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55-9
Creative process for Dispersing and Depositing Silver Nanoparticles
in Porous Ceramic Material - Process Doubles Output
Density of IT-SOFC -
Developed
by: CRIEPI
and AIST
* IT-SOFC = intermediate
temperature SOFC
* CRIEPI = Central Research Institute of Electric Power Industry)
* AIST = Advanced Industrial Science and Technology
A new process
for dispersing and depositing silver nanoparticles in a porous ceramic
material has successfully developed.
A mixed solution containing silver nitrate, citric acid, and ethylene
glycol is used for the process.
Citric acid is mixed into an aqueous solution of silver nitrate.
Silver is complexed. The air electrode is immersed into the resultant
solution.
The interior of pores of porous material is wet, and the silver
complex adheres to the inner surface of the pores.
The ethylene glycol in the solution, when heated, decomposes and
reduces the silver complex, while keeping its nano size, to thereby
form metallic silver particles.
The new process
does not need any special sputtering equipment, which has been used
for the vapor deposition of platinum.
No limit is put on an object to which the silver adheres by the
dispersion.
The process enables the silver particles to be deposited in the
ceramics material in a very simple manner.
The process will find a variety of applications.
CRIEPI and AIST
have succeeded in uniformly dispersing the silver nanoparticles
in the porous material of La0.6Sr0.4Co0.2Fe0.8O3 of the air electrode.
The photograph of Fig. 1 clearly shows islands of silver nanoparticles
(about 10nm).
The output density of the IT-SOFC (Fig. 3) using the air electrode
formed by dispersing silver nanoparticles thereon was measured.
The output density was 0.45 W/cm2(0.9 V, 0.5 A/cm2), and the maximum
output density was 1.06 W/cm2 (0.74 V, 1.43 A/cm2).
Incidentally, the output density of the conventional single cell
is 0.25 W/cm2(0.5 V, 0.5 A/cm2).
From those figures of the output density, it will be readily seen
that the output density of the IT-SOFC is remarkably improved.
For exact and
more information, please contact CRIEPI or AIST.
Photographs and
figures: http://criepi.denken.or.jp/jp/press/2006/12-04.pdf
Patent information: Pending
Background
SOFC development efforts progress toward achieving 800‹C
over of the operation temperature. Several hundreds kW-class SOFCs
systems have already been put in the demonstration test stage in
the laboratories in the world.
The operation temperature of the SOFC is high. Because of this,
it is difficult to increase the lifetime of the SOFC up to the lifetime
length (10 years or longer) in practical levels. It is also difficult
to operate the SOFC in circumstances where rapid temperature change
occurs. Other problems remain unsolved.
To increase SOFC applications, recent attention has been paid to
the intermediate temperature (IT) SOFC operating at 500 to 650‹C.
Many organizations and companies in the world are making research
of the SOFC while aiming at achieving 1) quick start/stop, 2) increase
of the lifetime, 2) cost reduction, etc.
If the SOFC operation temperature could be decreased to temperatures
around 650‹C, the lifetime of the SOFC will be further
increased, and reliability of the stack structure will be enhanced
using currently available, mass-produced, inexpensive metals.
To decrease the operation temperature of the SOFC, it is essential
to thin the electrolyte having the highest electric resistance among
the cell parts and also to enhance the properties of the air electrode.
The air electrode
properties, inter alia, the electric resistance and the catalytic
activity are of significantly importance.
With decrease of the operation temperature, the catalytic activity
considerably loses its effectiveness to hinder the increase of the
cell output power.
The conductive ceramics has been used for the air electrode.
Because of this, the air electrode exhibits high electric resistance
the value of which is higher than that of the fuel electrode made
of Ni metal by one digit magnitude or more.
In the cell-integrated module, the current collection resistance
of the air electrode occupies the most of the internal resistance
of the whole fuel cell.
