Secondary battery comprising insulator
View Patent ↗Disclosed is a secondary battery having a structure in which a jelly-roll having a cathode/separator/anode structure is mounted in a cylindrical battery case, wherein a plate-shaped insulator mounted on top of the jelly-roll includes a perforated inlet enabling gas discharge and penetration of electrode terminals, a plurality of fine pores having a size that allows permeation of an electrolyte solution, but does not allow permeation of foreign materials, and a plurality of strip or bead shaped protrusions disposed in transverse and/or longitudinal directions on one or both surfaces of the insulator.
1. A secondary battery comprising:
a jelly-roll having a cathode, an anode, and a separator disposed between the cathode and the anode structure in a cylindrical battery case;
a plate-shaped insulator mounted on the top of the jelly-roll, the insulator including:
a perforated inlet enabling gas discharge and penetration of electrode terminals; and
a plurality of fine pores having a size of 1 μm to 100 μm;
wherein the insulator comprises a non-woven fabric in which fibers made of a polymer resin or composite form fine pores,
wherein the fibers are partially bonded through needle punching or thermal fusion, or using an adhesive agent to form a non-woven fabric,
wherein the non-woven fabric is made of fibers, parts bonded by thermal fusion are disposed by a predetermined distance over the entire surface of the insulator, and protrusions that are not thermally fused are disposed between the bonded parts,
wherein the protrusions are disposed on one or both surfaces of the insulator,
wherein the fine pores are dispersed by a predetermined distance over the entire surface of the insulator,
wherein the protrusions extend in transverse and longitudinal directions and cross each other to form a checker pattern, and
wherein the protrusions have a same height.
2. The secondary battery according to claim 1 , wherein the insulator is composed of an electrical-insulating polymer resin or an electrical-insulating polymer composite.
3. The secondary battery according to claim 2 , wherein the polymer resin is one or more selected from the group consisting of polyethylene, polypropylene, polybutylene, polystyrene, polyethylene terephthalate, natural rubbers and synthetic rubbers.
4. The secondary battery according to claim 1 , wherein the protrusions form an embossing pattern over the entire surface of the insulator.
5. The secondary battery according to claim 1 , wherein the insulator has a thickness of 0.1 mm to 0.5 mm.
6. The secondary battery according to claim 1 , wherein the battery is a lithium secondary battery.
7. A device comprising the secondary battery according to claim 1 as a power source.
8. The device according to claim 7 , wherein the device is selected from a cellular phone, a portable computer, an electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle and a device for power storage.
9. The secondary battery according to claim 1 , wherein the insulator divides the cylindrical battery case into an upper chamber and a lower chamber,
wherein the fine pores extend from the upper surface of the insulator to a lower surface of the insulator, and
wherein the upper surface of the insulator forms a lower surface of the upper chamber.
10. The secondary battery according to claim 1 , wherein the insulator is a single layer.
11. The secondary battery according to claim 1 , wherein the insulator divides the cylindrical battery case into an upper chamber and a lower chamber,
wherein the insulator has a top surface exposed to the upper chamber and a bottom surface exposed to the lower chamber, and
wherein the fine pores extend between the top surface and the bottom surface.