An Fuqiang, Zhao Hongliang, Li Ping
Institute for Advanced Materials and Technology, University of Science and Technology Beijing Beijing China
RSC Adv. 2018 Aug 31;8(54):30802-30812. doi: 10.1039/c8ra05403g. eCollection 2018 Aug 30.
More than two parameters are adopted to sort the lithium ion cells (LICs) for better performance in the production process, such as capacity, open-circuit voltage (OCV), direct current resistance (DCR), However, more sorting parameters make mass production more complex. In order to solve this conflict, we compare capacity, OCV, DCR, and self-discharge rate ( ) in this paper, investigate their different effects on the cycle life of parallel LICs through analyzing the relationship between component cell variations and the durability of the parallel blocks. We find that the variations of the self-discharge rate in cells significantly affect the discharge capacity retention of the blocks: bigger variation in the cells results in a better cycle life of parallel LICs. Thus, it is prudent to perform cell sorting for the assembly of superior blocks based on the self-discharge rates of the cells.
在生产过程中，采用了两个以上的参数对锂离子电池（LIC）进行分选，以实现更好的性能，如容量、开路电压（OCV）、直流电阻（DCR）等。然而，更多的分选参数会使大规模生产变得更加复杂。为了解决这一矛盾，我们在本文中对容量、OCV、DCR和自放电率（ ）进行了比较，通过分析单节电池变化与并联电池组耐久性之间的关系，研究它们对并联LIC循环寿命的不同影响。我们发现，电池自放电率的变化显著影响电池组的放电容量保持率：电池中较大的变化会导致并联LIC的循环寿命更好。因此，基于电池的自放电率对电池进行分选以组装优质电池组是明智的。
