Internal electrolyte supply system for reliable transport throughout fuel cell stacks

In a fuel cell stack having electrolyte feed and drain means and a plurality of stacked fuel cells, each fuel cell including bipolar plates separating said fuel cell from adjacent fuel cells in said stack thereof and an electrolyte-containing matrix disposed between said plates, an improved internal electrolyte supply system interconnecting said feed and drain means, comprising:

• (a) first means defined repeatedly throughout said fuel cell stack for flowing electrolyte along a series of first paths each extending directly through one of said cells in said stack between said plates thereof so as to expose electrolyte to said matrix of said cell;
• (b) second means defined repeatedly throughout said fuel cell stack for flowing electrolyte along a series of second paths extending through said plates of said cell stack at opposite ends of said first paths, said second paths being in communicative flow relation to the first paths and adapted to supply electrolyte directly to the respective first paths;
• and
• (c) an electrolyte transport wick disposed along each of the first paths through the cells and engaged with the matrix of the respective cell for facilitating transfer of electrolyte thereto.

In a fuel cell stack having electrolyte feed and drain means and a plurality of stacked fuel cells, each fuel cell including bipolar plates separating said fuel cell from adjacent fuel cells in said stack thereof and an electrolyte-containing matrix disposed between said plates, an improved internal electrolyte supply system interconnecting said feed and drain means, comprising:

• (a) first means defined repeatedly throughout the said fuel cell stack for flowing electrolyte along a series of first paths each extending directly through one of said cells in said stack between said plates thereof so as to expose electrolyte to said matrix of said cell;
• (b) second means defined repeatedly throughout said fuel cell stack for flowing electrolyte along a series of second paths extending through said plates of said cell stack at opposite ends of said first paths, said second paths being in communicative flow relation to said first paths and adapted to supply electrolyte directly to said respective first paths;
• and
• (c) third means defined in said plates between said first and second means which establish said communicative flow relation and produce a cascading electrolyte flow therebetween.

In a fuel cell stack having electrolyte feed and drain means and a plurality of stacked fuel cells, each fuel cell including bipolar plates separating said fuel cell from adjacent fuel cells in said stack thereof and an electrolyte-containing matrix disposed between said plates, an improved internal electrolyte supply system interconnecting said feed and drain means, comprising:

• (a) first means defined repeatedly throughout said fuel cell stack for flowing electrolyte along a series of first paths each extending directly through one of said cells in said stack between said plates thereof so as to expose electrolyte to said matrix of said cell;
• (b) second means defined repeatedly throughout said fuel cell stack for flowing electrolyte along a series of second paths extending through said plates of said cell stack at opposite ends of said first paths, said second paths being in communicative flow relation to said first paths and adapted to supply electrolyte directly to said respective first paths;
• and
• (c) third means disposed at said opposite ends of each of said first paths and extending into said second paths for diverting electrolyte from said second paths to said first paths.