Super capacitor mode structure diagram

The supercapacitor mode is created to address the limitations of the above two structures, because the maximum output current of the first two structures is limited by the battery usage specifications. If it is assumed that the operating current can reach 1A and the output voltage is twice the input voltage, according to the efficiency expression given above, assuming that the average efficiency of each can reach 80%, then the current mapped to the input end can reach 2.5A, which will cause over-discharge and a large voltage drop, which is not allowed for lithium-ion batteries. Therefore, when the current that the input battery needs to provide is greater than 2A or more, it is necessary to limit the battery output current, and accordingly, a storage capacitor is required at the load end, with a capacitance generally ranging from 0.2F to 1F. Figure 10 is a definition based on this concept.

Figure 10: Supercapacitor mode structure diagram

As for the working principle of this new structure, firstly, the super capacitor is charged through a current limiter designed with a capacitive or inductive structure. When a high-power power consumption module, such as a high-brightness LED and a radio frequency power amplifier, needs a large driving current to work in a short time, the energy is mainly provided by the super capacitor. Of course, the limitation of this structure is that it still cannot work in a high current state for a long time. FIG11 is a charging and a complete discharge and charging process of the super capacitor structure controlled by the current shown in FIG10 with an inductive structure as a current limiter. It can be seen from the charging process in the figure that under the control of the current limiter, the super capacitor obtains energy and the potential is improved, so that the driving ability is guaranteed; when rapid discharge is required, the current limiter itself acts as a driving source and outputs energy to the load together with the super capacitor. After completing a working cycle, the super capacitor is charged again to obtain energy. This guarantees the safety of battery use and the stability of the system to the greatest extent.