Abstract: The present invention provides a composite cathode active material, which comprises a core layer comprising a cathode active material; a hydrogen fluoride barrier layer coating the core layer, the hydrogen fluoride barrier layer comprising a substance consisting of any one of Nb, Ba, Zr, Mn, Mg, Al and Ca or any combination thereof and any one of O, F, B and P or any combination thereof; and a physical barrier layer coating the hydrogen fluoride barrier layer. By using the composite cathode active material, preparation method thereof, cathode sheet and lithium ion secondary battery of the present invention, the contacting and reacting of the hydrogen fluoride with cathode active material are effectively prevented, the dissolution of the metal in the cathode active material is inhibited, the stability of the crystal structure in the bulk phase of the cathode active material is ensured, and the increase of the cycle retention rate and the decrease of the impedance growth rate are realized.

Abstract: The present invention discloses a micro-capsule type silicon-carbon composite negative electrode material, and the negative electrode material comprises a current collector and a silicon-carbon coating layer formed by drying silicon-carbon paste coating the current collector; the silicon-carbon slurry comprises a carbonaceous paste and silicon capsule powder dispersed in the carbonaceous paste; the carbonaceous paste comprises a dispersing agent, and a carbon material, a first conductive agent and a first binder dispersed in the dispersing agent; the silicon capsule powder has micro-capsule structures comprising silicon powder and a second binder coating the surface of the silicon powder and in which the silicon powder is a core and the second binder is an outer shell; and the first binder is different from the second binder. The improved silicon-carbon composite negative electrode material of the present disclosure has excellent effects in cycle performance, coulombic efficiency and rate capability.

Abstract: Systems, methods, and apparatus for meta-materials which are stretchable and tunable using an array of liquid conductor meta-atoms encased in one or more layers of elastomer. Fabrication techniques allow effective manufacture of the metamaterial in a number of form factors for a number of applications, including but not limited to fabrics or wraps around three-dimensional shapes.

Abstract: The present invention discloses a micro-capsule type silicon-carbon composite negative electrode material, and the negative electrode material comprises a current collector and a silicon-carbon coating layer formed by drying silicon-carbon paste coating the current collector; the silicon-carbon slurry comprises a carbonaceous paste and silicon capsule powder dispersed in the carbonaceous paste; the carbonaceous paste comprises a dispersing agent, and a carbon material, a first conductive agent and a first binder dispersed in the dispersing agent; the silicon capsule powder has micro-capsule structures comprising silicon powder and a second binder coating the surface of the silicon powder and in which the silicon powder is a core and the second binder is an outer shell; and the first binder is different from the second binder. The improved silicon-carbon composite negative electrode material of the present disclosure has excellent effects in cycle performance, coulombic efficiency and rate capability.