Abstract: The present invention relates to a positive electrode active material and a lithium secondary battery including the same, and more particularly, to a positive electrode active material including an overlithiated lithium manganese-based oxide, which is capable of preventing the electrochemical properties of a lithium secondary battery, including rate characteristics, from being degraded due to an excess of lithium and manganese in the lithium manganese-based oxide, and particularly preventing the lifetime degradation of a lithium secondary battery by inhibiting or mitigating the elution of a transition metal from the lithium manganese-based oxide, and a lithium secondary battery including the same.

Abstract: The present invention relates to a lithium secondary battery, and more particularly, to a lithium secondary battery which has an improved capacity and lifetime maintenance rate by controlling a voltage range during formation or operation of the lithium secondary battery. In addition, the present invention relates to a lithium secondary battery in which the degradation of the electrochemical properties of a lithium secondary battery, including rate capability, caused by an excess of lithium and manganese in the lithium manganese-based oxide used as a positive electrode active material, is prevented, and particularly, the lifetime deterioration is prevented by inhibiting or mitigating the dissolution of a transition metal from the lithium manganese-based oxide.

Abstract: The present invention relates to a positive electrode active material and a lithium secondary battery including the same, and more particularly, to a positive electrode active material including an overlithiated lithium manganese-based oxide, wherein through surface modification of the lithium manganese-based oxide, the surface resistance of the lithium manganese-based oxide is reduced, thereby improving the lifetime characteristics of the lithium secondary battery, which uses the lithium manganese-based oxide as a positive electrode active material, and a lithium secondary battery including the same.

Abstract: The present invention relates to a positive electrode active material and a lithium secondary battery including the same, and more particularly, to a positive electrode active material including an overlithiated lithium manganese-based oxide, which can be synthesized at a lower temperature than that in a conventional synthesis process, and compensate for phase development and lithium ion conductivity, which are insufficient when synthesized at low temperatures, and a lithium secondary battery including the same.

Abstract: The present invention relates to a positive electrode active material and a lithium secondary battery including the same, and more particularly, to a bimodal-type positive electrode active material, in which low energy density per unit volume and low stability of an overlithiated lithium manganese-based oxide are improved, and a lithium secondary battery including the same.

Abstract: The present invention relates to a positive electrode active material and a lithium secondary battery including the same, and more particularly, to a positive electrode active material including an overlithiated lithium manganese-based oxide, which can improve the electrochemical properties of a lithium secondary battery including discharge capacity and rate performance, which are reduced by lithium and manganese present in excess in the lithium manganese-based oxide, and a lithium secondary battery including the same.

Abstract: The present invention relates to a positive electrode active material and a lithium secondary battery including the same, and more particularly, to a positive electrode active material which includes an overlithiated lithium manganese-based oxide including at least lithium, nickel, manganese and a doping metal, and in which the degradation in stability caused by excessive amounts of lithium and manganese in the lithium manganese-based oxide is mitigated and/or prevented by controlling the concentration of a transition metal in the lithium manganese-based oxide for each region, and a lithium secondary battery including the same.

Abstract: The present invention relates to a positive electrode active material and a lithium secondary battery including the same, and more particularly, to a positive electrode active material including an overlithiated lithium manganese-based oxide, which can prevent a rapid decrease in the lifetime of the lithium secondary battery by suppressing and mitigating the elution of transition metals from the lithium manganese-based oxide and reduce gas generation due to side reactions in the battery, and a lithium secondary battery including the same.

Abstract: The present invention relates to a positive electrode active material and a lithium secondary battery including the same, and more particularly, to a positive electrode active material which includes an overlithiated lithium manganese-based oxide including at least lithium, nickel, manganese and a doping metal, and in which the degradation in stability caused by excessive amounts of lithium and manganese in the lithium manganese-based oxide is mitigated and/or prevented by controlling the concentration of a transition metal in the lithium manganese-based oxide for each region, and a lithium secondary battery including the same.

Abstract: The present invention relates to a positive electrode active material and a lithium secondary battery including the same, and more particularly, to a positive electrode active material including an overlithiated lithium manganese-based oxide, and capable of preventing the degradation in electrochemical properties of a lithium secondary battery, including rate characteristics, caused by an excess of lithium and manganese in the lithium manganese-based oxide, and particularly reducing side reactions between the lithium manganese-based oxide and a liquid electrolyte during high-voltage operation, and a lithium secondary battery including the same.

Abstract: The present invention relates to a positive electrode active material and a lithium secondary battery including the same, and more particularly, to a positive electrode active material including an overlithiated lithium manganese-based oxide, and capable of preventing the degradation of electrochemical properties of a lithium secondary battery, including rate characteristics, caused by an excess of lithium and manganese in the lithium manganese-based oxide and reducing side reactions between the lithium manganese-based oxide and a liquid electrolyte during high-voltage operation through induction of the growth of primary particles constituting the lithium manganese-based oxide.

Abstract: The present invention relates to a positive electrode active material and a lithium secondary battery including the same, and more particularly, to a positive electrode active material including an overlithiated lithium manganese-based oxide, and capable of preventing the electrochemical properties of a lithium secondary battery, including rate characteristics, from deteriorating due to lithium and manganese being present in excess in the lithium manganese-based oxide and reducing side reactions between the lithium manganese-based oxide and a liquid electrolyte during high-voltage operation by inducing the growth of a primary particle constituting the lithium manganese-based oxide, and a lithium secondary battery including the same.

