<p>A stable and efficient battery management system (BMS) is essential for the power supply capability of a battery pack, motivating the need for improved energy balancing techniques. Traditional active balancing technology, commonly used in current BMSs, requires repeated charging and discharging of batteries, which can lead to reduced battery life and excessive energy loss. To address these issues, this paper proposes a method and topology for the primary transfer of battery pack energy based on energy state. The process involves treating transfer current as a variable and employing a capacity efficiency equation to correct errors from fluctuations in charging and discharging rates during the energy state calculation of individual batteries. Additionally, it accounts for internal battery losses and establishes a transfer current matrix alongside a charging and discharging energy model to determine the optimal transfer current scheme. The results demonstrate that this approach allows for only one energy transfer per cell in the battery pack during each charging/discharging cycle, contrasting sharply with traditional methods. This innovation minimizes the detrimental effects of repeated charging and discharging on battery life, reduces energy transfer loss, and ultimately enhances the overall power supply capability of the battery pack, highlighting the advantages of this new strategy over conventional active balancing methods.</p>