I love this quirky video by Jesse Holleran, showing a bunch of experiments he did with a 3,000-farad capacitor, including welding two pieces of metal together, melting a paper clip, and electrolyzing water into oxygen and hydrogen.
An ultracapacitor, also called a supercapacitor, is an electrical component capable of holding hundreds of times more electrical charge quantity than a standard capacitor. In some situations, an ultracapacitor can take the place of a rechargeable low-voltage electrochemical batteries! Ultracapacitors deliver high amperage of relativity low voltages. The ultracapacitor charges up with direct-current (DC). Interesting fact: ultracapacitors keep working at temperatures far below freezing and most electrochemical batteries don’t work well at extremely low temperatures.
Capacitors can be dangerous, so don’t attempt any of these experiments unless you really know what you’re doing.