technology field [One] The present invention relates to a positive electrode for a lithium secondary battery and a lithium secondary battery, and more specifically, to a positive electrode for a lithium secondary battery and a lithium secondary battery with improved safety without deterioration in battery life characteristics. This application claims the benefit of priority based on Korean Patent Application No. 10-2021-0043090 dated April 2, 2021, and all contents disclosed in the literature of the Korean patent application are included as part of this specification. [2] background art [3] As technology development and demand for mobile devices increase, demand for secondary batteries as an energy source is rapidly increasing. Among these secondary batteries, lithium secondary batteries having high energy density and operating potential, long cycle life, and low self-discharge rate have been commercialized and widely used. [4] Recently, as lithium secondary batteries are used as a power source for medium-large devices such as electric vehicles, high capacity, high energy density, and low cost of lithium secondary batteries are further required. Accordingly, inexpensive Ni, Mn, Studies for the use of Fe are being actively conducted. [5] One of the main research tasks of such a lithium secondary battery is to improve the safety of a battery using the same while realizing an electrode active material of high capacity and high output. Lithium transition metal composite oxides are used as cathode active materials for lithium secondary batteries, and among them, lithium cobalt composite metal oxides such as LiCoO 2 having high operating voltage and excellent capacity characteristics are mainly used. However, LiCoO 2 has very poor thermal characteristics due to destabilization of the crystal structure due to delithiation, and when an internal short circuit occurs due to pressure from the outside in a charged state, the cathode active material itself is decomposed, which may cause the battery to rupture and ignite. . In addition, when an overcurrent flows momentarily, there is a problem in that safety problems such as ignition or explosion occur due to this. [6] Accordingly, Korean Patent Publication No. 2019-0047203 discloses a technology for securing the safety of a battery by interposing an overcharge prevention layer between a cathode current collector and a cathode active material layer to increase resistance during overcharging to block charging current. However, although the safety of the electrode having the overcharge prevention layer is improved as described above, since the adhesive strength is low due to the difference in composition between the overcharge prevention layer and the positive electrode active material layer, interlayer cracks may occur, thereby reducing the lifespan of the battery. . In addition, the electrode has a limitation that may cause a problem in terms of safety when penetrated by an acicular body due to low penetration resistance. [7] Therefore, when a metal object such as a nail penetrates the electrode from the outside, not only is safety high so that heat or ignition due to overcurrent does not occur, but also cracks occurring between each layer of the anode prevent degradation of the lifespan characteristics of the battery. There is a need to develop technologies that can be improved. [8] DETAILED DESCRIPTION OF THE INVENTION technical challenge [9] Therefore, an object of the present invention is to improve safety so that heat or ignition due to overcurrent does not occur when a metal object such as a nail penetrates the electrode from the outside, and lifespan reduced due to cracks between each layer constituting the anode It is to provide a positive electrode for a secondary battery with improved characteristics and a lithium secondary battery including the same. [10] means of solving the problem [11] In order to solve the above problems, [12] In one embodiment, the present invention [13] current collector; [14] a first coating layer formed on one side or both sides of the current collector and containing a first cathode active material; [15] a pattern layer formed on the first coating layer and having a form in which a conductive material is dispersed in a binder; and [16] A second coating layer formed on the first coating layer on which the pattern layer is formed and containing a second cathode active material, [17] The area of ​​the region where the pattern layer is formed is 