Method of cooling a fuel cell

Chemistry: electrical current producing apparatus – product – and – With pressure equalizing means for liquid immersion operation

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Reexamination Certificate

active

06582844

ABSTRACT:

TECHNICAL FIELD
The present invention relates to a fuel cell having an electrolyte membrane sandwiched between an anode electrode and a cathode electrode.
BACKGROUND ART
Solid polymer electrolyte fuel cells comprise a plurality of stacked fuel cell structural bodies (unit cells) each comprising an electrolyte membrane in the form of an ion exchange membrane and a catalytic electrode and a porous carbon electrode which are disposed one on each side of the electrolyte membrane, and a plurality of separators sandwiching the structural bodies.
Hydrogen supplied to the anode of the fuel cell is converted into hydrogen ions on the catalytic electrode, which move through the electrolyte membrane that has been humidified to an appropriate extent toward the cathode of the fuel cell. Electrons generated while the hydrogen ions are moving are transferred to an external circuit for use as direct-current electric energy. An oxygen containing gas such as an oxygen gas or air is supplied to the cathode electrode to generate water through a reaction between the hydrogen ions, the electrons, and the oxygen on the cathode electrode.
For such a fuel cell, there has been known a structure which, as shown in
FIG. 11
of the accompanying drawings, comprises fuel cell structural bodies
2
and separators
4
which are alternately stacked together, each of the fuel cell structural bodies
2
having an electric generation section (electrode)
2
a
which is supplied with cooling water in a direction parallel to the flow of a fuel gas, e.g., a hydrogen gas and an oxygen containing gas, e.g., an oxygen gas.
Since the cooling water flows vertically in the electric generation section
2
a
, a relatively large temperature difference is developed between central and opposite side regions of the electric generation section
2
a
due to thermal diffusion. Because of a drop in the temperature, moisture is condensed in the opposite side regions of the electric generation section
2
a
, creating inoperative regions in the electric generation section
2
a
. In addition, the electric generation section
2
a
tends to have low-performance regions on account of the low temperature. As a result, the electric generation section
2
a
has its effective operative area and performance greatly lowered.
It is an object of the present invention to provide a fuel cell which will solve the above problems and has a simple structure for preventing partial temperature differences from being developed in fuel cell structural bodies thereby to maintain an effective operative area and performance.
SUMMARY OF THE INVENTION
According to the present invention, a cooling medium, which has been used to cool an electric generation section of a fuel cell structural body, is then circulated along outer sides of the electric generation section. Therefore, the cooling medium whose temperature has been increased by a heat exchange in the electric generation section flows outside of the electric generation section. Consequently, any temperature difference between a central region of the electric generation section and outer edges thereof is minimized, thereby preventing moisture condensation and increasing an effective operative area and the performance of the electric generation section.


REFERENCES:
patent: 3881956 (1975-05-01), Williams
patent: 5858567 (1999-01-01), Spear, Jr. et al.
patent: 60-038127 (1985-02-01), None
patent: 61-198571 (1986-09-01), None
patent: 2-50963 (1990-04-01), None
patent: 5-021076 (1993-03-01), None
patent: 6-267567 (1994-09-01), None
patent: 6-333580 (1994-12-01), None
patent: 07-142078 (1995-06-01), None
patent: 08-130028 (1996-05-01), None
patent: 8-167424 (1996-06-01), None
patent: 94/15377 (1994-07-01), None
European Search Report Communication for EP 96928695 Application dated Apr. 5, 2001.
English Language Abstract of JP 5-21076.
English Language Abstract of JP 8-130028.
English Language Abstract of JP 8-167424.
English Language Abstract of JP 6-267567.
English Language Abstract of JP 6-333580.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Method of cooling a fuel cell does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method of cooling a fuel cell, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of cooling a fuel cell will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-3163681

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.