29/09/2009 DOE TE Applications Workshop 1 Overview of Japanese Activities in Thermoelectrics Takenobu Kajikawa Shonan Institute of Technology
29/09/2009 DOE TE Applications Workshop 1
Overview of Japanese Activities in Thermoelectrics
Takenobu KajikawaShonan Institute of Technology
29/09/2009 DOE TE Applications Workshop 2
Outline
•
Introduction
•
Overview of R and D Projects on Thermoelectric Power Generation Technology
•
Several Topics and Future Prospects
•
Conclusions
29/09/2009 DOE TE Applications Workshop 33
3-Key Viable Missions of Thermoelectric Power Generation Technology
Economy
Energy Security Environmental Conservation
Activation of new industry
Thermoelectric Power Generation Technology
Creation of energy resources from waste heat
Energy conservation
Reduction of Carbon emission
Principal Recognition:Thermoelectric technology can contribute to the realization of environment-friendly society all over the world in the future.
29/09/2009 DOE TE Applications Workshop 4
Micro-Grid System
in the future power grid system
制御システム
太陽光発電 風力発電
ボイラ
病院
加熱炉
工場
バイオガスエンジン
農場
一般家庭
NaS電池
燃料電池(SO FC )
熱電発電システム
電線
通信線
配電用変圧器
変電所
集合住宅
燃料電池(PEM )
制御システム
太陽光発電 風力発電
ボイラ
病院
加熱炉
工場
バイオガスエンジン
農場
一般家庭
NaS電池
燃料電池(SO FC )
熱電発電システム
電線
通信線
配電用変圧器
変電所
集合住宅
燃料電池(PEM )
Photo Vol
taic
Private Sector
Wind Power
Furnace
Power Grid
Fuel Cell
Transformers
Communication Grid
Fuel Cell
Boiler
Biogas
Farm
Hospital
TEG-system
NaS Battery
Apartment
Factory
Substation
Control system
Thermoelectric power generation systems can be applied to all kinds of waste heat sources in the micro grid systems, which are expected to play an important role in the efficient energy system in the future.
Combined with Main power Grid
Main Grid
29/09/2009 DOE TE Applications Workshop 5
Former R&D Projects on Thermoelectric Power Generation in Japan
FY 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006
R eduction of Exhaust of C O 2 (N ED O --> EN A A )
Eco-Energy P roject to constitute high efficient energy com m unity (N ED O ---> EC C )
Efficient U tilization of U nused Energy S ources such as H eat of S olid W aste (S T A ---> N ational Labs. Etc.)
T E S ystem using S olid W aste C om bustion H eat (M . of H & W ---> Japan W aste R esearch Foundation)
T E S ystem using Exhaust G as of G asoline Engine V ehicle
(N ED O ---> T echnology P rom otion C enter, C hugoku)
A dvance R esearch on H igh-Efficiency T herm oelectric T echnology
(N ED O ---> EC C , EN A A , U B E)
D evelopm ent for A dvanced T herm oelectric C onversion S ystem s
(N E D O ---> E N A A , eco21, IH I, K om atsu, T oshiba, U B E , Y am aha)
CREST
Proof of concept Economic feasibility Demonstration
Practical use for 1st
generationR&D for 2nd
generation
5
2-year Follow-upJATeCS
Nano block integration project
29/09/2009 DOE TE Applications Workshop 6
Ongoing and Initiated Thermoelectric R&D Projects in Japan
•
Development of High-Performance Thermoelectric Materials by Controlling Nano-
Structure of Caged CompoundsNEDO/METI, 2009.6-2017.3, Hiroshima Univ. ,Denso Co.Ltd, and 3 Institutes, \210M for 1st
stage / \600M for 2nd
stage,ZT~1.3,12%@DeltaT of 300K by advanced cage-structured materials
•
Development of High-Efficiency Thermoelectric Materials and SystemsCREST/MEXT,2008.10-2014.3,Nagoya Univ., and 3 Institutes,\227M,High-efficient materials such as layered oxides、Si-
based Clathrates and nanostructured
,ZT>1.5,ηsys~10%
・
