Testing regulations for supercapacitor modules?

Testing regulations for supercapacitor modules?

A capacitor is an electronic device that can store energy between two electrodes. A supercapacitor (double layer capacitor EDLC) is an electrochemical capacitor. This enormous energy density is achieved through the large surface area of the porous carbon electrode and the minimal charge separation distance generated by the separator. The ideal characteristic of a capacitor is to have a single stable capacitance. Capacitance and each conductor! The potential difference between charges is an example.

Actually, what we measure is the average voltage.

The energy stored in the capacitor is calculated using the following formula:

In fact, the dielectric between the two plates will still pass through a small amount of leakage current, which will cause the fully charged supercapacitor to experience voltage decay over time. Other factors such as electrodes and wires can increase the equivalent series resistance (ESR). Capacity, ESR, and leakage current/white discharge are the three main parameters used to evaluate supercapacitors as energy storage devices. They represent the ability to store charges, charging and discharging efficiency, and the ability to store electricity after charging.

A supercapacitor module is a new type of energy package composed of multiple supercapacitor units connected in series, combined with a voltage balancing and discharge stabilization system, and assembled with an aluminum alloy shell. The birth of supercapacitor modules has made up for the shortcomings of energy storage devices such as lead-acid batteries. The working temperature range of supercapacitor modules is -40~65 ℃, which solves the problem of greatly reducing the efficiency of lead-acid batteries in cold outdoor conditions; Moreover, the supercapacitor module not only possesses all the characteristics of supercapacitors, but also has a visual status monitoring function, which can better achieve maintenance free and easy maintenance.

Module detection items

The appearance surface should be clean, free of rust, deformation, and mechanical damage; Is the identification clear and complete.

Among them, C capacity (F); I   Discharge current (A); U1 measures the initial voltage (V); U2 measurement termination voltage (V); The time (s) for the discharge voltage of t1 to reach U1; t2   The time (s) for the discharge voltage to reach U2. The discharge current I and the voltage U1 and U2 for the decrease in discharge voltage are shown in Figure 1.

Equipment: A. ARBIN supercapacitor testing system B. Linear DC stabilized power supply C. Constant current discharge device D. Internal resistance of voltage recorder

Test method: AC impedance method for measuring circuits

Test the measurement circuit shown.

The measurement method for the internal resistance Ra of a capacitor should be calculated using the following formula: image.png, where Ra is the AC internal resistance (Ω); U effective value of AC voltage (V r. m. s); The effective value of AC current (V r. m. s). The frequency for measuring voltage should be 1kHz. The AC current should be between 1mA and 10mA.