2.7V 20F farad capacitor
(1) The working temperature limit is wide. Since the adsorption and desorption rates of ions in the supercapacitor do not change much at low temperatures, their capacity changes are much smaller than those of batteries. Commercial supercapacitors have an operating temperature range of -40°C to +80°C.
(2) Maintenance free. The supercapacitor has high charging and discharging efficiency, has a certain tolerance to overcharge and overdischarge, and can stably charge and discharge repeatedly, and theoretically, maintenance is not required.
(3) Green and environmental protection. Supercapacitors do not use heavy metals and other harmful chemicals in the production process, and have a long life span, so they are a new type of green power source.
The main parameters
1) Lifetime: When the internal resistance of the supercapacitor increases, the capacity reduction j is within the specified parameter range, and its effective use time can be extended, generally related to its characteristics as specified in Article 4. The impact on life is active dryness, increased internal resistance, and the ability to store electrical energy drops to 63.2%.
2) Voltage: The supercapacitor has a recommended voltage and an optimal working voltage. If the used voltage is higher than the recommended voltage, the life of the capacitor will be shortened, but the capacitor can work continuously for a long time under the high voltage state, and the activated carbon inside the capacitor will decompose to form a gas. It is advantageous to store electrical energy, but it can't exceed 1.3 times of the recommended voltage, otherwise the supercapacitor will be damaged due to the high voltage.
3) Temperature: The normal operating temperature of the supercapacitor is -40 to 70 °C. Temperature and voltage are important factors influencing the life of supercapacitors. For every 5 °C increase in temperature, the life of the capacitor will drop by 10%. At low temperatures, increasing the operating voltage of the capacitor, the internal resistance of the capacitor does not rise, and the efficiency of use of the capacitor can be improved.
4) Discharge: In the pulse charging technology, the internal resistance of the capacitor is an important factor; in the small current discharge, the capacity is an important factor.
5) Charging: There are many ways to charge the capacitor, such as constant current charging, constant voltage charging, pulse charging, etc. During the charging process, connecting a resistor in the capacitor circuit will reduce the charging current and improve the battery life.