In order to solve the problem of battery consistency management in the practical application of wind and solar storage

household storage

mobile storage

and other energy storage areas

we have proposed a battery group topology with the multi-module parallel-input and series-output（MPISO）.The battery module consists of 36 single cells in parallel; direct current to direct current converter（DCDC） is a new type of switching power supply

and can achieve two-way bulk and boost; the battery module and a DCDC constitute a power module; a high voltage system is composed of power modules in series.Based on this topology

a second-use battery energy storage system is designed and tested.The results show that the energy storage system can quickly cluster SOCs of power modules in various conditions.As well as the power supply module can exit the system online

and the exit does not impact the bus voltage.