【TECHNICAL FIELD】 This application claims priority to and the benefit of the benefit of Korean Patent Application No. 10-2015-0145803 filed on October 20, 2015 with the Korean Intellectual Property Office, the disclosure of which is 10 incorporated herein by reference in its entirety. The present invention relates to a precursor for the production of a positive electrode active material comprising metal oxides having a multilayered structure, and a positive electrode active material for lithium secondary battery produced using the same. 15 【BACKGROUND OF ART】 Due to the rapid increase in the use of fossil fuels, the demand for the use of alternative energy and clean energy is increasing, and in a bid to meet the demand, the fields of electric power generation and electric energy 20 3 storage using electric chemistry are most actively studied. As a representative example of electrochemical devices using electrochemical energy, secondary batteries are currently used and application thereof is gradually expanding. Recently, as technology for portable devices, such as portable 5 computers, portable phones, cameras, and the like, continues to develop and demand therefor continues to increase, demand for secondary batteries as energy sources is rapidly increasing. Among these secondary batteries, research on lithium secondary batteries having high energy density, high operating potential, long cycle lifespan and low self-discharge rate has been 10 underway and such lithium secondary batteries are commercially available and widely used. As the lithium secondary battery, lithium-containing cobalt oxide (LiCoO2) is mainly used, and in addition, the use of lithium-containing manganese oxide such as LiMnO2 having a layered crystal structure and LiMn2O4 15 having a spinel crystal structure and lithium-containing nickel oxide (LiNiO2) is also considered. As the positive electrode active material of a lithium secondary battery, lithium-containing cobalt oxide (LiCoO2) is mainly used, and in addition, the use of lithium-containing manganese oxide such as LiMnO2 having 20 4 a layered crystal structure and LiMn2O4 having a spinel crystal structure and lithium-containing nickel oxide (LiNiO2) is also considered. Among the above-mentioned positive electrode active materials, LiCoO2 has excellent lifespan characteristics and charge/discharge efficiency and thus is most frequently used, but it has disadvantages that high temperature 5 safety is lowered, and cobalt used as a raw material is expensive due to its resource restriction and thus there is a limit in price competition aspect. Lithium manganese oxides such as LiMnO2 and LiMn2O4 are advantageous in that they are excellent in thermal stability, and they are inexpensive and easy to synthesize, but there are problems that the capacity is small, the 10 high temperature characteristics are poor, and the conductivity is low. In addition, LiNiO2-based positive electrode active material is relatively inexpensive and shows battery characteristics such as high discharging capacity, but exhibits sudden phase transition of the crystal structure in accordance with volume change accompanying charge/discharge 15 cycles. Further, there is a problem that the stability is abruptly lowered when exposed to air and moisture. Therefore, recently, a lithium transition metal oxide in which a part of nickel is substituted with another transition metal such as manganese or cobalt has been proposed as an alternative material. However, such metal-20 5 substituted nickel-based lithium-transition metal oxides have an advantage in that they have relatively excellent cycle characteristics and capacity characteristics. However, even in this case, the cycle characteristics are drastically lowered when used for a long period of time, and problems such as swelling due to gas generation of the battery and deterioration of thermal 5 stability due to low chemical stability are not sufficiently solved. Therefore, there is a high need for a positive electrode active material capable of solving the thermal stability problem even while exhibiting improved capacity and output characteristics. 10 【DETAILED DESCRIPTION OF THE INVENTION】 【Technical Problem】 The present invention in some embodiments seeks to resolve the above-described deficiencies of the prior art and the technical issues long outstanding in the art. 15 As a result of a variety of extensive and intensive studies and experiments to solve the problems as described above, the present inventors have found that, as described later, when a precursor for producing a positive electrode active material for a secondary battery is formed in a structure including a core composed of transition metal hydroxides including 20 6 nickel(Ni) and manganese(Mn), or transition metal hydroxides including nickel(Ni), manganese(Mn) and cobalt(Co), and a shell composed of transition metal hydroxides including cobalt(Co), a positive electrode active material having a structure including a core composed of nickel-rich lithium transition metal oxides and a shell composed of cobalt-rich lithium 5 transition metal oxides can be produced; and thus such positive electrode active material can exert only merits of the compounds of each of the core and the shell and maintain the thermal stability while exhibiting high capacity and excellent high output characteristics, thereby completing the present invention. 