Using retired batteries to construct a grid energy storage system can make full use of their residual value. This is an important way to solve the problem of reusing a large number of retired batteries. However, because they have been charged and discharged many time, there is an inconsistency problem that is more prominent than that with new batteries. First, a reconfigurable hierarchical balancing topology for retired batteries is proposed. Secondly, a hierarchical balanced control strategy is proposed based on this topology. Two levels of equalization control, i.e. intra- and inter-group are considered. SOC and terminal voltage are used as balancing variables within the group to achieve single cell state equalization through reconfiguration. SOC is used as a balancing variable between groups to ensure whole cell cluster equalization through reconfiguration. It simultaneously considers different operating conditions: balancing efficiency and usable capacity of battery packs is increased by self-equalization in static balancing. The output voltage stability is maintained by topology transformation in the discharging process. Charging current is reasonably optimized considering energy loss and charging speed in the charging process to shorten the charging time, reduce the temperature rise and improve service life. Finally, the effectiveness of the proposed topology and strategy in different operating conditions is verified in Matlab.