（1）The supercapacitor to be tested should be fully discharged before testing the leakage current, generally for more than 1 h;
（2）Apply rated voltage across the capacitor UR;
（3）After the super capacitor voltage reaches the rated voltage UR, measure the voltage across the series protection resistor
Calculate leakage current：
*Leakage current (mA);
UV：Voltage across the series resistance (V);
R：Series protection resistance, generally 1000 Ω and below.