What the site does
Stuttgart is home to several premium vehicle makers and a dense network of engineering suppliers across Baden-Württemberg. The grading works opened in 2016, the network's first European diagnostics site, and with 28,000 TPA of capacity it remains one of the largest. Its early start means it has tested European pack designs through several generations of technology. Supplier returns are a steady part of its work.
The works focuses on premium passenger-car packs, engineering test and validation packs, and supplier returns. Premium platforms often use complex high-voltage architectures and tightly integrated cooling, so the team's experience with them shortens disassembly time and improves the accuracy of module-level grading. Material below reuse threshold is consolidated and sent to integrated campuses for black mass production, and grade reports are issued for every unit tested.
What arrives at the gate
Feedstock at Stuttgart, Germany reflects its catchment and plant type. Every consignment is weighed, photographed and logged against the originating manifest before it enters the process area.
- Premium passenger-car packs
- Test and validation packs from engineering centres
- Supplier returns from Baden-Württemberg
- Dealer retirements from southern Germany
The process, step by step
The 3 operating lines — module soh bench, eis diagnostics laboratory, ai optical cell grading — run the sequence below.
| Stage | What happens |
|---|---|
| Intake & safety triage | Packs are logged, thermally imaged and screened for swelling, coolant ingress or venting before entering the bench area. |
| Controlled de-energising | Residual energy is discharged to a safe state of charge with regenerative load banks and recorded per serial number. |
| Module-level capacity test | Full charge-discharge cycling at C/3 establishes usable capacity, internal resistance and cell-to-cell balance. |
| EIS fingerprinting | 1 mHz–10 kHz impedance sweeps separate SEI growth, lithium plating and contact resistance degradation modes. |
| AI optical inspection | Machine-vision inspection of busbars, welds and cell cans flags mechanical defects that block second-life reuse. |
| Grade assignment | Grade A (≥85% SOH), B (75–85%), C (65–75%) and D routes are assigned, with D-grade material released to refining. |
What sets the site apart
First European grading site. Operating since 2016, with data across several pack generations.
Premium platform expertise. Experienced with complex high-voltage premium architectures.
Supplier engineering support. Grades returned units so suppliers can understand failure patterns.
Where material goes next
Material that Stuttgart, Germany does not finish on site moves to the nearest specialist facility in the network, keeping transport distances and dwell times down.
| Facility | Role | Distance |
|---|---|---|
| Zwickau — Saxony Second-Life Works | Second-Life BESS Works | 321 km |
| Lyon — Auvergne-Rhone-Alpes Refinery | Hydrometallurgical Refinery | 469 km |
Field note