Build Your Own Fuel Cells

by Phillip Hurley

Table of Contents with sections, chapters and text subheads

Introduction

A short history of the fuel cell

Grove's "gas battery"
Fuel cells today

What exactly is a fuel cell?

Fuels for fuel cells

Many sources of hydrogen
Fuel delivery packages
Hydrogen from fossil fuels
Hydrogen from water
Technology of the future
Global impact
Storing hydrogen
What is a fuel?
Water is a fuel
Who bears the real costs?
Skeletons in the closet
The hydrogen-water economy is coming!
Water based hydrogen production
Electrolyzers
Solar, wind and hydro power for electrolyzers
Photo-electrolysis
Photo-biological

Types of Fuel Cells

Operating temperatures
Regenerative fuel cells

Systems & Components Overview

Photovoltaic fuel cell systems

Fuel cells vs. batteries
Components of a PV fuel cell system
Wind or small hydro power
Add-ins for the system
Fuel cell configurations
Matching the PV panels to your needs
Powering the electrolyzer
Building an electrolyzer
Compressing the hydrogen
More resources
Building a PV panel for your electrolyzer
Figuring PV panel costs
Wiring the system
Support and use components
Housing the system
Control valve

PEM fuel cell components

MEA basics
Purchasing MEAs and components
Surplus fuel cells

Building the K18 Hard Graphite
Convection Single Slice Fuel Cell

K18 Fuel Cell - Tool list

K18 Fuel Cell - Materials list

About the materials

Buying membrane electrode assemblies and components
Mounting the membrane electrode assembly
Rubber gaskets and spacers
Keep the components clean
Working with graphite
Obtaining graphite
End plates
Miscellaneous parts
Fuel cell jazz

Simple tools do the job

Wet and dry bandsaw
Drill press
Setting up for fuel cells

Preparing the graphite

Buy graphite pieces that fit your saw
Setting the water flow
Slabbing the graphite
Begin to cut
Fences
Ripping gauges
Plan the cuts carefully
Cut extra pieces
Err on the thicker side
Cut the plate to size
Sanding
Sanding surface and technique
Cleaning the bandsaw
Using the templates
Drilling the holes
Routing the vertical flow fields
Routing the serpentine flow fields
Routing the serpentine flow fields

Preparing the other parts

End plates
Gas gaskets and spacers
Mylar surrounds for the MEA (membrane electrode assembly)
Handling the MEA (membrane electrode assembly)
Assemble the MEA in the Mylar surround
Electrode plate materials
Cutting the electrodes
Gas entry ports
Fasteners

Assembling the K18 fuel cell

Testing fuel cells

Building an electrolyzer
Buying an electrolyzer
Hook up the hydrogen
Precautions
Turn on the hydrogen
Meter readings
Test for continuity within the cell
Troubleshooting – no reading
Convection process

Electrolyzers

How electrolyzers work

Electrolytes
Applying electricity
Types of electrolyzers
The tank electrolyzer
Home-built electrolyzers
The electrolyte
Preparing the electrolyte
Safety precautions

Building the P38 electrolyzer

Tools needed
Materials needed
Purpose of the P38
Use at your own risk
Electrode separators
A transparent electrolyzer
Nickel electrodes
Preparing the parts for assembly
Bottom cap
Height gauge
Maintaining the electrolyte level
Increasing amperage to the electrolyzer
Sealing the electrolyzer
Silicone cement vs. epoxy
Preparing screws and nuts
Epoxy the pipe to the bottom cap
Dry the seals and test
Aligning the top and bottom caps
Wiring it up
Filling the electrolyzer
Connecting to power

Scrubber

Vinegar
Building a scrubber
Inside tube length
Transparent scrubbers

Making an electrolyte

Tools needed
The filter bucket
The drip bucket
Add ashes and water
Wait 3 days to a week
Collect the KOH solution

Building the L78 Soft Graphite
Convection Single Slice Fuel Cell

Tool and materials list

Tools
Materials needed

Really simple tools do the job

Stick technology
Make it on your kitchen table
Print out the templates
Endplate/current collectors
Mark the end plates
Cut and drill the end plates
Soft graphite
Practice with the material
Cutting the soft graphite
Working with soft graphite
Drilling holes in soft graphite
Mark the flow fields
Making the flow field grooves
Soft graphite is forgiving
Easy construction and high performance
Aligning the holes
The hose connectors
Prepare the fasteners
Prepare the MEA
Assemble the fuel cell

Designing Fuel Cells

Ideas for designing fuel cells

Fuel cell geometry
Buckyballs
Ceramics in fuel cells
Wooden fuel cells
Carbonizing other materials
Other natural materials for inspiration
"Biomimicry" for fuel cells
Collect supplier catalogs
Learn from the materials
Thinner and lighter designs
Use easy to obtain materials and tools
End plate materials
Plastics in fuel cells
General materials considerations
Convection vs. oxygen-hydrogen
Planning for maintenance
Banded fuel cells
Gas port plate
Stack design considerations - hardware
Longevity
Operating environment
In summary

Building stacks

Bipolar plates
Plate thickness and groove depth
Gas feed in the gasket
Stack templates
Convection stack configuration
Oxygen-hydrogen stack configuration
Plan for easy disassembly
Larger stacks need gas pressure
Gas flow regulator
Additions to optimize performance
Gasket thickness affects performance

Experimental Methods for Making MEAs
(Membrane Electrode Assemblies)

About membrane electrode assemblies

MEA components
Applying the catalyst to the substrate
1. Sputter diffusion
2. A Benjamin Franklin technique
Resources for the experimenter
3. Electrochemical deposition
4. Electroless deposition
5. Mechanical Deposition
Powdering platinum
Carbon nano-tubes
Carbon and platinum mixtures
6. Electrostatic dispersion
7. Simple mixing
8. Photochemical
Platinum black
Application techniques
Brewster's reaction
Other methods to get platinum black

MEA - Tool list

MEA - Materials list

Loading the catalyst - an experimental method

Making percent solutions
MEA components
The substrate and catalyst
Construction overview
Planning to load the catalyst
Carbon cloth substrate
Cutting the cloth
Weighing the chemicals
Safety precautions
The work area
Safelight conditions
Timing and storage
Making the solution
Handling AFO
Procedure summary
Preparing the platinum solution
Water bath
Making the platinum solution
Use a brush with no metal
Coating the carbon cloth
Make a test paper
Dry the fabric pieces
Expose to UV
Washing out the ferrous salts
Other washing methods

Preparing the proton exchange membrane (PEM)

Membrane thickness
Handling the membrane
Membrane preparation
Bathing the membrane
Keep a steady temperature
Safety precautions
Keeping the membrane immersed
The first two baths
Fishing for the invisible membrane
The third bath
Last three baths
Pressing plates
Coat plate with powdered graphite
Lay out the MEA layers
Add the top plate carefully
Clamp the sandwich
Cook the sandwich
Increase the pressure

Further experiments

Lower the loading
Increase the loading
Matching gaskets to MEAs
What to expect from your MEA
Testing fuel cells
Basic test equipment

Resources

Links

Books

Supplier contact information

MSDS

Templates

How to use the templates

K18 single slice convection
P38 Electrolyzer
L78 single slice convection
K18 single slice oxygen hydrogen
L78 single slice oxygen hydrogen
K18 convection stack
K18 oxygen hydrogen stack
Surround gasket with feed tunnels