09-11-2012, 02:20 PM
electric double-layer capacitor (EDLC)
Introduction
An electric double-layer capacitor (EDLC), also known as supercapacitor, supercondenser ,electrochemical double layer capacitor, or ultracapacitor, is an electrochemical capacitor with relatively high energy density. Compared to conventional electrolytic capacitors the energy density is typically on the order of hundreds of times greater . In comparison with conventional batteries or fuel cells, EDLCs also have a much higher power density.
Advantages
• Low cost per cycle
• Good reversibility
Very high rates of charge and discharge.
Extremely low internal resistance (ESR) and consequent high cycle efficiency (95% or more) and extremely low heating levels
High output power
Disadvantage
Has the highest dielectric absorption of any type of capacitor.
High self-discharge - the rate is considerably higher than that of an electrochemical battery
Applications
Used in pulsed application to share the load and for providing peak power assistance to reduce the duty cycle on the battery to prolong battery life in products or devices using mechanical actuators such as digital cameras.
Also used for energy storage for solar panels and motor starters