30% to 80% of the total area of ​​the first coating layer, providing a cathode for a lithium secondary battery. [18] At this time, the pattern layer may have a dot, mesh, stripe, or dendritic surface structure. [19] In addition, the first coating layer and the second coating layer each include 1 to 10 parts by weight of a binder based on 100 parts by weight of the total, and the binder is each polyvinylidene fluoride-hexafluoropropylene copolymer (PVDF-co-HFP ), polyvinylidenefluoride, polyacrylonitrile, polymethylmethacrylate, and copolymers thereof. [20] In addition, the binder of the pattern layer is polyvinylidene fluoride-hexafluoropropylene copolymer (PVDF-co-HFP), polyvinylidenefluoride, polyacrylonitrile, polymethyl methacrylate (polymethylmethacrylate), polyvinyl alcohol, carboxymethylcellulose (CMC), starch, hydroxypropylcellulose, regenerated cellulose, polyvinylpyrrolidone, tetrafluoroethylene, polyethylene, polypropylene, polyacrylic acid, ethylene-propylene-diene monomer (EPDM), sulfonated EPDM, styrene butadiene rubber (SBR), fluororubber, polyacrylic acid (polyacrylic acid), and copolymers thereof. [21] In addition, the conductive material of the pattern layer is graphite including natural graphite or artificial graphite; carbon black including acetylene black, Ketjen black, channel black, farnes black, lamp black, or thermal black; conductive fibers including carbon fibers or metal fibers; carbon nanotubes; metal powders containing fluorocarbons, aluminum or nickel; zinc oxide; potassium titanate; titanium oxide; And it may include at least one selected from the group consisting of polyphenylene derivatives. [22] In addition, the conductive material of the pattern layer may be included in an amount of 1 to 50 parts by weight based on 100 parts by weight of the binder. [23] In addition, the average height of the pattern layer may be 0.5 μm to 50 μm based on the cross section, and the average thickness of the first coating layer may be 0.1 μm to 10 μm. [24] In addition, the second coating layer may satisfy Equation 1 below: [25] [Equation 1] [26] 6≤SD/PD≤100 [27] In the above formula 1, [28] SD represents the average thickness of the second coating layer, [29] PD represents the average thickness of the patterned layer. [30] In addition, the first cathode active material may include a lithium iron phosphate compound represented by Formula 1 below: [31] [Formula 1] [32] Li 1+a Fe 1-b M 1 b (PO 4-c )X c [33] In Formula 1, [34] M 1 is at least one selected from Al, Mg, and Ti; [35] X is at least one selected from F, S and N, [36] a, b and c are respectively -0.5≤x≤+0.5, 0≤y≤0.5 and 0≤z≤0.1. [37] Furthermore, the second cathode active material may include a lithium metal composite oxide represented by Formula 2 below: [38] [Formula 2] [39] LiCo 1-q M 2 q O 2 [40] In Formula 2, [41] M 2 is W, Cu, Fe, V, Cr, Ti, Zr, Zn, Al, In, Ta, Y, La, Sr, Ga, Sc, Gd, Sm, Ca, Ce, Nb, Mg, B, and At least one element selected from the group consisting of Mo, [42] q is 0≤q≤0.4. [43] [44] In addition, the present invention, in one embodiment, provides a lithium secondary battery having the positive electrode according to the present invention. [45] Effects of the Invention [46] A positive electrode for a lithium secondary battery according to the present invention includes a first coating layer and a second coating layer sequentially on a current collector, and a pattern layer in which a conductive material is dispersed in a binder is formed between the first coating layer and the second coating layer at a specific area ratio. By introducing it, the safety of the battery is improved, so when a metal material penetrates the electrode from the outside, not only can heat or ignition due to overcurrent not occur, but also the adhesion between each layer constituting the positive electrode is improved, thereby improving the lifespan of the battery. can improve [47] Brief description of the drawing [48] 1 is a cross-sectional view showing the structure of a positive electrode for a lithium secondary battery according to the present invention. [49] BEST MODE FOR CARRYING OUT THE INVENTION [50] Since the present invention can have various changes and various embodiments, specific embodiments will be described in detail in the detailed description. [51] However, this is not intended to limit the present invention to specific embodiments, and should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention. [52] In the present invention, the