Abstract: A button-type secondary battery includes a lower can having a bottom surface; an upper can having a top, the upper can and the lower can being coupled to define a space therein; an electrolyte in the space; an electrode assembly in the space and including a negative electrode, a separator, and a positive electrode wound together; a gasket between the upper can and the lower can to electrically insulate the upper and lower cans; a top insulator that is electrically insulating and covering a top surface of the electrode assembly; and a bottom insulator that is electrically insulating and covering a bottom surface of the electrode assembly. The top and bottom insulators are each configured to expand in volume by absorbing the electrolyte. Surfaces of at least one of the top insulator and the bottom insulator are coated with a protective layer to prevent thermal shrinkage from occurring.

Abstract: A button type secondary battery includes a wound electrode assembly; a lower can with the electrode assembly and an electrolyte in the lower can; a top plate to close the lower can; a positive electrode terminal coupled to the top plate through a gasket to be electrically insulated from the top plate with a portion of the positive electrode terminal passing through a hole in the top plate to be bonded to a positive electrode tab; a top insulator covering a top surface of the electrode assembly; and a bottom insulator covering a bottom surface of the electrode assembly. The top insulator and the bottom insulator are each configured to expand in volume by absorbing the electrolyte. Surfaces of at least one or more of the top insulator and the bottom insulator are coated with a protective layer configured to prevent thermal shrinkage from occurring.

Abstract: Discloses is an unpowered transparent antenna that can be installed to reduce or remove a radio wave shadow area such as an interior even without power. In order to achieve the objectives, an unpowered transparent antenna includes: a first conductive layer having a mesh structure; and a second conductive layer having a mesh structure and positioned on the bottom of the first conductive layer, in which an aperture ratio of the first and second conductive layers is 50% or more.

Abstract: An installation structure of a ground rod for driving the rod deep into the ground comprising an overhead earth wire installed to protect transformers, power-transmission lines, etc. from lightning; a ground wire that is extended from a lightning arrester to a ground; a multi-stage ground rod elongated by a thread type connection and connected with the end of the ground wire that it is buried into the ground; and a connecting sleeve for connecting the ground rod to the ground wire, the electric conductive compound preventing corrosion in the thread connection including a lead terminal side junction of the and a ground wire side junction of the connecting sleeve. Corrosion of the gap between junctions is inhibited by inserting electric conductive compound into the junctions of the lead terminal side and of the ground wire side of the ground wire connecting sleeve, increasing ground rod lifetimes and decreasing maintenance costs.

Abstract: An installation structure of a ground rod for driving the rod deep into the ground comprising an overhead earth wire installed to protect transformers, power-transmission lines, etc. from lightning; a ground wire that is extended from a lightning arrester to a ground; a multi-stage ground rod elongated by a thread type connection and connected with the end of the ground wire that it is buried into the ground; and a connecting sleeve for connecting the ground rod to the ground wire, the electric conductive compound preventing corrosion in the thread connection including a lead terminal side junction of the and a ground wire side junction of the connecting sleeve. Corrosion of the gap between junctions is inhibited by inserting electric conductive compound into the junctions of the lead terminal side and of the ground wire side of the ground wire connecting sleeve, increasing ground rod lifetimes and decreasing maintenance costs.