Patent attributes
Disclosed is a coin battery including: positive and negative electrodes, a separator interposed therebetween, and an electrolyte; and a housing accommodating these elements. The housing includes: a cylindrical battery case having a bottom, and a first side wall rising from the periphery thereof; a sealing plate having a top, and a second side wall extending from the periphery of the top and along inside the first side wall; and a gasket between the first and second side walls. The sealing plate has: a first curved portion at the boundary between the top and the second side wall, a second curved portion continued from the first curved portion, a third curved portion continued from the second curved portion, and a descending portion continued from the third curved portion. The ratio: R1/R2 where R1 and R2 are outer radii of curvatures of the first and second curved portions is 0.22 to 1.88.