term "comprises" or "has" is intended to designate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, but one or more other features It should be understood that it does not preclude the possibility of the presence or addition of numbers, steps, operations, components, parts, or combinations thereof. [53] Further, in the present invention, when a part such as a layer, film, region, plate, etc. is described as being “on” another part, this includes not only the case where it is “directly on” the other part, but also the case where another part is present in the middle thereof. . Conversely, when a part such as a layer, film, region, plate, etc. is described as being “under” another part, this includes not only the case where it is “directly under” the other part, but also the case where there is another part in between. In addition, in the present application, being disposed "on" may include the case of being disposed not only on the upper part but also on the lower part. [54] [55] Hereinafter, the present invention will be described in more detail. [56] [57] Cathode for lithium secondary battery [58] In one embodiment, the present invention [59] current collector; [60] a first coating layer formed on one side or both sides of the current collector and containing a first cathode active material; [61] a pattern layer formed on the first coating layer and having a form in which a conductive material is dispersed in a binder; and [62] A second coating layer formed on the first coating layer on which the pattern layer is formed and containing a second cathode active material, [63] The area of ​​the region where the pattern layer is formed is 30% to 80% of the total area of ​​the first coating layer, providing a cathode for a lithium secondary battery. [64] [65] 1 is a cross-sectional view showing the structure of a cathode 100 for a lithium secondary battery according to the present invention. As shown in FIG. 1, the cathode 100 for a lithium secondary battery according to the present invention includes a current collector 110, a first coating layer 120 and the second coating layer 140 are sequentially stacked, and the pattern layer 130 is introduced between the first coating layer 120 and the second coating layer 140. [66] At this time, the pattern layer 130 is interposed between the first coating layer 120 and the second coating layer 140 to improve the adhesion between the first coating layer 120 and the second coating layer 140, while the anode ( 100) may serve to increase the electrical conductivity. [67] To this end, the pattern layer 130 has a form in which a conductive material is dispersed in a binder. At this time, the binder may further include additives such as a dispersant and a surfactant in addition to the conductive material, but does not include a cathode active material exhibiting electrical activity. don't [68] A binder that may be included in the pattern layer 130 may be the same as or different from the binders included in the first coating layer 120 and the second coating layer 140 . For example, as a binder that may be included in the pattern layer 130, polyvinylidene fluoride-hexafluoropropylene copolymer (PVDF-co-HFP), polyvinylidenefluoride, polyacrylonitrile ( polyacrylonitrile), polymethylmethacrylate, polyvinyl alcohol, carboxymethylcellulose (CMC), starch, hydroxypropylcellulose, regenerated cellulose, polyvinylpyrrolidone, tetrafluoroethylene, polyethylene, polypropylene, poly Contains at least one resin selected from the group consisting of acrylic acid, ethylene-propylene-diene monomer (EPDM), sulfonated EPDM, styrene butadiene rubber (SBR), fluororubber, polyacrylic acid, and copolymers thereof can do. As one example, the binder may include a polyvinylidene fluoride-hexafluoropropylene copolymer. [69] In addition, as a conductive material that may be included in the pattern layer 130, graphite including natural graphite or artificial graphite; carbon black including acetylene black, Ketjen black, channel black, farnes black, lamp black, or thermal black; conductive fibers including carbon fibers or metal fibers; carbon nanotubes; metal powders containing fluorocarbons, aluminum or nickel; zinc oxide; potassium titanate; titanium oxide; And it may include at least one selected from the group consisting of polyphenylene derivatives. As an example, the conductive material may include at least one of acetylene black, ketjen black, channel black, farnes black, lamp black, or carbon