DoD End User Perspective and DARPA Palm Power Program

DOE Fuel Cell Portable Power WorkshopJanuary 15-17, 2002

Phoenix, Arizona

Dr. Robert NowakDr. Robert NowakDARPA Defense Sciences OfficeDARPA Defense Sciences Officernowak@darpa.milrnowak@darpa.mil 703 696703 696--74917491

Dr. Karen Swider LyonsDr. Karen Swider LyonsNaval Research LabNaval Research Lab

Advanced Energy TechnologiesAdvanced Energy Technologies

DoD Compact Fuel Cell Evolution

1996 - H2 System (metal hydride)• 40 W / 90 Wh; 1.6 kg

1992 –H2 Stack• 15 W; 2.3 kg

1998 - H2 System (compressed hydrogen• 50 W/ 2 kW-hr; 3.4 kg

2001 – DMFC - System• 60 W; 6.8 kg; 30% efficiency SOFC –Hydrocarbon – System

• 20 W; 0.72 kg; 28% efficiency (Goals)“It’s the fuel stupid!”“It’s the fuel stupid!”

The Future?

Marine Corps Air Ground Combat Center29 Palms, CA, Fall 1999

MILITARY EXERCISETRAINING

Fuel Cells aboard Humvee

PRC-119 Radios

Retransmission Site

COST ESTIMATE FOR ONE RETRANS SITE

• BA5590 BATTERIES = $8000• FUEL CELLS = $250

Ball Aerospace & Technologies Corpand H-Power Corp

• Operates directly on methanol (no fuel processing required)• Very low temperature operation (case and cooling air is cool to the touch)• One gallon of methanol ( < $0.50) equivalent to 100 lbs. batteries ($4000)• Technology easily scaled – cellular telephones (1 Watt on up)• Several distributed units could replace unreliable, noisy generators• Future technology goal - operate on logistics fuels

Direct Methanol Fuel Cell

60 Watt Packaged System

LANL and Ball Aerospace & Technologies Corporation

Brassboard

Direct Methanol Fuel Cells for Cellular Phones

•One Month Operation?•No Battery Chargers•Scaleable Technology for More Power Hungry Devices

PolyFuel

NEC

Motorola

Manhattan Scientifics

Performance Shortfall of Today’s Portable Power Sources for DoD Applications

1600 2000 4000 60000 200 400 600 800 1000 1200 14000

100

200

300

400

500

600Micro Air Vehicles

Robots

Micro ClimateCooling

Exoskeletons

Soldier Power

2005

Specific Energy, Whr/kg

Spec

ific

Pow

er, W

/kg

Batteries

2018-252008

! Develop a 20 W power source in a hand-held package having 15 times the energy content of the best battery to meet future power requirements in 2010 and beyond

Idea:

Technical Challenges:

Impact:Highlights:

! For…Objective Force Warrior, SOCOM

! To…Enable Future Missions! via…Energy Conversion of High

Energy Fuels! Scale Up Option for Cooling, EXO,

etc.

" New Start in FY01; Five Year Program. Phase I – 3 Years

" Multidisciplinary teams: Large Corporations, Small Businesses, Universities, Non-profits

" Transition Partners: PM Soldier, Natick, CECOM, SOCOM, Marine Corps, Navy

! Highly efficient energy conversion ofliquid fuels

! New materials for thermal management, catalysis! Novel fabrication tools for highly compact, complex

systems

Palm PowerResource Allocation

Materials8% Materials

Processing6%

Components25%

Systems61%

10

100

1,000

10,000

0 50 100 150 200 250

Syst

em S

peci

fic E

nerg

y, W

h/kg

Discharge Time at 20W, hours

3 Hours 3 days 10 days

2,000 Wh/kg goal for 3 day system 3,000 Wh/kg goal for 10 day system

1,000 Wh/kg goal for 3 hour system

Current SOA Batteries (Primary & Secondary)

HighSpecific

Power

HighSpecificEnergy

Mission Energy Goals

Program StructureMaterials (8%)! Membranes

" U of Colorado! Electroactive Polymers

" SRI! Thermionics

" Vanderbuilt" ENECO

! Thermophotovoltaics" Draper Laboratory

! Thermoelectrics" RTI

Materials Processing (6%)! Ceramic Extrusion

" Georgia Tech" Adaptive Materials

Components (25%)!Small Engine

" U of Michigan! AMTEC

" AMPS! Micro Fuel Processing

" RTI" Altex

! SOFC" MSRI

! Combustion" Yale U

Integrated Systems (61%)! DMFC

" Ball Aerospace" Creare

! SOFC" ITN Energy Systems" Honeywell/General Electric

Program Philosophy• Multiple Technologies• Cross-fertilization of Materials andComponents

• Flexible Integration Into Systems

AlN

Si

Thin-filmTE AlN

Si

MicroChannelsfor Heat-TransferFluids

20 µµµµm

YSZElectrolyte

NI-YSZAnode

Anode Supported Tubule(SEM Fracture Surface)

Approach:• Steam reforming of hydrocarbon fuels

and thermal decomposition of ammonia in a H2 selective membrane reactor

• Integrated micro-channel reactor, auxiliary fuel combustor, H2membrane, gas/gas heat exchanger heat recovery, and insulation panels for low heat loss.

