Fill 'Er Up: Fuel Cells for Cell Phones

Need to make one more call on your cell phone before heading homeward, but the "Low Battery" light is flashing? What developments might provide longer battery life in the future?

Motorola Inc. and the Los Alamos National Laboratory are developing miniature fuel cells to replace batteries in cell phones. A fuel cell is like a battery powered by a fuel tank. Instead of needing to be recharged like a regular battery, fuel cells need to be "refilled" like a car's gas tank.

The proposed fuel cells will run on alcohol mixed with water and oxygen derived from the air. The fuel will be supplied in small containers that you slip into your mobile phone or other small electronic appliances. Motorola predicts that the fuel cell will run 10 times longer than current batteries. The only waste emitted by the cell is water vapor.

Researchers predict that commercial use of the tiny fuel cells is two to five years away.

Students can read more about the fuel cells:

• "Laptops That Run on Alcohol"

Students can learn how a typical battery works in the Chemistry Gateways activity, Voltaic Cells. Point out to students that a fuel cell is a voltaic cell that uses a combustion (oxidation) reaction as its cell reaction.

According to Bill Ooms of Motorola, a major challenge facing the technology is the catalyst chemistry—finding the right mixture to promote the reaction. Students can learn more about what a catalyst is in the Chemistry Explorer activity, Add a Catalyst.

Analyzing the Problem
Ask students: Why does a regular battery (voltaic cell) need to be recharged after a period of time?

Have students watch this Fuel Cell Animation. Then ask: Why does a fuel cell need to be refilled, not recharged?

Extending the Problem

• Students who want to read more about fuel cells can visit Fuel Cells 2000. This site offers basic information explained in simple language.

• Advanced students can read and print the report, "Making Electricity with Hydrogen." (Requires Adobe Acrobat Reader. Download now.) While the project may be too complex for students to build their own fuel cells, the descriptions and the photos may help them understand what a fuel cell is.

• Fuel cells are only one type of alternate energy being researched for replacing gasoline-powered combustion engines in automobiles. Have students visit the following sites. Ask them to prepare a list of the pros and cons of fuel cells, electricity, and solar power as possible energy sources for cars. Ask them to define a hybrid electric vehicle and discuss its advantages.
  
  Fuel Cells
  
  
  • California Fuel Cell Partnership: Driving the Future
    

• Fuel Cells in Transportation

Electricity

• Riverdeep's, "Connecting with Electric Cars"
  
  
• U.S. Department of Energy Hybrid Electric Vehicle Program
  
  
• Electric Vehicle Association of the Americas

Solar Power
Sunrayce is a biennial race of solar-powered cars designed at various universities. Read about the design of some of the cars entered in the race:

• Solar Car FAQs (Berkeley Solar Car)
  

• Sunseeker (Western Michigan University Solar Car Project)
  
  
• Team Lux (Yale College Solar Racing)