Development of a 5 kW Prototype Coal-based Fuel Cell

Steven S. C. Chuang The University of Akron

May 15, 2007Project ID #FCP9

This presentation does not contain any proprietary, confidential, or otherwise restricted information

2

Overview

• Project start date: 6/01/2006• Project end date: 5/31/2008• Percent complete: 46%

• Barriers addressed– Long term catalyst

durability– System thermal

management

• Total project funding– DOE share: $495,000– Contractor share: $178,654

• Funding received in FY06$323,538

• Funding for FY07$171,462

Budget

Timeline Barriers

• Bob Brown, The Ohio Coal Development Office

Partners

3

Objectives

• Overall: Design a 5 kW prototype coal-based fuel cell and fabricate a small scale coal fuel cell system including coal injection and fly ash removal ports.

• 2006: – Improvement of the anode catalyst structure and

the interface between electrodes – Development of fuel cell fabrication techniques

• 2007: Fabricate and test a small scale coal fuel cell system.

4

Approach• Improvement of the anode catalyst structure and

the interface between electrode and membrane. • Refinement of the techniques for fabrication of

the fuel cell assembly • Selection and testing of interconnect materials

for the coal-based fuel cell. • Investigation of the design factors for the coal

injection and fly ash removal systems. • Design and fabrication of a small scale coal fuel

cell system.

5

Technical Accomplishments/ Progress/Results

• Successful fabrication of the fuel cell assembly with a diameter greater than 1”.

• Identification of the active anode catalyst components for the electrochemical oxidation of coal and coke at temperature below 800 oC.

• Design and fabrication of coal fuel cell testing systems.

• Preliminary development of sulfur tolerant anode catalysts

6

PROXIMATE ANALYSIS ULTIMATE ANALYSIS

% Moisture as received 4.15 % Carbon 83.99

Dry % ash 4.80 % Hydrogen 5.50

Dry % volatile matter 37.98 % Nitrogen 1.88

Dry % fixed carbon 57.22 % Oxygen 8.63

SULFUR FORMS

% Pyritic 0.70 % Organic 1.21

% Sulfate 0.01 % Total 1.92

CALORIC VALUE (BTU/lb) 14258

EQULIBIRUM MOISTURE (%) 7.98

Ohio Coal # 5

7

200 nm

400 nm

200 nm

Coke before reaction

Coke after reaction

Fly ash after reaction

Coke and fly ash after the SOFC reaction in the reactor

8

0

0.2

0.4

0.6

0.8

1

1.2

0 50 100 150

Volta

ge (V

)

Coal Fuel Cell

Methane Fuel Cell

Comparison of IV curves for Cu Anode SOFC at 900 oC

Current density (mA/cm2)

“Coal-based Fuel Cell,” S. S. C. Chuang, PCT Int. Appl. (2006) (i.e., European Patent Application), 35 pp. CODEN: PIXXD2 WO 2006028502 A2 20060316; U.S. Patent Application; India Patent Application.

9

Fuel cell performance at 800 oCAnode: oxide; Fuel: 3 g of Ohio No. 5 coal

185 190 195 200 205 210 2150.00

0.25

0.50

0.75

1.00

1.25

1.50

1.75

2.00

-300

-200

-100

0

100

200

300

Cur

rent

(mA

)

Vol

tage

(V)

Time(min)

10

Fuel cell performance at 750 oCAnode: oxide, Fuel: 0.5 g of Ohio No. 5 Coal

0 10 20 30 400.0

0.1

0.2

0.3

0.4

0.5

0.6

0

20

40

60

80

100

Cur

rent

(mA

)

Vol

tage

(V)

Time (min)

11

SOFC Performance

•Stable, Sulfur tolerant and Carbon resistant catalyst

•Novel method to deposit the metal on anode

•Formation of carbon fiber network by metal catalyzed reforming of heptaneimproved the current collection ability.

0

0.2

0.4

0.6

0.8

1

1.2

0 100 200 300 400 500 600 700

Vol

tage

(V)

Current Density (mA/cm2)

Natural Gast=0 hrs, 800°CNatural Gas

t=24 hrs, 800 °C

H2t=0 hrs, 800 °C

H2t=24 hrs, 800 °C

M1-M2-YSZ/M-YSZ/YSZ/LSM-YSZ/LSMPrepared by Tape Casting Method

0

0.2

0.4

0.6

0.8

1

1.2

0 50 100 150 200 250 300 350

Vol

tage

(V)

Current (mA/cm2)

He(25%)/H2(70.35%)/C7H16(4.35%)(t+30)

He(25%)/H2(70.35%)/C7H16(4.35%)(t)

He(25%)/H2(75%)

Anode : M(5wt%)/YSZ Fibers(75%)/YSZ Powder(25%)Electrolyte : YSZ (0.3 mm)

Cathode : LSMO/YSZ Powder

12

Future Work• Selection and testing of low cost interconnect materials

for the coal-based fuel cell. • Investigation of the design factors for the coal injection

and fly ash removal systems. • Design, fabrication, and test of a small scale coal fuel

cell system • key milestones:

– Identification and successful development of an interconnects which cost less 50% of the present interconnects.

– Development of a fundamental understanding of the migration of the fly ash particles on the anode catalyst surface.

– Design and fabrication of a lab-scale of the coal fuel cell system.

13

Summary 1

• Relevance: Development of an effective anode catalyst to catalyze the electrochemical oxidation of coal/coke at 750 oC will allow the use of low cost materials for the construction of the fuel cell system.

• Approach: Identification and test of the low cost anode catalysts, interconnect, fuel cell housing materials for the design and fabrication of the coal fuel cell system.

14

Summary:2 • Technical Achievements:

– Fly ash produced from coal does not adhere to the anode catalystsurface.

– Current density of more than 80 mA/cm2 at 0.4 V has been achieved on an oxide anode catalyst at 750 oC.

– Technique for the fabrication of the fuel cell with a diameter greater than 1 inch has been developed.

• Technology Transfer/Collaboration:– Patent applications in progress– Collaboration with the Ohio Coal Development Office

• Proposed Future Research:– Development of low cost interconnects.– Determination of the key factors controlling the removal of fly ash.– Design, fabrication, and test of a small scale coal fuel cell system