Method and apparatus for vaporizing fuel for a reformer fuel cell system

A fuel cell system including:

• a fuel reservoir for storing a liquid fuel for a fuel cell;
• a fuel cell for consuming a fuel and generating electricity therefrom;
• a fuel reformer for receiving fuel in a vaporized state and connected to the fuel cell for providing a fuel thereto for consumption therein;
• and
• a fuel vaporizer interposed between the fuel reservoir and the fuel reformer for receiving liquid fuel from the fuel reservoir and vaporizing the liquid fuel to the vaporized state for delivery to the fuel reformer, and including a heat exchanger having a hot fluid inlet, a hot fluid outlet and a core interconnecting said inlet and said outlet, said core having alternating hot fluid passages extending between said hot fluid inlet and said hot fluid outlet and in heat exchange relation with liquid/vaporized fuel passages, said hot fluid passages each including a fin or fins and extending the length thereof and two separator plates bonded to and sandwiching said fin(s), said heat exchanger further including a liquid fuel inlet and a vaporized fuel outlet, said liquid/vaporized fuel passages extending between said liquid fuel inlet and said vaporized fuel outlet and including two abutting plates, each having elongated slots or grooves therein and extending diagonally to the mean direction of fuel flow in said liquid/vaporized fuel passages with the slots or grooves in one plate criss-crossing the slots or grooves in the other plate to be in fluid communication therewith, said slots or grooves having a progressively decreasing angle with the mean direction of fuel flow through said fuel vaporizer from said liquid fuel inlet to said vaporized fuel outlet.

A fuel cell system including:

• a fuel reservoir for storing a liquid fuel for a fuel cell;
• a fuel cell for consuming a fuel and generating electricity therefrom;
• a fuel reformer for receiving fuel in a vaporized state and connected to the fuel cell for providing a fuel thereto for consumption therein;
• and
• a fuel vaporizer interposed between the fuel reservoir and the fuel reformer for receiving liquid fuel from the fuel reservoir and vaporizing the liquid fuel to the vaporized state for delivery to the fuel reformer, and including a heat exchanger having a hot fluid inlet, a hot fluid outlet and a core interconnecting said hot fluid inlet and said outlet, said core having alternating hot fluid passages extending between said hot fluid inlet and said hot fluid outlet and in heat exchange relation with liquid/vaporized fuel passages, said hot fluid passages each including a fin or fins and extending the length thereof and two separator plates bonded to and sandwiching said fin(s), said heat exchanger further including a liquid fuel inlet and a vaporized fuel outlet, said liquid/vaporized fuel passages extending between said liquid fuel inlet and said vaporized fuel outlet and including two abutting plates, each having elongated flow passages therein and extending diagonally to the mean direction of fuel flow in said liquid/vaporized fuel passages with the flow passages in one plate criss-crossing flow passages in the other plate to be in fluid communication therewith, said flow passages having a progressively increasing width from said liquid fuel inlet to said vaporized fuel outlet.

A fuel cell system including:

• a fuel reservoir for storing a liquid fuel for a fuel cell;
• a fuel cell for consuming a fuel and generating electricity therefrom;
• a fuel reformer for receiving fuel in a vaporized state and connected to the fuel cell for providing a fuel thereto for consumption therein;
• and
• a fuel vaporizer interposed between the fuel reservoir and the fuel reformer for receiving liquid fuel from the fuel reservoir and vaporizing the liquid fuel to the vaporized state for delivery to the fuel reformer, and including a heat exchanger having a hot fluid inlet, a hot fluid outlet and a core interconnecting said inlet and said outlet, said core having alternating hot fluid passages extending between said hot fluid inlet and said hot fluid outlet and in heat exchange relation with liquid/vaporized fuel passages, said hot fluid passages each including a fin or fins and extending the length thereof and two separator plates bonded to and sandwiching said fin(s), said heat exchanger further including a liquid fuel inlet and a vaporized fuel outlet, said liquid/vaporized fuel passages extending between said liquid fuel inlet and said vaporized fuel outlet and including two abutting plates, each having elongated slots therein and extending diagonally to the mean direction of fuel flow in said liquid/vaporized fuel passages with slots in one plate criss-crossing slots in the other plate to be in fluid communication therewith, and separator plates bonded to and sandwiching said abutting plates, said slots having a progressively increasing width from said liquid fuel inlet to said vaporized fuel outlet.

A fuel cell system comprising:

• a fuel cell;
• a source of liquid fuel for said fuel cell;
• and
• a fuel vaporizer interposed between said fuel cell and said source for vaporizing liquid fuel received from said source and providing vaporized fuel to said fuel cell, said vaporizer including a fuel passage structure in heat exchange relation with a passage for a heated heat exchange medium and defined by at least one fuel passage sheet having a plurality of fuel flow areas therein, an inlet at or near one end of said sheet connected to deliver liquid fuel to said fuel flow areas, an outlet at or near an opposite end of said sheet and including an enlarged opening in the sheet connected to said fuel flow areas and serving as a collection manifold for vaporized fuel exiting said fuel flow areas, a pair of separator plates sandwiching said at least one sheet to close said fuel flow areas and said enlarged opening, at least one of said separator sheets including a series of raised, spaced dimples in said enlarged opening and contacting and bonded to the other of said separator sheets.

