Single cell battery, battery module, power battery, and electric vehicle

Abstract

The present disclosure is directed to a single-cell battery, a battery module, a power battery, and an electric vehicle. The single-cell battery includes a case, a battery cell, an electrode terminal, and a cover plate. The electrode terminal includes a battery post. The single-cell battery further includes a current interruption device mounted on the battery post. The current interruption device has a conductive member and a flipping member connected to the conductive member for mutual electrical connection. The flipping member and the conductive member can be electrically disconnected from each other under action of air pressure. The conductive member is connected to the battery post for mutual electrical connection. The flipping member and the conductive member are connected to each other by using a boss welded structure. The boss welded structure includes a boss, a connection hole accommodating the boss, and an annular welding spot located between the boss and the connection hole. The flipping member includes the connection hole. The conductive member includes the boss. The conductive member is connected to an outer end surface of the battery post. An outer periphery of the flipping member is fixed relative to the cover plate. The battery post is mounted in a ceramic ring connected to the cover plate and is insulated from the outer periphery of the flipping member by using the ceramic ring.