Background
All-solid-state battery (ASSB) systems containing a solid-state electrolyte (SSE) are widely regarded as Suitable the next-generation battery systems, possibly surpassing conventional lithium-ion batteries containing liquid electrolyte in terms of safety, cycle stability, gravimetric and volumetric energy density, fast charging capabilities and temperature window of operation.
Recently, it has been demonstrated that warm isostatic pressing applied during the fabrication procs of a sulfide-based ASSB has considerable advantages over conventional uniaxial pressing improving cell performance.[1,2] Isostatic pressure is thought of one very promising strategy enabling the fabrication of large-format ASSBs while simultaneously enhancing their electrochemical performance and reducing the need for external pressure during cell cycling. During the assembly of the pouch-cell type ASSB (~0.6 and >5 Ah demonstrator) warm isostatic pressing is applied to laminate and densify electrode and electrolyte sheets. Even with the latest progress, there are still remaining challenges to be addressed by research and development to facilitate consistent production of cells and understand underlying factors affecting cell performance
Task Description/ Scientific questions
- What is the influence of the three main parameters of isostatic processing, on porosity and electrochemical properties in a chosen sulfide solid-state battery reference system? Temperature – Pressure – Holding time
- How is the correlation of impedance with residual porosity and electrochemical performance in a solid-state battery reference system?
- How can material- and electrode design support the isostatic densification process and improve electrochemical performance?
Work included:
- Choice of reference composite system with regards to home institutes “hot topics”
- Synthesis and processing of the reference systems components (Isostatic presses in Quintus Application Center in Sweden, Västerås will be used.)
- Electrochemical and structural characterization of the chosen materials, composite electrodes, and full cells
- Evaluation and interpretation of change in electrochemical characteristics to processing parameter
- Presentation of studies at Quintus Technologies in Västerås, Sweden
Suitable background
Master of Science with specialisation in Material Science, Inorganic Chemistry, Electro-chemistry or similar
Application information
The thesis will take place at the KIT in Karlsruhe, Germany and is expected to start as soon as possible. Send your CV together with grades to timo.rabe@quintusteam.com or florian.strauss@kit.edu. Laboratory preparation of samples will be done at the KIT in Karlsruhe, Germany. Pressing of the samples is done at the test center facility of Quintus Technologies in Västerås, Sweden. Therefore, costs with regards to transportation and accommodation (3-4 trips) will be reimbursed by Quintus Technologies.
For any other questions, please contact:
Business Development Manager, Timo Rabe, timo.rabe@quintusteam.com
Group Leader, Florian Strauss, florian.strauss@kit.edu
Literature Sources:
[1] Y.-G. Lee et al., Nat. Energy 2020, 5, 299-308.
[2] W. Choi et al., ACS Appl. Mater. Interfaces 2024, 16, 20, 26066–26078.
