(102b) 3D Printing of Surface Structure Reinforced Poly(ethylene glycol) Diacrylate (PEGDA) Electrolytes for All-Solid-State Li-S Batteries

Solid-state batteries are a key step in producing the next generation of high energy storage systems. Currently, all-solid-state-batteries (ASSB) are burdened with diminished ionic conductivity and poor interfacial contact between the solid-state electrolyte and the electrode materials leading to higher resistances and poor electrochemical performance. 3D printing has emerged as a promising solution to the poor interfacial contact between electrolyte and electrode materials, owed to the intricacies the technique affords to the engineering of surfaces. Specifically, 3D printing is capable of developing precise structures at the milli, micro, and now nano scale. By using advanced stereolithography, solid poly(ethylene glycol) diacrylate (PEGDA) based polymer electrolytes can be designed with different surface structures (i.e. concentric circles, parallel ridges, waffle structures, among others) that increase the interfacial contact area between the polymer matrix and electrodes. Employed novel surface structures on polymer electrolytes as a host for cathode materials allowed for improved interfacial contact and increased loading of active materials. The cathode/electrolyte interface will be characterized by SEM and TEM to gain a better understanding of the composition at the interfacial layer pre and post cycling. Assembled cells using 3D-printed electrolytes show improved room temperature cyclability and specific capacities in Li-S batteries. The findings of this work will gain a better understanding of 3D printed structures on the electrochemical performance, and lead to a rational design of solid electrolytes for the next generation of Li-S batteries.