Supercapacitors have a very wide range of uses. Combined with high-energy-density substances such as fuel cells, supercapacitors provide rapid energy release to meet high power demands, so that fuel cells can be used only as an energy source. Currently, supercapacitors can have energy densities as high as 20kW/kg and are starting to take over the market between traditional capacitors and batteries. Discharge first, especially electrolytic capacitors.

In applications that require high reliability but low energy requirements, Farad capacitors can be used to replace traditional batteries, and supercapacitors can be combined with batteries to be used in applications with high energy requirements. Smaller, more economical batteries. Use capacitors in series. Due to process reasons, the additional working voltage of unipolar supercapacitors is generally around 2.8V, so it is necessary to use them in series in most cases.

Supercapacitors have a fixed polarity. Polarity should be recognized before use. Should be used at nominal voltage. When the capacitor voltage exceeds the nominal voltage, the electrolyte will be decomposed, and the Farad capacitor will heat up, the capacity will decrease, and the internal resistance will increase, the life will be shortened, and in some cases, the capacitor function will collapse. Rapid charge and discharge at high frequency will cause internal heating of the capacitor, capacity attenuation, increase in internal resistance, and in some cases, the function of the capacitor will collapse. Supercapacitor manufacturers cannot be in places with relative humidity greater than 85% or containing toxic gases. Under these circumstances, the lead wire and capacitor case will corrode, resulting in an open circuit. The external ambient temperature has an important influence on the service life. Capacitors should be kept as far away from heat sources as possible.

Any supercapacitor will discharge through the internal parallel resistance when it is energized. This discharge current is called leakage current, which affects the self-discharge of the supercapacitor unit. The voltage of the supercapacitor module also needs to be balanced when used in series. Due to the leakage current of the supercapacitor, the size of the internal parallel resistance determines the voltage distribution on the series-connected supercapacitor units. When the voltage of the supercapacitor is stable, the voltage on each unit will change with the leakage current, not with the capacitance value. The larger the leakage current, the smaller the additional voltage, and vice versa, the smaller the leakage current, the higher the additional voltage.