I’mSupercapacitors and Energy

Storage

Stuffed !!

Written by Jim Lehman

Is This Possible?

Energy Problems and Solutions

• Today we are facing a crisis related to Energy

• How do we use Energy?

Energy Problems and Solutions

Fuel Cell Cars

• Flexible fuels• Make water as only by-

product• Accelerate slowly• Need larger fuel cell

than ideal if you want acceleration

• Fuel cells are very expensive!!!!

Battery Electric Cars

• Store electric energy in battery pack

• Have no emissions from car itself

• Often have limited range

Fast Electric Car

Hybrid Cars• Use combination of

power sources

Wanted: a Sidekick

Regenerative Braking

Feel the Force!• Find the generator in your kit

box• Work with two people at a

time• Be Gentle! Don’t abuse the

generator• One person should slowly

turn the crank, and the other one should touch the wires together while the crank is being turned

• Does the crank always require the same amount of force to turn?

Feel the Force!• Was the generator

harder to turn with the wires touching or not touching?

• Where did the energy come from?

• Where was the electricity flowing?

• What happened to the electrical energy?

Energy Storage Options

• Battery Pack

Energy Storage Options

• Ultracapacitor Pack

What is capacitance?

• The storing of electric charge

• Discovered in 1745 by 2 Dutch scientists

• Device was called a Leyden Jar

Discovery of capacitance

• Ewald Georg von Kleist

• Experimented with effects of electricity on water in a bottle

• When he touched the bottle later. . .

I wonder if that’s a good idea. . .

“I would not take a second shock for the kingdom of France”

Simple Capacitor

• Two parallel plates or sheets

• Separated by an insulator so they do not touch

Testing Capacitors

• What factors affect the energy storage of capacitors?

Activity: Testing Capacitors

• Conduct an investigation to find out what factors affect capacitance.

Activity: Testing Capacitors

Materials:

• Top and bottom foil sheets in plastic

• Capacitance meter

Activity: Testing Capacitors• Arrange sheets to overlap halfway• Take a reading, and record on your data sheet• If meter changes, choose a number that you think is showing up

more than others

Activity: Testing Capacitors• Slide sheets together, watching the meter as they overlap more and

more.• Take a final reading, and record on your sheet• If meter changes, choose a number that you think is showing up

more than others

Activity: Testing Capacitors• Press down on the top sheet, first a little, than

more• Watch the effect of pressure on the capacitance• Record the highest reading you got on your

sheet

What Affected Capacitance?

• Surface area of plates

• Spacing of the plates

• Any other factors?

Introducing: Ultracapacitor

Ultracapacitors

• Hold much more charge than ordinary capacitors

• Able to gain and lose charge quickly

Ultracapacitors

• Hold much more charge than ordinary capacitors• Able to gain and lose charge quickly

Ultracapacitors

• Use Nanotechnology to improve ability to store electrical energy

Nanotechnology to the Rescue!

• What two factors did we test earlier to see how they affected capacitance?– Surface Area– Spacing between the plates

• Nano-particles have much more surface area• An ultracapacitor the size of an egg could have a

surface area the size of 50 soccer fields!

Source: http://www.colin.org/SmallStuff/Ultracapacitors.html

Nanotechnology to the Rescue!

• The spacing is extremely close!

• The particles would be 40,000 times closer than the sheets of plastic that we used to separate the foil sheets

How Can Ultracapacitors Help?• Hybrid cars recover energy normally wasted

during braking• Car’s motion is used to generate electricity• The electricity can be stored and released

when the car starts moving again.

Comparing Ultracapacitors and Batteries

• Follow Directions on Activity Sheet• Test performance of battery twice• Test performance of ultracapacitor twice• Record the data on your chart

And the Winner Is?

• Which device made the car run longer?

• How does this compare with other groups in your class?