improvement of thermoelectric energy conversion -2
TRANSCRIPT
Nano-micron scale controlgrain boundary
grain alignment
Nano-micron scale controlgrain boundary
grain alignment
NanoNanoNano---micron scale controlmicron scale controlmicron scale controlgrain boundarygrain boundarygrain boundary
grain alignmentgrain alignmentgrain alignment
Improvement of Thermoelectric Energy Conversion by Hyper-structural Control
Atomic-nano scale controlelectrical conductivityphonon scattering
Atomic-nano scale controlelectrical conductivityphonon scattering
σ・α2Figure of merit: Z =
κ
σ・α2Figure of merit: Z =
κ
σ:Electrical conductivityα:Seebeck cofficientκ:Thermal conductivity
200 600 1000 1400Temperature / K
10-3
10-2
10-5
10-4
Fig
ure
-of-
mer
it,
Z/K
-1
n-Bi2Te3
n-SiGe
N-FeSi
Al-doped
ZnO
Li doped NiO
-SiC
SrPbO3
NaCo2O
4-poly
Sr-Ca2Co2O5 -poly
ZT=1
200 600 1000 1400Temperature / K
10-3
10-2
10-5
10-4
Fig
ure
-of-
mer
it,
Z/K
-1
n-Bi2Te3
n-SiGe
N-FeSi
Al-doped
ZnO
Li doped NiO
-SiC
SrPbO3
NaCo2O
4-poly
Sr-Ca2Co2O5 -poly
ZT=1
Thermoelectric power generation by n-p junction type cell module
Thermoelectric moduleheater
cooling stage
Thermoelectric ceramic module
Thermoelectric moduleheater
cooling stage
Thermoelectric ceramic module
Demonstration of the concept of an interactive material working as a device for NOx decomposition without any external energy or fuel by using the converted energy from exhaust gas heat to supply the electrical current to the electrochemical cell.
An example of Highly Interactive Materials--- deNOx without external energy supplying ---
Heat source
De-NOx Electro-chemical Cell
Thermoelectricmodulel
Heat source
De-NOx Electro-chemical Cell
Thermoelectricmodulel
1.For the first time an Electrochemical cells with multi layers electro-catalytic electrode for high selectivity of NOx decomposition and with a low value of cell operating current and power was designed.
2. Nano-structure control of electro-catalytic electrode was effective to dramatic improvement of de-NOx property of the cell. NOx-PM simultaneous purifying was realized by using oxygen radical reaction.
3. An interactive ceramic reactor consisted of de-NOx cell with thermo-electric module revealed 20%NOx decomposition without external power supply.
Summary of electrochemical reactors for NOx /PM decomposition
high efficiency on energy conversion and selective reactionhigh efficiency on energy conversion and selective reactionApplication of Advanced Ceramic Reactor
“Ceramic reactor”
Cell
moduleCube
ChemicalSyntheses
H2 Station
C H 4 →C O +H 2
O 2+N 2→N 2
O 2-2e
C H 4 →C O +H 2
O 2+N 2→N 2
O 2-2eNO x
→N 2+O 2OO 2
Environment Purifying
Fuel Cells
APU for Vehicles
Nanostructured electrochemical reactors for micro SOFCs
Nanotechnology
1
Elec
tric
al E
ffici
ency
(%
)
20
40
50
30
10 100 1,000
SOFC
PAFC
SOFC+GT
PEFC
MCFC
R&D Target
MicroSOFC
Power Output (kW)
Lean-burn GE,Atkinson cycle GE
GasTurbineGas
Engine
Power output vs Electrical Efficiency
APU applications for automobile
Delphi Gen1204kg, 155L
Delphi Gen33.6kW,70kg, 63LStartup 75min
Webasto
DevelopersSOFC-APU
Technical Hurdle ;
Rapid Startup
Heavy Duty Truck (Diesel ICE 3 – 6 kW)
Refrigerator Van (10 - 20 kW)
Passenger Car (Alternative Generator 3-10kW)
Applications
Future
NearFuture
