AFOSRAFOSR--MURI on Energy Harvesting and Storage Systems (EHSS)MURI on Energy Harvesting and Storage Systems (EHSS)

Period: May/2006-May/2011Funding: $6M

Dr. B. “Les” Lee (Air Force Office of Scientific Research), PMDr. Joan Fuller (Air Force Office of Scientific Research), Co-PMDr. Victor Giurgiutiu (Air Force Office of Scientific Research), Co-PM

Researchers: Minoru Taya, PI , UW

UW: Chunye Xu (ME), G. Cao(MSE), S. Jenekhe(ChemE), Y. Kuga(EE)

CU: M. Dunn, K. Maute, R. YangUCLA : T. Hahn, S JuVPI : D. Inman

Collaborating Industry, Boeing, etc.

Goal : To develop a set of energy harvesting materials and systems for future AF vehicles

Aug 25,2006

UW - Center for Intelligent Materials and Systems

Multi-scale approach to design ofenergy harvesting aircraft systems

a. system level

c. material level

micro-scale

antenna

PCB Power amplifier

TEC

Heat spreader

Polymer solar cells (PSC)

thermo-electric (TE)

antenna system under the wing with TE

Polymer matrix composite (PMC) cellBattery package layer (BPL)

separatorCathodeanode

Polymer solar cell

PMC BPL

macro-scale

nano-scale

d. nano-composite levelBinder polymerCarbon nano tube network

Porous Cu collector

p-type TEn-type TE

TEC

TIM

Thermal interface material (TIM)

b. component levelPolymer

battery cells

TECantenna

skin

PBC

Polymer solar cells

+

UW - Center for Intelligent Materials and Systems

A. Design Tools for Multifunctional Materials and Structures (Dunn, Maute and Taya)

B. Energy Harvesters based on thermoelectrics (Yang and Taya)

C. Energy harvester based on polymer solar cells (Jenekhe ,Xu, Nango)

D. Manufacturing and durability of energy harvesting structures(Ju and Hahn)

E. Design of Energy Storage System (Xu, Cao, Kuga)

F. Electric System Design (Kuga)

G. Multimode Energy Harvesting for ISR/MAV Missions (Inman)

H. Educational Programs (Taya and Dunn)

I. Validation of the Proposed EHSS (all)

MURI - EHSS Tasks

Tasks and MilestonesThe first 3 years The last 2 years Milestones and Deliverables

1st year 2nd year 3rd year 4th year 5thyear A Design Tool-component level A1 Electrochemo-mechanical coupling Model ▼ A2 Multi-scale, multi-physics constitutive Model ▼ A3 Design optimization model ▼ B TE energy harvester B1 Optimized TE materials ▼ B2 Processing of TE materials ▼ B3 Process TE unit ▼ B4 Process of TE models ▼ B5 Integration and testing with heat sources ▼ C Polymer solar cell harvester C1 Optimization of donor-acceptor copolymers by DFT ▼ C2 Process and characterization of molecular hetero junction PSC ▼ C3 Demo of PSC sheet with goal of 10% Efficiency ▼ C4 Process and demo of layer PSC About with 20% or more efficiency ▼ D Manufacturing and durability D1 Multifunctional manufacturing and integration schemes ▼ D2-1 Multifunctional characterization capability ▼ D2-2 Existing state-of-the art materials and material forms ▼ D2-3 1st generations of new materials ▼ D2-4 2nd generations of optimized new materials ▼ E Energy storage system E1 Cathode material system ▼ E2 Anodic material system ▼ E3 Environmentally storage electrolyte system ▼ E4 Demo of PBC ▼ E5 Demo of super capacity ▼ E6 Integration of PBC and PSC ▼F Electrical system design F1 Power conditioner ▼ F2 Hybrid power unit ▼ F3 Wireless system ▼ F4 Overall electrical system design ▼ G Multimode Energy Harvesting G1 System analysis of UAV ▼ G2 Design rules ▼ H Education Programs ▼ I Validations I1 components ▼ I2 UAV demonstrator ▼

MassDisplacementStressTemperature

Criteria

SQPMMASLP

Optimizer

DirectAdjointFD

Sensitivity

CurrentPower

2-D3-DHarmonic

Problem

CU – Multi-Physics Optimization Toolbox

GoldPolysiliconAluminum

MaterialMultiphysics

Thermo-mechanicalElectro-thermo-mechanical

piezo-electric

thermo-electric

system design

photovoltaic

component designphotovoltaic

storage

thermo-electric

antenna

skin

material design

collector

separator

+ electrode

- electrode

structure

• overall system design• placement of EHS systems• power storage management

• mechanical design• coupled analysis & design• integration

• structural battery design• multi-physics analysis

Electro-chemical-mech.

