Abstract: The researches on parallel battery packs balancing and lower energy utilization are rarely available in the literature, thus this paper proposes a parallel battery packs balancing topology based on partial power conversion. This topology combines the dual active bridge (DAB) converter and the series resonant dual active bridge (SR-DAB) converter. A partial power conversion structure is utilized, which can greatly reduce system losses and enhance system efficiency. Based on this, aimed at the battery state of charge (SOC) equalization, the SOC balancing control is added to the single-phase-shift control of SR-DAB to achieve the balancing of charging and discharging of the battery packs. The real-time simulation results based on RT-Box indicate that the proposed topology and balancing control strategy effectively achieve equilibrium among parallel battery packs, and their system efficiency is consistently higher than that of systems employing full-power conversion (FPP) structures under varying operating conditions.