Fraunhofer Research Institution for Battery Cell Production FFB 
SmartBMS
Research Project: “Smart Battery Management System and Intelligent Data Analysis in the Cell Production Process”
The research project SmartBMS aims to integrate the innovative process of eta leveling into battery management systems (BMS) and comprehensively validate its potential for increasing production and operational efficiency in the context of battery cell production. Eta leveling aims to optimize the charging process by specifically compensating for differences in the charging and discharging performance of individual battery cells. The project also aims to determine the maximum permissible tolerance window extensions in battery cell production. This will be achieved through the detailed development of a cause-and-effect model. An expansion of the tolerance window leads to an increase in the efficiency and cost-effectiveness of production, as products are not prematurely defined as rejects.
Another goal is the development of an Eta box with a special charging algorithm and, in addition, the development of a demonstrator that can be connected to a BMS and thus compensate for SoC losses of cells in battery modules. Since modern battery systems play a central role in a wide range of applications such as electric vehicles, renewable energies, and mobile devices, the precise coordination of the individual cells is crucial to ensure optimal performance and longevity.
Work schedule
The work plan consists of six work packages:
AP1 Validation of Eta leveling and analysis of possible discrepancies between cells on lab scale: AP1 validates the feasibility and efficiency of Eta leveling in the laboratory, examines its influence on cell lifespan and stability, determines compensable quality differences between A- and B-grade cells, and defines the physical and algorithmic limits of application.
AP2 Data structuring and evaluation for cause-and-effect identification: AP2 implements data acquisition and traceability, develops and validates a data-based cause-and-effect model of critical process parameters, and statistically analyzes existing tolerance windows to derive recommendations for their expansion.
AP3 Evaluation of production efficiency: AP3 tests gradually expanded tolerance windows in real production campaigns and records the measured product and production parameters. Based on this, effects on efficiency and quality are evaluated and concrete process optimizations are derived.
AP4 Development of the Eta Box with Matlab module: AP4 develops the MATLAB-based software architecture for the adaptive cell compensation process, integrates it into a scalable hardware housing, and combines both into a functional demonstrator.
AP5 System integration and validation of system lifetime/performance and cost savings: AP5 integrates all hardware and software components, tests lifetime, thermal stability, and performance in extensive test scenarios, and creates a cost model that quantifies potential savings through reduced waste and extended system lifetime.
AP6 Project management and broad transfer: AP6 coordinates deadlines, reporting and financial controlling, and risk management as part of overall project management, ensures internal and external communication, and prepares the project results for target groups in science, industry, and politics.
Utilization of results
SmartBMS will demonstrate that adaptive Eta leveling is technically feasible and demonstrably improves cell voltage homogeneity and the service life of lithium-ion systems. Based on a modular data framework, data-driven cause-and-effect models are created that can be used to identify critical process parameters and extend manufacturing tolerances without compromising product quality. Production campaigns at FFB PreFab validate these expanded tolerance windows under real-world conditions, and a MATLAB-based Eta Box demonstrator device proves the practicality of the developed hardware and software components. Accompanying cost modeling provides reliable figures on potential savings through reduced scrap rates and the economical use of B-grade cells.
The insights gained are not only relevant for the project partners involved, but also offer the potential to be used throughout the battery industry. This is particularly true for companies involved in the series production of battery cells, as the developed technologies enable significant savings through extended tolerance windows. Similarly, the innovative Eta leveling algorithms can be transferred to BMS systems in electromobility, stationary energy storage systems, and hybrid battery architectures. There, the research results will contribute to longer lifetimes for storage systems, thus enabling a more sustainable use of resources. The project thus increases the innovation and competitiveness of the industry and contributes to a sustainable, technologically advanced future.
