TOUGH · Toward Tough Amorphous Electrolytes and Stable Interfaces in Solid-State Batteries

Renewable wind and solar energy production and electrification of transport require battery systems to store the electricity until it is needed. Lithium batteries have been very successful, but further improvements are needed in terms of safety, performance, efficiency, cost, and lifetime. The use of solid instead of liquid electrolytes offers a key step forward, but slow kinetics is the Archilles’ heel of solid electrolytes. This problem can be addressed by using amorphous (disordered) instead of crystalline electrolytes, but in turn these suffer from low fracture resistance, compromising long-term performance.In the proposed project, we will elucidate the mechanical behavior of amorphous solid electrolyte/electrode interfaces. The aim is to optimize the electrolyte composition and structure to simultaneously achieve high toughness, stable interfaces, and high lithium ion conductivity. To this end, we will first understand the structure-conductivity relations in disordered and partially ordered sulfide electrolytes (Task 1). Then the mechanical properties of the individual phases and interfaces will be explored in constructed all solid-state batteries (Task 2). These experiments will be complemented by atomistic simulations to understand the structural changes in the investigated systems during battery operation (Task 3).The project builds on complementary expertise of the fellow applicant (battery materials) and supervisor (mechanics, amorphous materials). Together with the research and training environment provided by the host organization (Aalborg University, Denmark), this will ensure the achievement of this timely and innovative project as well as the dissemination and exploitation of the expected results. These research outputs will lead to new amorphous materials that can be integrated in future all solid-state batteries. The fellow applicant will emerge from the project with new skills, and the capability to launch his own research group.