The invention relates to a device for electrically conductive connecting, by means of ultrasonic welding, of first electric conductors (140, 142) and second electric conductors (144, 146) in a compression space the cross section of which can be changed and which comprises at least one lateral slide, a sonotrode and a counter electrode, wherein firstly, blank ends of the first electric conductors (140, 142) are introduced into the compression space and are welded by means of ultrasonic action to form a first connection (148) and then after the first connection has been removed from the compression space, blank ends of the second electric conductors (144, 146) are introduced into same and are welded by means of ultrasonic action to form a second connection, wherein the first connection is fed to a retaining device (182, 184) before the second connection is welded.