5.1  Introduction

• A supercapacitor is a device that, unlike the standard capacitor, can store relative to its size a high level of energy (referred to as high energy density).
  
  
• It has a significantly higher capacitance rating than the standard capacitor (in excess of 1,000 times greater). Comparison farad figures required.
  
  
• It is also called an ultracapacitor.