To seek solutions to the problems, the research was made aiming
at enhancing the catalytic activity of the air electrode material
and at reducing its electric resistance by uniformly dispersing
silver nano particles exhibiting high catalytic activity and low
electric resistance over the surface of the air electrode.
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55-8
Basic Technology for Utilizing Hydrogen for Heat and Power Sources
in Buildings and Factories
Takasago Thermal
Engineering Co., Ltd. and AIST have succeeded in establishing a
basic technology of a system for utilizing hydrogen energy for the
heat sources and the power sources in commercial buildings, apartment
houses, etc.
The technique developed this time is a design technique of a hydrogen
storage tank within which special pipes are arranged
Hydrogen is stored
in a nickel hydrogen storage alloy contained in a tank.
For electric power generation, hydrogen is supplied from the tank
to the fuel cell.
For heat generation, endothermic energy and exothermic energy generated
when the hydrogen storage alloy absorbs and releases hydrogen are
utilized though water flowing through the pipes arranged in the
tank.
The hydrogen storage tank allows the user to utilize the amount
of heat, which is about 100 times as high as that of the usual heat
storage of the type which heats and cools water by electric power
in terms of volume ratio. The experiment showed that the hydrogen
storage tank was capable of supplying the amounts of electric power
and heat, which are comparable with those of the 5kW class power
generation equipment.
Source: Fuji
Sankei Business i
Takasago
Thermal Engineering Co., Ltd.
Planning, design, construction, and maintenance for buildings, factories
and facilities: System engineering, mainly of air conditioners
AIST
(advanced industrial science and technology)
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55-7
Ebara-Ballard Corporation
Completes Mass Production Factory for Stacks "V3"
Ebara-Ballard
Corporation has completed a factory for the mass
production of the fuel cell stacks "V3" in Ebara's Fujisawa
plant in Kanagawa prefecture. The stack "V3" is assembled
into the residential FC cogeneration system, which achieved 40,000
hours as its endurance lifetime. The company will be ready for mass
production of the residential 1kW FC cogeneration systems, of which
the real commercialization will start from 2008. As already reported,
the 3-year large-scale demonstration tests are presently conducted
and will continue till 2007. A total of 700 cogeneration systems
have been tested. 1,000 cogeneration systems will additionally be
tested. The company has received an order of 100 units (gas reformer
type) in 2005, and additionally 250 units (75 units = kerosene reformer
type) in 2006.
Source: Nikkan
Kogyo Shimbun Ltd.
|
55-6
New Hydrogen Sensor Useful for Hydrogen Leakage Sensing
Broad concentration range - 0.5ppm to 5%
We have demonstrated the performance of a newly-designed
micro-thermoelectric hydrogen sensor. Integration of thermoelectric
thin film of SiGe and ceramic catalyst into a micro hot plate on a
thin membrane has improved its performance, allowing for detection
of a wide range of hydrogen concentration in air from 0.5 ppm to 5
v/v %.
Developed byAIST,
Mr. W. Shin, researcher)
For details of
this news item, please read 52-4
"0.5ppm to 5%: Fairly Broad Sensing Range of New Innovative
Hydrogen Sensor" (already reported).
AIST presently
accepts the requests for samples of the prototype of the hydrogen
sensor element developed this time according to the AIST's sample
providing system.
Relevant articles:
1) M. Nishibori., J. Ceram. Soc. Japan, vol.114, p 853-856 (2006)
2) Japanese patent application No. 2005-67297
Title: FINE PATTERN FORMING METHOD
Priority information:
Priority number : 2004201213
Priority date : 07.07.2004
Priority country : JP
3) Japanese patent application No. 2005-024115
Title: THERMOELECTRIC GAS SENSOR MADE INTO MICROELEMENT
Priority number : 2004075982
Priority date : 17.03.2004
Priority country : JP
*************************************************************************
a) Abstract
Descriptions of those applications No. 2005-67297:
[Problem]
To provide a fine pattern forming method of a functional material.
