RECTANGULAR SECONDARY BATTERY

To provide a highly reliable rectangular secondary battery. A rectangular secondary battery () includes: an electrode body () that includes a positive electrode plate and a negative electrode plate; a rectangular casing () that includes an opening and that contains the electrode body (); and a sealing plate () that seals the opening of the rectangular casing (). The sealing plate () includes a gas discharge valve () that ruptures when the pressure inside the rectangular casing () has a predetermined value or more to discharge gas inside the rectangular casing () to outside the rectangular casing (). A portion of a second negative electrode current collector () is disposed, as a shielding member, at a location that is between the sealing plate () and the electrode body () and that faces the gas discharge valve ().