Classification,Evaluation And Scheduling Strategy Of Retired Power Battery Groups

With the rapid development of new energy automobile industry,the replacement and decommissioning of power batteries lead to a large number of decommissioned power batteries(abbreviated as decommissioned batteries)idle,resulting in energy waste.The use of power batteries step by step has become an effective solution to the problem.Due to the wide application scenario of power batteries,the performance of decommissioned batteries will be inconsistent.Direct use of power batteries will cause problems of low safety and efficiency.Therefore,it is of great significance to study fast and consistent sorting methods for the utilization of decommissioned batteries.At the same time,decommissioned batteries,because of their cost advantages,can provide support for new energy absorption and peak-shaving and valley-filling of power grid.Compared with new batteries,the characteristics of decommissioned batteries are much different.How to optimize the scheduling according to the different characteristics of decommissioned batteries,so that the overall economy of all decommissioned batteries involved in the scheduling is optimal,will be a very meaningful research direction.。 Therefore,this paper mainly studies the sorting,evaluation and optimal scheduling of decommissioned batteries in the process of utilization.The main research of this paper is as follows:(1)A sorting method considering the combination of dynamic and static characteristics of multi-stage and multi-parameters is proposed.For the initial separation of static characteristics,two parameters with the highest contribution rate to static separation are selected to achieve the goal of fast and drastically reducing the number of dynamic characteristics separation.Aiming at the problem of large direct clustering efficiency of dynamic characteristic sorting data,this paper proposes an eigenvalue extraction method based on the phase characteristics of the discharge curve,which achieves the purpose of less feature vector dimension and accurate expression of battery similarity.The results of the example show the effectiveness of the proposed method.(2)An economic evaluation model for single decommissioned battery pack participating in new energy consumption is established.The model not only takes into account the capacity cyclic decay and efficiency decay of decommissioned batteries,but also takes into account the effects of state of charge(SOC)and calendar decay,and establishes a more complete evaluation model.The evaluation index not only evaluates the economy of retired batteries participating in new energy consumption with average income,but also increases capacity utilization rate to evaluate the consistency of retired batteries.The simulation results show that,considering the relationship between calendar attenuation and SOC,the total revenue and average revenue decrease,and the battery evaluation is more perfect.(3)An economic dispatching model for decommissioned batteries with different characteristics is proposed.In the model,the different characteristics of each battery pack are taken into account in the objective function through degradation cost and efficiency loss cost,and the output power of each battery pack is taken as the decision variable to coordinate the dispatch among the batteries.For the dispatch of single batteries in the group,the principle of dispatching according to the discharge time of each battery is proposed,and the hierarchical dispatch from group to single cell is realized.The simulation results show that the optimal dispatching of batteries with different characteristics is more economical.In summary,this paper focuses on the problems in the use of decommissioned batteries.A sorting method considering multi-parameter multi-stage dynamic and static characteristics was proposed and an evaluation model of single-group decommissioned batteries participating in new energy consumption,and an optimized scheduling model of multiple sets of decommissioned batteries with different characteristics were established to achieve the goal of efficient use of decommissioned batteries.This research can provide a basis for the resource utilization and rational utilization of decommissioned batteries.