CAM
Center for Advanced Materials
University of Houston
NASA Research Partnership Center
Thin Film Fuel Cells and Hydrogen
Storage Materials for Solar Energy
Application
Alex Ignatiev1,2, Ainur Issova2, Mukhtar Eleuov2
1
Center for Advanced Materials
University of Houston,
Houston, TX 77204-5004
2
Institute for Physics and Technology
Almaty, Kazakhstan
Almaty, 2011
Center for Advanced Materials
University of Houston
NASA Research Partnership Center
Solar Energy Utilization
• Sunlight Required
• Energy Storage Needed
for Nighttime and Cloudy Operation
• Store Energy in Hydrogen..
• Electrolyze Water
• Utilize Hydrogen Fuel Efficiently
CAM
Center for Advanced Materials
University of Houston
NASA Research Partnership Center
Hydrogen Storage Options
• Liquid
• Cold – 22K
• 5 wt% - Adequate
• EXPENSIVE…..
• Gas
• High Pressure- 200-500 bar
• 2-3 wt% - Too Little Hydrogen
• High Pressure Danger
• Hydrides
• ~ 1 wt% - Too Little Hydrogen in Cycle
CAM
Center for Advanced Materials
University of Houston
NASA Research Partnership Center
CAM
Volume for Storage of 5 kg H2 in Different States
(Equivalent to 20 L Gasoline)
No Effective way of Storing Hydrogen…..
• Polymer Nanostructures…. ??
CAM
Center for Advanced Materials
University of Houston
NASA Research Partnership Center
Nanostructured Polymers
• Polyanaline Nanotubes
• Conducting Polymers
• Nanotube pores
• High surface area
Polyaniline
H
N
H
N
H
N
n
Polyaniline Nanotubes
CAM
Center for Advanced Materials
University of Houston
NASA Research Partnership Center
Polyaniline (PANI) Charge & Discharge
• Charge at 300psi for
2 hours
Torr
• Multiple Charge –
Discharge Cycles
Charged A
-6
• Mass Spectrometer
Read-out
• PANI  2.5-3 wt% H2 Uptake
1.2x10
-6
1.1x10
-6
1.0x10
-7
9.0x10
-7
8.0x10
-7
7.0x10
-7
6.0x10
-7
5.0x10
-7
4.0x10
-7
3.0x10
-7
2.0x10
-7
1.0x10
0.0
•Tested to 12+ Cycles-no deg
Charged B
Charged E
Charged D
Discharged B
Discharged E
Discharged A
Discharged D
20
40
• Good Hydrogen Storage and Cycling
60
80
o
Temp. C
100
120
140
Center for Advanced Materials
University of Houston
NASA Research Partnership Center
CAM
Volume for Storage of 5 kg H2 in Different States
(Equivalent to 20 L Gasoline)
Polyaniline
Polyaniline - Promising Hydrogen Storage System
Center for Advanced Materials
University of Houston
NASA Research Partnership Center
Efficient Use of Hydrogen Fuel
Hydrogen for Transportation
• Internal Combustion Engine
• Not Use – Explosive Reaction
• Still form NOx
• Use Fuel Cell
• Electrochemical Reaction
• OK - No NOx formed…..
• Only WATER….
CAM
CAM
Center for Advanced Materials
University of Houston
NASA Research Partnership Center
What is a Fuel Cell?
A device that generates electricity by combining
fuel and oxygen in an electrochemical reaction.
2e-
H2O
Anode
O2-
Electrolyte
O2-
Cathode
O2-
-
H2 Fuel
2e
Advantages
1/ O Oxidant
2 2
• High energy conversion efficiency
• Minimal environmental impact
• Stackable to reach very high power output
• Reduced noise level
Center for Advanced Materials
University of Houston
NASA Research Partnership Center
Solid Oxide Fuel Cell
• Hydrogen and oxygen reactants
• ZrO3 electrolyte
• Nickel anode
• Operating temperature is 900-1000°C
• Encapsulation materials challenges
• High materials costs
• High market cost
But, High Efficiency > 60%
• How to Reduce market cost …. ??
