The service life of an EDLC is affected by the operating temperature. Generally, the rule of double the life for every 10˚C of temperature decrease applies, as it does for aluminum electrolytic capacitors.
The life expectancy can be roughly calculated using the equation below.
The operating temperature is not the ambient temperature of the device; it is necessary to check the temperature of the capacitor including the heat generated by charging / discharging electricity.
What precautions are required for using EDLCs in series?
To use EDLCs in series, it is necessary to consider the issue of unbalanced voltage being applied to the capacitor and allow a sufficient margin with respect to the rated voltage of the capacitor, or else to add a circuit to balance the voltage, such as by inserting a voltage dividing resistor parallel to each capacitor, taking leakage current into account.