Computational Design Tool DevelopmentComputational Design Tool Development

Multiphysics Material & Micro Device DesignMultiphysics Material & Micro Device Design

Phononic Metamaterials DesignPhononic Metamaterials Design

Bandgap Metamaterials

Application-Specific Metamaterials

optimized material layout

wavefield in a the optimized material

surface wave guide

decomposed FE mesh

0

0.2

0.4

0.6

0.8

1

1.2

-0.2 0 0.2 0.4 0.6 0.8 1

κbb (1/mm)

κ aa

(1/m

m)

a a

b b

0

0.2

0.4

0.6

0.8

1

1.2

-0.2 0 0.2 0.4 0.6 0.8 1

κbb (1/mm)

κ aa

(1/m

m)

a a

b b

x

y

Photoelastic Metamaterials DesignPhotoelastic Metamaterials Design

uniaxial bending

ElectroElectro--Mechanical Microsystem DesignMechanical Microsystem Design

Design

Spa

ce

optimized gold pattern

Design

Space

optimized actuator

Design Tools for EH&S CompositesDesign Tools for EH&S Composites

MassDisplacementStressTemperature

Criteria

SQPMMASLP

Optimizer

DirectAdjointFD

Sensitivity

CurrentPower

2-D3-DHarmonic

Problem

CU - Topology Optimization Toolbox

GoldPolysiliconAluminum

MaterialMultiphysics

Thermo-mechanicalElectro-thermo-mechanical

Focus I: Design of Batteries with Load-Barring Capabilitiesmaximize energy storage & stiffness & strength

Collaboration with local companies & labs

ohmic load

Preliminary work: developed and implemented a micro-structural electrochemical-mechanical battery finite element model

Electro-chemo-mechanical

Design Tools for EH&S Enabled VehiclesDesign Tools for EH&S Enabled Vehicles

design with advanced EH&S materials

guidance for material &

device design

metamaterial design

system design system performancedemonstration and verification

component design

endu

ranc

e

range

application driven preference

component / material level criteria & parameter space

varia

ble

2

variable 1

crite

rion

2

criterion 1

system design space

Pareto optimal set

antennaPCB Power amplifier

TEC

Heat spreader

p-type TEn-type TE

TEC

TIM

Nanocomposites - Bulk Thermoelectric Materials with Embedded Nanostructures

• Cost-Effective• Mass Production• A Paradigm Shift on TE Research

Nanocomposite Thermoelectric Materials and Energy Harvesting System

Expectations• Reduced thermal conductivity.• Electrical conductivity comparable to or better than bulk.• Increased Seebeck Coefficient.• Overall Enhanced ZT by a factor of 2-5.

0.0

0.5

1.0

1.5

2.0

2.5

3.0

1940 1960 1980 2000 2020

FIG

UR

E O

F M

ERIT

(ZT)

max

YEAR

Bi2Te3 alloyPbTealloy

Si0.8Ge0.2 alloy

Skutterudites(JPL)

PbSeTe/PbTeQuantum-dotSuperlattices(Lincoln Lab)

Bi2Te3/Sb2Te3Superlattices(RTI)

AgPbmSbTe2+m(Kanatzidis)

Dresselhaus

State-of-the-art Thermoelectrics

Statement of the Work (TE)- Materials, Devices, & System

Schematic drawing of silicon-based TE device (Pick & Place process, TE legs are made of nanocomposites)

P leg

Silicon substrate

SU-8

Ti/Cu /solder paste

Metal Interconnection

N leg

• Design and characterize thermoelectric nanocomposites• Design of TE devices• Testing TE devices and system integration

CU-Tasks on Thermoelectrics

ThermocoupleLeadsHeater

Leads

Conventional Four-Probe method Sub-ps Pump-Probe method

UW tasks – Nanocomposite synthesis & Device Fabrication

1. Develop atomic simulation tools to study the thermal conductivity, Seebeckcoefficient and electrical conductivity of nanocompositesand design nanocomposites

with effective ZT = 1.5-4.

