The present disclosure relates to a plug-in module connector or the electrically conductive connection of at least two battery modules, including a flexible busbar for the electrically conductive connection of respective poles of the battery modules, the busbar enabling tolerance compensation with respect to the poles in the transverse direction of the module connector; two retaining clamps for gripping the busbar and one of the respective poles of the battery modules, the retaining clamps enabling tolerance compensation with respect to the poles in the longitudinal direction and vertical direction of the module connector; an insulation housing in which the retaining clamps plugged onto the busbar can be received. Furthermore, the present disclosure also concerns a method for the electrically conductive connection of at least two battery modules by means of a plug-in module connector.