U.S. patent number RE35,002 [Application Number 08/290,141] was granted by the patent office on 1995-07-25 for fuel cell system.
This patent grant is currently assigned to Yamaha Hatsudoki Kabushiki Kaisha. Invention is credited to Toshiharu Hanahima, Hisayoshi Matsubara, Yutaka Mizuno.
United States Patent |
RE35,002 |
Matsubara , et al. |
July 25, 1995 |
Fuel cell system
Abstract
A fuel cell arrangement including an arrangement for improving
start up by heating the fuel cell through supplying selectively
heated exhaust gases from the reformer to the air port of the fuel
cell.
Inventors: |
Matsubara; Hisayoshi (Iwata,
JP), Mizuno; Yutaka (Iwata, JP), Hanahima;
Toshiharu (Iwata, JP) |
Assignee: |
Yamaha Hatsudoki Kabushiki
Kaisha (Iwata, JP)
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Family
ID: |
27335837 |
Appl.
No.: |
08/290,141 |
Filed: |
August 15, 1994 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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Reissue of: |
427756 |
Oct 26, 1989 |
05019463 |
May 28, 1991 |
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Foreign Application Priority Data
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Oct 28, 1988 [JP] |
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63-270764 |
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Current U.S.
Class: |
429/513;
429/423 |
Current CPC
Class: |
H01M
8/0267 (20130101); H01M 8/0612 (20130101); H01M
8/04223 (20130101); H01M 8/04225 (20160201); H01M
8/04014 (20130101); Y02E 60/50 (20130101) |
Current International
Class: |
H01M
8/04 (20060101); H01M 8/06 (20060101); H01M
008/04 () |
Field of
Search: |
;429/12,17,19,20,26,34,38,39,120 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Skapars; Anthony
Attorney, Agent or Firm: Knobbe, Martens, Olson &
Bear
Claims
We claim:
1. A fuel cell system for generating electrical power from a
reaction of a reformed fuel with air in said fuel cell comprising a
source of fuel, a reformer for reforming fuel from said source
through the application of heated air thereto, and valve means for
selectively supplying the heated air exhausted from said reformer
to an air port of said fuel cell for rapid start up or unheated air
to the air port of said fuel cell for normal operation thereof.
2. A fuel cell system as set forth in claim 1 further including
blower means for delivering the air to the fuel cell.
3. A fuel cell system as set forth in claim 2 wherein the blower is
positioned in the system for drawing air through an exhaust pipe of
the reformer.
4. A fuel cell system as set forth in claim 3 wherein the blower is
positioned between the reformer exhaust pipe and the air port of
the fuel cell.
5. A fuel cell system as set forth in claim 3 wherein the blower is
positioned downstream of the fuel cell.
6. A fuel cell system as set forth in claim .Iadd.1
.Iaddend.wherein the valve means comprises valve means for
selectively communicating the exhaust pipe of the reformer with the
air port of the fuel cell or with the atmosphere and for
selectively communicating atmospheric air with the air port of the
fuel cell when the exhaust pipe is not communicating with the air
port of the fuel cell.
7. A fuel cell system as set forth in claim 6 wherein the valve
means comprises a single four port, two way valve.
8. A fuel cell system as set forth in claim 7 wherein the valve
means comprises three two port, two way valves.
9. A fuel cell system as set forth in claim 7 wherein the valve
means comprises one three port, two way valve and one two port, two
way valve.
Description
BACKGROUND OF THE INVENTION
This invention relates to a fuel cell system and more particularly
to an improved arrangement for operating a fuel cell to insure that
it is brought to its operating temperature as rapidly as possible
and to insure that the fuel cell does not become overheated.
