Transcript Oral Presentation 4

Calvin College
Engineering Senior Design
Team 10
April 24, 2008
Outline
 Introduction
 Microbial Fuel Cells
 Regulation
 Monitoring
 Feeding / Case
Team 10: Members
Jared Huffman
Brianna Bultema
Achyut Schrestha
Chris Michaels
Why Biobattery?
 Problems of Conventional Batteries
 “Hard to Do”
 Interdisciplinary Talents
Introduction
Microbial Fuel Cells
Regulation
Monitoring
Feeding/Case
Design Goals
 USB Power output
 5V, 5% tolerance
 0.1-0.5A
 Refillable Food Supply with Alert
 Semi-Continuous
 System Monitoring
 User friendly
 Indicates Failure Mode
 Improved Power/Volume Ratio
 Anode Cube
Introduction
Microbial Fuel Cells
Regulation
Monitoring
Feeding/Case
Decision-Making Process
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Brainstorm (Group and Individual)
Discuss Design Requirements
Research
Design
Present Design to Team
Refine Design
Present Refined Design to Team
Order Parts
Assembly
Testing
Introduction
Microbial Fuel Cells
Regulation
Monitoring
Feeding/Case
Project Division
Four Main Parts of Our
Biobattery Project
 Microbial Fuel Cells
 Monitoring
 Regulation
 Feeding and Waste
Introduction
Microbial Fuel Cells
Regulation
Monitoring
Feeding/Case
How Microbial Fuel Cells (MFC) Work
Story of Electrons:
Anode
•Electrons from Acetate to
Geobacter
•Geobacter sends electrons
outside itself to electrode
Cathode
•Electrons combine with
Oxygen and Protons to form
water
Schematic courtesy of Derek R. Lovely
(Microbial Energizers: Fuel Cells the Keep Going?)
Introduction
Microbial Fuel Cells
Regulation
Monitoring
Feeding/Case
Microbial Fuel Cells
 Bacteria: Geobacter Metallireducens
 Electrode Material: Carbon Cloth
 Membrane Material: Nafion vs Cellophane
 Membrane Electrode Assembly: Sandwich
 Facultative Aerobic Bacteria
Introduction
Microbial Fuel Cells
Regulation
Monitoring
Feeding/Case
Regulation
 Output: 4.75V-5.25V, 100mA-500mA for USB
Compatibility
 Must step up voltage from 3.0V to 5.0V
 Will use the Maxim MAX1524 Boost Controller
Introduction
Microbial Fuel Cells
Regulation
Monitoring
Feeding/Case
Regulation
Introduction
Microbial Fuel Cells
Regulation
Monitoring
Feeding/Case
Parallel vs. Series Configuration
Regulator
M
F
C
Regulator
M
F
C
Fault signal
Monitor
Parallel Configuration
Introduction
Microbial Fuel Cells
Fault signal
Monitor
Series Configuration
Regulation
Monitoring
Feeding/Case
Monitoring System
 Goal
 Monitor the status of the system and communicate
relevant status to user
 Requirements
 Update user the system status



feed and waste removal
voltage produced by MFC
circuit integrity, for e.g. over-current, short circuit
 Use minimum power to monitor the system
 User friendly
 Components RoHS compliant and lead free
Introduction
Microbial Fuel Cells
Regulation
Monitoring
Feeding/Case
Monitoring System
Initial State
Waste
Interrupt
Vin MFC
Output
interrupt
alert
good
warning
bad
State Machine
Introduction
Microbial Fuel Cells
Regulation
Monitoring
Feeding/Case
Monitoring System
 AVR butterfly kit
 Atmega169 microcontroller
 10 bit ADC & LCD
 Low power
consumption: < 500µA
 RoHS compliant
 No speciality
hardware/software need
for programming
Introduction
Microbial Fuel Cells
Regulation
Block diagram
Monitoring
Feeding/Case
Anode Cube
Waste
Output
Food
Input
Electrode
Location
(Each Face)
Introduction
Microbial Fuel Cells
Regulation
Monitoring
Feeding/Case
Feeding and Waste System
 Food Solution Bladder
 Tubes and Valves
 Thumbscrew Valves to Control Rate
 Check Valves to Prevent Backflow
 Cubes Fed in Sets of 2, Bottom to Top
 Waste Tank
Introduction
Microbial Fuel Cells
Regulation
Monitoring
Feeding/Case
Feeding and Waste System
Food Solution Bladder
Replaced by User Periodically
Anode
Cube
Cathode
Tank
Anode
Cube
Anode
Cube
Anode
Cube
Waste Tank
Emptied by User Periodically
Introduction
Microbial Fuel Cells
Regulation
Monitoring
Feeding/Case
Conclusion
 Achieved Goal of Advancing Existing Designs Toward
Feasible Product
 Future Projects
 Full Testing of Cellophane Membrane
 Produce Smaller Cube: Fabrication Methods
 Platonized Electrodes to Allow Air Cathode
Acknowledgements











Professor Ray Hozalski, Civil Engineering, University of Minnesota – Twin Cities, for
samples/supplies of electrodes, membranes, and information on MEAs.
Chris Harrington, Graduate Student Researcher, University of Minnesota – Twin Cities, for help
with implementation procedures.
Professor Randall Brouwer, Engineering Department, for supplying VHDL code for ADC interface.
Sam Brower, Media Productions Calvin Alum, for various visual design and photographic assistance.
Bob DeKraker, Engineering Department, for logistical support with procurement of circuit
components.
Rich Huisman, Chemistry Department, for assistance with salt bridge supplies.
Lori Keen, Biology Department, for assistance in biological procurement and lab support.
Professor Walter Rawle, Engineering Department and Senior Design Team Mentor, for meeting
with our team and assisting us with the in progress reviews.
Professor Gemma Reguera, Michigan State University, for providing technical information and
expertise.
Professor J. Aubrey Sykes, Engineering Department, for his ongoing role as the senior design
advisor and for all of this feedback about our project.
Professor John Wertz, Biology Department, for assistance in Microbiology growth and
experimentation.
Questions?