Sk on Co., Ltd.

Electronics and Telecommunications Research Institute

Sk Innovation Co., Ltd.

Postech Academy-industry Foundation

Korea Research Institute of Bioscience and Biotechnology

Seoul Opto Device Co., Ltd.

Sang Han Lee

Yong Hyun Cho

Min Gu Kang

Jeong Bae Yoon

Seong-Min Kim

Ho Jin Lee

In Kui Cho

Jung Ick Moon

Sang-Won Kim

Sang Wook Lee

Jong Lam Lee

Min Suk Kang

Jong Hyuk Lee

In Haeng Cho

Hae Suk Hwang

Tae Sook Jeong

Mun-Chual Rho

Hae Yong Yang

Sangku Lee

Dong Wook Ha

Jae Sun Moon

Sung Uk Kim

Kyung Hoon Lee

Yoon Ji Lee

Byoung Beom Lim

Ju Ryoung Kim

Eui Il Hwang

A cathode for a lithium secondary battery includes a cathode current collector, and a cathode active material layer including a first cathode active material layer and a second cathode active material layer sequentially stacked on the cathode current collector. The first cathode active material layer includes first cathode active material particles having a secondary particle structure, and the second cathode active material layer includes second cathode active material particles having a single particle shape. A ratio of a SPAN value of the second cathode active material particles relative to a SPAN value of the first cathode active material particles is in a range from 2 to 4.5.

Cathode for lithium secondary battery and lithium secondary battery including the same

A cathode for a lithium secondary battery includes a cathode current collector, and a cathode active material layer on the cathode current collector. The cathode active material layer includes a plurality of a lithium-metal oxide particle that has a shape of a single particle. An activation energy (Ea) of the cathode is in a range from 50 kJ/mol to 80 kJ/mol.

Method of preparing cathode active material, cathode for lithium secondary battery and lithium secondary battery

A cathode active material for a lithium secondary battery including a lithium-transition metal composite oxide particle is provided. A crystal grain size of the lithium-transition metal composite oxide particle measured by an XRD analysis is 250 nm or more, and an XRD peak intensity ratio of the lithium-transition metal composite oxide particle is 9.8% or less. A lithium secondary battery including the lithium-transition metal composite oxide particle and having improved life-span and rate capability is provided.

Cathode active material for lithium secondary battery and lithium secondary battery including the same

A positive electrode active material may include a lithium layer doped with a first doping element and a transition metal layer doped with a second doping element. An I(003)/I(006) peak intensity ratio in X-ray diffraction measurement is equal to or less than 23.8.

Positive electrode active material, manufacturing method thereof, and positive electrode for lithium secondary battery comprising the same

A lithium secondary battery according to an embodiment of the present invention includes an electrode assembly including a separation layer, and a plurality of cathodes and a plurality of anodes separated by the separation layer and repeatedly stacked, and a gas adsorption layer coated on a single surface of an outermost anode among the plurality of anodes.

Lithium secondary battery

A cathode active material for a lithium secondary battery includes a lithium-transition metal composite oxide particle having a lattice strain (η) of 0.18 or less, which is calculated by applying Williamson-Hall method defined by Equation 1 to XRD peaks measured through XRD analysis, and having an XRD peak intensity ratio of 8.9% or less, which is defined by Equation 2. By controlling the lattice strain and XRD peak intensity ratio of the lithium-transition metal composite oxide particle, a lithium secondary battery with improved life-span characteristics as well as output characteristics is provided.

A cathode active material for a lithium secondary battery includes a lithium-transition metal composite oxide particle having a lattice strain (&#x3b7;) of 0.18 or less, which is calculated by applying Williamson-Hall method defined by Equation 1 to XRD peaks measured through XRD analysis, and having an XRD peak intensity ratio of 8.9% or less, which is defined by Equation 2. By controlling the lattice strain and XRD peak intensity ratio of the lithium-transition metal composite oxide particle, a lithium secondary battery with improved life-span characteristics as well as output characteristics is provided.

A receiver of a wireless power transmission system may include a capacitor-and-inductor configured to receive power from a transmitter using a resonance, at least one capacitor configured to connect to an output node of the receiver, and a plurality of switches configured to control current flow within the receiver. The plurality of switches may be controlled so that the capacitor-and-inductor may be disconnected from the at least one capacitor and the output node at preset periods. Current resonating in the capacitor-and-inductor may increase during disconnection between the at least one capacitor and the output node. The plurality of switches may output the increased current to the battery by connecting the capacitor-and-inductor to the capacitor and the output node after the period, connect at least one capacitor and the output node in series after the period, and operate to reduce root mean square (RMS) current within the receiver.

Receiver of wireless power transmission system being switched to increase voltage of resonance circuit

There are provided an ohmic electrode, which includes a contact layer made of an Al alloy and formed on a nitride-based semiconductor layer functioning as a light emitting layer, a reflective layer made of Ag metal, formed on the contact layer and having some particles in-diffused to the semiconductor layer, and a protective layer formed on the reflective layer to restrain out-diffusion of the reflective layer; a method of forming the ohmic electrode; and a semiconductor light emitting element having the ohmic electrode. The present invention has strong adhesive strength and low contact resistance since the reflective layer and the light emitting layer directly form an ohmic contact due to the interface reaction during heat treatment, and the present invention has high light reflectance and excellent thermal stability since the contact layer and the protective layer restrain out-diffusion of the reflective layer during heat treatment.

Multi-layer ohmic electrode, semiconductor light emitting element having multi-layer ohmic electrode, and method of forming same

Provided are a method and apparatus for partially encrypting speech packets, more specifically, a method and apparatus for selecting partial encryption sets used for a partial encryption technique in which compressed speech packets are partially encrypted to obtain the same effect as a full encryption technique. The method includes the steps of: (a) compressing respective speech files stored in a large-capacity speech database into the speech packets using a speech codec; (b) measuring single-bit loss distortion and sequential-bit loss distortion of the speech packets compressed in step (a); (c) generating standards for selecting partial encryption sets based on the measurement results of the single-bit loss distortion and sequential-bit loss distortion; (d) selecting the partial encryption sets according to the generated standards; and (e) encrypting the speech packets using the selected partial encryption sets. In this method, distortion sensitivity caused by loss of a speech packet can be exactly measured in various embodiments so that partial encryption sets can be efficiently and securely selected based on the measurement result. As a result, by reducing the amount of encryption operation, encryption services can be applied in various wireless communication environments.

Method and apparatus for partially encrypting speech packets

The present invention relates to a pharmaceutical composition and health food comprisingsp. PL3 extract or phellinsin A isolated from the same as an effective component. More particularly, the present invention relates to a pharmaceutical composition and health food comprisingsp. PL3 extract or phellinsin A isolated from the same as an effective component, wherein thesp. PL3 extract and its phellinsin A inhibit the oxidation of low density lipoprotein (LDL), and further, they can be used as a component for medicine and food to effectively prevent and treat cardiovascular diseases such as hyperlipemia and arteriosclerosis.

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Daejeon, South Korea

Sang Han Lee