The present invention relates to a device for the contact-free inductive transfer of electrical energy from a first, preferably stationary system of a shifting device into a second system of the shifting device, which can be moved relative to the first system, comprising a magnetic circuit of a primary core, which is assigned to the first system and onto which a primary coil is wound, and a secondary core, which is assigned to the second system and onto which a secondary coil is wound. The secondary core is arranged so as to be capable of being shifted relative to the primary core along a shifting path, which preferably runs parallel to a shifting path of the shifting device. The primary core extends at least along the entire length of the shifting path. According to the invention, provision is made for the primary core to comprise at least one primary core gap, which is embodied along the entire longitudinal extension of the primary core. The invention further relates to a shifting device, in particular a linear shifting device, comprising such an energy transfer device as well as to a method for operating such a device.