(300a) Molecular Design of Polymer for Solid State Electrolyte Application in Li-Ion Battery: Molecular Modeling Approach

Solid polymer electrolytes (SPEs) have gained considerable attention recently, offering key advantages over liquid electrolytes, such as nonflammability, improved mechanical stability, and minimized electrode material dissolution. In this study, we employ a molecular modeling approach consisting of density functional theory (DFT) and molecular dynamics (MD) simulations to achieve a fundamental understanding of the relationship between the molecular design of polymer and the properties/performances of Li-ion battery application. For this purpose, we investigate the structural and transport properties of carbonate-based SPEs compared to widely used liquid carbonate electrolytes. Specifically, we examine the influence of carbonate pendant group composition on the nanophase morphology of amorphous polycarbonates and Li-ion solvation transport, contrasting them with liquid electrolyte systems like dimethyl carbonate and ethylene carbonate. Furthermore, we investigate how linear versus cyclic carbonate sidechains affect the polymer chain relaxation and the combination of different carbonate pendant group types. This research offers valuable insights for determining the optimal design of polymers to achieve a favorable nanophase morphology and dynamics, enhancing ion transport and mitigating the dissolution of organic cathode materials in the electrolyte.