Abstract: The present invention relates to a negative electrode and a method for manufacturing the same. Specifically, the present invention provides a negative electrode comprising a current collector, a first active material layer formed on the current collector, and a second active material layer formed on the first active material layer, wherein the first active material layer comprises carbon-based negative electrode active material particles, and the second active material layer comprises silicon nitride. The negative electrode according to the present invention comprises a second active material layer comprising silicon nitride on a first active material layer. Nitrogen of the silicon nitride may react with lithium ions to form lithium nitride.

Abstract: The present invention relates to a method of preparing an electrode for a lithium secondary battery and an electrode for a lithium secondary battery prepared thereby, wherein, since the method may suppress the migration of a binder and may uniformly control the distribution of the binder in the electrode by forming a plurality of negative electrode active material layers and allowing a drying condition of each of the negative electrode active material layers to be different, the method may improve life characteristics by improving adhesion between a negative electrode active material and a current collector and may improve charging characteristics by reducing interfacial resistance of the negative electrode.

Abstract: A method for predicting a lifespan of a secondary battery within a short time in a more accurate and effective way is provided. The method for assessing a lifespan of a secondary battery includes primarily aging a prepared secondary battery for a predetermined time, initially charging the primarily aged secondary battery to a predetermined SOC and secondarily aging the initially charged secondary battery for a duration greater than the primary aging. Additionally, degassing removes gas in the secondarily aged secondary battery. Further, the method includes charging the secondary battery with a primary low-current at C-rate of 1/15 C or less, after the degassing step, discharging the secondary battery with a primary low-current at C-rate of 1/15 C or less, after the primary low-current charging step and determining a lifespan of the secondary battery by using a difference of voltages measured at different time points.

Abstract: The present disclosure relates to a positive electrode for a lithium secondary battery including an electrode current collector, and a positive electrode active material layer coated on at least a part of the electrode current collector, wherein the positive electrode active material layer includes a manganese-based positive electrode active material, and a porosity is from 30% to 35%, to improve high-temperature storage characteristics and high-temperature cycle characteristics.

Abstract: The present invention relates to a positive electrode for a secondary battery in which a maximum diameter of internal pores is controlled to be less than 1 ?m, a method of preparing the same, and a secondary battery including the positive electrode.

Abstract: An electrode mixture of the present invention comprises: an electrode active material; a binder; and a conductive material. When a cross-section of the electrode mixture is imaged such that a pixel filled 100% with a conductive material among a plurality of divided pixels is considered to be a condensed pixel and a value obtained by counting condensed pixels is considered to be the degree of agglomeration, the degree of agglomeration of a conductive material in the electrode mixture in the depth direction of the electrode mixture has a standard deviation less than 3.0. The electrode mixture as described above includes a conductive material uniformly distributed therein and thus has low electrode resistance. Therefore, the electrode mixture can improve output and lifespan properties of a lithium secondary battery to which the electrode mixture has been applied.

Abstract: The present disclosure provides a method for preparing a lithium secondary battery by bringing a first cell using a first cathode active material of formula (I) Li(LixMy?y?M?y?)O2?zAz??(I) wherein, x, y, y?, and z satisfy 0<x<0.5, 0.6<y<1.1, 0?y?<0.2, and 0?z<0.2, M is any one selected from the group consisting of Mn, Ni, Co, Fe, Cr, V, Cu, Zn, and Ti, M? is any one selected from the group consisting of Al, Mg and B; and A is any one selected from the group consisting of F, S and N and a second cell using a second cathode active material being generally used into activation under different voltage conditions, and then electrically connecting the first cell and the second cell in the step of assembling unit cells; and a lithium secondary battery prepared from the method.

Abstract: The present invention relates to an electrode for an electrochemical device and a method for manufacturing the same. More specifically, the present invention relates to an electrode for an electrochemical device having excellent electrolyte impregnation and improved battery output and lifecycle properties, and a method for manufacturing the electrode. The electrode according to the present invention enables an electrolyte to easily permeate into the electrode, thereby remarkably improving a lifecycle property or an output property due to high electrolyte impregnation. In addition, the method for manufacturing an electrode, according to the present invention, does not cause the deterioration of porosity of a lower electrode active material monolayer, the deterioration being caused by a step performed during the formation of an upper electrode active material monolayer.

Abstract: Disclosed herein is a cathode active material including a lithium manganese oxide, in which the lithium manganese oxide has a spinel structure with a predetermined constitutional composition represented by Formula 1 described in the detailed description, wherein a conductive material is applied to the surface of lithium manganese oxide particles, so as to exhibit charge-discharge properties in the range of 2.5 to 3.5V as well as in the 4V region.

Abstract: The present disclosure provides a method for removing gases generated in a lithium secondary battery using a cathode active material of the following formula (I) Li(LixMy?y?M?y?)O2?zAz??(I) wherein, x, y, y?, and z satisfy 0<x<0.5, 0.6<y?<1.1, 0?y?<0.2, and 0?z<0.2, M is any one selected from the group consisting of Mn, Ni, Co, Fe, Cr, V, Cu, Zn, and Ti, M? is any one selected from the group consisting of Al, Mg and B; and A is any one selected from the group consisting of F, S and N by carrying out two or more degassing steps under the conditions of above and below a voltage that the structural variation of the cathode active material occurs, thereby inducing a uniform initial reaction in a cathode and an anode to enhance the life time of the battery.