A fuel cell system comprising:

• a fuel cell;
• a source of liquid fuel for said fuel cell;
• and
• a fuel vaporizer interposed between said fuel cell and said source for vaporizing liquid fuel received from said source and providing vaporized fuel to said fuel cell, said vaporizer including a stack of fuel passage structures alternating with heated medium structures defining heated medium passages, each said fuel passage structure including at least one fuel passage sheet having a fuel flow area therein sandwiched between two first separator plates, each said heated medium structure including a fin located between two second separator plates, said second separator plates extending beyond opposite ends of said fuel passage plate and having aligned enlarged openings beyond said opposite ends serving as inlet and outlet manifolds in fluid communication with said heated medium passages, said second separator plates being sealed to each other about said enlarged openings except at a location establishing said fluid communication with said heated medium passages.

A vaporizer comprising:

• a plurality of fuel flow structures, each comprising two abutting fuel flow sheets sandwiched between first separator sheets, said fuel flow sheets having elongated slots therein extending at a progressively decreasing angle to a mean direction of fuel flow through said fuel flow structures and with increasing widths from one end of the fuel flow sheet to the other, the slots in one fuel flow sheet being in criss-cross relation with the slots in the other fuel flow sheet;
• a plurality of heated medium flow structures comprising a fin sandwiched between two second separator sheets, each second separator sheet extending beyond said ends of said fuel flow sheets and having first enlarged openings therein in alignment with one another at locations beyond said fuel flow sheet ends,
• said fuel flow structures and said heated medium structures being located in a stack in alternating relation with the fuel flow structures in the stack being aligned with one another and the heated medium structures in the stack being aligned with one another,
• a common fuel inlet to said fuel flow structures on a side of said fuel flow sheets near said one of said ends;
• a common fuel outlet from said fuel flow structure on a side of said fuel flow sheets near said other of said ends;
• second, aligned enlarged openings in said fuel flow sheets at said other end and intersecting some of said slots and connected to said common fuel outlet;
• a highly flow resistant maze in each of said fuel flow sheets at said one end and intersecting others of said slots and connected to said common fuel inlet,
• a common heated medium inlet at an end of said plurality of fuel flow structures and in fluid communication with said first enlarged opening thereat;
• and
• a common heated medium outlet at an end of said plurality of fuel flow structures and in fluid communication with said first enlarged openings thereat, said heated medium outlet being spaced from said heated medium inlet.

A fuel cell system including:

• a fuel reservoir for storing a liquid fuel for a fuel cell;
• a fuel cell for consuming a fuel and generating electricity therefrom;
• a fuel reformer for receiving fuel in a vaporized state and connected to the fuel cell for providing a fuel thereto for consumption therein;
• and
• a fuel vaporizer interposed between the fuel reservoir and the fuel reformer for receiving liquid fuel from the fuel reservoir and vaporizing the liquid fuel to the vaporized state for delivery to the fuel reformer, and including a heat exchanger having a hot fluid inlet, a hot fluid outlet and a core interconnecting said inlet and said outlet, said core having alternating hot fluid passages extending between said hot fluid inlet and said hot fluid outlet and in heat exchange relation with liquid/vaporized fuel passages, said hot fluid passages each including a fin or fins and extending the length thereof and two separator plates bonded to and sandwiching said fin(s), said heat exchanger further including a liquid fuel inlet and a vaporized fuel outlet, said liquid/vaporized fuel passages extending between said liquid fuel inlet and said vaporized fuel outlet and including two abutting plates, each having elongated slots therein and extending diagonally to the mean direction of fuel flow in said liquid/vaporized fuel passages with slots in one plate criss-crossing slots in the other plate to be in fluid communication therewith, and separator plates bonded to and sandwiching said abutting plates, said slots having a progressively decreasing angle with respect to the mean direction of fuel flow through said fuel vaporizer from said liquid fuel inlet to said vaporized fuel outlet.

A vaporizer comprising:

• a plurality of fluid flow structures, each comprising two abutting fluid flow sheets sandwiched between first separator sheets, said fluid flow sheets having elongated slots therein extending diagonally to a mean direction of fluid flow through said fluid flow structures and with increasing widths from one end of the fluid flow sheet to the other, the slots in one fluid flow sheet being in criss-cross relation with the slots in the other fluid flow sheet;
• a plurality of heated medium flow structures comprising a fin sandwiched between two second separator sheets, each second separator sheet extending beyond said ends of said fluid flow sheets and having first enlarged openings therein in alignment with one another at locations beyond said fluid flow sheet ends,
• said fluid flow structures and said heated medium structures being located in a stack in alternating relation with the fluid flow structures in the stack being aligned with one another and the heated medium structures in the stack being aligned with one another,
• a fluid inlet common to said fluid flow structures on a side of said fluid flow sheets near said one of said ends;
• a common fluid outlet from said fluid flow structure on a side of said fluid flow sheets near said other of said ends;
• second, aligned enlarged openings in said fluid flow sheets at said other end and intersecting some of said slots and connected to said common fluid outlet;
• a highly flow resistant maze in each of said fluid flow sheets at said one end and intersecting others of said slots and connected to said common fluid inlet,
• a common heated medium inlet at an end of said plurality of fluid flow structures and in fluid communication with said first enlarged opening thereat;
• and
• a common heated medium outlet at an end of said plurality of fuel flow structures and in fluid communication with said first enlarged openings thereat, said heated medium outlet being spaced from said heated medium inlet.

A vaporizer comprising:

• at least one fluid flow structure having an inlet, an outlet, a plurality of fluid flow passages of relatively low flow resistance connected in hydraulic parallel and located between said inlet and said outlet;
• a plurality of highly flow resistant mazes, one for each of said fluid flow passages and located upstream thereof;
• a common manifold connecting said mazes to said inlet;
• said outlet being connected to said flow passages at a downstream end thereof;
• and
• at least one heated medium flow structure in heat transfer relation with said fluid flow structure and the mazes and flow passages therein.