Material-adapted Gripping and Handling of PEO-based Cell Components for All-Solid State Battery Cell Stacking

Lithium-ion batteries (LIBs) immensely contribute to the electromobility’s success for achieving climate change goals. As LIBs are forecasted to succumb to optimization limits in the coming decade, next generation battery technologies, such as all-solid-state batteries (ASSBs), gain noteworthy attention for meeting ever-increasing cell performance requirements. By deploying solid electrolytes (SEs), compared to liquid electrolytes in current LIBs, ASSBs benefit from enhanced safety against flammability and allow for the usage of lithium metal anodes for higher energy densities. Here, polymer solid electrolytes, such Polyethylene oxide (PEO), are widely used for their high flexibility and hence beneficial processability properties compared other SEs. However, their adhesive behavior poses challenges when conducting handling and stacking processes with conventional grippers during cell assembly. In this research, we present a parameter study on ASSB handling and stacking with PEO-based cell components aiming to promote process understanding and point out optimization potentials. An experimental design for testing different grippers is devised by which deposition accuracy was systematically assessed in relation to the holding force, gripper speed, and placement distance. Within this evaluation, the electrostatic gripper with PTFE dielectric provides adequate position and orientation accuracies in almost all experiments while showing improved accuracies with higher holding forces. Parameter settings achieving higher overall deposition accuracies for all tested grippers are identified. This research provides insights into the establishment of stacking processes for realizing an industry-scale ASSB production.