Sodium Polymer Electrolytes: A Review

Abstract

Lithium-based electrolytes are, at least from a thermodynamic standpoint, the most suitable ion-transport materials for energy storage systems. However, lithium-based ionic conductors suffer from safety concerns, and the limited availability of lithium in the Earth’s crust is at the root of the need to consider alternative metal ions. Notably, sodium stands out as the sixth most-prevalent element; therefore, when considering mineral reserves, it as a very attractive candidate as an alternative to the status quo. Even if the specific energy and energy density of sodium are indeed inferior with respect to those of lithium, there is substantial economic appeal in promoting the use of the former metal in stationary energy storage applications. For these reasons, the promise of sodium is likely to extend to other commercial applications, including portable electronics, as well as hybrid and electric vehicles. Widely used organic liquid electrolytes, regardless of their chosen metal cation, are disadvantageous due to leakage, evaporation, and high flammability. Polymer electrolytes are acknowledged as the most effective candidates to overcome these obstacles and facilitate the advancement of next-generation energy storage applications. In this contribution, an in-depth and comprehensive review of sodium polymer electrolytes for primary and secondary batteries is proposed. The overarching goal was to gain insight into successful synthetic strategies and their implications for conduction parameters and conductivity mechanisms. The focus lies on solid, gel, and composite polymer electrolytes. Our hope is that the proposed discussion will be helpful to all operators in the field, whether in tackling fundamental research problems or resolving issues of practical significance.

ARGET-ATRP-Mediated Grafting of Bifunctional Polymers onto Silica Nanoparticles Fillers for Boosting the Performance of High-Capacity All-Solid-State Lithium–Sulfur Batteries with Polymer Solid Electrolytes

“…This seemingly promising cathode material simultaneously gives rise to the aforementioned issues on both the cathode and anode, resulting in rapid capacity decay of Li-S batteries. The development of all-solid-state Li-S batteries holds tremendous potential for the commercialization of Li-S battery technology [ 16 , 17 , 18 , 19 , 20 ]. Solid polymer electrolytes (SPEs) can play a crucial role by acting as physical barriers, effectively controlling the dissolution of LiPSs from the cathode and mitigating their negative impact on the anode [ 18 , 21 , 22 , 23 , 24 ].…”

“…The development of all-solid-state Li-S batteries holds tremendous potential for the commercialization of Li-S battery technology [ 16 , 17 , 18 , 19 , 20 ]. Solid polymer electrolytes (SPEs) can play a crucial role by acting as physical barriers, effectively controlling the dissolution of LiPSs from the cathode and mitigating their negative impact on the anode [ 18 , 21 , 22 , 23 , 24 ]. Additionally, SPEs offer a range of advantages, such as preventing electrolyte leakage, enabling high energy density, and enhancing safety [ 24 , 25 , 26 ].…”