10 【Technical Solution】 In order to achieve the above objects, a precursor for the production of a positive electrode active material for a secondary battery according to the present invention comprises: 15 a core composed of transition metal hydroxides including nickel(Ni) and manganese(Mn), or transition metal hydroxides including nickel(Ni), manganese(Mn) and cobalt(Co); and a shell composed of transition metal hydroxides including cobalt(Co). Generally, in the process of charging and discharging, the crystal 20 7 structure is irreversibly changed due to a decrease in the structural stability of the positive electrode active material, and side reactions occur in which the elution of transition metal and the release of oxygen occur simultaneously. In particular, the nickel-rich lithium transition metal oxides have relatively low structural stability but are relatively superior 5 in capacity and resistance/output characteristics. In addition, the cobalt-rich lithium transition metal oxide is excellent in lifespan characteristics and charge/discharge efficiency and exhibits excellent high power output characteristics, but it has a disadvantage that its high-temperature safety is deteriorated. 10 Therefore, the precursor for the production of the positive electrode active material for a secondary battery according to the present invention is formed in a structure including a core composed of transition metal hydroxides including nickel(Ni) and manganese(Mn), or transition metal hydroxides including nickel(Ni), manganese(Mn) and cobalt(Co), and a shell 15 composed of transition metal hydroxides including cobalt(Co), thereby producing a positive electrode active material having a structure including a core composed of nickel-rich lithium transition metal oxides and a shell composed of cobalt-rich lithium transition metal oxides, and such positive electrode active material can supplement defects of the compounds of the core 20 8 and the shell from each other and exert only merits of each compound, thereby maintaining the thermal stability while exhibiting high capacity and excellent high output characteristics. In one specific embodiment, in order to enhance the structural stability of the positive electrode active material produced using the above 5 precursor, at least one or more of the transition metals in the transition metal hydroxides can substituted with one or more metals having a valence of +2 or +3 within a predetermined amount range, and more specifically, the transition metal hydroxides of the core and the transition metal oxide of the shell may further include one or more doping elements which are in each 10 case mutually independently selected from the group consisting of tungsten(W), boron(B), aluminum(Al), zirconium(Zr), titanium(Ti), magnesium(Mg), chromium(Cr ), and silicon(Si). Specifically, the transition metal hydroxide of the core may be a compound represented by the following Formula 1, and the transition metal 15 hydroxide of the shell may be a compound represented by the following Formula 2. NiaMnbCo1-(a+b+c)Mc(OH1-x)2 (1) wherein, 0.55≤a≤0.9, 0.05≤b≤0.5, 0≤c≤0.1, a+b+c≤1, 0 (Production of Precursor for Production of Positive Electrode Active Material) In order to produce a precursor for the production of a positive electr15 ode active material for a secondary battery, first, 2L of distilled water was filled in a 3 L wet-type reactor tank, and then nitrogen gas was continuously injected into the tank at a rate of 1 L/min to remove dissolved oxygen. At this time, the temperature of the distilled water in the tank was maintained at 45 to 50℃20 23 by using a temperature maintaining device. Further, the distilled water in the tank was stirred with speeds in the range of 1000-1200 rpm using an impeller connected to a motor installed outside the tank. Nickel sulfate, manganese sulfate, and cobalt sulfate were mixed at a ratio (molar ratio) of 0.55:0.25:0.2 to prepare a 1.5M transition metal 5 aqueous solution. In addition, a 3M sodium hydroxide aqueous solution was also prepared. The transition metal aqueous solution was added at a rate of 0.3 L/hr to a wet-type reactor maintained at 45 to 50°C and containing distilled water, and a salt containing zirconium (Zr) as a doping element was added. The prepared sodium hydroxide aqueous solution was added so that the 10 distilled water in the wet-type reactor was maintained at a pH of 11.0 to 12.5. A 30% ammonia solution as an additive was continuously to the wet-type reactor at a rate of 0.035 L to 0.04 L/hr. The mixture was stirred using an impeller speed of 1100 rpm, and then the transition metal aqueous solution, the sodium hydroxide aqueous solution and the ammonia solution were added by 15 adjusting their flow rates such that the average residence time of the solutions in the wet-type reactor was about 5 hours. After the reaction in the reactor arrived at a steady state, a certain duration of time was given to obtain an oxide with a high density. Then, transition metal hydroxide (Ni0.55Mn0.3Co0.1Zr0.05(OH0.53)2) was synthesized. 