The invention relates to a device for the heating a functional layer of coating material, such as a surface coating or an edge strip, in particular for applying the coating material onto an area of a workpiece, comprising a microwave source, an applicator and a microwave channel for supplying the microwave radiation generated in the microwave source to the applicator, wherein a microwave field is generable in the applicator on account of the supplied microwave radiation, wherein the applicator has at least one material channel, which passes through the applicator and through which the coating material can be fed such that the functional layer of the coating material is heated in the microwave field within the applicator.

A drying apparatus for secondary battery, wherein the drying apparatus dries an electrode sheet including an electrode current collector, a coated portion on which an electrode active material is applied on at least one surface of the electrode current collector, and a non-coated portion on which the electrode active material is not applied, wherein the coated portion is disposed to be parallel to a first direction to form at least one electrode line, includes an induction heating unit disposed to face the electrode sheet and drying the coated portion through electromagnetic induction, wherein the induction heating unit includes a multi-coil portion including a plurality of coils having different heating frequencies; and a switch portion provided to selectively apply current to any one of the plurality of coils.