Dual-active bridge (DAB) is widely used in new energy power generation systems due to the advantages of electrical isolation, bidirectional energy flow and easy to realize soft-switching. However, when it’s applied to the charging and discharging of batteries, the widely change of output voltage leads to long-term voltage mismatch between the two ends of the transformer, which will cause the DAB to lose soft-switching. This paper proposed a natural soft-switching optimization method in the full power range based on extended-phase-shift(EPS) control and ensured the current stress is minimized. In order to enhance the dynamic performance, the output current closed-loop control scheme is proposed to ensure that the fast dynamic response can be achieved while achieving the minimum current stress. Finally, the rationality and reliability of the method used in this paper are verified by experimental comparison.