formula 1 may be included in an amount of 0.05 wt% or more and less than 1.2 wt%, specifically 0.1 wt% to 1 wt%, based on the total weight of the non-aqueous electrolyte. [78] When the compound represented by Formula 1 is included in the above range, it is possible to manufacture a secondary battery with improved overall performance. For example, when the compound represented by Formula 1 is included in an amount of 0.05 wt% or more and less than 1.2 wt%, removal of forming a complex with metal ions while maximally suppressing disadvantages such as side reactions due to additives, lowering initial capacity, and increasing resistance At the same time, a strong film can be formed on the surface of the anode. If the content of the compound represented by the formula (1) is included in 1.2 wt% or more, the solubility of the additive in the non-aqueous organic solvent is lowered, so that a side reaction by the additive is generated, or an initial capacity decrease due to an increase in resistance may be caused. there is. [79] [80] lithium secondary battery [81] In another embodiment of the present invention, there is provided a lithium secondary battery comprising the non-aqueous electrolyte for a lithium secondary battery of the present invention. [82] On the other hand, the lithium secondary battery of the present invention can be manufactured by forming an electrode assembly in which a positive electrode, a negative electrode, and a separator are sequentially stacked between the positive and negative electrodes, stored in a battery case, and then adding the non-aqueous electrolyte of the present invention. [83] The method for manufacturing the lithium secondary battery of the present invention may be manufactured and applied according to a conventional method known in the art, and will be described in detail below. [84] [85] (1) Anode [86] The positive electrode may be prepared by coating a positive electrode slurry including a positive electrode active material, a binder, a conductive material and a solvent on a positive electrode current collector, followed by drying and rolling. [87] The positive electrode current collector is not particularly limited as long as it has conductivity without causing a chemical change in the battery. For example, stainless steel, aluminum, nickel, titanium, calcined carbon, or carbon on the surface of aluminum or stainless steel. , nickel, titanium, silver, etc. may be used. [88] The positive active material is a compound capable of reversible intercalation and deintercalation of lithium, and is specifically made of nickel (Ni), cobalt (Co), manganese (Mn), iron (Fe) and aluminum (Al). It may include a lithium composite metal oxide including at least one metal selected from the group and lithium. [89] More specifically, the lithium composite metal oxide is a lithium-manganese oxide (eg, LiMnO 2 , LiMn 2 O 4 , etc.), a lithium-cobalt-based oxide (eg, LiCoO 2 , etc.), lithium-nickel-based oxide (eg, LiNiO 2 , etc.), lithium-nickel-manganese oxide (eg, LiNi 1-Y Mn Y O 2 (0