A passive-pumping liquid feed fuel cell system couplable to a cartridge module having a cartridge housing having an interior cavity and an exterior surface, a cartridge liquid fuel stream port encompassed by said housing exterior surface and having a sealable valve accommodating bidirectional flow of said liquid fuel stream into and out of said cartridge module, a bladder disposed within said interior cavity and capable of storing, delivering and receiving a quantity of said liquid fuel stream, a compression mechanism for imparting at least a minimal positive fluid pressure to said bladder, a pressure relief valve for discharging a gaseous stream from said cartridge housing at a set pressure;
- and a vacuum relief valve for drawing a gaseous stream into said interior cavity to inhibit formation of a vacuum within said cartridge housing, said system comprising:
- (a) a fuel delivery module couplable to said cartridge, comprising:
- (1) an inlet/outlet port for intermittently admitting and discharging said pressurized fuel stream to and from said fuel delivery module, respectively, said fuel delivery module inlet/outlet port capable of cooperating with said cartridge module inlet/outlet port to inhibit leakage of said intermittently admitted and discharged pressurized fuel stream;
- (2) a fuel delivery module outlet for discharging at least a portion of said pressurized fuel stream from said fuel delivery module;
- (3) a pressurized fuel stream conduit interconnecting said fuel delivery module inlet/outlet port and said fuel delivery module outlet, said pressurized fuel stream conduit having a flow regulating mechanism interposed therein for allowing flow in said pressurized fuel stream conduit when said flow regulating mechanism is in an open position and inhibiting flow in said pressurized fuel stream conduit when said flow regulating mechanism is in a closed position;
- (4) a recycle fuel stream conduit for directing a recycle fuel stream from a fuel delivery module recycle fuel stream inlet to said pressurized fuel stream conduit at a junction located between said fuel delivery module fuel stream port and said flow regulating mechanism, said recycle fuel stream conduit having a pressure-activated mechanism disposed therein for inducing flow between said recycle fuel stream inlet and said junction;
- (b) a fuel cell module comprising at least one electrochemical fuel cell comprising:
- (1) an anode fluidly connected to said fuel delivery module outlet, said anode promoting electrocatalytic conversion of at least a portion of said pressurized fuel stream to cations and an anode exhaust stream, said anode exhaust stream comprising un-reacted fuel stream constituents, if any, and anode reaction products;
- (2) a cathode for promoting electrocatalytic reaction of said cations with an oxidant stream directed to said cathode, said cathode electrically connected to said anode via a circuit comprising an electrical load, whereby electrons are drawn from said anode to said cathode via said circuit and a cathode exhaust stream is produced;
- (3) a cation exchange membrane interposed between said anode and said cathode;
- (c) an exhaust module comprising:
- (1) an exhaust module inlet for receiving said anode exhaust stream;
- (2) an exhaust module outlet fluidly connected to said fuel delivery module recycle fuel stream inlet;
- (3) a gas-liquid separator interposed between said exhaust module inlet and said exhaust module outlet, said separator comprising:
- (i) a first chamber comprising an inlet for admitting said anode exhaust stream into said first chamber and an outlet for discharging said recycle fuel stream from said first chamber to said fuel delivery module recycle fuel stream inlet,
- (ii) a second chamber comprising an exhaust module outlet for discharging a gaseous exhaust stream comprising at least some of said un-reacted fuel stream constituents, if any, and at least some of said anode reaction products, and
- (iii) a gas-liquid separator membrane interposed between said first chamber and said second chamber, said separator membrane capable of allowing diffusion of at least a portion of said gaseous exhaust stream constituents from said first chamber to said second chamber;
- whereby, when said fuel delivery module is coupled to said cartridge, and when said flow regulating mechanism is in an open position, said pressurized fuel stream is discharged from said cartridge module, and when said fuel delivery module flow regulating mechanism is in a closed position, said recycle fuel stream is admitted into said cartridge module.