This paper presents a high-efficiency battery charger with cascode output design. The output voltage is cascode comprising two parts: one is fixed and the other is variable. High efficiency can be achieved under a wide range of output voltage variations. This topology can increase the utilization of transformer duty cycle and reduce the power loss. The constant current and constant voltage charging schemes can be achieved by the proposed cascode configuration for battery charger applications. A 3.3 kW laboratory prototype is implemented and tested. The experimental results verify the feasibility of the proposed scheme.