Abstract: The present invention provides an electrically driven oxygen separation assembly and method of applying an electrical potential thereto in which one or more tubular membrane elements are provided having an anode layer, a cathode layer, an electrolyte layer and two current collector layers adjacent to and in contact with the anode layer and the cathode layer and situated on the inside and outside of the at least one tubular membrane element. The potential is applied to one of the two current collector layers at two central spaced locations of the at least one tubular membrane element and to the other of the two current collector layers at least at opposite end locations thereof. As a result the electric current flow through the tubular membrane element is divided into two parts flowing between the two central spaced locations and the opposite end locations.