One aspect is a process for producing a segmented electrode, including providing a pipe made of metal having an outer side and an inner side, wherein the inner side of the pipe forms a hollow space. A support structure is arranged in the hollow space, so that the support structure mechanically stabilizes the pipe. Intermediate spaces are formed in the pipe, which define a plurality of segments in the pipe. An electrically insulating material is introduced into the intermediate spaces and thus forming electrically insulating areas, wherein a boundary layer is in each case defined between the segments and the areas. The pipe is cut so that several segmented ring-shaped electrodes are formed therefrom. The support structure is removed from the pipe.