20 24 To the transition metal hydroxide (Ni0.55Mn0.3Co0.1Zr0.05(OH0.53)2) synthesized in the wet-type reactor, a 2M transition metal aqueous solution containing cobalt sulfate, a salt containing zirconium(Zr) as a doping element, a sodium hydroxide aqueous solution and an ammonia solution were added by adjusting their flow rates such that the average residence time of 5 the solutions in the wet-type reactor was about 2 hours. At this time, the supply of gas was replaced by nitrogen gas to make a reducing atmosphere. A 4M sodium hydroxide solution was added so as to maintain at a pH of 11. After the arrival of a steady state, a certain duration of time was given to obtain an oxide with high density. Subsequently, a shell layer composed of 10 transition metal hydroxide Co0.95Zr0.05(OH0.53)2 was formed on the core composed of Ni0.55Mn0.3Co0.1Zr0.05(OH0.53)2 to obtain a precursor having a core-shell structure. (Production of Positive Electrode Active Material) 15 The precursor obtained by the reactor was washed with distilled water, filtered, and dried in a constant temperature drier at 120°C for 24 hours to remove residual moisture. The thus dried precursor having a core-shell structure and Li2CO3 were mixed at a weight ratio of 1:1, and the mixture was heated at a heating rate of 5°C/min and calcined at 920°C for 10 hours to 20 25 obtain a lithium transition metal oxide powder (positive electrode active material). Thereby, the positive electrode active material powder having a core-shell structure in which the core layer of the positive electrode active material was composed of Li[Ni0.55Mn0.3Co0.1Zr0.05]O2, and the shell layer was composed of 5 LiCo0.95Zr0.05O2, wherein the content ratio of the core and the shell was 40:60 on a weight basis, was obtained. (Production of lithium secondary battery) The previously prepared positive electrode active material was mixed 10 with a conductive material and a binder (PVdF) at a ratio of 95: 2.5: 2.5 (weight ratio of active material, conductive material and binder) and the mixture was added to NMP (N-methyl-2-pyrrolidone) as a solvent to prepare a positive electrode mixture slurry. 95 wt% of an artificial graphite as a negative electrode active material, 1.5 wt% of a conductive material (Super-P) 15 and 3.5 wt% of a binder (PVdF) were added to a solvent NMP to prepare a negative electrode mixture slurry. Then, coating, drying and pressing were respectively carried out on the aluminum foil and the copper foil to produce a positive electrode and a negative electrode. A porous polyethylene separator was interposed between the positive 20 26 electrode and the negative electrode, and then an electrolytic solution in which 1 M LiPF6 was dissolved in a carbonate solvent having EC: EMC = 1:2 was injected to produce a coin battery. 5 A battery was produced in the same manner as in Example 1, except that a 1.5M transition metal aqueous solution was prepared by mixing nickel sulfate, manganese sulfate, and cobalt sulfate at a ratio (molar ratio) of 0.6: 0.2: 0.2. 10 A battery was produced in the same manner as in Example 1, except that a salt containing zirconium (Zr) as a doping element was not supplied during the production of a precursor for the production of a positive electrode active material for a secondary battery. 15 A battery was produced in the same manner as in Example 1, except that a positive electrode active material powder having a structure in which compound particles of Li[Ni0.55Mn0.3Co0.1Zr0.05]O2 and compound particles of 20 27 LiCo0.95Zr0.05O2 were uniformly mixed was prepared, instead of preparing a positive electrode active material powder having a core-shell structure. A battery was produced in the same manner as in Example 1, except that 5 the content ratio of the core and the shell in the positive electrode active material for the secondary battery was 10:90 on a weight basis. A battery was produced in the same manner as in Example 1, except that 10 the content ratio of the core and the shell in the positive electrode active material for the secondary battery was 90:10 on a weight basis. Lifespan characteristics 15 The coin batteries respectively produced in Examples 1 to 4 and Comparative Examples 1 to 3 were charged and discharged 100 times with a current of 0.5 C in a voltage range of 3.0V to 4.4V to evaluate the lifespan characteristics. The results are shown in Table 1 below. 