Energy transmission device (6) for contactless transmission of electrical energy, comprising a primary coil device (7) and a secondary coil device (8) rotatably mounted about an axis of rotation (4) with respect to the primary coil device (7), wherein the primary coil device (7) has a primary yoke element (9), several primary leg elements (10, 11) and a primary winding (12) and the secondary coil device (8) has a secondary yoke element (13), several secondary leg elements (14, 15) and a secondary winding (16), wherein the primary yoke element (9) and / or the secondary yoke element (13) each consist of a laminated core, and wherein - viewed in longitudinal section with respect to the axis of rotation (4) - the primary yoke element (9) bears against at least one of the primary leg elements (10, 11) and / or the secondary yoke element (13) against at least one of the secondary leg elements (14, 15) along a butt edge (22, 23, 26, 27), where the butt edge (22,23,26,27) and / or its longitudinal center axis (24, 25, 28, 29) is inclined with respect to the axis of rotation (4), characterized in that - viewed in longitudinal section - the butt edge (22, 23, 26, 27) is stepped, and that the primary leg elements (10, 11) and / or the secondary leg elements (14, 15) each consist of a laminated core and have several laminated core parts (30) with a radially extending radial slot, wherein the laminated core parts (30) are arranged one another such that the radial slots of the several laminated core parts (30) are arranged circumferentially offset from one another.