Abstract: The present invention relates to a positive electrode active material and a lithium secondary battery including the same, and more particularly, to a bimodal-type positive electrode active material for improving the low energy density per unit volume of an overlithiated lithium manganese-based oxide and a lithium secondary battery including the same.

Abstract: The present invention relates to a positive electrode active material and a lithium secondary battery including the same, and more particularly, to a bimodal-type positive electrode active material which is capable of improving the low energy density per unit volume of an overlithiated lithium manganese-based oxide, preventing the degradation of electrochemical properties of a lithium secondary battery, including rate characteristics, caused by an excess of lithium and manganese in the lithium manganese-based oxide, and particularly preventing the lifetime deterioration of a lithium secondary battery by inhibiting or mitigating the release of a transition metal from the lithium manganese-based oxide, and a lithium secondary battery including the same.

Abstract: The present invention relates to a positive electrode active material and a lithium secondary battery including the same, and more particularly, to a positive electrode active material including an overlithiated lithium manganese-based oxide, which is able to prevent the degradation of the electrochemical properties of a lithium secondary battery, including rate characteristics, caused by an excess of lithium and manganese in the lithium manganese-based oxide by inducing the growth of primary particles constituting the lithium manganese-based oxide, and prevent the lifetime deterioration of a lithium secondary battery by reducing side reactions between the lithium manganese-based oxide and a liquid electrolyte particularly during high-voltage operation, and at the same time, inhibiting or mitigating the release of a transition metal from the lithium manganese-based oxide, and a lithium secondary battery including the same.

Abstract: The present invention relates to a positive electrode active material and a lithium secondary battery including the same, and more particularly, to a positive electrode active material including an overlithiated lithium manganese-based oxide, and capable of preventing the degradation in electrochemical properties of a lithium secondary battery, including rate characteristics, caused by an excess of lithium and manganese in the lithium manganese-based oxide, and particularly reducing side reactions between the lithium manganese-based oxide and a liquid electrolyte during high-voltage operation, and a lithium secondary battery including the same.

Abstract: A positive electrode active material for a secondary battery according to an embodiment of the present invention comprises a lithium composite oxide represented by chemical formula 1 below and containing a layer-structured lithium excess oxide, wherein the lithium composite oxide comprises a secondary particle; the secondary particle comprises at least one primary particle; the primary particle comprises at least one crystallite; at least any one selected from the secondary particle, the primary particle, and the crystallite comprises a core and a shell occupying at least a portion of the surface of the core; and when the crystal structure belonging to space group C2/m is designated as [C2/m], the crystal structure belonging to space group R-3m is designated as [R-3m], and the ratio of the crystal structure belonging to space group C2/m versus the crystal structure belonging to space group R-3m is designated as [C2/m]/[R-3m], the [C2/m]/[R-3m] of the core differs from that of the shell in the secondary partic

Abstract: A cathode active material for a lithium secondary battery, according to an embodiment of the present invention, comprises a lithium composite oxide comprising a lithium-rich layered oxide, which is represented by the following chemical formula 1, wherein the lithium composite oxide comprises secondary particles, each of the secondary particles comprises one or more primary particles, each of the primary particles comprises one or more crystallites, at least any one selected from among the secondary particles, the primary particles and the crystallites comprises a core and a shell, which occupies a part of the surface of the core, and, when the mole of at least any one element selected from among nickel (Ni), cobalt (Co) and manganese (Mn) to the total mole of M1 and M2 in the following chemical formula 1 are NCM/M, the NCM/M of the shell and the core in the secondary particles are different from each other.

Abstract: A positive electrode active material for a secondary battery according to an embodiment of the present invention comprises a lithium composite oxide represented by chemical formula 1 and containing a layer-structured lithium excess oxide, wherein the lithium composite oxide comprises a secondary particle; the secondary particle comprises at least one primary particle; the primary particle comprises at least one crystallite; at least one selected from the secondary particle, the primary particle, and the crystallite comprises a core and a shell occupying at least a portion of the surface of the core; and when the number of moles of at least one element having an oxidation number, selected from among nickel (Ni), cobalt (Co) and manganese (Mn) relative to the total number of moles of M1 and M2 in chemical formula 1 is Mp+/M, the Mp+/M in the core differs from that in the shell in the secondary particle: [Chemical formula 1] rLi2M1O3(1-r) LiaM2O2.

Abstract: The present invention relates to a positive electrode active material and a lithium secondary battery including the same, and more particularly, to a positive electrode active material, which includes an overlithiated lithium manganese-based oxide, which is a solid solution with a phase belonging to a C2/m space group and a phase belonging to an R3-m space group and in which stability degradation caused by excessive amounts of lithium and manganese in the lithium manganese-based oxide is mitigated and/or prevented because there are regions with different proportions of the phase belonging to the C2/m space group and the phase belonging to the R3-m space group in the lithium manganese-based oxide, and a lithium secondary battery including the same.