2. Develop tools to measure the thermoelectric properties of

nanocomposite sample made in UW.

3. Develop tools to design thermoelectric devices and to predict the performance of TE-subsystem in AF environments 4. Assist UW to develop the fabrication process for nanocomposite TE devices and test TE devices.

Fabrication process for nanocomposite TE devices

Si wafer

Photoresist mask

(a) Photoresist masking

(b) Deep RIE

(c) Photoresist masking on opposite side

(d) Deep RIE

(e) Filling TE materials into the mold

(f) Polishing

(g) Connecting the P-N elements

(h) Final assembling and Si mold removal

P-type TE powder

N-type TE powder

Metal electrode

Substrate

Capsule

Si wafer

Photoresist mask

(a) Photoresist masking

(b) Deep RIE

(c) Photoresist masking on opposite side

(d) Deep RIE

(e) Filling TE materials into the mold

(f) Polishing

(g) Connecting the P-N elements

(h) Final assembling and Si mold removal

P-type TE powder

N-type TE powder

Metal electrode

Substrate

Capsule

Microfabricationprocesses to make micro/mini TE devices with the use of mechanical alloyed nanocomposite powder

Ref. : J.F. Li et al.Sensors and Actuators A 108 (2003) 97-102.

Effic

iency

(%)

Universityof Maine

Boeing

Boeing

Boeing

BoeingARCO

NREL

Boeing

Euro-CIS

200019951990198519801975

NREL/Spectrolab

NRELNREL

JapanEnergy

Spire

No. CarolinaState University

Multijunction ConcentratorsThree-junction (2-terminal, monolithic)Two-junction (2-terminal, monolithic)

Crystalline Si CellsSingle crystalMulticrystallineThin Si

Thin Film TechnologiesCu(In,Ga)Se2CdTeAmorphous Si:H (stabilized)

Emerging PVDye cells Organic cells(various technologies)

Varian

RCA

Solarex

UNSW

UNSW

ARCO

UNSWUNSW

UNSWSpire Stanford

Westing-house

UNSWGeorgia TechGeorgia Tech Sharp

AstroPower

NREL

AstroPower

Spectrolab

NREL

Masushita

Monosolar Kodak

Kodak

AMETEK

Photon Energy

UniversitySo. Florida

NREL

NREL

NRELCu(In,Ga)Se2

14x concentration

NREL

United Solar

United Solar

RCA

RCARCA

RCA RCARCA

Spectrolab

Solarex12

8

4

0

16

20

24

28

32

36

University ofLausanne

University ofLausanne

2005

Kodak UCSBCambridge

NREL

UniversityLinz

Siemens

ECN,The Netherlands

Princeton

UC Berkeley

Taken from a presentation by Baldwin “Energy Efficiency and Renewable Energy; Energy: A 21st Century Perspective; National Academy of Engineering; June 2, 2005”

Best Research-Cell Efficiencies

Task on Energy Harvesters Based on Polymer Solar Cells1. Design and Synthesis of D-A Copolymers

• Band structure engineering by DFT• Visible-NIR absorption to match solar spectrum• High carrier mobilities

2. Fabrication and Evaluation of Solar Cells• Layered Heterojuction (LH)• Bulk Heterojuction (BH)

3. Synthesis and Evaluation of Molecular Heterojuction(MH) Cells

NN

S

NN

N

NN

x y

x y

RR

R Rn

n

x y n

S

R R

S

R R

S

R R

R R

S

NN

S

N NS

NN

S

N N

R R

R R

R R

R R

A-BlockD-Block

SS

SS

R1 R1

R1 R1

R1 R1

R1 R1

... ...

LUMO

HOMO

LUMO

HOMO

D-Block

A-Block

S

NN

nS

DFT calculation

4. Fabrication and Evaluation of Hybrid Organic / Inorganic Solar Cells

5. Integration of Polymer Solar Cells with Other EHSS Components

Solar Spectrum

Nature: Purple Photosynthetic Bacteria

The antenna complexes efficiently realize various photosynthetic functions due to the presence of cofactors (BChl a and carotenoid) assembled into the apoproteins.

Photosynthetic Bacteria

AFM image of the LH1 complex on mica.

