The increasing use of lithium-ion batteries across different scales and applications has made understanding the degradation mechanisms that affect their aging behavior increasingly important. Conditions such as high C-rates, extreme temperatures, and high depth of discharge (DoD) lead to rapid capacity loss, increased internal resistance, and voltage stress at the cell level. In addition, differences in state of charge (SOC) and state of health (SOH) between cells, along with uneven current distribution, result in thermal imbalance and energy losses at the system level. These stress factors further accelerate cell degradation, leading to the development of a reciprocal degradation cycle. This PhD project aims to investigate the interconnection between system and cell degradation by experimental and numerical methods, contributing to the development of stable, safe, and high-performance battery systems under real operating conditions.

Solid-state batteries emerge as a viable alternative to conventional ion-batteries, with their higher safety and energy densities. Despite these promises, solid-state batteries face many challenges to be commercialized. Solid electrolytes have been studied for decades for their ion conductive properties, but little are known about the complex nature of super ionic conductors, especially regarding their transport mechanisms and their processability. This PhD project will focus on unraveling the mechanisms of soft super ionic materials both on the atomic scale but also on the microscopic scale. Understanding how to develop newer materials and how to utilize them in up-scaling