【Table 1】 20 28 Sample lifespan characteristic 30th/1st discharging capacity (%) Example 1 98% Example 2 97% Example 3 96% Comparative Example 1 93% Comparative Example 2 92% Comparative Example 3 92% As shown in Table 1, it was confirmed that the lithium secondary battery using the positive electrode active material of the core-shell structure produced in Examples 1 to 3 according to the present invention exhibited a high capacity maintenance rate as compared with the lithium secondary batteries of Comparative Examples 1 to 3. 5 High-Speed Charging Characteristics 29 The coin batteries respectively produced in Examples 1 to 3 and Comparative Examples 1 to 3 were charged and discharged with a current of 0.1C in a voltage range of 3.0V to 4.4V and then charged and discharged with a current of 5.0C to evaluate high-speed charging characteristics. The results are shown in Table 2 below. 5 【Table 2】 Sample 0.1C charging capacity (mAh/g) 5C charging capacity (mAh/g) High-speed charging efficiency 5.0C/0.1C (%) Example 1 184 165 90 Example 2 186 168 90 Example 3 185 161 87 Comparative Example 1 184 155 84 Comparative Example 2 185 152 82 Comparative Example 3 181 151 85 As shown in Table 2, it was confirmed that the lithium secondary 30 batteries produced from Examples 1 to 3 according to the present invention exhibited high output characteristics as compared with the lithium secondary batteries of Comparative Examples 1 to 3. As described above, the precursor for the production of the positive electrode active material for a secondary battery according to the present 5 invention is formed in a structure including a core composed of transition metal hydroxides including nickel(Ni) and manganese(Mn), or transition metal hydroxides including nickel(Ni), manganese(Mn) and cobalt(Co), and a shell composed of transition metal hydroxides including cobalt(Co), thereby producing a positive electrode active material having a structure including a 10 core composed of nickel-rich transition metal oxides and a shell composed of cobalt-rich lithium transition metal oxides, and such positive electrode active material can supplement defects of the compounds of the core and the shell from each other and exert only merits of each compound, thereby maintaining the thermal stability while exhibiting high capacity and 15 excellent high output characteristics. Various changes and modifications within the sprit and scope of the invention will become apparent to those skilled in the art from this detailed description. 20 31 【Industrial Applicability】 As described above, the precursor for the production of the positive electrode active material for a secondary battery according to the present invention is formed in a structure including a core composed of transition metal hydroxides including nickel(Ni) and manganese(Mn), or transition metal 5 hydroxides including nickel(Ni), manganese(Mn) and cobalt(Co), and a shell composed of transition metal hydroxides including cobalt(Co), thereby producing a positive electrode active material having a structure including a core composed of nickel-rich transition metal oxides and a shell composed of cobalt-rich lithium transition metal oxides, and such positive electrode 10 active material can supplement defects of the compounds of the core and the shell from each other and exert only merits of each compound, thereby maintaining the thermal stability while exhibiting a high capacity and excellent high output characteristics. WHAT IS CLAIMED IS: 【Claim 1】 A precursor for the production of a positive electrode active material for a secondary battery comprising: a core composed of transition metal hydroxides including nickel(Ni) and 5 manganese(Mn), or transition metal hydroxides including nickel(Ni), manganese(Mn) and cobalt(Co); and a shell composed of transition metal hydroxides including cobalt(Co). 【Claim 2】 The precursor for the production of a positive electrode active 10 material according to claim 1, wherein the transition metal hydroxide of the core and the transition metal hydroxide of the shell further includes one or more doping elements which are in each case mutually independently selected from the group consisting of tungsten(W), boron(B), aluminum(Al), zirconium(Zr), titanium(Ti), magnesium(Mg), chromium(Cr ), and silicon(Si). 15 【Claim 3】 The precursor for the production of a positive electrode active material according to claim 1, wherein the transition metal hydroxide of the core is a compound represented by the following Formula 1, and the transition metal hydroxide of the shell may be a compound represented by the following 20 33 Formula 2. NiaMnbCo1-(a+b+c)Mc(OH1-x)2 (1) wherein, 0.55≤a≤0.9, 0.05≤b≤0.5, 0≤c≤0.1, a+b+c≤1, 0