FRAMELESS ELECTROCHEMICAL CELL STACK HAVING SELF CENTERING RIGID PLASTIC BUSHINGS IN ALIGNED THROUGH HOLES OF INTERCONNECTS AND MEMBRANE ASSEMBLIES

摘要

A frameless multi-cell electrochemical stack, filter-press sealed between two end headers, comprising an alternate succession of planar, electrically conductive inter-cell interconnects and membrane assemblies having aligned through holes along perimeter portions for composing inlet and outlet manifolds (4-3; 3-4,...) of parallel flow or ziz-zag flow paths of serial flow, respectively, for circulating distinct electrolyte solutions in respective flow compartments of all the cells, separated by the permionic membrane (M) of a membrane assembly sandwiched between two electrically conductive inter-cell interconnects (I), the perimeter portion of the membrane (M) being held between rear planar surfaces of two elastomeric gaskets (G1, G2) assembled back-to-back and similarly bas-relief patterned over their front surfaces for defining separate flow paths (6) of the electrolyte solutions in respective flow compartments coinciding with a central window of one and of the other of said two bas-relief patterned gaskets, has simple rigid plastic bushings (13, B) in the through holes of the planar electrically conductive inter-cell interconnects (I) and in the aligned through holes (4-3, 3-4), of the two back-to-back assembled, bas-relief patterned elastomeric gaskets of each membrane assembly for cooperatively providing a self-aligning function (13g+Cr1) and for implementing an O-ring type seal function (Or+Cr2) that enhances the hydraulic seals of the back-to-back assembled gaskets within the aligned through holes (4-3, 3-4,...) thereof. Optionally, counter-opposed comb like strip inserts (8s) of rigid plastic along inlet and outlet sides of the cell compartments improve the hydraulic seal on the permionic membrane sandwiched between the back-to-back assembled gaskets.