The advancement in SEPIC dc-dc converter can be done with the use of snubber circuit. A new approach for this improvement of SEPIC converter is used for high power factor rectifiers. Ac-dc conversion of electric power is widely used in different applications like as in adjustable-speed drives, switch-mode power supplies, uninterrupted power supplies, and utility interface with nonconventional energy sources such as solar Photovoltaic etc., battery energy storage systems, in process technology such as electroplating, welding units, etc., battery charging for electric vehicles, and power supplies for telecommunication systems, measurement and test equipment's. In the present time, SEPIC converters are widely used in various industrial and commercial applications. These converters provide well controlled and regulated dc to dc conversion. These converters provide comfortable and flexible operation of the system. SEPIC converter based products operate from batteries which benefits most from the wide ranging step down and step up operating modes of the SEPIC topology.