black including thermal black. [70] In addition, the conductive material may be included in 1 to 50 parts by weight based on 100 parts by weight of the binder, specifically 5 to 40 parts by weight based on 100 parts by weight of the binder; 10 to 20 parts by weight; 20 to 40 parts by weight; 30 to 50 parts by weight; 15 to 35 parts by weight; or 15 to 25 parts by weight. [71] In the present invention, by controlling the content of the conductive material included in the pattern layer 130 within the above range, the adhesive strength between the first coating layer 120 and the second coating layer 140 is not effectively improved due to the low content of the binder, or It is possible to prevent that the electrical conductivity of the positive electrode 100 is not effectively increased due to the low content of the ash. [72] In addition, the pattern layer 130 may be applied without particular limitation as long as it maximizes the surface area without covering the entire surface of the first coating layer 120 . Specifically, the pattern layer 130 may have a dot, mesh, stripe, or dendritic surface structure. As an example, the pattern layer 130 may have a dendritic surface structure. [73] In addition, the binder of the pattern layer 130 may have a form of partially or fully infiltrating the gap between the first cathode active materials constituting the first coating layer 120, and at the same time constituting the second coating layer 140. It may have a form in which part or all of the gaps between the second cathode active materials are penetrated. [74] In addition, the pattern layer 130 may occupy 30% to 80% of the total area of ​​the first coating layer 120, specifically 30% to 70% of the total area of ​​the first coating layer 120; 30% to 60%; 30% to 50%; 40% to 70%; or 30% to 45%. In the present invention, by controlling the area of ​​the pattern layer 130 formed on the first coating layer 120 within the above range, the adhesion between the first coating layer 120 and the second coating layer 140 is increased while simultaneously moving lithium ions. It is possible to prevent deterioration of battery performance due to a decrease in temperature. [75] In addition, the average height of the pattern layer 130 may be 0.5 μm to 50 μm on a cross-sectional basis, specifically 0.5 μm to 40 μm; 0.5 μm to 20 μm; 0.5 μm to 10 μm; 1 μm to 40 μm; 5 μm to 30 μm; 5 μm to 20 μm; 15 μm to 25 μm; 5 μm to 15 μm; 10 μm to 20 μm; 3 μm to 17 μm; Or it may be 1 μm to 10 μm. The pattern layer 130 according to the present invention may have a semicircular cross-sectional structure when the shape is dot-shaped, and may have a cross-sectional structure close to a triangular pyramid when the shape is dendritic. The term "average height" may mean 1/2 of the highest height based on the cross-sectional structure of the pattern layer 130 . In the present invention, the specific surface area of ​​the pattern layer 130 can be maximized by adjusting the average height of the pattern layer 130 as described above, and through this, the adhesion between the first coating layer 120 and the second coating layer 140 is improved. can make it [76] [77] Meanwhile, the first coating layer 120 is formed on one side or both sides of the current collector 110 and includes a first cathode active material, a first conductive material, and a first binder. In this case, the first cathode active material may include a lithium iron phosphate compound represented by Formula 1 below: [78] [Formula 1] [79] Li 1+a Fe 1-b M 1 b (PO 4-c )X c [80] In Formula 1, [81] M 1 is at least one selected from Al, Mg, and Ti; [82] X is at least one selected from F, S and N, [83] a, b and c are respectively -0.5≤x≤+0.5, 0≤y≤0.5 and 0≤z≤0.1. [84] Specifically, the first cathode active material is a lithium iron phosphate compound represented by Chemical Formula 1 and is a group consisting of LiFePO 4 , Li(Fe,Al)PO 4 , Li(Fe,Mg)PO 4 and Li(Fe,Ti)PO 4 It may include one or more compounds selected from, and more specifically, LiFePO 4 may be used. [85] The lithium iron phosphate compound represented by Chemical Formula 1 may have an olivine structure. Lithium iron phosphate having an olivine structure shrinks in volume as lithium inside it escapes at an overcharge voltage of about 4.5V or higher. Accordingly, the conductive path of the first mixture layer 121 is quickly blocked to The mixture layer 121 acts as an insulating layer, and through this, the resistance of the first mixture layer 