Abstract: A safety opening/closing valve for easy checking of an opened/closed state thereof includes: a ball valve part having a rotating shaft part configured to open and close a flow path of the ball valve part by rotating; a housing part having an upper surface and having a plurality of gear teeth vertically formed along the inner circumference of an inner space of the housing part; a rotating part arranged in the housing part such that the rotating part rotates relative to the central axis of the housing part; at least three satellite gear parts mounted rotatably to the upper portion of the rotating part while being in engagement with gear teeth formed at the inner circumference of the housing part; a driving part including a sun gear part provided as a bar shape and inserted through an open central area of a top surface of the housing part.

Abstract: A negative electrode active material and a method for preparing a negative electrode active material, comprising preparing a silicon-based compound including SiOx, wherein 0.5<x<1.3, and forming a crystalline carbon coating layer on the silicon-based compound through a chemical vapor deposition method using an organometallic compound as a source, wherein the organometallic compound is at least any one selected from the group consisting of aluminum acetylacetonate, aluminum ethoxide, aluminum phenoxide, aluminum acetate, aluminum tributoxide, and a combination thereof.

Abstract: The present invention relates to a negative electrode active material including silicon-based oxide particles and a metal distributed on a surface, inside, or on the surface of and the inside the silicon-based oxide particles, wherein compressive fracture strength measured at a pressure of 100 mN is 170 MPa to 380 MPa, and the silicon-based oxide particles contain Si crystal grains having a crystal grain size of 3 nm to 20 nm.

Abstract: A negative electrode active material including a core, an intermediate layer on a surface of the core, and a shell layer on a surface of the intermediate layer, wherein the core includes a silicon oxide of SiOx (0<x<2); the intermediate layer includes a lithium silicate, the shell layer includes lithium fluoride (LiF) and the intermediate layer is present in an amount of 5 wt %-15 wt % based on a total weight of the negative electrode active material. Also, a method for preparing the negative electrode active material, and a negative electrode and lithium secondary battery including the same. The negative electrode active material provides excellent initial efficiency and life characteristics.

Abstract: A negative electrode active material which includes a secondary particle including first primary particles, wherein the first primary particle includes a core including SiOx, wherein 0?x<2, an intermediate layer which covers at least a portion of a surface of the core and includes silicon nitride, silicon oxynitride, or a mixture thereof, and a carbon coating layer which covers at least a portion of the intermediate layer and includes nitrogen-doped carbon, and a negative electrode and a lithium secondary battery which include the same.

Abstract: A negative electrode active material including a core, an intermediate layer on a surface of the core, and a shell layer on a surface of the intermediate layer, wherein the core includes a silicon oxide of SiOx (0<x<2); the intermediate layer includes a lithium silicate, the shell layer includes lithium fluoride (LiF) and the intermediate layer is present in an amount of 5 wt %-15 wt % based on a total weight of the negative electrode active material. Also, a method for preparing the negative electrode active material, and a negative electrode and lithium secondary battery including the same. The negative electrode active material provides excellent initial efficiency and life characteristics.

Abstract: The present invention relates to a silicon-based particle-polymer composite, which includes silicon-based particles; and a polymer coating layer formed on the silicon-based particles, in which the polymer coating layer includes metal-substituted poly(acrylic acid) in which hydrogen atoms in carboxyl groups of the poly(acrylic acid) chain are substituted with one or more selected from the group consisting of K, Na and Li.

Abstract: The present invention relates to a negative electrode active material which includes a secondary particle including a first particle which is a primary particle, wherein the first particle includes a first core and a first surface layer which is disposed on a surface of the first core and contains carbon, and the first core includes a metal compound which includes one or more of a metal oxide and a metal silicate and one or more of silicon and a silicon compound; a method of preparing the same; an electrode including the same; and a lithium secondary battery including the same.

Abstract: Composite particles and a negative electrode active material including such particles for an electrochemical device. The negative electrode active material is capable of lithium intercalation/deintercalation and includes composite particles including a carbon phase including a carbonaceous material, silicon (Si) and lithium fluoride (LiF). The Si and LiF may be present as Si—LiF mixed particles, which are dispersed in the carbon phase, wherein the Si—LiF mixed particles are dispersed in the carbon phase with uniform or non-uniform distribution. In addition, the composite particles include the carbon phase mixed uniformly or amorphously with the Si—LiF mixed particles.