Electrode stack for a charged particle beam generator for a lithography system, wherein the electrode stack comprises: - a plurality of stacked electrodes (71'-80') for manipulating a charged particle beam along an optical axis (A'), wherein each electrode comprises a flat, disk- or ring-shaped, electrode body provided with a flat top surface and a flat bottom surface, the bottom surface and top surface being connected to each other via a side surface defining an outer electrode perimeter, the electrode body being provided with an electrode aperture (82,82') for permitting passage of the charged particle beam, wherein the electrode bodies are mutually spaced along an axial direction (Z,Z') that is substantially parallel with the optical axis, and wherein the electrode apertures are coaxially aligned along the optical axis, and - spacing structures (89,89') essentially consisting of an electrically insulating material, each spacing structure (89, 89') having a height (Hs, Hd) defining a distance between respective neighboring electrodes (72, 73) in the electrode stack by being arranged in between each pair of adjacent electrodes for positioning the electrodes (71'-80') at predetermined mutual distances along the axial direction (Z,Z'); wherein a first electrode and a second electrode of said plurality (71'-80') each comprise an electrode body with one or more support portions (86,86'), wherein each support portion is configured to accommodate at least one spacing structure (89,89'), wherein the electrode stack is formed with at least one clamping member (91a',91b',91c') that is configured for holding together the respective support portions (86,86') of the first and second electrodes, with the at least one spacing structure (89,89') located in between, characterised in that at least one of the first and second electrodes (71'-80') comprises three support portions (86,86') along a radially outward perimeter of the electrode body, wherein the three support portions jointly support a weight of the electrode body, and wherein a support portion (86,86') is connected in a radially movable manner to the electrode body of the corresponding electrode (71 '-80') by means of an electrode support member. - a plurality of stacked electrodes (71'-80') for manipulating a charged particle beam along an optical axis (A'), wherein each electrode comprises a flat, disk- or ring-shaped, electrode body provided with a flat top surface and a flat bottom surface, the bottom surface and top surface being connected to each other via a side surface defining an outer electrode perimeter, the electrode body being provided with an electrode aperture (82,82') for permitting passage of the charged particle beam, wherein the electrode bodies are mutually spaced along an axial direction (Z,Z') that is substantially parallel with the optical axis, and wherein the electrode apertures are coaxially aligned along the optical axis, and - spacing structures (89,89') essentially consisting of an electrically insulating material, each spacing structure (89, 89') having a height (Hs, Hd) defining a distance between respective neighboring electrodes (72, 73) in the electrode stack by being arranged in between each pair of adjacent electrodes for positioning the electrodes (71'-80') at predetermined mutual distances along the axial direction (Z,Z'); wherein the electrode stack is formed with at least one clamping member (91a',91b',91c') that is configured for holding together the respective support portions (86,86') of the first and second electrodes, with the at least one spacing structure (89,89') located in between, characterised in that at least one of the first and second electrodes (71'-80') comprises three support portions (86,86') along a radially outward perimeter of the electrode body, wherein the three support portions jointly support a weight of the electrode body, and wherein a support portion (86,86') is connected in a radially movable manner to the electrode body of the corresponding electrode (71 '-80') by means of an electrode support member.