Lock, locking mechanism, battery pack and vehicle

The invention discloses a lockset, a locking mechanism, a battery pack and a vehicle, and belongs to the technical field of new energy automobiles, and the lockset comprises a lock shell, a lock cylinder and a lock bead. The lock shell comprises an upper lock shell body and a lower lock shell body which are connected with each other, a lock shell containing cavity is defined by the upper lock shell body and the lower lock shell body, and a lock bead window communicated with the lock shell containing cavity is formed in the side wall of the upper lock shell body. The lock cylinder is located in the lock shell containing cavity and movably connected with the lower lock shell. The lock bead is clamped between the lock cylinder and the inner wall of the upper lock shell, the lock cylinder can move in the lock shell containing cavity and enables the lock bead to stretch out or retract relative to the lock bead window, the lower lock shell is configured to be installed on a battery pack body of a battery pack, and