Options
2021
Conference Paper
Titel
Scale-up of mechanochemical synthesis of sulfide-based solid electrolytes for all-solid-state batteries
Abstract
Over the last years all-solid-state batteries (ASSB) are increasingly considered as promising follow-up technology of conventional lithium-ion batteries due to their potentially superior properties [1,2]. In order to produce cells with competitive characteristics, such as high energy density as well as high thermal and mechanical stability, the choice of materials at the beginning of the value-added chain is a main key. Currently, there are still challenges for upscaling the synthesis and processing routes of solid electrolytes (SE) wherefore ASSB have been just established at the laboratory scale. Bearing this aspect in mind, the focus of this work was to evaluate and establish new scalable process strategies to produce SE. Thiophosphates have attracted broad interest as SE because of their high Li+ conductivity and compliant mechanical properties [3]. Within this work, their synthesis was performed via high energy ball milling. Mechanochemical syntheses are typically known as scalable but time consuming processes [4]. In this work process time for the syntheses of Li3PS4 and Li6PS5Cl could be highly reduced to a few hours by the systematic variation and optimization of operational parameters. Moreover, a deeper understanding of process-structure-product-relations was gained. In Addition, the simulation of the process with the discrete-element-method (DEM) gave insights into the stressing conditions. The coupling of the experimental and simulation results reveals a direct correlation between the existing stressing conditions for different parameter sets and the obtained product properties. In a next step, the identified stressing conditions can be transferred to DEM models of scalable mill types such as stirred media mills to get indications for required operational parameters. Based on the obtained insights, the synthesis procedure was successfully demonstrated in a upscaled mill type, which will thus facilitate the industrial production of ASSB.