Development of Thermoelectric MaterialsJST/MEXT,2008.9-2013.3, Nagoya Univ.,\40M,Basic research on high performance layered oxides combined low-dimension-structured materials
•
Development for High Temperature Thermoelectric Materials to recover unused waste heat sourcesNIMS/MEXT,2009.4-2014.3,NIMS,\22M,Complex structured materials such as RB17
CN and RB22
C2
N,and Higher Borides•
Research on Spin-Seebeck Effect for Innovative Thermoelectric MaterialsNEDO/METI,2009.6-2011.3,Tohoku Univ.,\25M,Basic research on technology assimilation between thermal insulation
material technology and spin electronics•
Development of Novel Thermoelectric Modules by Ink-jet TechniqueMEXT,2009.4-2013.3,JAIST and KELK,\26M, High performance and low cost thermoelectric modules based on nanoball
ink-jet technique
CREST
(Core Research for Evolutional Science and Technology), JST (Japan Science and Technology Agency) , METI (Ministry of Economy, Trade and Industry) , MEXT
(Ministry of Education, Culture, Sports, Science & Technology) , NEDO
(New Energy and Industrial Technology Development Organization) ,NIMS
(National Institute for Materials Science), JAIST
(Japan Advanced Institute of Science and Technology)
Description: Title/ Sponsor/ Term/ Organization/ Budget/ Goal
29/09/2009 DOE TE Applications Workshop 7
NEDO PROJECT for Novel Practical Materialsby Nano-Structuring, FY 2009-2011 (1st
stage)
Development of High-Performance Thermoelectric Materials by Controlling Nano-Structure of Caged Compounds
P.L.: Professor T. Takabatake,
Hiroshima UniversityT. Koyanagi, K. Akai, Yamaguchi University
K. Ueno, National Inst. of Advanced Industrial
Science and TechnologyT. Taguchi, DENSO Co., Ltd.K. Fukuda, KELK Co., Ltd.
Development of High-performance TEG Systems for Practical Use
FY2012-2014 (2nd
Stage)
Materials
Modules
Systems
29/09/2009 DOE TE Applications Workshop 8
Project Goal; ZT=1.3 at 200-300 ºC
Snyder, Nat. Mater. 7, 105 (2008).
double
BGS
p-type
Goal
BGS
n-type
Goal
・ Temperature range: Th
= 400 ºC, Tc
= 100 ºC, T = 300 ºC・ ZT
for previous materials has a
valley at 200-300
ºC
・ nano-scale caged material
Ba8
Ga16
Sn30
: ZT
=
0.8 for both n-
and
p-typesZT( 200-300 ºC )=0.6~0.7
Bi2
Te3
, PbTe
toxicZT =1.3
Safe,
nano-scale caged material
29/09/2009 DOE TE Applications Workshop 9
Important step: Introduction of different guest ions in the two type of cages
should lead to the coexistence of higher
and the sufficiently low .
Key Ideas and Methods: Nano-Structure Control of Caged Compounds
Ba8
Ga16
Sn30
Issue of Jan. 2008
ZT
=κ
S2σ
T1 nanometer
Electronsflow the networkof the cage
Heat
flow is scattered by off-center rattlingof the guest
Following the concept of “Phonon Glass
and Electron Crystal”
proposed by Slack, project teams of Hiroshima & Yamaguchi Universitieshave succeeded in reducing to 0.4 W/Km at 300 K by controlling the structure of intermetallic clathrates.
29/09/2009 DOE TE Applications Workshop 10
Japan Science and Technology Agency -
CREST Project<2008.10.1 ~ 2014.3.31>
“Exploration of Innovative Technology to Reduce Carbon Dioxide Emission”
Development of High-EfficiencyThermoelectric Materials and Systems
K. Koumoto
(Nagoya University)
Collaborating Group Leaders:R. Funahashi(AIST)H. Anno(Tokyo Univ. of Sci. )R. Suzuki(Hokkaido Univ.)M. Kusunoki
(Nagoya Univ.)
Ind. furnacesIncineratorsCars
Solar heatFuel cells
TE module TE system
Nontoxic,Nonhazardous,Nat. AbundantElements !
