Project 2-4

Monitoring of the cell behavior is a crucial step for the early detection of critical states of a lithium battery. This project seeks to apply thin film sensor structures to lithium-ion batteries for force and temperature monitoring. Charging and discharging processes cause a variation in volume of the active materials in battery cells and lead to forces on the cell housing and the mounting structure of the cells. The objective is to include measurements of the force that a cell exerts on surrounding mechanical structures in the battery management system and the performance evaluation of battery cells made from virgin or recycled materials. Especially for the new generation of solid-state battery systems, precise measurements of the forces affecting the cell are expected to become even more important for determining the performance of a battery system. Together with extensive data mining this allows for a deeper understanding of the cell performance and an assessment of the ageing process of new and recycled materials.

Specific objectives:

• Force measurement setup for precise force monitoring on battery cells
• Selection and characterization of a suitable thin-film sensor system
• Integration of thin-film sensors into measurement setup
• Integration of force measurements into existing battery management models

Expected results:

• Measurement setup including measurement uncertainty estimation and integration into a data mining environment
• Performance evaluation of thin film force sensors for applications in battery cells
• Behavior model for cell force under consideration of different cell types