Target (goal)Volume 5L Startup 5-15min
Key feature ; Compactness and Cost
Micro Tubular SOFC in the World
Adelan (UK)
ALPPS(Austria)
Primary Idea of Micro tubular SOFC ; Kendall / Sammes (UK)
EU: Original Idea
Adaptive Materials (US)
Mesoscopic Devices (US)
NanoDynamics (US)
US: Advanced Package for Military Applications
NanoDynamics (US)
ND50H; V=7L, W=5kg, Startup 15min
P=75W, 250WStartup10-15min, LPG Fuel, T=700C
TOTO (Japan)
AIST (Japan)
JAPAN: Advanced Core Modules
Research objective of the Advanced Ceramic Reactor
Solutions1)Rapid startup and stop → Small size unit cells
2)Reduced temperature operations → from >800C to 500-600C
3)Innovative low cost → Improve powerdensity per unit volume
Concept of “Ceramic reactor”
1) sub-millimeter tube unit cells
(0.5W/cm2@650C or under)
→ For rapid startup, Enhance electrode areas
2) Parallel integrated cell (pile of unit cells, 2kW/L)
3) Advanced ceramic processing and materials (nano -micro structure control)
Porous Cathode
Accumulation of high performance tubular SOFCs
Weak points of conventional SOFC
1)Startup-stop issue
2)High temperature operation (durability)
3)Cost reduction
1cm
Porous Cathode
PorousAnode
DenseElectrolyte1cm
Porous Cathode
PorousAnode
DenseElectrolyte
Micro Tubular Cells
seal
seal
Anode current collector
Anode Anode current current collectorcollector
seal
seal
Anode current collector
Cells integrated Cube
Interface construction
Fuel
Air
Fuel
Air
Ceramic Reactor Module
Interface construction円 小型 今回の
筒 チューブ ターゲット
形
0
5
Cub
e po
wer
den
sity
(kW
/ L)
Tubu
lar S
OFC
Smal
l Tub
e C
ell Micro Tube
CeramicReactor
(Our Target)
20
15
10
Cell diameter (mm)10 1 0.1
Development of Advanced Ceramic Reactor
Fuel(H2 etc.)Micro tube
Cube matrix
Air(O2) CGO/ScSZElectrolyte
Porous cathode(LSCF)
Anode(Ni-CGO)
Scheme of the research project3. Evaluation of prototype
module and application of advanced ceramic reactors
AIST, FCRA, Connecticut University, Toho Gas,CRIEPI, Denso Corporation
1. Development of highly active materials at low temperature operation
Mie University, Hosokawa Powder Technology Research Institute,Kyocera Corporation
The Advanced Ceramic Reactor Project(NEDO)July 2005 –March 2010Total budget; 2.1 Billion Yen
2. Development of the three dimensional fabricating
process of reactorsprocess of reactors
Natl.Inst.Advanced Industrial Science and Technl.(AIST),Fine Ceramics Research Association (FCRA:NGK,NGKNTK),Nagoya University, Japan Fine Ceramics Center, Toho Gas Co., Ltd.,Central Research Institute of Electric Power Industry(CRIEPI)
Core research site for the development offabricating technology
composite
hybrid
fine dispersion
nano meter -micron meter
scale
control of shape, size distribution and composition
CompositeHybridization
Hyper-structural and compositional control of electrodes and interfaces
Nanoparticle synthesis
network and distributionof pores and
matrix
Schema of the material development for electrodes and electrolytes
Selected Results 1. Development of highly active materials at low temperature operation
>Ni-SDC cermet anode fabricated from NiO-SDC composite powder
Hosokawa Powder Technology Research Institute
Ni-SDC anode supported cell with thin SDCelectrolyte achieved high electrical performanceat lower operation temperature (≦650ºC).