It is well known that electrical energy can be supplied from a fuel
cell that reacts an enriched or reformed fuel with air to produce
electrical energy. Such systems include a cell that has fuel and
air poles with an electrolyte matrix impregnated with an
electrolyte such as phosphoric acid interposed therebetween. The
devices operate with a hydrogen rich reformed gaseous fuel that
produces electrical power and water through an electrical chemical
reaction which is exothermic in nature. Because of the exothermic
nature of the reaction, the fuel cell is generally operated at a
temperature in the range of 200.degree. C. and has its temperature
maintained by means of a cooling jacket. However, when starting up
the fuel cell, it is important to insure that the operating
temperature is reached as soon as possible so as to permit full
power utilization and insure against the loss of energy.
Devices have been proposed for insuring more rapid start up through
the use of heaters for the air supply system that supplies the air
to the air pole of the fuel cell. However, such devices complicate
the system and also require electrical energy for their operation,
thus somewhat defeating their purpose. It has also been proposed to
raise the fuel cell system temperature by temporarily supplying
heated gas exhaust from the reformer to the cooling jacket.
However, the circulation of the heated exhaust air from the
reformer to the cooling jacket considerably complicates the piping
and plumbing system and also can give rise to the possibility of
overheating.
It is, therefore, a principal object of this invention to provide
an improved, simplified and highly effective fuel cell.
It is a further object of this invention to provide a fuel cell
arrangement wherein the fuel cell can be brought up to its
operating temperature as soon as possible without the use of
extraneous heating devices.
It is a further object of this invention to provide an improved
system for heating a fuel cell to its operating temperature
through-the use of the exhaust gases from the reformer as a heating
device for this cell without necessitating a separate heating
jacket or the use of these gases in the cooling jacket of the
cell.
SUMMARY OF THE INVENTION
This invention is adapted to be embodied in a fuel cell system for
generating electrical power from a reaction of a reformed fuel with
air in the cell. The system comprises a source of fuel and a
reformer for reforming the fuel from the source through the
application of heated air therethrough. Valve means selectively
apply the heated air from the reformer to the air port of the fuel
cell for warm up or unheated air thereto for normal operation.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partially schematic view of a fuel cell system
constructed in accordance with an embodiment of the invention.
FIG. 2 is a partially schematic view showing the air control valve
for the system in the non preheating mode.
FIG. 3 is a schematic view, in part similar to FIG. 2, showing the
air valve in the preheating mode.
FIG. 4 is a partial schematic view showing another embodiment of
the invention.
FIG. 5 is a partial schematic view, in part similar to FIGS. 1 and
4, and shows a still further embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE
INVENTION
Referring first in detail to FIG. 1, a fuel cell is identified
generally by the reference numeral 11 and is comprised of an
electrolytic matrix core 12 with fuel ports 13, air ports 14 and
cooling ports 15 disposed in laminated form therein so as to cause
an electrochemical reaction, as aforenoted. A reformer, indicated
generally by the reference numeral 16 and comprised of a vaporizer
17, heater 18 and catalytic core 19, which are provided for
supplying fuel to the fuel cell fuel port through a conduit 21. The
conduit 21 delivers the fuel from the reformer 16 to a reservoir 22
wherefrom it is delivered to the fuel port 13 through a supply
conduit 23.
The fuel to be reformed is supplied to the reformer 16 from a fuel
tank 24. The fuel contained in the fuel tank 24 is a reaction fuel
such as a methanol/water mixture that is reformed in the reformer
16 into a hydrogen rich reformed gas. A pump 25 supplies the fuel
from the tank 24 to the reformer 16.
The heater 18 of the reformer is also supplied with fuel from a
fuel tank 26 and this fuel may be of any known nature such as
methanol and is delivered by a pump 27 to the burner unit 18.
Forced air is supplied to the reformer 16 for combustion and
heating purposes from the atmosphere through a blower 28. The
heated air extends through a jacket of the reformer 16 and is
discharged through an exhaust pipe 29.