121 increases and the charging current is blocked to reach the overcharge end voltage. [86] In addition, the first coating layer 120 may include at least one selected from the group consisting of natural graphite, artificial graphite, carbon black, acetylene black, ketjen black, and carbon fiber as a first conductive material. For example, the first conductive material may include acetylene black. [87] In addition, the first binder is polyvinylidene fluoride-hexafluoropropylene copolymer (PVDF-co-HFP), polyvinylidenefluoride, polyacrylonitrile, polymethyl methacrylate ( polymethylmethacrylate) and at least one resin selected from the group consisting of copolymers thereof. As one example, the first binder may include polyvinylidenefluoride. [88] In addition, the first coating layer 120 may include 80 to 98 parts by weight of the first positive electrode active material, 1 to 10 parts by weight of the first conductive material, and 1 to 10 parts by weight of the first binder, based on 100 parts by weight of the total. As an example, the first coating layer 120 may include 84 to 96 parts by weight of the first cathode active material, 2 to 8 parts by weight of the first conductive material, and 2 to 8 parts by weight of the first binder, based on 100 parts by weight of the total. As another example, 88 to 96 parts by weight of the first cathode active material, 2 to 6 parts by weight of the first conductive material, and 2 to 6 parts by weight of the first binder may be included with respect to the total of 100 parts by weight. [89] In addition, the average thickness of the first coating layer 120 may be 0.1 μm to 10 μm, specifically 2 μm to 10 μm; 4 μm to 10 μm; Or it may be 5 μm to 9 μm. [90] [91] Furthermore, the second coating layer 140 is formed on the first coating layer 120 on which the pattern layer 130 is formed, and includes a second cathode active material, a second conductive material, and a second binder. In this case, the second cathode active material may include a lithium metal composite oxide represented by Formula 2 below: [92] [Formula 2] [93] LiCo 1-q M 2 q O 2 [94] In Formula 2, [95] M 2 is W, Cu, Fe, V, Cr, Ti, Zr, Zn, Al, In, Ta, Y, La, Sr, Ga, Sc, Gd, Sm, Ca, Ce, Nb, Mg, B, and At least one element selected from the group consisting of Mo, [96] q is 0≤q≤0.4. [97] The second cathode active material may be applied without particular limitation as long as it is a lithium metal composite oxide represented by Formula 2, but specifically, the second cathode active material includes LiCoO 2 , LiCo 0.5 Zn 0.5 O 2 , LiCo 0.7 Zn 0.3 O 2 , LiNi 0.5 Co 0.5 O 2 , LiCo 0.6 Fe 0.4 O 2 , LiCo 0.9 Fe 0.1 O 2 , LiCo 0.8 Al 0.2 O 2, LiCo 0.8 Mn 0.2 O 2 , LiCo 0.9 Mn 0.1 O 2 , and LiCo 0.8 Mn 0.1 Al 0.1 O 2 . [98] As an example, the cathode active material may be used alone or in combination with LiCoO 2 or LiCo 0.7 Zn 0.3 O 2 as lithium nickel cobalt oxide represented by Chemical Formula 1 . [99] In addition, the second coating layer 140 may include at least one selected from the group consisting of natural graphite, artificial graphite, carbon black, acetylene black, ketjen black, and carbon fiber as a second conductive material. For example, the first conductive material may include acetylene black. [100] In addition, the second binder is polyvinylidene fluoride-hexafluoropropylene copolymer (PVDF-co-HFP), polyvinylidene fluoride, polyacrylonitrile, polymethyl methacrylate ( polymethylmethacrylate) and at least one resin selected from the group consisting of copolymers thereof. As one example, the second binder may include polyvinylidenefluoride. [101] In addition, the second coating layer 140 may include 80 to 98 parts by weight of the second cathode active material, 1 to 10 parts by weight of the second conductive material, and 1 to 10 parts by weight of the second binder, based on 100 parts by weight of the total. As an example, the second coating layer 140 may include 84 to 96 parts by weight of the second cathode active material, 2 to 8 parts by weight of the second conductive material, and 2 to 8 parts by weight of the second binder, based on 100 parts by weight of the total. As another example, 88 to 96 parts by weight of the second positive electrode active material, 2 to 6 parts by weight of the second conductive material, and 2 to 6 parts by weight of the second binder may be included with respect to the total of 100 parts by weight. [102] Furthermore, the average thickness of the second coating layer 