29/09/2009 DOE TE Applications Workshop 11
= + =
(1) Quantum Nanostructured Bulk Materials
0.0 0.1 0.2 0.3 0.4 0.5
2
3
4
5
6
7
8
9 1/16 2/16 4/16
Pow
ef F
acto
r (W
m-1K
-2)
GB barrier height (eV)
(10-3)
(a)
2DEGG.B.
Ba SiBa Si
ClathrateHigh-
efficiency Bulk material
Semicond.
Surfacemodification
PlanetaryBall milling
SparkPlasma
Sintering
(2) Si Clathrate Nanocomposite
3.5 mm
3.5 mm3 mm
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
0 1 2 3 40.0
0.5
1.0
1.5
2.0
2.5
3.0
Power (W
)
T=284 K
T=482 K
T=649 K
Volta
ge (V
)
Current (A)
T=785 K
Oxide/Bi2
Te3Cascade-typeModule
(3) TE Module Development
Non-dimensional length, XN
on-d
imen
sion
al p
ower
, (X)
X=0.9344のとき、max
=0.07147
(4) System Design
Phase1
Phase 2
29/09/2009 DOE TE Applications Workshop 12
Application Systems
T
(K)300 400 500 600 700 800 900 1000 1100Temperature
JATeCSTrans.
Co-generation
Industrial Electric Heating Furnace
Toshiba
Ube/eco21/Komatsu
IHI
ProjectorYamaha
Komatsu
Incinerator
Gas Water Heater/Furnace/Topping-up
Solar Thermal
OngoingsAIST
JAXA
Maebashi City., Ishikawa Pr.
Motorcycle
Hot Springs Kusatsu
Private company
(presented by Dr.R.funahashi)
4 years operation
Heusler module
Low Temp. application
China-Japan Joint Program/ Hybrid System
29/09/2009 DOE TE Applications Workshop 13
Over view of TE Materials
29/09/2009 DOE TE Applications Workshop 14
Topics on TE Materials Research-1
•
Environment-Friendly MaterialsHalf Heusler
Heavy Fermion Intermetallic
Higher Borides
Layered Oxides (presented by Dr.R.Funahashi)
MNiSn (M=Zr,Nb) ,ZT 0.66 (n),0.45 (p), at1000K
YbAl3Mx system, ZT was obtained 0.32 at 323K for Yb1.05Al3B0.1.
Alkaline-Earth Hexaborides (Ca,Sr)B6 ZT=0.35 was obtained at 1073K.
29/09/2009 DOE TE Applications Workshop 1515
Some Topics on the Enhancement Approaches due to
Nanostructure
Tech.•
Nanoblock integration
•
Nanovoid forming
•
Nanophase separation
•
Nanoparticle inclusion
Thermal conductivity reduced by 30-35%
with forming nanovoid in ZnAlO system. The ZT was 0.54-0.59 at 1273K: nearly two times more than that of no nanovoid dispersion.・・・Kyusyu Univ.
Nanophase separation effect for n-type half-Heusler (MA0.5,MB0.5)NiSn System (MA,MB=Hf,Zr,Ti) :The ZT increased from 0.55
for ZrNiSnto 0.9 at 873K.・・・Tokyo Inst. of Technology、AIST
The ZT increased from 1.1 to 1.22
at 773K for filled skutterudite CeFe3
CoSb12
-MoO2
composite .・・・Osaka Univ.
The ZT was obtained 2.4
at 300K for one cell layer of Nb doped SrTiO3
system.・・・Nagoya Univ.,Waseda Univ., AIST
29/09/2009 DOE TE Applications Workshop 1616
Future Prospects Approach to Commercialization of TE Power
Generation
1st
Step : Public Relations ; TE technology can contribute to the solutions of environmental issues, energy security and industry.
2nd
Step : Users ’
Acceptance of Full-grown TE Power Generation Technology ; Establishment of the commercial production line
3rd
Step : Establishment of TE Power Generation Industry and Market
Commercial TEG modules by KELK & Komatsu , and Yamaha as the outcome with JATeCS-project
29/09/2009 DOE TE Applications Workshop 1717
Near-term applications to be commercialized:Small-scale, low-temperature, and dispersed waste heat recovery systems
from all energy-utility fields using high-ZT-
Bi-Te based modules, or low-cost, environment-friendly, moderate-ZT-
materials based modules, and micro-
scale, multi-purpose TEG systems
Long-term applications:Large-scale (kW order) and wide-temperature range waste heat recovery systems, and topping-up TEG systems
Innovative thermoelectric material systems:
The Key is best-mix nano and robust nanotechnology.
