Model-Based Design of High Energy All-Solid-State Li Batteries with Hybrid Electrolytes

As the aircraft industry becomes more committed to sustainable aviation, hybrid-electric propulsion systems containing batteries with higher specific energy have attracted attention as a means to reduce fuel consumption. Future aircraft could benefit from next-generation chemistries like oxide-based solid-state Li battery (SSB) technologies. However, producing and evaluating a wide range of design parameters for maximizing the specific energy of SSB experimentally is both time- and resource-intensive. Physics-based modeling promises to identify optimal designs for battery cells with respect to high specific energy in a more time and cost-efficient manner. Here, we applied a pseudo-two-dimensional model for the model-based evaluation of Li-SSB with various (hybrid) electrolytes to elucidate which solid electrolyte performs well with present electrode technology and which one has the potential to become an attractive alternative with more development. After identifying design variables to improve SSB with the help of sensitivity analysis, a genetic algorithm is used to predict the optimal design parameters to achieve higher specific energy. The study reveals that SSB based on 12.7 vol% of LLZTO is the best option under present manufacturing constraints. Hybrid electrolytes based on 10 wt% of LATP could be promising for future aircraft with further improvements in SSB manufacturing process.