FC Workshop 2015

Fuel cell systems for aircraft applications

S. Flade, T. Stephan, C. Werner, L. Busemeyer, J. Schirmer & J. Kallo

German Aerospace Center - Institute of Engineering ThermodynamicsUniversity of Ulm - Instiute of Energy Conversion and Energy Storage

Lampoldshausen, 15.09.2015

Aerospace Research Center and Space Agency ofthe Federal Republic of Germany (DLR)

• 7.700 employees• 16 national facilities• > 30 institutes and test facilities• offices in Brüssel, Paris, Washington• Test facilities in Almeria/Spain

• ESI Energy System Integration, DLR• Battery Systems and degradation• Fuel Cell Systems and degradation• Aircraft Applications MEA and AEA

Cologne

Oberpfaffenhofen

Braunschweig

Goettingen

Berlin

Bonn

Neustrelitz

Weilheim

Bremen Trauen

Lampoldshausen

Stuttgart

Stade

Augsburg

Hamburg

Juelich

Ulm

University of Ulm –Institute of Energy Conversion and Energy Storage

Department of Hybrid Concepts• Power Electronic Hardware, Controls and

FC/Battery Power Management Systems

Department of Propulsion Research• High power E-Machines, Generators

Applications: Aircraft applications, ….

Hardware/Teststand: • ICE-Battery-E-Machine Hybrid up to 250kW• Hydrogen infrastructure• Low Pressure and Temperature chamber for

components and complete systems

Cologne

Oberpfaffenhofen

Braunschweig

Goettingen

Berlin

Bonn

Neustrelitz

Weilheim

Bremen Trauen

Lampoldshausen

Stuttgart

Stade

Augsburg

Hamburg

Juelich

Ulm

• electric energy supply

• emmission free ground operation→ Autonomous Taxiing

• electric Main Engine Start

• supply of air conditioning

• water production(potable water and lavatory)

• waste heat recovery(de-icing, warm water generation)

• prevention and suppression of fire and explosions(tank inerting, cargo inerting)

• humidification of Cockpit air and/orcabin air

tank inerting

water generation

supply of thepower grid

De-icing of the wings

humidification (air)

emission freetaxiing

Electricengine startup

supply of airconditioning

Potentials of fuel cells in aviation applications→ Multifunctional use of fuel cell systems in an aircraft

Fuel Cell Aircraft and Airport Applications at DLRInstitute of Engineering Thermodynamics

Fuel Cell TechnologyDevelopment Platform

Electric Energy, ODA,  Water Source (MFFC)Energy Source for Emission Free Taxi

Modular Hybrid Development PlatformEASA CS.22 and CS.23.Light 

Flying Testrig for Fuel Cells and Hybrids,Emission Free Propulsionfor UAV and General Aviation(4‐6 Pax or 200 kg Payload)

Aircraft flight profile

Taxiing & Takeoff

Climb Landing & TaxiingCruise

Descent

0,25bar < Pin_air < 1bar

)()(

)()1(

)(21,0

__

__

_

_

__

__

2

2

2

2

2

2

InInOHSatInIn

InInOHSatIn

InOHIn

InOH

ExhaustExhaustOHSatExhaustExhaust

ExhaustExhaustExhaustOHSatExhaustCathode TprHp

TprHpp

pwith

TprHppTprH

gasinlet cathode of pressurer Water vapo

gasexhaust cathode of Pressure

gasinlet cathode of Pressure

gasinlet cathode ofhumidity Relative

gasexhaust cathode ofhumidity Relative

_2

InOH

Exhaust

In

In

Exhaust

p

p

p

rH

rH

gas exhaust cathode of eTemperatur

gas inlet cathode of eTemperatur

gas exhaust cathode of pressure vapor Saturation

gas inlet cathode of pressure vapor Saturation

__

__

2

2

Exhaust

In

ExhaustOHSat

InOHSat

T

T

p

p

Assumptions:• Pressure difference between cathode inlet and outlet is neglected• Water drag between cathode and anode is neglected• O2 – Concentration of cathode inlet gas is assumend to be 21 Vol.-%• Tin = TExhaust – 10K

Impact of feed gas humidification to the water manage-ment of a PEMFC under aviation relevant conditions

Impact of aviation relevant operating parameters to thewater management of a self-humidified PEMFC

System temperature control crucial for humidification

System build up:Fuel Cell Technology Transfer to Aircraft Application

Mechanical Strenght SimulationVibration, EMC, H2 Safety, Controls

Aircraft Application (DO16xX)Functionality, Architecture, BOP

FC System from Transport Application

Airworthy technology development platform

- Fuel cell- DC/DC- hydrogen storage

Fuel cell system efficiency as a function ofcathode inlet pressure and relative humidity at thecathode outlet

Temperature(cath out)

rHout (%) 950 mbar rHout (%) 700 mbar

45 161 10848 139 9355 98 6565 62 41

System efficiency

55°C

45°C

65°C

Adequate system temperature for optimal system efficiency (IStack = 0,5 Imax)

Fuel Cell System TopologyElectrical power assessment A320 (681 flights, 5 different A320)

Average real world consumptionlower than 50% of ELA

Electrical power data catalogue A320Profiles electrical power

• 681 Flights

• Flightphase definitionbased on ELA

Mission duration catalogue

Overall Electrical power catalogue

Average mission duration: ca. 100min Average electrical power: ca. 36kW

Average 3,6kg H2 /mission(at 50% system efficiency)

Specific electric power distribution and dynamics A320

Electric power and electric power dynamics • Power slopes up to +/- 50kW/s

• Minor absolute power case > 50kW

Hybrid System

Customized hybrid system for A320

Electric power and electric power dynamics Hybrid System – 50 KW FC

Hard boundaries FC dynamics 1kW/s power slope

Expected power from fuel cell system? Power and capacity of used battery ?

FC Hybrid system impact on battery power

A/C Power, fuel cell and battery power profile FC Hybrid System - 50 KW - 1kW/s

Battery power: + 75kW ; - 35kW

0,8kWh - capacity-35kW +75kW

Battery power

Fuel cell power

FC Hybrid System impact on battery capacity

Max power fuel cell (kW)

0,85kWh capacity

FC Hybrid System - 50 KW - 1kW/s

Battery power: + 75kW ; - 35kW Battery capacity: 0,85kWh (7kg)

Battery capacity as a function ofmax. FC system power

Bat

tery

capa

city

(kW

h)

Standard 09_2010

Folie 20

Abschätzung der idealerweise verfügbaren C-Rate

1. ∙ , ∙ ∙

2. , ∙ , ∙ ∙

3. , , ∙

4. , , , ,∙ ,

0

50

100

150

200

250

300

350

0123456789

40 45 50 55 60

Min

imum

, opt

imal

eC

-Rat

e [1

/h]

Ener

giei

nhal

t der

Bat

terie

[kW

h]

Begrenzung BZ Leistung [kW]

Energieinhalt derBatterieOptimale Entladerate

Optimale Laderate

-60

-40

-20

0

20

40

60

80

40 45 50 55 60

Bat

terie

leis

tung

[kW

]

Begrenzung BZ Leistung [kW]

max. Leistung

min. Leistung

max. Leistung OhneBegrenzung

-9-8-7-6-5-4-3-2-101

40 45 50 55 60

Bat

terie

ener

giei

nhal

t[kW

h]

Begrenzung BZ Leistung [kW]

max. Speicherstand

min. Speicherstand

max. Speicherstand OhneBegr.

0,85kWh42C 80C

Thank you for your attention!

Contact: josef.kallo@dlr.de