[Solution]
In this fine pattern forming method, functional material of a raw
material for a catalyst or a resistor is designed and prepared,
while the fine structure thereof is controlled, the raw material
for the catalyst or the resistor is delivered, while a dispenser
three-dimensionally, to be applied in a prescribed position on a
substrate with a prescribed pattern is moved; and a fine pattern
is formed thereby under the condition where the fine structure including
a shape of a particle of a main component in the functional material
and including a distribution state thereof is controlled, in a gas
sensor for detecting, as a detection signal, the heat generated
by a catalytic reaction of an inflammable gas with a catalytic material,
or a thermoelectric generator for converting heat into electricity.
The present invention provides also the gas sensor and the thermoelectric
generator formed with the fine pattern.
b) Japanese patent
application No. 2005-024115
Title: THERMOELECTRIC GAS SENSOR MADE INTO MICROELEMENT
[Problem]
To provide a thermoelectric gas sensor, made into a microelement,
particularly an inexpensive contact combustion type micro gas sensor,
capable of identifying the gas kind from a combustible mixed gas,
using a simple structure.
[Solution]
This micro thermoelectric gas sensor comprises a thermoelectric
conversion part, a microheater, a catalyst layer formed on the microheater
and heated by the microheater, the catalyst layer working as a catalyst
catalytically burning a combustible gas, and a sensor part including
an electrode pattern therefor, which are formed on the membrane
of a predetermined thickness. According to this, power consumption
can be reduced, and high sensitivity concentration measurement and
high-speed response can be attained.
Note) The descriptions
of the relevant articles 2) and 3) were retrieved from "Searching
PAJ".
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55-5
New High-Pressure Electro-Osmotic Micro-Pump For Micro
Fuel Cells
Developed by CASIO Computer Co., Ltd. in cooperation with Nano Fusion
Technologies, Inc.
The new EO (electro-osmotic)
micropump is designed to be optimumly applied to the reformer-type
fuel cells for powering mobile devices. The micropump is indispensable
for the size reduction of the fuel cell.
The EO micropump uses the electro-osmotic material (7mm (diameter)
x 1mm (thickness)) developed by Nano Fusion Technologies.
The micropump takes a tubular shape made of the electro-osmotic
material (dielectric material, e.g., silica, generates electric
potential when it contacts liquid). The liquid flows in the micropump
when voltage is applied to the micropump. In principle, when voltage
is applied to the electrode of the porous electro-osmotic material,
excessive cations in the liquid migrate toward the negative electrode.
The migrating cations drag the whole liquid to form a liquid flow
with the aid of the viscosity of the liquid per se, providing the
pumping function.
The micropump, which uses no rotating part, is free from noisy sound
generation and the pulsation disturbance.
The new EO micropump
has the following specifications:
| |
Liquid
feeding principle |
Electro-Osmotic
flow |
| |
Volume
(size) |
0.5cc
(11 wide x 11 depth x 4 height: in mm) |
| |
Operating
fluid |
60wt%
MeOH liquid solution |
| |
Operating
voltage |
30V |
| |
Flow
rate vs. pressure |
120m/min.
at 0kPa (back pressure)100m/min. at40kPa90m/min. at 100kPa |
| |
Power
consumption |
100mW |
As seen from
the table, the EO micropump of 0.5cc (volume) is capable of feeding
methanol of 90ƒÊl/minute even at 100kPa under precise
control
The electro-osmotic material is weak in impact, and has a tendency
to be electrolyzed to generate gas. Those drawbacks have been successfully
solved.
The company is plan to deliver samples for performance evaluation
in 2007.
"System Ver. 35" incorporating the EO micropump was demonstrated
in "FC Seminar 2006", November 13 to 17 in Hawaii.
For more and exact
information, ask the company or contact us.
