Abstract: Disclosed is a battery pack fixing system. The battery pack fixing system comprises a locking mechanism (1), wherein the locking mechanism (1) is arranged on the contact surface of a battery pack (2) and a support (3), and the battery pack (2) is unlocked or locked on the support (3) by rotating the locking mechanism (1). According to the battery pack fixing system, the battery pack (2) is unlocked or locked on the support (3) by using the rotation movement of the locking mechanism (1) in different directions, so that the objective of fixing the battery pack (2) on the support (3) is achieved; and compared with a traditional locking mechanism, the battery pack fixing system has advantages such as being firmer in fixing and highly reliable. Further disclosed are a mounting method and a dismounting method for the battery pack.

Abstract: Provided are a battery holder, a power transfer device, an electric vehicle and an installation method for electric vehicle. The battery holder includes a fixing bracket, a lock mechanism and a plurality of supporting devices, the lock mechanism is fixed on the fixing bracket, the supporting device is fixed on one side of the fixing bracket facing the battery pack. The electric vehicle includes the battery holder as described above. In the present invention, the weight of the battery pack can be simultaneously distributed on the plurality of supporting devices and the lock mechanism, the force of the fixing bracket is more evenly, the force applied by the battery pack to the lock mechanism is reduced, the force concentration of the lock mechanism on the fixing bracket is prevented, the service life of lock mechanism is improved, and improve the connection strength between battery pack assembly and battery holder.

Abstract: Provided is a lock mechanism, wherein the lock mechanism includes a lock base, the lock base is provided with an opening and a cavity extending from the opening, the opening is used for the lock shaft mounted to the battery pack to enter the cavity, the lock mechanism further includes: a lock assembly, the lock assembly is connected to one side of the lock base opposite the lock shaft, the lock assembly is moveable relative to the lock base, and the side of the lock base opposite the lock shaft extends into the cavity or exits the cavity; wherein, the lock assembly is capable of preventing the lock shaft from exiting the cavity from the opening when the lock assembly extends into the cavity; the lock assembly is capable of allowing the lock shaft to exit the cavity from the opening when the lock assembly exits the cavity.

Abstract: Provided is a lock mechanism, wherein the lock mechanism includes a lock base, the lock base is provided with an opening and a cavity extending from the opening, the opening is used for the lock shaft mounted to the battery pack to enter the cavity, the lock mechanism further includes: a lock assembly, the lock assembly is connected to one side of the lock base opposite the lock shaft, the lock assembly is moveable relative to the lock base, and the side of the lock base opposite the lock shaft extends into the cavity or exits the cavity; wherein, the lock assembly is capable of preventing the lock shaft from exiting the cavity from the opening when the lock assembly extends into the cavity; the lock assembly is capable of allowing the lock shaft to exit the cavity from the opening when the lock assembly exits the cavity.

Abstract: Provided is a lock mechanism, wherein the lock mechanism includes a lock base, the lock base is provided with an opening and a cavity extending from the opening, the opening is used for the lock shaft mounted to the battery pack to enter the cavity, the lock mechanism further includes: a lock assembly, the lock assembly is connected to one side of the lock base opposite the lock shaft, the lock assembly is moveable relative to the lock base, and the side of the lock base opposite the lock shaft extends into the cavity or exits the cavity; wherein, the lock assembly is capable of preventing the lock shaft from exiting the cavity from the opening when the lock assembly extends into the cavity; the lock assembly is capable of allowing the lock shaft to exit the cavity from the opening when the lock assembly exits the cavity.

Abstract: Provided are a battery holder, a power transfer device, an electric vehicle and an installation method for electric vehicle. The battery holder includes a fixing bracket, a lock mechanism and a plurality of supporting devices, the lock mechanism is fixed on the fixing bracket, the supporting device is fixed on one side of the fixing bracket facing the battery pack. The electric vehicle includes the battery holder as described above. In the present invention, the weight of the battery pack can be simultaneously distributed on the plurality of supporting devices and the lock mechanism, the force of the fixing bracket is more evenly, the force applied by the battery pack to the lock mechanism is reduced, the force concentration of the lock mechanism on the fixing bracket is prevented, the service life of lock mechanism is improved, and improve the connection strength between battery pack assembly and battery holder.

Abstract: Provided is a lock mechanism, wherein the lock mechanism includes a lock base, the lock base is provided with an opening and a cavity extending from the opening, the opening is used for the lock shaft mounted to the battery pack to enter the cavity, the lock mechanism further includes: a lock assembly, the lock assembly is connected to one side of the lock base opposite the lock shaft, the lock assembly is moveable relative to the lock base, and the side of the lock base opposite the lock shaft extends into the cavity or exits the cavity; wherein, the lock assembly is capable of preventing the lock shaft from exiting the cavity from the opening when the lock assembly extends into the cavity; the lock assembly is capable of allowing the lock shaft to exit the cavity from the opening when the lock assembly exits the cavity.