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© KEMET Electronics Corporation • P.O. Box 5928 • Greenville, SC 29606 • 864-963-6300 • www.kemet.com

S6018_FA • 3/30/2017

Supercapacitors – FA Series

Notes on Using Supercapacitors or Electric Double-Layer Capacitors (EDLCs)

1. Circuitry Design

1.1 Useful life

The FC Series Supercapacitor (EDLC) uses an electrolyte in a sealed container. Water in the electrolyte can evaporate

while in use over long periods of time at high temperatures, thus reducing electrostatic capacity which in turn will create

greater internal resistance. The characteristics of the supercapacitor can vary greatly depending on the environment in

which it is used. Basic breakdown mode is an open mode due to increased internal resistance.

1.2Failrateinthefield

Basedonfielddata,thefailrateiscalculatedatapproximately0.006Fit.Weestimatethatunreportedfailuresareten

times this amount. Therefore, we assume that the fail rate is below 0.06 Fit.

1.3 Exceeding maximum usable voltage

Performance may be compromised and in some cases leakage or damage may occur if applied voltage exceeds

maximum working voltage.

1.4 Use of capacitor as a smoothing capacitor (ripple absorption)

As supercapacitors contain a high level of internal resistance, they are not recommended for use as smoothing

capacitors in electrical circuits. Performance may be compromised and, in some cases, leakage or damage may occur if

a supercapacitor is used in ripple absorption.

1.5 Series connections

As applied voltage balance to each supercapacitor is lost when used in series connection, excess voltage may be

applied to some supercapacitors, which will not only negatively affect its performance but may also cause leakage

and/or damage. Allow ample margin for maximum voltage or attach a circuit for applying equal voltage to each

supercapacitor (partial pressure resistor/voltage divider) when using supercapacitors in series connection. Also,

arrange supercapacitors so that the temperature between each capacitor will not vary.

1.6 Case Polarity

The supercapacitor is manufactured so that the terminal on the outer case is negative (-). Align the (-) symbol during

use. Even though discharging has been carried out prior to shipping, any residual electrical charge may negatively affect

other parts.

1.7 Use next to heat emitters

Usefullifeofthesupercapacitorwillbesignificantlyaffectedifusednearheatemittingitems(coils,powertransistors

and posistors, etc.) where the supercapacitor itself may become heated.

1.8 Usage environment

This device cannot be used in any acidic, alkaline or similar type of environment.