A single cell having a casing formed from a first casing side part, a second casing side part and a casing frame, in which casing an electrolyte and an electrochemically active electrode foil unit are arranged, wherein the casing comprises an overpressure protection. The first casing side part includes a casing side part segment going at least sectionally over a length of the single cell, which casing side part segment is angled down in relation to the first casing side part in the direction of the cell interior and in which the overpressure protection is arranged and a venting opening is incorporated into the casing frame in a region of the overpressure protection.