The present disclosure relates to an electric discharge device and associated method for molecular restructuring of a fluid. The electric discharge device comprises a discharge cell including a first dielectric layer and a second dielectric layer that are spaced apart by a gap constituting a flow channel for a feed fluid to be molecularly restructured. The dielectric layers and the flow channel are arranged between a first electrode and a second electrode for generating electric discharge in the flow channel when voltage is applied between the electrodes. The discharge cell comprises a double-walled dielectric tube having an inner wall and an outer wall that come together at both ends of the tube to form a double-walled dielectric tube made in one piece, the inner and outer walls of the double-walled dielectric tube constituting the first and second dielectric layers of the discharge cell.