Future Prospects
29/09/2009 DOE TE Applications Workshop 18
Conclusions•
Several ongoing projects on TEG technology in Japan are summarized, in which the goals in ZT are 1.3~1.5.
•
The effort to proceed the TEG technology has been intensively achieved for the small-scale applications and advanced materials.
•
Near-term applications to be commercialized are prospected to besmall-scale, low-temperature, and dispersed waste heat recovery systems from all energy-utility fields using high-ZT-
Bi-Te based modules, or low-cost, environment-friendly, moderate-ZT-
materials based modules
29/09/2009 DOE TE Applications Workshop 19
Thank you for your attention !!
Where there is heat, there is Thermoelectrics !!
29/09/2009 DOE TE Applications Workshop 20
Electrification Ratio in Japan ***Progress and Prospects***
Fiscal Year
The role of the electricity has been increasing year and year in
Japan. The high performance of power generation and the efficient use of energy resources are inevitable and urgent to sustain the electrified society.
29/09/2009 DOE TE Applications Workshop 21
Kusatsu Hot Springs TE Power Generation System: Continuous operation for nearly 4 years
since Dec. 26th,2005
The generated electricity has been consumed in TV ,illumination and display during the daytime, and for the charge to the battery in
the nighttime. The cumulative electric energy had been 1360kWh by August 22,2009.
Inverter
Battery
320 TE Modules
Temperature of the hot spring is 369K constant, and pH is1.46.
Cold channelsTE modules
Hot spring channels
29/09/2009 DOE TE Applications Workshop 22
Operating time (x104 h)
Gen
erat
ed e
nerg
y pe
r pow
er g
ener
atio
n un
it ar
ea (k
Wh/
m2 )
Thermoelectric power generation using hot springs Photovoltaic power
generation for 4kW residence
Relationship betw een integrated electricity per unit area and operating tim e :
Therm oelectric versus Photovoltaic
29/09/2009 DOE TE Applications Workshop 23Power Characteristics
Waste heat recovery from MotorcycleOn the streetsOn the test bench
TE system Load: LED
Supply of power
823K
Time variation of exhaust gas temperature
Annual production of motorcycles: 40M/y
Heusler alloy TE module
29/09/2009 DOE TE Applications Workshop 24
TEG demonstration systems to low temperature waste heat (<373K) from incinerator
in Maebashi City, Gunma Pref. ,and Ishikawa Pref.Press release on September 16th,2009
Rokyo Incinerator Plant ( Capacity: 405t/day)
TEG System
29/09/2009 DOE TE Applications Workshop 25
TEG demonstration system using Solar Thermal energy by JAXA-ARD
JAXA-ARD; Japan Aerospace Exploitation Agency-
Aerospace Research & Development Directrate
Fresnel lens
Plane Reflector
Selective Mirror
TE Modules PV
Hot Water Heat Sink
TE-PV Combined Solar System
Solar Irradiation
29/09/2009 DOE TE Applications Workshop 26
Half-Heusler Compounds
Cubic MgAgAs type structure VEC=8 or 18 : semiconductor/semimetal
XYZ
XYZ half-Heusler compounds
:Heusler type
N-type half-Heusler compounds;ZrNiSn based
: ZT=0.5~1.5 (1-4)
TiCoSb based : ZT=~0.3 (5)
NbCoSn based
: ZT=~0.3 (6)
TiCoSb based
: ZT=0.3~0.9 (7,8)
ZrPtSn : ZT=~0.1 (9)
ErPdSb : ZT=~0.2 (10)
P-type half-Heusler compounds;
1) C. Uher et al, Physical Review B, 59
(1999) 8615-8621. 2) Q. Shen et al, Appl. Phys. Letter, 79
(2001) 4165-4167. 3) Sakurada et al., Appl. Phys. Letter, 86 (2005), 082105.4) S.R. Culp et al., Appl. Phys. Letter, 88 (2006), 042106. 5) Y. Xia et al., J. Appl. Phys.,
88 (2000), 1952-1955.