Abstract: Provided are a composition for a gel polymer electrolyte including i) an electrolyte solution solvent, ii) an ionizable lithium salt, iii) a polymerization initiator, and iv) a monomer having a functional group bondable to metal ions, and a lithium secondary battery including the composition for a gel polymer electrolyte. In a case where the composition for a gel polymer electrolyte of the present invention is used in a lithium secondary battery, since the movement of metal ions dissolved from a cathode to an anode may be prevented or the precipitation of metal on the anode may be reduced, the lifetime of the battery may not only be improved but capacity characteristics of the battery may also be excellent even in the case in which the battery is charged at a high voltage as well as normal voltage.

Abstract: Provided are a cathode active material composition including an xLi2MO3.(1?x)LiMeO2 composite (where 0<x<1, and M and Me represent metal ions and may be the same or different from each other) and a conductive polymer material, and a secondary battery including the cathode active material composition in a cathode. Since the conductivity of the secondary battery of the present invention may be improved, the cathode active material composition may improve life characteristics, output characteristics, and rate capability of the secondary battery.

Abstract: Provided are a method and an apparatus for rapidly charging a battery, such that a battery can be rapidly charged while having an extended lifetime. The method for charging a battery according to the present invention charges a battery by starting from an initial charging rate higher than 1 C, while stepwise decreasing the charging rate, such that a negative electrode potential of the battery does not drop to a level less than or equal to 0V. An occurrence of Li-plating of a negative electrode of the battery can be prevented by the criteria for preventing the negative electrode potential from dropping to a level less than or equal to 0V, thereby providing an effect of rapidly charging the battery while extending the lifetime of the battery.

Abstract: An electrode assembly, comprises one or more first electrodes comprising a cathode; one or more second electrodes comprising an anode; and a separator sheet having a zigzag form interposed therebetween. The separator sheet comprises a first porous polymer substrate; a first coating layer formed on one surface of the first porous polymer substrate and comprising a polymer binder, the first coating layer being faced with the cathode; and a second coating layer formed on the other surface of the first porous polymer substrate and comprising a mixture a polymer binder and inorganic particles, the second coating layer being faced with the anode and having a composition, a thickness and a porosity different from those of the first porous coating layer. A separator has porous coating layers with a different composition, thickness or porosity formed on each surface thereof.

Abstract: Disclosed is an electrode including an electrode comprising: an electrode current collector; and two or more electrode active material layers stacked on at least one surface of the electrode current collector, each of the electrode active material layers comprising an electrode active material, a conductor, and a binder, wherein the binder is uniformly distributed along a thickness direction of each of the electrode active material layer.

Abstract: Disclosed are a cathode active material for high voltage lithium secondary batteries and a lithium secondary battery including the same and, more particularly, the present invention relates to a cathode active material for lithium secondary batteries that includes a lithium transition metal oxide having a lithium molar fraction of greater than 1, containing a relative excess of nickel, and having a composition represented by Formula 1 below, wherein the lithium transition metal oxide has a Li2MnO3-like structure phase: Li1+aNibCocMn1?(a+b+c+d)MdO2-tAt??(1) wherein 0.05?a?0.2, 0.4?b?0.7, 0.1?c?0.4, 0?d?0.1, and 0?t<0.2; M is at least one divalent or trivalent metal; and A is at least one monovalent or divalent anion.

Abstract: Provided is a non-destructive method for detecting lithium plating by which lithium plating can be detected in real time in an actual use environment of a secondary battery, a secondary battery charging method and apparatus for charging a secondary battery under the condition in which lithium plating does not occur by using this method, and a secondary battery system for detecting the state of a secondary battery by using this method. The method for detecting lithium plating according to the present disclosure is a method which detects lithium plating in a negative electrode in real time by observing a change in battery voltage as a function of SOC during charging a secondary battery, and determines a point at which a rise speed of the battery voltage slows down as a lithium plating occurrence point.

Abstract: The present invention relates to a container for a stirrer used in a stirrer stirring objects through a centrifugal force. The container for the stirrer includes a container body of which the top is opened and in which a receiving space is formed, an outer lid coupled to the top of the container body, and a crushing unit including a supporting member disposed in the receiving space, and a crushing member extending outward from the supporting member and crushing and stirring the objects received in the receiving space. Thus, nanoparticle-sized objects can be rapidly crushed and stirred without agglomeration.

Abstract: A secondary battery having improved output characteristics is disclosed. The secondary battery according to the present invention accommodates a cell assembly including a plurality of cells connected in parallel, and an electrolyte together in one package, in which positive electrodes of a plurality of central cells disposed at a central part of the cell assembly have a loading energy density higher than that of positive electrodes of a plurality of side cells disposed at a side part, and the positive electrodes of the central cells have positive electrode material coating layers formed at surfaces thereof, which are thicker than those formed at surfaces of the positive electrodes of the side cells. Preferably, the total resistance of the side cells is lower than the total resistance of the central cells.

Abstract: The present invention relates to an optical film and method of manufacturing the same. The optical film of the present invention includes an acrylic resin and a core-shell type graft copolymer wherein the core includes a conjugate diene rubber, and the shell includes an acrylic monomer, an aromatic vinyl monomer, and a maleimide monomer.