The DM Series of TekStak Fuel Cell Stacks provides you with a ready to use, pre-tested direct methanol fuel cell stack. This series of stacks is designed for users who are interested in studying DMFC technology and learning about the trade off associated with using a liquid fueled, lower power stack versus a gas fueled, higher power stack. The DM products are designed around a “closed cathode” design that requires a pump or compressed air supply to force air through the stack. A liquid pump is needed to supply the stack with a dilute fuel mixture of methanol and water.   The DM products include membrane-electrode assemblies (MEAs) designed specifically for use with methanol as the fuel source. 

 

Each stack comes with instructional materials to get you started and to help you disassemble the stack should you wish to investigate how it is put together. A DVD that demonstrates the proper construction of the stack and explains how fuel cells work is included along with an easy to read manual with more detailed information. The stacks can be easily disassembled for easy storage when not in use and rebuilt later if desired.

 

Stacks are available in three sizes—1 cell, 5 cell, and 10 cell. In addition to the instructional materials described above, each kit includes

Molded Plastic Endplates

Parker TrueSeal® Fittings to hook up flow lines

Graphite Composite Bipolar Plates

5 mil Membrane-Electrode Assemblies (MEAs)

PTFE Gaskets

Nickel Plated Current Collector Plates

Assembly Hardware

The DM TekStak is a direct methanol fuel cell (DMFC). DMFCs work very similar PEM fuel cells, such as the HA and HP versions of the TekStak. The major difference is that the special MEA design used for DMFCs allows for the use of a more complex fuel molecule, methanol (CH₃OH). 

 

Here is the reaction that occurs within a DMFC:

 

Anode (fuel) side:         CH₃OH + H₂O → CO₂ + 6H⁺ + 6e^-

Cathode (air) side:        3/2O₂ + 6H⁺ + 6e^- → 3H₂O

 

This chemical reaction releases energy in the forms of heat and DC electricity. If you connect a load to the stack, such as a small fan or LED lamp, the electricity will flow powering the fan or lamp. 

 

 

Just like with batteries, the more fuel cells you have the more power you get out. The VI and power curves shown on this graph give the typical power output of a 5 cell DM TekStaks at 35ºC and 50 ºC.