LOCKING METHOD AND UNLOCKING METHOD

A locking method and an unlocking method are provided. The locking method is used to mount a battery to a fixing seat of an electric vehicle by a locking device. The locking device includes: a lock base (20) including a lock body (25), a surface of the lock body (25) being provided with a lock groove (21) recessed towards the interior of the lock body (25), the lock body (25) being internally provided with a lock tongue groove (22) and a lock tongue (24) movably mounted in the lock tongue groove (22), and the lock tongue groove (22) being in communication with the lock groove (21); and a lock shaft (30) including a shaft rod (31) configured to be inserted into the lock groove (21) of the lock base (20) to perform unlocking and locking.