6) Y. Ono et al, Proc. MRS, 793
(2003) 195-200. 7) T. Sekimoto et al, Appl. Phys. Letter, 79
(2001) 4165-4167. 8) Sakurada et al., Proc. MRS (2005).9) Y. Kimura et al., Abst. Autumn Meeting JIM, (2005) 85-86.
10) T. Sekimoto et al., J. Appl. Phys.,
99 (2006), 103701.
MgAgAs structure
Reference Data:
29/09/2009 DOE TE Applications Workshop 27
Half-Heusler Compounds
: MNiSn (M=Zr,Nb)
by Prof. Yamanaka’s Group (Osaka Univ.)
200 400 600 800 1000 12000.00
0.25
0.50
0.75
1.00
1.25
1.50
Zr0.98Nb0.02NiSn
Zr0.5Hf0.5Ni0.8Pd0.2Sn0.99Sb0.01
Ti0.3Zr0.35Hf0.35NiSn0.94Sb0.06
SiGe
PbTe
Bi2Te3
BiSb
Dim
ensi
onle
ss fi
gure
of m
erit,
ZT
Temperature, T / K
The ZT
value was obtained 0.66 at 1000 K.
n-type
400 600 800 10000
0.1
0.2
0.3
0.4
0.5
ZT
T (K)
TiCoSnxSb1-x 0.0 #3 0.01 0.05 0.1
Ti0.5Zr0.5CoSnxSb1-x 0.0 0.1 0.15
ZrCoSnxSb1-x 0.0 0.05 0.1 0.15
The ZT=0.45 around 1000K for Sn doped ZrCoSb without no technique for reduction of thermal conductivity
p-type
29/09/2009 DOE TE Applications Workshop 28
2SP High Power factor
Rare-earth based heavy fermion intermetallic compoundsby S.Katsuyama’s Group (Osaka Univ.)
Large effective mass: m* =15‐30me
Reduction of thermal conductivity ※Bi2
Te3
P~5000μWm-1K-2
(300K)
P~15000μWm-1K-2
(300K)
YbAl3
Mx
YbAl
300 400 500 60015
20
25
30
35
Temperature (K)
Ther
mal
Con
duct
ivity
(W/m
/K)
Yb1.05Al3Yb1.05Al3B0.05Yb1.05Al3B0.10Yb1.05Al3C0.05Yb1.05Al3C0.10
M
Phonon scattering due to rattling effect by M
300 400 500 6000.1
0.2
0.3
0.4
Temperature ( K )
ZT
Yb1.05Al3Yb1.05Al3B0.05Yb1.05Al3B0.10Yb1.05Al3C0.05Yb1.05Al3C0.10
The ZT value was obtained 0.32 at 323K for Yb1.05
Al3
B0.10
system.
29/09/2009 DOE TE Applications Workshop 29
MCoSb (p-type) : ZT
by Prof. Yamanaka’s Group (Osaka Univ.)
Maximum ZT
TiCoSn0.1
Sb0.9
ZT
= 0.30 at 959 K
ZrCoSn0.1
Sb0.9
ZT
= 0.45
at 958 K
Ti0.5
Zr0.5
CoSn0.15
Sb0.85
ZT
= 0.44
at 904 K
400 600 800 10000
0.1
0.2
0.3
0.4
0.5
ZT
T (K)
TiCoSnxSb1-x 0.0 #3 0.01 0.05 0.1
Ti0.5Zr0.5CoSnxSb1-x 0.0 0.1 0.15
ZrCoSnxSb1-x 0.0 0.05 0.1 0.15
The ZT=0.45 around 1000K for Sn doped ZrCoSb without no technique for reduction of thermal conductivity
29/09/2009 DOE TE Applications Workshop 30
Alkaline-Earth Hexaborides by M.Takeda (Nagaoka University of Technology)
200 400 600 800 1000 12000
-50
-100
-150
-200
-250
SrB6
CaB6
Ca:Sr=75:25 Ca:Sr=50:50 Ca:Sr=25:75 SrB6
(
V/K
)
Temperature (K)
CaB6
200 400 600 800 1000 1200
105
106
(1
/m
)
Temperature (K)
SrB6
CaB6
MB6
200 400 600 800 1000 12005
10
15
20
25
30 CaB6
Ca:Sr=75:25 Ca:Sr=50:50 Ca:Sr=25:75 SrB6
Ther
mal
Con
duct
ivity
, (W
/mK)
Temperature, T (K)
200 400 600 800 1000 12000.0
0.1
0.2
0.3
CaB6
Ca:Sr=75:25 Ca:Sr=50:50 Ca:Sr=25:75 SrB6
Figu
re o
f mer
it, Z
T (-
)Temperature, T (K)
Thermoelectric & Transport properties:To estimate the optimal electrical property for TE conversion
Synthesize (Ca,Sr)B6 alloys:To reduce thermal conductivity keeping high electrical
property by alloying
TE performance was successfully improved by alloying: the ZT=0.35 was obtained at 1073K.
