Samsung Sdi Co., Inc.

Sangbong Nam

Jinwook Kim

Yongtae Kim

Yooeup Hyung

Seok-Gyun Chang

Jungseog Kim

Kyonghwan Song

Soonki Woo

Hyoungsu Kim

Seokgyun Chang

Jungseok Kim

Jongku Kim

Youngtaek Kim

Younhan Chang

In a cylindrical lithium ion secondary battery, the width of an electrode tab positioned at a center of an electrode assembly is extended so that it serves as a center pin and functions to release heat. Thus, it is not necessary to separately insert a center pin, thereby reducing the manufacturing cost and steps. The cylindrical lithium ion secondary battery comprises an electrode assembly, a case for receiving the electrode assembly, and a cap assembly for sealing the top opening of the case. The electrode assembly comprises a positive electrode plate and negative electrode plate. The positive electrode plate has a positive electrode tab, a positive active material region, a positive uncoated region, and a positive current collector exposed through the positive uncoated region. The negative electrode plate has a negative electrode tab, a negative active material region, a negative uncoated region, a negative current collector exposed through the negative uncoated region, and a separator interposed between the positive and negative electrode plates. At least one of the positive and negative electrode tabs has an extended width at the center of the electrode assembly.

Cylindrical lithium ion secondary battery

A lithium secondary battery has protrusions or depressions formed on a surface of a gasket, which makes contact with a safety vent, so that gas, which is generated inside the battery, and an electrolyte, do not leak, thereby improving the safety.

Lithium secondary battery

A cylindrical lithium ion secondary battery includes a center pin fabricated with an inexpensive material and having a coating layer formed on the outer surface of the center pin. The cylindrical lithium ion secondary battery includes an electrode assembly having the center pin inserted through the center of the electrode. A case is provided for housing the electrode assembly and an electrolyte. A cap assembly seals the case. The center pin includes a body formed from a metallic material and a coating layer is formed on the outer surface of the body.

Electrode assemblies easily impregnated with an electrolyte are provided. A sealing tape attached to the outer circumference of the electrode assembly comprises a material having an affinity for the electrolyte. Alternatively, the entire sealing tape or a portion of the tape is coated with the material. In another alternative, the surface of the sealing tape is rough, thereby improving wetting of the tape by the electrolyte and diffusion of the electrolyte into the tape. In another embodiment, first and second insulating plates comprise a material having an affinity for the electrolyte. In another alternative, the insulating plates comprise a mixture of a material having an affinity for the electrolyte and polypropylene or polyethylene. Alternatively, the surfaces of the insulating plates are coated with the material or with a surfactant that reduces the surface tension of the electrolyte.

Lithium ion secondary battery

Growing community of inventors

Yongin-si, South Korea

Sangbong Nam