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Supercapacitors – FT 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.
1.2Failrateintheeld
Basedonelddata,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
Usefullifeofthesupercapacitorwillbesignicantlyaffectedifusednearheatemittingitems(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.