In accordance with the invention, a control valve means, indicated
generally by the reference numeral is provided for selectively
supplying atmospheric air from an atmospheric air inlet 32 to the
air port 14 and cooling jacket 15. In this condition, the exhaust
gases from the reformer exhaust pipe 29 are delivered to the
atmosphere through an atmospheric heating gas outlet 33.
Alternatively, the exhaust gas control valve means 31 is movable to
a position so as to supply heated exhaust gases from the reformer
exhaust pipe 29 to the air ports 14 and cooling jacket 15. It
should be noted that these exhaust gases are still rich in oxygen
since the reformer 16 operates with considerable excess air.
In the embodiment of FIGS. 1 through 3, the control valve means 31
is a four port, two way valve which in normal operating mode (FIG.
2) is disposed so that the exhaust gases from the reformer exhaust
pipe 29 are delivered to the atmosphere through the discharge 33
and atmospheric air is supplied from the inlet port 32 to a conduit
34 in which a blower 35 is positioned for delivery to the air port
14 and cooling jacket port 15. However, when starting up for quick
warm up, the valve means 31 is positioned in the position shown
in
FIG. 3 so that the exhaust pipe 29 communicates with the conduit 34
for supplying the heated air to the air port 14 and cooling jacket
port 15. In this condition, atmospheric air from the port 32 merely
communicates back with the atmosphere through the exhaust port 33.
This system continues to operate in this mode until the fuel cell
11 is at to the proper temperature at which case the valve 31 is
switched back to the position shown in FIG. 2.
It should be noted that the fuel exhausted from the fuel port 13
and fuel cell 11 is returned back to the burner 18 through a return
passage 36 so that no fuel will be wasted.
In the embodiment of FIG. 1, the blower 35 was positioned between
the valve 31 and the fuel cell 11. However, the blower 35 may be
positioned at any of a variety of locations such as in
communication with the exhaust port 37 of the fuel cell as shown in
phantom in FIG. 1.
In the embodiments thus far described, the control valve means 31
comprise a four port, two way valve. However, other types of valve
arrangements can be employed. FIG. 4 shows an arrangement wherein
the control valve means is comprised of a three port, two way valve
51 which selectively communicates the exhaust pipe 29 with either
the conduit 34 or the atmospheric discharge 33. In addition, there
is provided a two port, two way valve 52 that selectively
communicates with the conduit 34 downstream of the valve 51. The
valve 52 when closed will preclude any flow from the conduit 34 to
the atmospheric inlet 32. However, when the valve 52 is opened and
the valve 51 is closed, then atmospheric air will be supplied to
the air port of the fuel cell 11 as aforedescribed. Also, as
aforedescribed, the blower 35 may either be positioned in the
conduit 34 or in the exhaust conduit 37 as shown in the phantom
line views in this figure.
FIG. 5 shows another arrangement of control valve means which, in
this embodiment, include three two way, two port valves 101, 102
and 103. The valve 101 controls the communication between the
exhaust pipe 29 and an atmospheric exhaust gas discharge 33. When
closed, the valve 101 will direct the exhaust gases to the second
control valve 102. Normally the control valve 102 will be closed
when the control valve 101 is opened and vice versa. To this end,
the control valve 101 and 102 may be operated by a common operator.
The control valve 103, on the other hand, selectively communicates
an air inlet port 32 with the conduit 34 so that when the control
valve 102 is closed and the control valve 103 is opened, the system
will operate normally. However, when the control valve 101 is
closed and the control valve 102 is opened, the control valve 103
will be closed for heated start up. In addition to the valve
arrangements disclosed, other valve arrangements can obviously be
employed in conjunction with the invention operating on the
aforedescribed principles.
It should be readily apparent from the foregoing description that a
number of embodiments of fuel cell systems are disclosed, each of
which will provide rapid warm up with a minimum of external and
unnecessary plumbing or pipes. As noted, a variety of modifications
may be made without departing from the spirit and scope of the
invention, which is defined by the appended claims.
* * * * *