US Patent 7709147 Storage battery and production method thereof

A storage battery includes: a bottomed metal case (10) accommodating an electrolyte and a collector (7) having a flat plate connected to one side of an electrode assembly (5) containing a strip-shaped positive electrode plate (1), a strip-shaped negative electrode plate (2), and a separator (6); a sealing plate (11) sealing upside of the bottomed metal case; and a lead terminal (9) electrically connecting the sealing plate to the collector, wherein the collector has at least one projection (13) and the collector and the lead terminal are electrically connected with each other via the projection. This construction eliminates the problem of increased contact resistance between the lead terminal and the collector and realizes a storage battery having high current discharging performance in which the contact resistance is reduced.