This paper proposes a new topology for photovoltaic DC/DC converter with high efficiency under low input voltage and high input current. Under the circumstance of high output power of the DC/DC converter, the high input current value is expected which will have a negative effect on the design of the circuit and the stability of the system. And considering that the output characteristic and lifetime of battery are closely related to the output current of the battery, the DC/DC converter not only needs to have a wide input voltage range to regulate the constant output voltage, but also have ability to prevent the battery from working under too high output current which will decrease its lifetime. To satisfy the request of wide input voltage range and high output power of the battery, I propose a novel topology of DC/DC. By analysis and experiment, such new topology is proved to have the ability to work under low input voltage and high input current and protect the battery efficiently. And a case of 5KW prototype as the DC/DC converter is introduced to experimentally verify the proposed topology.