Patent ID: 6669826
Filing Date: 2003-12-30
Classification: C25B,H01M,Y02E

Abstract:
An electrochemical cell stack comprising:(a) a first sub-stack, said first sub-stack comprising a plurality of proton exchange membrane (PEM) electrochemical cells arranged in series in a bipolar configuration; (b) a second sub-stack, said second sub-stack comprising a plurality of proton exchange membrane (PEM) electrochemical cells arranged in series in a bipolar configuration; (c) a top end plate; (d) a bottom end plate; (e) a first intermediate support, said first sub-stack being stacked,between said top end plate and said first intermediate support, said second sub-stack being stacked between said first intermediate support and said bottom end plate; (f) wherein said top end plate, said first intermediate support and said bottom end plate all extend beyond the peripheries of said first and second sub-stacks; (g) a first tie rod, said first tie rod being coupled to said top end plate and extending downwardly from said top end plate through said first intermediate support at a point peripheral to both of said first and second sub-stacks, said first tie rod terminating prior to said bottom end plate; and (h) first biasing means, mounted on said first tie rod below said first intermediate support and above said bottom end plate, for biasing said first intermediate support towards said top end plate.