Strategies for rational design of polymer-based solid electrolytes for advanced lithium energy storage applications

• Principals SPEs strategies designs are additives incorporation, polymer matrix structural modification and Li salt progress. • Fundamental bearings of PSEs performance and stability are ion transport mechanism and physicochemical parameters. • Electrode/electrolyte interface behaviour and their role in attaining promising solid electrolytes should be considered. As a result of the increasing need for highly efficient energy storage systems, Li-solid-state batteries emerge as the next-generation energy storage devices to satisfy high energy density and safety requirements. Particularly, solid polymer-based electrolytes have attracted attention as a promising alternative due to their high mechanical flexibility, suitably interfacial compatibility with electrodes, and easy processability, procuring safe, miniaturized and flexible storage devices. Despite the progress made, it is still a challenge to develop low-cost, industrially scalable solid-state batteries with high energy density and stable cycling life. In this context, a review and discussion of recent approaches to polymeric-based electrolyte design for high-performance all-solid-state Li-battery applications are presented. Herein, the latest different design approaches are shown considering: additives incorporation into the polymer matrix, structural modification of the polymer matrix, and lithium salt molecular design. Furthermore, for understanding structure-conduction property relationships in polymer-based electrolytes, the fundamental bearings related to ion transport mechanism, critical parameters involved in the conduction process, and physicochemical aspects related to solid electrolytes performance and stability were analysed. Likewise, significant attention is paid to electrode/ electrolyte interface behaviour and their significance in advanced solid electrolyte designing.