
TIME REQUIRED:
1–2 Hours
DIFFICULTY:
Easy
COST:
$10–$20
MATERIALS
» Aluminum foil
» Activated carbon Regent Aqua-Tech or Tetra
Whisper Filter Cartridges, from aquarium store
» Lemon juice bottled or fresh
» Clip leads (2)
» Tray
» Battery, 1.5V or less AA, AAA, C, or D size
TOOLS
» Stapler
» Voltmeter (optional)
obvious feature is the nearly instantaneous
charge time, which is far faster than typical
conventional capacitors.
You can charge a DIY supercap to a higher
voltage by stacking multiple layers. In Science
and Communication Circuits and Projects
(sparkfun.com/products/11132), one of my
RadioShack Engineer’s Mini-Notebooks, I
describe ...