NOVELTY - The system has tools (12), each including alignment elements (13, 14) to align the tool with respect to an object according to longitudinal and transverse axes (X, Y) of structure of vehicle. Support elements (15) support the tool against bottom (25) of the structure to allow trimming of the structure in a plane around the longitudinal and/or transverse axis. Locking and/or unlocking elements (16) actuate a fixing bolt (17) between a locking configuration to lock the object under the structure and an unlocking configuration to release the object with respect to the structure.    USE - Locking and/or unlocking system for use in an assembly and/or disassembly device (claimed) to lock and/or unlock an object i.e. power supply battery, of a drive motor of an electric or hybrid car, below a structure i.e. frame or body of the vehicle. Can also be used for locking and/or unlocking the power supply battery of drive motor of lorry, railway freight, boat, aircraft and cargo liner.    ADVANTAGE - The system enables locking and/or unlocking the object of the drive motor of the electric or hybrid car below the frame of the vehicle in a simple, reliable, robust, flexible, universal and economic manner. The system provides tools and battery exchange system in an economic manner, avoids a need to reinvest the tools with each evolution of design and/or position of fixation of battery and to limit risks of failures related to geometrical defects by the use of bolts. The system enables trimming the vehicle on the support of bolt independent of the vehicle.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for the following:    (1) a device for assembling and/or disassembling an object of drive motor of an electric or hybrid car below a structure    (2) a method for disassembling an object of drive motor of an electric or hybrid car below a structure    (3) a method for assembling an object of drive motor of an electric or hybrid car below a structure.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view illustrating disassembling a battery under a frame of a vehicle.    Longitudinal axis of structure (X)    Transverse axis (Y)    Tool (12)    Alignment elements (13, 14)    Support elements (15)    Locking or unlocking elements (16)    Fixing bolt (17)    Bottom of structure (25)