Synergistic Combination of Cross-Linked Polymer and Concentrated Ionic Liquid for Electrolytes with High Stability in Solid-State Lithium Metal Batteries.

Poly(ethylene oxide)-(PEO-based solid polymer electrolytes (SPEs) are regarded as excellent candidates for solid-state lithium metal batteries (SSLMBs) due to their inherent safety advantages, processability, low cost, and excellent Li+ ion solvation. However, they suffer from limited oxidation stability (up to 4 V vs Li/Li). In this study, a crosslinked polymer-in-concentrated ionic liquid (PCIL) SPE consisting of PEO, -propyl--methylpyrrolidinium bis(fluorosulfonyl)imide (CmpyrFSI) ionic liquid (IL), and lithium bis(fluorosulfonyl)imide (LiFSI) salt is developed.

Poly(Ionic Liquid) Electrolytes at an Extreme Salt Concentration for Solid-State Batteries.

Polymer-in-salt electrolytes were introduced three decades ago as an innovative solution to the challenge of low Li-ion conductivity in solvent-free solid polymer electrolytes. Despite significant progress, the approach still faces considerable challenges, ranging from a fundamental understanding to the development of suitable polymers and salts. A critical issue is maintaining both the stability and high conductivity of molten salts within a polymer matrix, which has constrained their further exploration.

Advanced High-Voltage Electrolyte Design Using Poly(ethylene Oxide) and High-Concentration Ionic Liquids for All-Solid-State Lithium-Metal Batteries.

Poly(ethylene oxide) (PEO)-based solid polymer electrolytes (SPEs) are among the most promising materials for solid-state lithium metal batteries (LMBs) due to their inherent safety advantages; however, they suffer from insufficient room-temperature ionic conductivity (up to 10 S cm) and limited oxidation stability (<4 V). In this study, a novel "polymer-in-high-concentrated ionic liquid (IL)" (PiHCIL) electrolyte composed of PEO, -propyl--methylpyrrolidinium bis(fluorosulfonyl) imide (CmpyrFSI) IL, and LiFSI is designed. The EO/[Li/IL] ratio has been widely varied, and physical and electrochemical properties have been explored.

Understanding Polymerized Ionic Liquids as Solid Polymer Electrolytes for Sodium Batteries.

Solid polymer electrolytes (SPEs) have emerged as promising candidates for sodium-based batteries due to their cost-effectiveness and excellent flexibility. However, achieving high ionic conductivity and desirable mechanical properties in SPEs remains a challenge. In this study, we investigated an AB diblock copolymer, PS-PEA(BuImTFSI), as a potential SPE for sodium batteries.

Exploration of phase diagram, structural and dynamic behavior of [HMG][FSI] mixtures with NaFSI across an extended composition range.

Hexamethylguanidinium bis(fluorosulfonyl)imide ([HMG][FSI]) has recently been shown to be a promising solid state organic ionic plastic crystal with potential application in advanced alkali metal batteries. This study provides a detailed exploration of the structural and dynamic behavior of [HMG][FSI] mixtures with the sodium salt NaFSI across the whole composition range from 0 to 100 mol%. All mixtures are solids at room temperature.

Zwitterionic materials with disorder and plasticity and their application as non-volatile solid or liquid electrolytes.

Zwitterionic materials can exhibit unique characteristics and are highly tunable by variation to the covalently bound cationic and anionic moieties. Despite the breadth of properties and potential uses reported to date, for electrolyte applications they have thus far primarily been used as additives or for making polymer gels. However, zwitterions offer intriguing promise as electrolyte matrix materials that are non-volatile and charged but non-migrating.

Stable High-Temperature Cycling of Na Metal Batteries on NaV(PO) and NaFePO Cathodes in NaFSI-Rich Organic Ionic Plastic Crystal Electrolytes.

Sodium batteries have emerged as a promising alternative for large-scale energy storage applications due to the low cost and high abundance of sodium. Sodium batteries require safe, high-voltage, and cost-effective electrolytes and cathode materials for their practical applications to be realized. In the present study, Na metal cells with a mixed-phase electrolyte comprising a high concentration of Na salt in an organic ionic plastic crystal (OIPC), namely, triisobutylmethylphosphonium bis(fluorosulfonyl)imide, are investigated-coupled with either a sodium vanadium phosphate-carbon composite (NVP/C) or a sodium iron pyrophosphate (NFpP) cathode.