By Solid Reaction &SPS
29/09/2009 DOE TE Applications Workshop 31
RuAl2RuAl2
: semimetal, Band Gap=0.1~0.6 eV
Ru-Al binary phase diagram
Orthorhombic TiSi2
type
Crystal structure of RuAl2
Decompose at 1363K
AlRu
RuA
l 2
*D. Mandrus, et al., Phys. Rev. B, 58 (1998) 3712.
The maximum ZT
was estimated to be ~0.6 at 700 K. The electrical properties were not optimized yet.
Thermoelectric properties of nondoped RuAl2
have been reported*.
29/09/2009 DOE TE Applications Workshop 3210.02.2009 32
Nanovoid forming effect
ZnAlO
VFA 3wt% 5wt% 10wt%
150nm
425nm
1800nm
Thermal conductivity reduced by 30-35% with forming nanovoid in ZnAlO system
ZT=0.54-0.59 at 1273K: nearly two times more than that of no nanovoid dispersion samples
29/09/2009 DOE TE Applications Workshop 3333
Nanophase separation effect for (MA0.5
,MB0.5
)NiSn System (MA,MB=Hf,Zr,Ti)
Nanophase separation is induced with the formation of solid solution for specified combination of MA and MB.
Samples are made by directional solidification.
n-type Half-Heusler
The results would be caused by a combined effect of phase separation and solid solution.
29/09/2009 DOE TE Applications Workshop 3434
Nanoparticle inclusion effect for filled skutterudites system
CeFe3
CoSb12
-MoO2
composite was made by the mechanical alloying and spark plasma sintering.
The ZT value increased from 1.1 to 1.22
at 773K.
29/09/2009 DOE TE Applications Workshop 35
Semimetal Ru1-x
Fex
Al2 by Prof. Yamanaka’s Group (Osaka Univ.)
300 400 500 600 700 800 900 10000.00
0.05
0.10
0.15
0.20
0.25
0.30
Dim
ensi
onle
ss fi
gure
of m
erit,
ZT
Temperature, T / K
RuAl2 Ru0.99Mn0.01Al2 Ru0.98Mn0.02Al2 Ru0.95Mn0.05Al2
300 400 500 600 700 800 900 10000.00
0.05
0.10
0.15
0.20
0.25
0.30
Dim
ensi
onle
ss fi
gure
of m
erit,
ZT
Temperature, T / K
RuAl2 RuAl1.98Si0.02
RuAl1.95Si0.05
RuAl1.90Si0.10
Mn doped
Si doped
.
The ZT
values were 0.17 (p-type) and 0.28 (n-type) at 900 K.
By Arc melting
p-type
n-type
29/09/2009 DOE TE Applications Workshop 36
Commercial TEG modules by KELK & Komatsu , and Yamaha as the outcome with JATeCS-project
Power density = 0.96 W/cm2
and 1.95 g/W based on formal module size
0.0%
1.0%
2.0%
3.0%
4.0%
5.0%
6.0%
7.0%
0 50 100 150 200
Tem perature differential, ΔT/K
Conversion efficinency, η
m/%
Module Efficiency =5.7% at ΔT=150K.