Starting battery system for cell balancing of Lithium battery pack and capacitor

摘要

The present invention relates to a starting battery system through cell balancing of a lithium battery and a capacitor. The starting battery system of the present invention comprises: a plurality of battery cells connected in series; a capacitor unit connected to each of the battery cells to charge or discharge the same; a switch unit provided between the battery cells and the capacitor unit, and selectively turning on and off a charge/discharge path; and a DC-DC converter separately connected to the battery cells and the switch unit in parallel, and performing cell balancing for charging or discharging of the battery cells (100). Accordingly, the battery cells and the capacitors are connected to an SWDC switch of the DC-DC converter in parallel, thereby controlling voltage of the overcharged battery cells to be discharged to the capacitor. Also, a low-charged battery cell is cell balanced by allowing shared surplus power of the capacitor to be charged to a corresponding battery cell, thereby minimizing energy loss through the cell balancing by the DC-DC converter. In addition, a structure which can simultaneously perform charging and discharging is provided, and various systems can be configured regardless of the number of battery cells.