140 is not particularly limited, but may be specifically 50 μm to 300 μm, more specifically 100 μm to 200 μm; 80 μm to 150 μm; 120 μm to 170 μm; 150 μm to 300 μm; 200 μm to 300 μm; Or it may be 150 μm to 190 μm. [103] In addition, the second coating layer 140 may satisfy Equation 1 below: [104] [Equation 1] [105] 6≤SD/PD≤100 [106] In Equation 1, SD represents the average thickness of the second coating layer 140, and PD represents the average thickness of the pattern layer 130. [107] [108] Equation 1 represents the ratio (SD/PD) of the average thickness (SD) of the second coating layer 140 and the average thickness (PS) of the pattern layer 130, and the present invention sets Equation 1 to 6 to 100. may be satisfied, specifically 6 to 80; 10 to 60; 10 to 40; 10 to 30; 10 to 20; 20 to 70; 30 to 60; 15 to 35; 11 to 13; Alternatively, 10 to 15 may be satisfied. The present invention improves the adhesive strength between the first coating layer 120 and the second coating layer 140 by adjusting the average thickness ratio of the second coating layer 140 and the pattern layer 130 within the above range, resulting in cracks between the layers. can improve things [109] Meanwhile, as the current collector 110 for the positive electrode 100 for a lithium secondary battery according to the present invention, one having high conductivity without causing chemical change in the battery may be used. For example, stainless steel, aluminum, nickel, titanium, calcined carbon, etc. may be used, and aluminum or stainless steel may be surface-treated with carbon, nickel, titanium, silver, or the like. In addition, the current collector 110 may have fine irregularities formed on the surface to increase the adhesion of the cathode active material, and various forms such as film, sheet, foil, net, porous material, foam, and nonwoven fabric are possible. In addition, the average thickness of the current collector 110 may be appropriately applied in the range of 3 to 500 μm in consideration of the conductivity and total thickness of the positive electrode 100 to be manufactured. [110] [111] As described above, the positive electrode 100 for a lithium secondary battery according to the present invention includes the first coating layer 120 and the second coating layer 140 sequentially on the current collector 110, but the first coating layer 120 and By introducing the pattern layer 130 in the form of a conductive material dispersed in a binder between the second coating layer 140 at a specific area ratio, the safety of the battery is improved, so when a metal material penetrates the electrode from the outside, heat or ignition due to overcurrent occurs etc. may not occur, and since the adhesion between each layer constituting the positive electrode 100 is improved, the lifespan characteristics of the battery may be improved. [112] [113] lithium secondary battery [114] In addition, in one embodiment of the present invention, [115] anode according to the present invention described above; cathode; And it provides a lithium secondary battery comprising a separator positioned between the positive electrode and the negative electrode. [116] The lithium secondary battery according to the present invention may have a structure including the positive electrode and the negative electrode of the present invention described above, and the positive electrode and the negative electrode are impregnated with a lithium salt-containing electrolyte. [117] Here, the anode is manufactured by applying, drying, and pressing an anode active material on an anode current collector, and, if necessary, the above-described conductive material, organic binder polymer, filler, and the like may be selectively further included. [118] In addition, the negative electrode active material is, for example, graphite having a completely layered crystal structure such as natural graphite, soft carbon having a low crystalline layered crystal structure (graphene structure; a structure in which hexagonal honeycomb planes of carbon are arranged in layers) and carbon and graphite materials such as hard carbon, artificial graphite, expanded graphite, carbon fiber, non-graphitizable carbon, carbon black, carbon nanotube, fullerene, and activated carbon in which these structures are mixed with amorphous portions; LixFe 2 O 3 (0≤x≤1), LixWO 2 (0≤x≤1), SnxMe1-xMe'yOz (Me: Mn, Fe, Pb, Ge; Me', Al, B, P, Si, periodic table metal complex oxides such as Groups 1, 2, and 3 elements, halogens; 0