SPP 1473 - Subproject: Thermodynamics and kinetics of lithiation and delithation of high capacity anode materials at elevated temperatures

Basic data for this project

Description

Temperature management is a costly and energy consuming necessity in today’s Li-ion batteries. The majority of organic solvent and gel based electrolytes is instable above 60°C. Since naturally, Li-Ion batteries create thermal energy during discharge, we propose to develop a battery system, which is stable at elevated temperatures (between 60°C and 200°C), applying new electrolytes based on ionic liquids and polymers. Such a system will profit from the waste heat of the battery. Physical features like the ionic conductivity, which are insufficient at room temperature can be elevated to a practical range. Moreover these systemswill allow us studying thermodynamics and kinetics of the lithiation and de-lithiation of high capacity anode materials. A simple system based on the most promising high capacity anode material silicon (with a capacity of 3572 mAh/g, about ten times higher than the 370 mAh/g of Carbon currently in use) will provide the basis to study the impact of elevated temperatures on the formation of Lithium silicide phase during the lithiation and delithiation process. The joint project suggested here will be performed in close cooperation with Prof. Schmidt-Fetzer (Clausthal Zellerfeld) and Prof. Rettenmayr (Jena), who will model the thermodynamic framework and the lithiation- and delithiation-kinetics of Silicon, Carbon or Tin based phases and nanostructures.