CAM
Center for Advanced Materials
University of Houston
NASA Research Partnership Center
CAM
Apply Thin Film Materials Expertise to SOFC Challenges
• Develop New Design: Thin Film Solid Oxide Fuel Cell
• Thin Film Heterostructure Design
- Thin electrolyte- lower temperature operation
- Atomically ordered films/interfaces- lower resistance
• Microelectronics Processing - Economies of Scale
• Lower Fabrication Cost
• Smaller Size
• Lower Cost
Center for Advanced Materials
University of Houston
NASA Research Partnership Center
CAM
Thin Film SOFC Heterostructure Growth
• Thin Film Atomically Ordered YSZ Electrolyte
• Reduce Internal Defects
• Reduce Interface Defects
• Pulsed Laser Deposition of Epitaxial YSZ Film
on Crystalline Nickel Foil Substrate
Epitaxial
Growth
Center for Advanced Materials
University of Houston
NASA Research Partnership Center
CAM
Thin Film Heterostructure Solid Oxide Fuel Cell
Fuel
Ni Foil Anode NOT Porous
Nickel Anode
~20mm thick
Yttria Stabilized Zirconia
Thin Film Electrolyte
~ 0.1 - 1 mm thick
Oxygen/Air
Total Cell Thickness
~ 20-25 mm thick
Porous LaSrCoO3 Cathode
~ 1 mm thick
Center for Advanced Materials
University of Houston
NASA Research Partnership Center
CAM
Ni Porosity - Microelectronics Photolithography / Etching
• Electrochemically Etched Nickel Anode
• 60 mm Etched Pores
•Nickel Side Electro-etch
CAM
Center for Advanced Materials
University of Houston
NASA Research Partnership Center
Thin Film Micro SOFC
1.0
120
110
100
0.8
o
570 C
90
o
V (V)
70
60
50
0.4
2
0.6
P (mW/cm )
80
555 C
40
o
520 C
30
0.2
20
o
480 C
10
0.0
0
0
5
10
15
20
25
30
35
I (mA)
TFSOFC I vs. V as a Function of Temperature
Hydrogen / Air - Polycrystalline Single Cell
Center for Advanced Materials
University of Houston
NASA Research Partnership Center
CAM
Thin Film Heterostructure SOFC Advancement
• Solid Oxide Fuel Cells Have Nickel Anodes
• Nickel Excellent Catalyst for Hydrocarbon Reduction
• BUT…….‘Coking’ at High Temperatures…. > 600 C
• However… Micro Fuel Cell Operates at 500 C – NO Coking…!
• Hydrocarbon Fuel Operation at ~60% Efficiency….
• Methane/Methanol
• Ethane/Ethanol
Center for Advanced Materials
University of Houston
NASA Research Partnership Center
CAM
Thin Film Fuel Cell Stack
• Require ~ 100V to 200V Operation
• Series Connection of Cell Elements
• Interconnect Required
• Stack Individual Cells Together in Series
• Work in Collaboration with Institute for Physics
and Technology, Almaty
• Advance Technology
• Finalize Product
•Technology Transfer
• Economic Growth
CAM
Center for Advanced Materials
University of Houston
NASA Research Partnership Center
Thin Film Fuel Cell Stack Components
Cell Element
Interconnect
Fuel
Flow
Oxidant
Flow
CAM
Center for Advanced Materials
University of Houston
NASA Research Partnership Center
Thin Film Heterostructure SOFC Advancement
Fuel Cell Stack Design
(In Progress)
cathode
electrolyte
anode
TFSOFC
Micro-patterned
Interconnect
Fuel flow
Oxidant flow
Projected > 5W/cm3 at ~500oC
CAM
Center for Advanced Materials
University of Houston
NASA Research Partnership Center
Summary
• A New Thin Film Solid Oxide Fuel Cell Design
• Efficient, Clean, Compact and Cost Efficient
• Low Temperature Operation
• Direct Use of Hydrocarbon Fuel
• Natural Gas
• Hydrogen from Dissociation of Water…????
Strategy for Efficient, Clean Electrical Energy
Generation
Automotive Energy
Distributed Energy