摘要:
Provided is a lithium secondary battery having improved discharge characteristics in a range of high-rate discharge while minimizing a dead volume and at the same time, having increased cell capacity via increased electrode density and electrode loading amounts, by inclusion of two or more active materials having different redox levels so as to exert superior discharge characteristics in the range of high-rate discharge via sequential action of cathode active materials in a discharge process, and preferably having different particle diameters.
摘要:
Provided is a lithium secondary battery having improved discharge characteristics in a range of high-rate discharge while minimizing a dead volume and at the same time, having increased cell capacity via increased electrode density and electrode loading amounts, by inclusion of two or more active materials having different redox levels so as to exert superior discharge characteristics in the range of high-rate discharge via sequential action of cathode active materials in a discharge process, and preferably having different particle diameters.
摘要:
Disclosed is a method for preparing a lithium-metal composite oxide, the method comprising the steps of: (a) mixing an aqueous solution of one or more transition metal-containing precursor compounds with an alkalifying agent and a lithium precursor compound to precipitate hydroxides of the transition metals; (b) mixing the mixture of step (a) with water under supercritical or subcritical conditions to synthesize a lithium-metal composite oxide, and drying the lithium-metal composite oxide; and (c) subjecting the dried lithium-metal composite oxide either to calcination or to granulation and then calcination. Also disclosed are an electrode comprising the lithium-metal composite oxide, and an electrochemical device comprising the electrode. In the disclosed invention, a lithium-metal composite oxide synthesized based on the prior supercritical hydrothermal synthesis method is subjected either to calcination or to granulation and then calcination. Thus, unlike the prior dry calcination method or wet precipitation method, a uniform solid solution can be formed and the ordering of metals in the composite oxide can be improved. Accordingly, the lithium-metal composite oxide can show crystal stability and excellent electrochemical properties.
摘要:
Disclosed is a method for preparing a lithium-metal composite oxide, the method comprising the steps of: (a) mixing an aqueous solution of one or more transition metal-containing precursor compounds with an alkalifying agent and a lithium precursor compound to precipitate hydroxides of the transition metals; (b) mixing the mixture of step (a) with water under supercritical or subcritical conditions to synthesize a lithium-metal composite oxide, and drying the lithium-metal composite oxide; and (c) subjecting the dried lithium-metal composite oxide either to calcination or to granulation and then calcination. Also disclosed are an electrode comprising the lithium-metal composite oxide, and an electrochemical device comprising the electrode. In the disclosed invention, a lithium-metal composite oxide synthesized based on the prior supercritical hydrothermal synthesis method is subjected either to calcination or to granulation and then calcination. Thus, unlike the prior dry calcination method or wet precipitation method, a uniform solid solution can be formed and the ordering of metals in the composite oxide can be improved. Accordingly, the lithium-metal composite oxide can show crystal stability and excellent electrochemical properties.
摘要:
The present invention relates to a lithium-containing metal composite oxide comprising paramagnetic and diamagnetic metals, which satisfies any one of the following conditions: (a) the ratio of intensity between a main peak of 0±10 ppm (I0ppm) and a main peak of 240±140 ppm (I240ppm), (I0ppm/I240ppm), is less than 0.117·Z wherein z is the ratio of moles of the diamagnetic metal to moles of lithium; (b) the ratio of line width between the main peak of 0±10 ppm (I0ppm) and the main peak of 240±140 ppm (I240ppm), (W240ppm/W0ppm), is less than 21.45; and (c) both the conditions (a) and (b). The peaks of the lithium-containing metal composite oxide are obtained according to the 7Li—NMR measurement conditions and means disclosed herein.
摘要:
Disclosed is a lithium-containing metal composite oxide comprising paramagnetic and diamagnetic metals, which satisfies any one of the following conditions: (a) the ratio of intensity between a main peak of 0±10 ppm (Io PPm) and a main peak of 240±140 ppm (I240 pPm), Uoppm/124o PPm), is less than 0.117·Z wherein Z is the ratio of moles of the diamagnetic metal to moles of lithium; (b) the ratio of line width between the main peak of 0±10 ppm (Io PPm) and the main peak of 240+140 ppm (I24o PPm), (W24o PPm/WO ppm), is less than 21.45; and (c) both the conditions (a) and (b), the peaks being obtained according to the 7Li—NMR measurement conditions and means disclosed herein. Also, an electrode comprising the lithium-containing metal composite oxide, and an electrochemical device comprising the electrode are disclosed. The lithium-containing multicomponent metal composite oxide shows crystal stability and excellent physical properties as a result of an improved ordering structure of metals, in which the components of the composite oxide are uniformly distributed. Thus, it can provide a battery having high capacity characteristics, long cycle life characteristics and improved rate characteristics.
摘要:
Provided is an electrode mix for a secondary battery containing an electrode active material, comprising a PVA having a degree of polymerization of more than 2500 and a degree of saponification of more than 90% as a binder, and a lithium secondary battery comprising the same. Use of the binder according to the present invention can provide advantageous effects such as improved adhesive strength between the electrode mix and current collector and between the electrode mixes, prevention of the peeling and separation of the active material even after repeated charge/discharge cycles, and inhibition of decreases in the capacity or output power retention rate of the secondary battery.
摘要:
Provided is an electrode mix for a secondary battery containing an electrode active material, comprising a PVA having a degree of polymerization of more than 2500 and a degree of saponification of more than 90% as a binder, and a lithium secondary battery comprising the same. Use of the binder according to the present invention can provide advantageous effects such as improved adhesive strength between the electrode mix and current collector and between the electrode mixes, prevention of the peeling and separation of the active material even after repeated charge/discharge cycles, and inhibition of decreases in the capacity or output power retention rate of the secondary battery.
摘要:
A thin film transistor including: an active layer formed on a substrate; a gate insulating layer pattern formed on a predetermined region of the active layer; a gate electrode formed on a predetermined region of the gate insulating layer pattern; an etching preventing layer pattern covering the gate insulating layer pattern and the gate electrode; and a source member and a drain member formed on the active layer and the etching preventing layer pattern.
摘要:
The present invention provides a method for preparing spherical carbon comprising step of heat-treating a mixture of a carbon precursor and dispersion media, a spherical non-graphitizable carbon using the same, and a method for preparing spherical artificial graphite.