The invention relates to a device for holding power storage assemblies (3), arranged side by side in a power storage module, in position, the device including: a plate (1) made of an electrically insulating material and extending along a main plane (P); recesses (2) provided in the plate, wherein each recess is to receive a respective power storage assembly such that the longitudinal axis of the storage assembly extends perpendicular to the main plane (P); and at least one holder made of an insulating material and intended for receiving an electrical connection means for electrically connecting at least one power storage assembly to an electronic board of the module.