LH1-RC

e-

ITO

Bio-inspired Design of Dye-sensitized Solar Cell (DSSC)

NanotubeNano particles

TiO2

Dye

Ru complex Phthalocyanine

NH N

N HN

H

OOH

H

O

Chlorophyll

Redox, Electrolyte

Counter

LiI, CuI, KI,Ionic liquids,Solid Electrolyte

Pt, Au, C60, Carbon nanotubeFilm (PET, PEN)

Dye1 Dye2 Dye3

Energy harvesting and storage system-Development of efficient electrode and electrolyte for battery, supercapacitor and dye-sensitized solar cells

separator

cathode

anode

Lithium polymer battery (LPB)

Top

polymer matrix composite (PMC)

battery packaging layer (PBL)

mesoporous V2O5 •Li V3O8

porous Al current collector grid (+)

mesoporous polyolefin

Lithium polymer gel electrolyte

porous Cu current collector grid (-)

carbon nanotube anode

PBL

PMC

polymer solar cell

PolypropyleneAluminum

Toughened epoxy

Polypropylene

AluminumToughened epoxy

Toughened epoxy toughened epoxy adhesive layer for strong bonding

mesoporous polyolefin

parallel or series connected PBCs

Development of thin film lithium battery for energy storage from polymer solar cell

External Quantum Efficiency of Solar Cell

5-10%

Wing area of UAV 10.9 m2

Solar Energy at 50000 ft

~20 kWhm2/day

PSV harvested Electrical Energy

21.8 kWh/day

Battery Weight to store 2/3 of the energy for night fly

23.8 kg

D-A copolymer solar cell

Al current collector (+)

PET

mesoporousCarbon anode

mesoporousInsulator layerelectrolyte

Cu current collector (-)

mesoporous V2O5or MnO2, etc.

I

Battery goal: 600 Wh/kg

ITO nanorod

Cao’s research 1: Nanostructured Li battery electrodes

0.01 0.1 1 10 100 10001

10

100

1000

10000

100000

1000000

1E7

Spec

ific

Pow

er (W

/kg)

Specific Energy (Wh/kg)

Capacitor

ElectrochemicalCapacitor

BatteriesFuel Cell

0.01 0.1 1 10 100 10001

10

100

1000

10000

100000

1000000

1E7

Spec

ific

Pow

er (W

/kg)

Specific Energy (Wh/kg)

Capacitor

ElectrochemicalCapacitor

BatteriesFuel Cell

Capacitor

ElectrochemicalCapacitor

BatteriesFuel Cell

Ideal performance:

Large storage capacity: energy

Fast transport kinetics: power

UCLA Task

• Goal– Develop multifunctional design and

manufacturing methodologies for energy harvesting and storage structures.

AC Propulsion’s SoLong UAV

Multifunctional Characterization of Batteries and Thermoelectrics

• Mechanical Properties– Modulus, strength– Stress-strain relations– Failure mechanisms

• Interaction Between Performance and:– Deformation– Pressure– Temperature

Cathode

1/8” HD Rubber

Anode

Load

Cathode

1/8” HD Rubber

Anode

Load

1/8” HD Rubber

Anode

Load

1/8” HD Rubber

Anode

Load

Structural Integration of Batteries and Thermoelectrics

• Structural integration methods– Prepreg lay-up– Resin transfer molding

• Performance of integrated structures– Performance under

loading– Microstructure

analysis

Resin Resin

Vacuum 28” Hg

Photovoltaic Film

Thermal Collector

Composite Laminate

Thin Film Battery

Thermoelectric Fiber

Electric Wiring Not Shown Photovoltaic Film

Thermal Collector

Composite Laminate

Thin Film Battery

Thermoelectric Fiber

Electric Wiring Not Shown

H A Sodano

• Tasks included determining:– Available sources– Placement criteria– Key parameters– Design rules– Storage and power

management– Experimental

verification– Transitions to DOD

Design Rules for Multimode Harvesting

Formulate analysis tools for hybrid harvesting and storage

MAV Wing Cross Section

D. J. Inman

Electric System Design Using Supercapacitors and Battery

Goals-Integration of energy harvesting devices into electrical system.-Study of energy efficiency and how to improve it.-Initial design will be conducted with currently available energy harvesting devices including thermoelectric devices, photo-cells and super-capacitors.

Simplified diagram of the electrical system

MURI Collaboration Team