Portable Fuel Cell Charger (Input Side)
Transcript of Portable Fuel Cell Charger (Input Side)
Portable Fuel Cell Charger (Input Side)
By: Aishwarya Singh and Rebecca Roecker(Team 59)
Introduction:
● People want to be able to take energy with them to grid-inaccessible places.
● To meet this demand, we require a power supply that is :
● Durable● Lightweight● Easy to use● Energy-rich
Background: Fuel Cells
● Open system electrochemical reactor.
● Uses redox reactions across a catalyzing membrane.
● Advantage vs Batteries: energy capacity is limited only by (scalable) fuel supply.
Background: Fuel Cells● Most common fuel is H2.● H2 has several issues:
○ Production○ Transport○ Safety
● Alternatives:○ Methanol.○ Ethanol.
■ Our choice.
Design: Block Diagram
Build: Fuel Cell Module● Horizon FCJJ-42 science
module.
● Ethanol in, acetic acid out reaction pathway.
● 5 to 15% ethanol in water.
● Tests done outside lab; no liquids in lab.
Build: Fuel Cell Module
Reaction Stage Chemical Equation
Anode (Oxidation)(1) C2H5OH → CH3CHO + 2e- + 2 H+
(2) CH3CHO + H2O → CH3COOH + 2e- + 2H+
Cathode (Reduction) O2 + 4H+ + 4e- → 2H2O
Total Reaction C2H5OH + O2 → CH3COOH + H2O
Current = Fuel Consumption 1 ethanol molecule = 2 electrons
Build / Test: Fuel Cell
"The Power Performance Curve for Engineering Analysis of Fuel Cells" -Kevrekidis et. al., Dept. of Chemical Engineering, Princeton University
Performance: Fuel Cell
Performance: Fuel Cell
Performance: Fuel Cell
Performance: Fuel Cell
Performance: Fuel Cell
Build: Fuel Cell to Battery● Boost Converter
● 1 LiPo battery charging
voltage is 4.2 + or - .03 Volts
● 7 batteries in series so
Vo = 7*4.2 = 29.4
● All components rated at 40
volts 2 Amps
● Fuel cell is only 0.83 Volts
Build: Fuel Cell to Battery Equations
Testing: Fuel Cell to Battery
Build: External Charging Circuit● Started with a 40 Volt .5 Amp HP
charger● Need to step down the voltage
from 40 to 29.4 Volts
Build: Battery Pack● Constructed a
battery pack accumulator.
● 2 sets of 7 GMBPower GMB652535 lithium polymer cells in parallel.
● Requirements set by our output team needs.
Requirements & Verifications
● Battery Pack:○ >= 24 V nominal operating voltage? Yes.○ >= 30 W sustained power? Yes.
● Power Conversion Circuits: ○ Required to meet parameters as described earlier.
○ Parameters met? No. Why?■ Components, impractical nature of source.
Requirements & Verifications
● Fuel Cell Module:○ Works in itself? Yes.
○ Shows fuel cell output character? Yes.
○ Usable as a source? Absolutely Not. Why?■ Reaction pathway. Carbon-to-carbon bonds.
■ Too small scale?● Ethanol to Acetic Acid cell of proper scale would be heavy.● Several hundred FCJJ-42s would be required!
Conclusions
Questions?
The End