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

Abstract

As the aircraft industry becomes more committed to sustainable aviation, hybrid-electric propulsion systems containing batteries with higher gravimetric energy density attract increasing attention to reduce fuel consumption. Future aircrafts could benefit from next-generation chemistries like oxide-based all-solid-state Li-battery (ASSB) technologies. However, producing and evaluating a wide range of design parameters for maximising the gravimetric energy density of ASSB experimentally is both time- and resource-intensive. Physics-based modelling promises to identify optimal designs for battery cells with respect to high gravimetric energy density more time and cost-efficient. In this regard, we applied a pseudo-two-dimensional model for the model-based evaluation of Li-ASSB with various hybrid electrolytes containing oxide and polymer electrolytes. This way we elucidate which electrolyte performs well with present technology and which has the potential to become an attractive alternative in the future. After identifying design variables to improve ASSB with the help of sensitivity analysis, a genetic algorithm is used to predict the optimal design parameters to achieve higher gravimetric energy density. The conducted study reveals that ASSB based on 12.7 vol% of garnet Li6.4La3Zr1.4Ta0.6O12 (LLZTO) is the best option based on present manufacturing constraints. Hybrid electrolytes based on 10 wt% of Li1.3Al0.3Ti1.7(PO4)3 (LATP) could be promising for future aircrafts with further improvements in ASSB manufacturing process.