Abstract: A method and electrode assembly for evaluating performance of an electrode uses a negative electrode on which a negative electrode active material is applied to both surfaces of a negative electrode collector; a positive electrode on which a positive electrode active material is applied to both surfaces of a positive electrode collector and which is stacked with the negative electrode; two separators stacked between the negative electrode and the positive electrode; a reference electrode stacked between the two separators; and a second negative electrode stacked between the separator, which is relatively close to the negative electrode, of the two separators and the negative electrode.

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 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 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: Provided is a method for preparing an acrylic acid including: dehydrating a lactic acid aqueous solution in a reaction unit to prepare a reaction product stream; passing the reaction product stream through a cooling unit and a refining unit sequentially and supplying a discharge stream from the refining unit to an acrylic acid separation column; and separating an unreacted lactic acid as a side discharge stream and separating the acrylic acid as an upper discharge stream in the acrylic acid separation column.

Abstract: Provided is a method for preparing an acrylic acid, in which a lactic acid aqueous solution is dehydrated to prepare a reaction product stream, from which by-products are removed using an extraction column, an extractant recovery column, a first separation column, a second separation column, and a refining column to prepare a high-purity acrylic acid.

Abstract: Provided is a method for preparing an acrylic acid including: supplying a lactic acid aqueous solution to a reactor and performing a dehydration reaction to prepare a reaction product including an acrylic acid; supplying a reactor discharge stream including the reaction product to a first cooling tower and supplying an upper discharge stream from the first cooling tower to a second cooling tower; supplying a first acrylic acid aqueous solution stream discharged from a lower portion of the second cooling tower to an extraction column; supplying an upper discharge stream from the extraction column and a second acrylic acid aqueous solution stream discharged from a lower portion of the first cooling tower to a distillation column; and separating the acrylic acid from a lower discharge stream from the distillation column.

Abstract: Discussed is a lithium secondary battery and a method of manufacturing the lithium secondary battery. The lithium secondary battery may include an electrode assembly including a positive electrode, a negative electrode, and a separator positioned between the positive electrode and the negative electrode, wherein the negative electrode includes a negative electrode current collector and a negative electrode mixture layer, the negative electrode mixture layer being formed between the negative electrode current collector and the separator, and wherein a detection probe containing a metal oxide has a potential plateau of 1.3 V to 1.8 V is provided on a side surface of the negative electrode mixture layer.

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.

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 which includes a lithium-rich lithium manganese-based oxide containing at least lithium, nickel, manganese and molybdenum, wherein the lithium manganese-based oxide includes at least one primary particle and a molybdenum-containing flux is used to improve the crystal growth of the primary particle, resulting in mitigation and/or prevention of a decrease in stability caused by lithium and manganese present in excessive amounts in the lithium manganese-based oxide, and a lithium secondary battery including the same.

Abstract: A multilayer capacitor includes a body including a multilayer structure in which a plurality of dielectric layers are provided and a plurality of internal electrodes are stacked with the dielectric layer interposed therebetween and external electrodes disposed outside the body and connected to the plurality of internal electrodes. The body includes a high resistance portion disposed in at least one region between the dielectric layer and the internal electrode and inside the dielectric layer and having electric resistance higher than electric resistance of the internal electrode, and the high resistance portion and the plurality of internal electrodes include the same metal component and the same metal oxide component.

Abstract: Provided are a method for preparing an oligomer and an apparatus for preparing an oligomer. The method for preparing an oligomer includes performing an oligomerization reaction by feeding a feed stream containing a monomer to a reactor; feeding a first discharge stream of the reactor to a first separation device, and feeding a second discharge stream of the reactor to a second separation device; feeding a lower discharge stream of the second separation device to a third separation device; feeding an upper discharge stream containing the monomer of the third separation device to a monomer dissolution device and dissolving the upper discharge stream in a solvent fed to the monomer dissolution device; and feeding a discharge stream of the monomer dissolution device to the reactor.

Abstract: A method and electrode assembly for evaluating performance of an electrode uses a negative electrode on which a negative electrode active material is applied to both surfaces of a negative electrode collector; a positive electrode on which a positive electrode active material is applied to both surfaces of a positive electrode collector and which is stacked with the negative electrode; two separators stacked between the negative electrode and the positive electrode; a reference electrode stacked between the two separators; and a second negative electrode stacked between the separator, which is relatively close to the negative electrode, of the two separators and the negative electrode.

Abstract: Provided are a method for preparing an oligomer and an apparatus for preparing the same. The method for preparing an oligomer including: supplying a feed stream including a monomer to a reactor to perform an oligomerization reaction; supplying a first discharge stream from the reactor to a first separation device and supplying a second discharge stream from the reactor to a second separation device; recovering the monomer as an upper discharge stream from the second separation device and supplying a lower discharge stream from the second separation device to a third separation device; and supplying an upper discharge stream from the third separation device to the second separation device.

Abstract: A method and an apparatus for preparing an oligomer, the method including supplying a feed stream including a monomer to a reactor to perform an oligomerization reaction, recovering unreacted monomer, and dissolving the recovered unreacted monomer in a solvent in a monomer dissolution device and supplying a discharge stream from the monomer dissolution device to the reactor. The method and the apparatus provide reduced investment costs and improved economic feasibility as there is no need to use a refrigerant at a very low temperature or install a separate compressor to recover and reuse the unreacted monomer in an oligomer production process.

Abstract: A multilayer capacitor includes a body including a multilayer structure in which a plurality of dielectric layers are provided and a plurality of internal electrodes are stacked with the dielectric layer interposed therebetween and external electrodes disposed outside the body and connected to the plurality of internal electrodes. The body includes a high resistance portion disposed in at least one region between the dielectric layer and the internal electrode and inside the dielectric layer and having electric resistance higher than electric resistance of the internal electrode, and the high resistance portion and the plurality of internal electrodes include the same metal component and the same metal oxide component.

Abstract: Disclosed is a positive electrode for a lithium secondary battery, which includes: a positive electrode current collector; and a positive electrode active material layer including an upper layer portion and a lower layer portion, wherein each of the upper layer portion and the lower layer portion of the positive electrode active material layer includes a positive electrode active material, binder polymer and a conductive material, and the positive electrode active material has an electroconductivity of 0.0001-0.0004 S/cm, and the content of the conductive material contained in the lower layer portion is 10-59 parts by weight based on 100 parts by weight of the content of the conductive material contained in the upper layer portion, or the positive electrode active material has an electroconductivity of 0.008-0.

Abstract: Provided are a method for preparing an oligomer and an apparatus for preparing the same. The method for preparing an oligomer including: supplying a feed stream including a monomer to a reactor to perform an oligomerization reaction; supplying a first discharge stream from the reactor to a first separation device and supplying a second discharge stream from the reactor to a second separation device; recovering the monomer as an upper discharge stream from the second separation device and supplying a lower discharge stream from the second separation device to a third separation device; and supplying an upper discharge stream from the third separation device to the second separation device.