**4. Results and Discussion**

*4.1. Case Study*

The Audi A3 Sportback e-tron hybrid Li-ion battery pack was chosen as the use case in this paper to demonstrate our approach to planning disassembly strategies for battery systems. The selected battery was described in detail by Alfaro-Algaba and Ramirez [14]. The selected disassembly steps are presented, and most of the data required for our proposed disassembly strategy optimization method are available. The relevant assumptions for our use case are listed below:



**Table 1.** Throughput of a disassembly station and overhead costs.

In the following, we consider two scenarios for disassembly planning of the considered battery. The upper and lower housing shells and the cooling plates are in poor condition in the first scenario and can, therefore, only be recycled. In the second scenario, they can be assigned to all possible circular economy strategies. The eight modules are in different conditions: two modules must be recycled (CESi = 4), two modules can be reprocessed for second-life applications (CESi = 3), such as stationary energy storage, two modules can be remanufactured for automotive applications (CESi = 2), and the last two modules can be directly reused in the automotive sector with little effort, for example for cleaning and packaging (CESi = 1). In addition, we assume that all connecting elements cannot be reused and consequently have to be recycled in both scenarios. All other components of the considered have the same condition in both scenarios; see the condition vectors of both scenarios in Equations (3) and (4).

$$\mathbf{S}\_1^T = [4\ 4\ 1\ 1\ 1\ 1\ 1\ 1\ 1\ 1\ 4\ 4\ 4\ 4\ 4\ 1\ 1\ 2\ 2\ 3\ 3\ 4\ 4\ 4\ 4\ 4\ 4\ 4\ 4\ 4\ 4\ 4\ 4]\tag{3}$$

$$\mathbf{S}\_2^T = [1\ 4\ 1\ 1\ 1\ 1\ 1\ 1\ 1\ 1\ 1\ 4\ 4\ 1\ 1\ 1\ 2\ 2\ 3\ 3\ 4\ 4\ 4\ 4\ 4\ 4\ 4\ 4\ 4\ 4\ 4\ 4]\tag{4}$$

**Figure 10.** Li-ion battery of the Audi A3 Sportback e-tron hybrid: disassembly precedence graph and disassembly times at the component level. The disassembly times are specified by the following format: x[number of units]; [disassembly time per unit]; [total disassembly time].
