2.2.1. Database

The appropriate disassembly strategy for an individual EVB is the result of an optimization problem under consideration of a wide range of data, which must be available to the disassembly factories in order to increase the efficiency of a circular economy for battery systems. Therefore, structuring and managing these data in a database is of fundamental importance. Thereby, the need-based availability of some information is essential to protect the competitive advantages of battery manufacturers. Relevant data can be divided into process-related data and product-related data. Process-related data are, for example, disassembly times and costs and needed disassembly tools. The product-related data can be further classified into master data, transaction data, status data, and market data [24]. Master data comprise general information about the battery, such as the cell format and chemistry, the number of cells and modules, and information about other battery components, such as the battery management system. For disassembly, the precedence constraints, the joining techniques, the position of parts, and information about their accessibility are particularly important. Transaction data include information about the history of the battery. Status data provide information about the condition of the different components of the battery, such as the state of health of the modules and the cells. Market data are also essential to find out the optimal disassembly strategy. In particular, the potential revenues from selling components after applying a specific EoL strategy, such as remanufacturing, play a role.

#### 2.2.2. Sensorial System

Before disassembly, the information from the database can be expanded with additional data using other sources, such as battery measurements or employees' experience. Nevertheless, not all the information may be available before starting the process. This is due to the variety of uncertainties during automated disassembly. Therefore, the sensorial system in an automated disassembly solution is mandatory to plan the process and to adapt it at the operational level [21]. Thereby, a vision system is needed to detect the components and their positions and monitor the progress of the disassembly process. In addition, other sensors are required, such as torque and force sensors, which can be used for both process control and monitoring.
