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In Figures 6, 7, the yellow waveform represents the pulse sequence of the voltage. The peak voltage is 10V. The green waveform represents the current state of discharging the battery with the higher power. Purple waveform represents the current state of charging the battery with lower power. The peak value of the charging current is 2A. When the switch is turned on, the battery with a higher power is gradually discharged, and the battery with lower power remains unchanged. When the switch is turned off, the battery with higher power remains unchanged, and the battery with lower power is rapidly charged. Therefore, the difference between the cells gradually becomes smaller, and the equalization process ends until the error meets the equalization requirements. Comparison and Results Analysis Figure 4(b) shows an equalization unit EU1-1 in greater detail, including two inductors ( L1 and L2) and four MOSFETs ( S1, S2, S3, and S4). High-layer units are utilized to transfer energy between any two cells, which speeds up the equalization, increases the battery energy usage, and reduces energy loss. The dual inductors replace the conventional single inductor and increase the cell operating time during an equalization cycle. This way, the circuit avoids keeping the battery idle for a long time and increases the equalization speed. The layer number and unit number per layer are determined by equations ( 1) and ( 2), respectively: where m is the number of equalization layers, n is the number of cells in the series-connected battery, [−] represents the Gaussian rounding function, and a is the number of equalization units in layer i. 2.1. Working Principle Hong, S.; Jiang, J.; Li, X. A battery management system with two-stage equalization. In Proceedings of the 29th Chinese Control and Decision Conference, Chongqing, China, 28–30 May 2017. [ Google Scholar] Assuming that t is equal to T, the duty cycle D and voltages should meet the following requirement: Summary statistics of the SOC estimation result of the three Kalman filter methods. 5.2. Performance Evaluation of the Proposed MLDIECMay, G.J.; Davidson, A.; Monahov, B. Lead batteries for utility energy storage: A review. J. Energy Storage 2018, 15, 145–157. [ Google Scholar] [ CrossRef] Zhu, C., Han, J., Zhang, H., Lu, F., Liu, K., and Zhang, X. (2021). Modeling and Control of an Integrated Self-Heater for Automotive Batteries Based on Traction Motor Drive Reconfiguration. IEEE J. Emerg. Sel. Top. Power Electron. doi:10.1109/JESTPE.2021.3119599

Silva, P.S.; Bastos, A.; Libonati, R.; Rodrigues, J.A.; DaCamara, C.C. Impacts of the 1.5 °C global warming target on future burned area in the Brazilian Cerrado. For. Ecol. Manag. 2019, 446, 193–203. [ Google Scholar] [ CrossRef] Lu, C.; Kang, L.; Luo, X.; Linghu, J.; Lin, H. A novel lithium battery equalization circuit with any number of inductors. Energies 2019, 12, 4764. [ Google Scholar] [ CrossRef][ Green Version] The first time you use the equalizer, it is required to charge, and then stop until you are satisfied. Remember to keep the charger plugged in and don't unplug it!Dai, H.; Wei, X.; Sun, Z.; Wang, D. A novel dual-inductor based charge equalizer for traction battery cells of electric vehicles. Int. Electr. Power Energy Syst. 2015, 67, 627–638. [ Google Scholar] [ CrossRef]