For photographs: visit at:
http://www.casio.co.jp/release/2006/EO_pump.html
CASIO Computer
Co., Ltd.
http://world.casio.com/
Micro reformer module for generating hydrogen from methanol,
power-generation cell stack
Nano Fusion Technologies,
Inc.
http://www.nft-eop.co.jp/index.html
nft-info@nft-eop.co.jp
http://www.conduit-ventures.com/article_flat.fcm?articleid=860&subsite=5967
Products: http://www.nft-eop.co.jp/lineup.html
Electro-osmotic devices: general purpose and micro-chip driving
electro-osmotic micropumps, peripheral devices
"FC
Seminar 2006": http://www.fuelcellseminar.com/
Fuel
Cell Today
|
55-4
Electrode Support Type SOFC
Having Micro-mm Honeycomb Structure Developed by AIST
- More than 250 SOFC cells per cubic cm -
Developed by
AIST
(advanced industrial science and technology,
Toshiaki Yamaguchi)
FCRA (see "MOT
for Ceramics")
NGK
Insulators, Ltd.
A process of fabricating
SOFCs of a micro-honeycomb structure has been uniquely developed.
The process is capable of fabricating more than 250 SOFCs per cubic
centimeters. The technology opens the way to realize an SOFC module
withstanding such a thermal shock as the rapid start/stop of within
several minutes from room temperature.
This SOFC
technology will be presented in Cocoabeach Conference, January 22,
2007, Florida in U.S.A.
The SOFC
is highly efficient and reliable, and easy in its handling.
However, it has been used only in an environment which allows it
to continuously operate at high temperature of 800‹C
or higher.
To expand its application, efforts have been made how to operate
it at low temperatures, to reduce the space used by the power generation
module, and to give it the rapid start/stop performance.
The SOFC fabricating technology successfully presents satisfactory
solutions to those problems.
Realization of the SOFCs, which are applicable to the auxiliary
power source for the vehicle, the small cogeneration system, and
portable power source, is in sight.
Technology
Briefing
A manganese perovskite (LSM) porous honeycomb structure of 15mm
x 15mm (square rod) as shown in the left photograph of
Fig. 1
was manufactured by a kneading extruding process.
The submillimeter-size
square channels of in the honeycomb were simultaneously coated by
an electrolyte slurry of scandia stabilized zirconia (ScSZ) or ceria
base oxides (e.g., GDC) by using a specially designed tool. After
dried, the resultant was fired at 1300 degrees of centigrade.
Following this process, the resultant was coated by a nickel slurry
containing ceria base oxides i50vol%Ni-GDCjand fired
at 100 degrees of centigrade or higher.
As a result, a fine electrolyte film of 20µ thick and an NiO-GDC
layer as a porous electrode were formed on each channel wall in
the porous electrode honeycomb substrate. This structure was formed
in each of the 256 spaces.
The thus formed honeycomb SOFCs were subjected to rapid (several
minutes) heating and cooling tests.
The result was that none of the cell structures were destroyed,
and that the SOFCs could withstand the rapid heating and cooling.
A power generation test of the manufactured fuel cells was conducted
by using humidified hydrogen.
As a result of the test, it was confirmed that the power generation
performance of the SOFC (LSM-GDC) was 0.23W/cm2 (700°C). This
figure is at the world's highest level in the medium temperature
region.
It was also confirmed that the technology developed at this time
could be used as the technology for forming small and high density
SOFC cells.
For exact
and more information, please contact Yoshida or Yoshizawa: chubu-kouhou@m.aist.go.jp.
NGK
Insulators, Ltd.
Products: power, ceramic products, engineering,
electronics, life science
|
55-3
TORAY's Molecular Structure Control Technology Realizes
Fuel Cell Hydrocarbon Electrolytic Membrane - Durability
reaches practical level -
Developed by
TORAY
Industries, Inc: http://www.toray.com/
For exact and more information on this new technology, please ask
the company.
The hydrocarbon
electrolyte membrane developed is innovative.
The mechanical properties of the membrane are materially improved:
tensile elongation = about 1.3 times, tensile strength = about 3
times, modulus of elasticity = about 10 times, and tear strength
= about 4 times (when compared to those of the fluorine-based electrolyte
membrane, measured at 0.1S/cm (proton conductivity by the company).
