Abstract: A battery pack for the propulsion of electric road, boat or aircraft vehicles, includes a plurality of battery modules. The battery cells of the pack are arranged with their planes oriented horizontally, according to a “lasagna” configuration, over a lower tray. Superimposed layers of cells are provided, separated by aluminum sheets, which hinder the propagation of heat and flame. Between the cells there are tubes of a circuit for a coolant or alternatively a cooling panel is provided under the cell layers. The cells have one side glued to an adjacent aluminum sheet and the opposite side also glued to an adjacent aluminum sheet or covered by a pad of elastically deformable material. The terminals of some cells side-by-side are connected to each other by means of bars held in position by clamps, with an arrangement such as to simplify the assembly procedure.