1um
1um 1um
Ni-GDC cermet anode fabricated from NiO-GDC composite powderNi-GDC cermet anode fabricated from NiO-GDC composite powder
Ni Ce
Morphology of cermet anodeNi-GDC/GDC/LSCF
anode supported cell
φ80mm
LSCF cathode
GDC electrolyte
10μmNi-GDC anode
1um
1um 1um
Ni-GDC cermet anode fabricated from NiO-GDC composite powderNi-GDC cermet anode fabricated from NiO-GDC composite powderNiNiNiNi-Ni--GDC -GDC GDC GDC GDC GDC cermetGDC cermetcermetcermetcermetcermet anode fabricated from NiOcermetanode fabricated from NiOanode fabricated from NiOanode fabricated from NiOanode fabricated from NiOanode fabricated from NiO-anode fabricated from NiO-GDC composite powder-GDC composite powderGDC composite powderGDC composite powderGDC composite powderGDC composite powderGDC composite powderGDC composite powderGDC composite powderNi-GDC cermet anode fabricated from NiO-GDC composite powder
Ni Ce
Morphology of cermet anodeNi-GDC/GDC/LSCF
anode supported cell
φ80mm
LSCF cathode
GDC electrolyte
10μm10μm10μmNi-GDC anode
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
0 0.5 1 1.5 2 2.5 3
C urrent density (A/cm 2)
Cell Voltage (V)
0.0
0.2
0.4
0.6
0.8
1.0
1.2
power density (W/cm2)
650℃測定600℃測定550℃測定PD-650PD-600PD-550
Ni-G DC /G D C /LSC Fの発電性能
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
0 0.5 1 1.5 2 2.5 3
C urrent density (A/cm 2)
Cell Voltage (V)
0.0
0.2
0.4
0.6
0.8
1.0
1.2
power density (W/cm2)
650℃測定600℃測定550℃測定PD-650PD-600PD-550
Ni-G DC /G D C /LSC Fの発電性能
Fabrication of micro-tubular GDC cell and cell characterization
Selected Results 2. Development of the three dimensional fabricating process of reactors
AIST
Cell Preparation0.8-1.8 mmΦ
NiO-GDC anode
tube
Dip-coating of electrolyte
Co-fired at 1450 C for 6h
Dip-coating of cathode
Sintered at 1000 C for 1 h.
0.8mm diameter anode tube
Anode tube
Electrolyte
Cathode
1.6mm diameter
0.8mm diameter
Micro SOFC
Anode tube
Electrolyte
Cathode
1.6mm diameter
0.8mm diameter
Micro SOFC
0 1 2 3 45
0.0
0.2
0.4
0.6
0.8
1.0
1.2
0.0
0.2
0.4
0.6
0.8
1.0
1.2
Po
we
r d
en
sity, W
/c
m2
Current density, A/cm2
570
550
500
450
NiO-GDC/GDC(20µm)/LSCF-GDC
0 1 2 3 45
0.0
0.2
0.4
0.6
0.8
1.0
1.2
0.0
0.2
0.4
0.6
0.8
1.0
1.2
Po
we
r d
en
sity, W
/c
m2
Current density, A/cm2
570
550
500
450
NiO-GDC/GDC(20µm)/LSCF-GDC
The micro SOFC fabricated as a tubular structure of 1 cm in length and 0.8-1.6 mm in diameter and revealed power densities of 1 W/cm2 at 570゚C, was obtained ---This value is on the world’s highest level in SOFCs with ceria based electrolytes ---
Integration technology ofcompact power modules
fuel
Air
1cm
Improvement offabrication technology for the stacked Modules(Cube)
Cell – stack – module fabrication
Developing Micro tubular IT-SOFC< 2.0mmΦ
AIST/FCRA(NGKNTK)
Successful Development of a Small, High-Performance Micro Fuel Cell Bundle- Realizes more than two watts of output power in a unit size of a sugar cube
(one cubic centimeter) below 600℃ (2W/cm3 @550℃)
0 1 2 3 4 5 60.4
0.6
0.8
1.0
0.0
0.5
1.0
1.5
2.0
2.5
電力
, W
電圧
, V
電流, ACurrent (A)
Volta
ge(V
)
Pow
er(W
)
0 1 2 3 4 5 60.4
0.6
0.8
1.0
0.0
0.5
1.0
1.5
2.0
2.5
電力
, W
電圧
, V
電流, ACurrent (A)
Volta
ge(V
)
Pow
er(W
)
Successful development of a small high power solid oxide fuel cell (SOFC) cubic bundle integrated very fine ceramic tubes in a volume of a sugar cube. The SOFC bundle generates the world’s highest output power density (two watts per
cubic centimeter) at an operating temperature of below 600 C, previously considered not possible for SOFCs that are normally operated at high temperatures.