The tensile elongation and the tear strength are about 2.5 times
and 5 times when compared to those of the conventional hydrocarbon
electrolyte membrane (measured by the company).
The new hydrocarbon electrolyte membrane has successfully overcome
the largest faults of the conventional hydrocarbon electrolyte membrane:
it is hard and fragile.
This
leads to the long durability and long lifetime of the membrane.
Those figures were achieved while securing high proton conductivity.
>> More
(No. 55)
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55-2
Reinforced
Gathering Of Data From Individual Monitors Of Residential FC Cogeneration
Systems
Nippon
Oil Corporationn has incorporated "learning function"
into the FC control system for the residential FC cogeneration system.
The "leaning function" contained FC control system has
started its assembling into the cogeneration systems having been
and to be shipped in the latter half year.
The system gathers data from the individual FC cogeneration systems
and learns the operating conditions and behavior of each home FC
cogeneration system, and optimumly controls the operations of the
cogeneration system in accordance with the cogenerator operation
behavior of each home to maximize the operation efficiency.
The company has developed residential FC cogeneration systems of
the LPG- and petroleum-reformer types, and has started launching
them into the market on March this year. More than 400 FC cogeneration
systems are presently running at residential homes in Japan. The
petroleum-based FC cogeneration system is named as "ENOOS ECOBOY".
The maximum power output of the FC cogeneration system is 1kW, about
60% of the total electric power consumed by an average home in Japan.
Idemitsu
Kosan Co., Ltd. has organized special agents dealing
in the residential FC cogenerations. The name of the organization
is "FC Net". All the parts of the country are grouped
into 7 blocks. A meeting will be held two times a year in each block.
The company intends to more elaborately gather data from the cogenerator
monitors.
Sources: Nippon Oil Corporation, Idemitsu Kosan Co., Ltd., FujiSankei
Business i.
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55-1
Fuel Cell Separators And Electric Double Layer Capacitors
Will Enter Full-Scale Commercialization In The Next Year
Nisshinbo Industries, Inc. will enter full-scale
commercialization of@fuel cell separators and electric double
layer capacitors.
The company is presently considering candidate locations for a new
plant and production ability of the plant, and has a plan to have
a black-ink balance within 2008. The company's decision on the commercialization
seems to be based mainly on the two factors. The company's separator
have been recognized as de facto standard, and the double layer capacitor
has been employed in the NEDO projected.
Nisshinbo,
in cooperation with Japan Radio Co., Ltd., succeeded in developing
a new double layer capacitor of 18.2kW/L (power density). The power
density ranks at the world's top level.
| |
Capacitance
|
Power
density (kW/L) |
| |
250F
|
18.2 |
| |
500F
|
15.6 |
| |
1000F
|
13.5 |
The electrode
material and structure are optimized and the internal resistance
is halved compared to that of the conventional one.
The charge/discharge efficiency is improved with less deterioration
by heat
The charge/discharge performance of the battery is high also in
low temperature condition of 30 degrees of centigrade.
A trade name of the new capacitor is "N's CAP".
The new battery was exhibited in EVS (international battery, hybrid
and fuel cell electric vehicle symposium), October 23 to 28, 2006.
The electric double layer capacitor 15V was incorporated in the
electric car C-CMOS as one of test cars in EVS.
If the new battery is used as the peak assist power source, the
electric double layer capacitor module will find many uses particularly
in the fields of automobile, construction and industrial equipment
where it is required to frequently repeat the charging/discharging
operation at large current.
Photograph: http://www.nisshinbo.co.jp/press/pdf/061018_NsCAP.PDF
Nisshinbo
Industries, Inc.
http://www.nisshinbo.co.jp/english/index.html
Japan Radio Co., Ltd.
http://www.jrc.co.jp/eng/index.html
Source: Daily
Chemical Co., Ltd. : http://www.chemicaldaily.co.jp/
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