In this brief, a single-phase single-stage semi-dual-active-bridge (SDAB) ac/dc converter with fully soft-switched and power-factor-correction (PFC) features is proposed for battery charging applications. The unidirectional SDAB dc/dc converter is properly designed and modulated to produce a sinusoidal charging current, such that the conventional bulky intermediate-stage electrolytic capacitors are not required. Meanwhile, the input PFC function can be realized easily in the dc/dc conversion stage by means of fixed-frequency single-phase-shift modulation. As the SDAB converter is designed to operate with just continuous current mode (JCCM) or discontinuous current mode (DCM), all power switches including diodes can be switched softly. Step-by-step analysis and design procedures for the proposed ac/dc conversion scheme are provided. Finally, this brief is validated by both simulation and experimental tests.