• Maximized thermal efficiency and hydrogen yield

• Integrated Micro-channel reactor/ combustor for hydrogen generation by thermal decomposition of NH3

• High-flux, high-selectivity Pd-based composite membranes

• Micro-channel gas/gas heat exchangers for high thermal efficiency

• “Additive” manufacturing for light-weight fuel processor components

Status of Current Technologies:

• To develop lightweight, fuel processors to convert liquid logistic fuels to high purity on-demand hydrogen

Overall Objective:

Compact Integrated Multi-Fuel ProcessorsAshok S. Damle, Research Triangle Institute

Charles J. Call, MesoSystems Technology, Inc.

Hydrogen Generator Targets:• Capacity - 1.5 to 5 kW-hr• Specific Energy - 2 to 3 kWh/kg

Conceptual NH3-based Hydrogen Generator

Valve

Reactor andHeat Exchanger Butane

Canister

AmmoniaAdsorbentCanister

AmmoniaTank

11.5 cm

8.5 cm

20 cm

Proposed SOFC Palm Power System

Thermal ManagementAir Delivery

Fuel Delivery

CPOXfor startup(pre-reformingif necessary)

High Performance

Direct OxidationSOFC

Exhaust

• Power: 20 W, 12 VDC• Estimated dimension: 8.5 x 11.5 x 20 cm (10-day

mission)• Estimated weight (excluding fuel): 0.5 kg• Estimated energy density (JP-8 fuel):

• 2000 Wh/kg (3-day mission)• 3700 Wh/kg (10-day mission)

• Fuel: JP-8Honeywell/GE

Honeywell/GE SOFC Performance

0

0.2

0.4

0.6

0.8

1

1.2

1.4

0 0.5 1 1.5 2 2.5

Current Density (A/cm²)

Volta

ge (V

)

0

0.2

0.4

0.6

0.8

1

1.2

1.4

Pow

er D

ensi

ty (W

/cm

²)

Voltage in Syngas

Power Density in Syngas19% H2, 24% CO, 1% CO2, Bal N2

Power Density in H2

Voltage in H2 • 800°C operation• Open circuit voltages in

agreement with theoretical values

• Peak power density:– 1.3 W/cm² in

hydrogen– 0.85 W/cm² in JP-8

syngas

0.0

0.2

0.4

0.6

0.0

0.2

0.4

0.6

Diesel

Toluene

Decane

0.0

0.2

0.4

0.6

0.0

0.2

0.4

0.6

Volta

ge (V

)

Cur

rent

den

sity

(A/c

m2 )

0 2 4 6 8 10 120.0

0.2

0.4

0.6

0.0

0.2

0.4

0.6

Time(hr)

Direct Oxidation of Liquid Hydrocarbons

• Performance on liquid hydrocarbon fuels at 700°C

• Stable operation

Gorte, Vohs, Worrell

Direct Oxidation ofHydrocarbons in SOFCs

Diesel – Performance vs. Time

0.0 0.2 0.4 0.6 0.80.0

0.2

0.4

0.6

0.8

1.0

Pow

er D

ensi

ty (W

/cm

2 )

Volta

ge (V

)

Current Density (A/cm2)

0.00

0.05

0.10

0.15

0.20

I-V for Diesel Fuel at 700°C

0 2 4 6 8 10 120.0

0.2

0.4

0.6

0.8

1.0

Voltage Current Density

Volta

ge (V

) and

Cur

rent

Den

sity

(A/c

m2 )

Time (hr)

Gorte, Vohs, Worrell

CPOX for Processing Hydrocarbon Fuels

• Fuels: propane, butane, octane, JP-8, and diesel

• Duration: 700 hours to date

• Thermal cycles: 10

• Sulfur tolerance: 1000 ppm dibenzothiophenein JP-8

• Yield: 70-80% of LHV in JP-8

0%

20%

40%

60%

80%

100%

0 40 80 120 160 200 240 280 320

Time (Hours)

Perc

ent Y

ield

%

H2

COThermal Cycle

Honeywell/GE

GOAL: 20 W power source in a hand-held package having 15 times the energy content of the best battery

http://www.darpa.mil/dso/thrust/md/palmpower/index.html