LSM honeycomb
1616cells/cm2
GDC
NiO/GDC
LSM
GDC
NiO/GDC
100μm 10μm
0.7mm 0.7mm
Fabrication of Micro honeycomb SOFC
0
100
200
300
400
500
0 200 400 600
Time (sec)
Tem
p (C
)
-0.2
0.2
0.4
0.6
0.8
0
1
1.2
OC
V (
V)
Temp
OCV
N2 in
H2 in
5minstart
0 0.02 0.04
1
0.5
0
@ 450C
Voltage (
V)
Current density (A/cm2)
cyclic testing
(over 100 times)
LSM /ScSZ/NiO -G D C
Tim e (sec)
Voltage (V)
500 2000 25000
0.2
0.4
0.6
0.8
1
0 1000 1500
Redox test@ 700C
air inH 2 offN 2 in
N 2 in
H 2 in
100m A/cm 2100m A/cm 2
LSM /ScSZ/NiO -G D C
Tim e (sec)
Voltage (V)
500 2000 25000
0.2
0.4
0.6
0.8
1
0 1000 1500
Redox test@ 700C
air inH 2 offN 2 in
N 2 in
H 2 in
100m A/cm 2100m A/cm 2
Tim e (sec)
Voltage (V)
500 2000 25000
0.2
0.4
0.6
0.8
1
0 1000 1500
Redox test@ 700C
air inH 2 offN 2 in
N 2 in
H 2 in
100m A/cm 2100m A/cm 2
導電部材(SUS)
カソード側
アノード側
接続例stacking
Cathode side
Anode side
connector導電部材(SUS)
カソード側
アノード側
接続例stacking
Cathode side
Anode side
connector
0 0.05 0.1 0.150
1
2
0
0.5
1
1.5
Current density (A/cm2)
Vo
ltag
e (V
)
Vo
lum
etri
c p
ow
er d
ensi
ty (
W/c
m3)
@ 600C
Honeycomb stack
Honeycomb cell
ハニカムスタック評価結果例
Inter connector materials JFCC
Flexible sealing sheet(insulating)
Ag-Si-Ge alloy
Conductive sheet
Porous electrodes
sheet
3種類のシール材を用いた導電パスの構築
キューブ チューブ
インターフェース材料
導電シート材 絶縁シート材
導電パス構築
e-e-e-
e-e-e-O2-
O2-
空気極
固体電解質
燃料極
導電/絶縁シート材
3種類のシール材を用いた導電パスの構築
キューブ チューブ
インターフェース材料
導電シート材 絶縁シート材
導電パス構築
e-e-e-
e-e-e-O2-
O2-
空気極
固体電解質
燃料極
導電/絶縁シート材
Current-path design Interface materials
Cube
Conductive sheet Insulating sheet
Conductive/ Insulating sheet
TubeCurrent path
ElectrolyteAnode Cathode
Prototype bundle
Air
Fuel
Fig. Photograph of the prototype bundle composed of 36 Ni-GDC single cells.
Prototype bundlePrototype bundlePrototype bundlePrototype bundlePrototype bundlePrototype bundlePrototype bundlePrototype bundlePrototype bundleModelSize(with manifold) : 30 x 30 x 110 mm Size(electrode) : 30 x 30 x 30 mm Tubes : 36 Ni-GDC tubescurrent collector : Alloy plate + Ag mesh
50 mm30 mm
30 mm
Fuel : H2 900 ml/min, N2 900 ml/min
I / AThe performances of prototype bundle @500oC.
00.20.40.60.8
11.2
0 5 10 15 20 25 30
E / V
04812162024
Pow
er /
W14.2 W
3. Evaluation of prototype module and application of advanced ceramic reactors Selected Results
Max.40W@600C
Application of advanced ceramic reactors
Domestic stationary power sources
Systemconcept
kW SystemPackage
Analysis and evaluation of materials, cells, stacks and prototype modules to demonstrate utilities of the reactors
by TOHO gas
Test module
Demonstration of prototype module as APU unit for Automobile
Battery
Ceramic Reactor
AlternatorFuel Tank Engine
High performance compact APU
Micro SOFC module>rapid start-up/shut-down, fuel
Alternator
by DENSO
Mock-up model(200W class)
Portable power sources(clean & quiet)
>Advanced ceramic reactor project aims to develop - materials for electrolytes and electrodes of electrochemical reactors that
can be used at lower operation temperature and - a manufacturing process technology for integrating and arranging
structure of the materials in the micro level
>Goals are to develop a prototype micro-SOFC module that generates more than 2kW/L of power density at 650 ゚C or lower, with a rapid startup-shutdown performance for application to APU and cogeneration power unit and others.
>Micro tubular SOFCs with 0.8-1.6 mm diameter have been successfully fabricated. Advanced ceramic processing method developed in this project enabled to realize that the single tubular SOFC with ceria based electrolyte showed cell performance of over 1W/cm2 at 570゚C.
*over 3W/cm3 @550゚C by a sugar cube like cell-stack**Honeycomb SOFC (over 250 cells/cm3 ) and successful stacking process
>The new micro tubular SOFCs will be applied to build a compact power device with robustness by working in an accumulated cube-type stack.
>>> test module / prototype - by 2010.3
Summary of Micro SOFC development