Patent ID: 8679672
Filing Date: 2014-03-25
Classification: B29C,H01M,Y02E

Abstract:
1. A flat battery shaped in a coin extending in a radial direction, comprising: an exterior can having a cylinder with a bottom, the cylinder having a sidewall, and an opening edge provided on one end of the cylinder, the bottom provided on the other end of the cylinder; a seal can having a space formed therein, the seal can comprising: a gasket molded between the second cylinder portion and the sidewall, the gasket extending inside the seal can around the opening edge portion extended to the flat portion, wherein the gasket has an inner surface exposing to the space, wherein the inner surface has a first angle and a second angle below the first angle, wherein the first angle is convex to the space, and the second angle is concave to the space, wherein both of the first angle and the second angle are located between a first portion and a second portion, the first portion corresponding to a part of the inner surface at the same level in the radial direction of the stepped portion, the second portion corresponding to a part of the inner surface at the same level in the radial direction of the opening edge portion, wherein the thickness of the gasket between the opening edge portion and the second portion is smaller than the thickness of the gasket in the radial direction between the second cylinder portion and the second portion.