BMS Controller Architecture for Second-Life Batteries

As electromobility progresses, there is a growing production of batteries that will eventually require recycling. One potential approach to recycling involves repurposing worn yet still functional batteries into energy storage systems, providing them with renewed functionality. Every battery assembly requires a Battery Management System (BMS), which ensures proper and safe functionality. In the case of recycled cells, the BMS system becomes more intricate due to significant disparities in wear and subsequent parameters among the cells. Second-life batteries extracted from electric vehicles may exhibit various parameters across a single battery pack due to manufacturing tolerances and uneven usage during operation in an electric vehicle. In practice, when using second-life batteries, modules from different electric vehicles of the same model designation are typically utilized. However, if advantageous, modules of different types can also be combined. These facts establish the requirement for a highly universal modular system, which by its nature can cover a wide range of applications of modules of different types and stages of wear. The mentioned module provides a solution to this type of complex problems that cannot be addressed by conventional commercially available products. This paper aims to present the architecture concept and design of the key parts of a universal and flexible BMS control module created based on the requirements arising from the analysis of extended types of second-life battery modules in electric vehicles.