Why ultra capacitors are called so ?

Question

Why ultra capacitors are called so ?

Answer 1

Ultracapacitors or supercapacitors are a cross between a capacitor and a battery.  They work on charge but are limited to hundreds of thousands of charge/discharge cycles.

They have high capacitance values (ex 3F) in small packages, but have a low voltage limit (ex 2.5V).  This puts their capabilities below batteries, but there are limitations in combining supercapacitors (in series or parallel), so research is required before they are really useful.  The use of supercapacitors in electric or hybrid vehicles is driving much of the research.

Answer 2

Because the capacitance is much higher than you would get with a standard electrolytic capacitor of the same size.

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