Claudio Gerbaldi

Single-ion-conducting polymer electrolytes (SICPs) are attractive candidates for all-solid-state lithium-metal batteries because their immobilized anionic groups enable lithium-ion transference numbers approaching unity, thereby suppressing concentration polarization and promoting uniform lithium deposition. However, their widespread application remains limited by insufficient ionic conductivity and the lack of synthetically accessible ionic liquid monomers (ILMs) combining long, flexible spacers with high electrochemical stability. Herein, we report a modular thiol-Michael click strategy for the synthesis of a new family of TFSI-based ILMs incorporating thioether-containing spacers. The proposed approach requires only three reaction steps from readily available starting materials and enables straightforward structural tuning through the selection of commercially available mercapto alcohols. RAFT copolymerization of the resulting ILMs with poly(ethylene glycol) methacrylate, followed by cation exchange, affords a series of SICPs with tunable compositions and properties. The optimized electrolyte exhibits a glass-transition temperature of −45 °C, ionic conductivities of 1.1 × 10−6 and 1.8 × 10−5 S cm−1 at 25 and 70 °C, respectively, a lithium-ion transference number of 0.96, and an anodic stability approaching 5.0 V vs. Li+/Li at 70 °C. Symmetric Li|SICP|Li cells demonstrate stable lithium plating/stripping for more than 1400 h, while all-solid-state Li∥LiFePO4 cells deliver reversible specific capacities of up to 150 and >135 mAh g−1 at C/15 and C/5 rates, with capacity retention over 95% after 200 cycles, and exhibit markedly suppressed lithium dendrite formation compared with previously reported SICPs. These results demonstrate that thioether spacer engineering effectively enhances ion transport while preserving the intrinsic advantages of single-ion conduction, and establish thiol-Michael click chemistry as a simple, scalable platform for next-generation single-ion polymer electrolytes for high-energy lithium-metal batteries.

Local coordination governs the distinct electronic and structural response of each iron center upon Zn ²⁺ intercalation in Berlin green.

Polymer-based electrolytes are increasingly important in advanced batteries because of their structural tunability, mechanical compliance, and compatibility with diverse electrode and cell architectures. Their behavior depends on transport, interfacial, mechanical, and structural processes that span multiple scales and are shaped by formulation and processing history. This Perspective examines how modeling can be applied to polymer-based electrolyte systems in batteries and introduces a framework based on modeling objective, modeling basis, characteristic scale or data level, and degree of process coupling. Battery-relevant ionogel studies are used to map current modeling emphases and underrepresented directions, while polymer-electrolyte-containing composite electrodes illustrate challenges associated with process-generated microstructure and multifunctional polymer phases. Broader gaps are identified in material-state definition, experiment-model information transfer, structural representation, and process coupling. Progress therefore depends not simply on adding isolated models but on developing transparent, experimentally anchored workflows that establish testable links among formulation, processing, structure, transport, and battery-relevant performance.

Bio‐based gel polymer electrolytes (GPEs) are emerging as promising components for rechargeable zinc–air batteries (ZABs), combining electrochemical functionality, mechanical adaptability, and sustainability. Yet, progress in this area is increasingly limited not only by materials design, but also by the lack of rigorous and application‐relevant characterization workflows. This critical, practice‐oriented review assesses the characterization strategies used for bio‐based GPEs in ZABs, focusing on relevant, recent studies reported between 2021 and 2026. Methods are grouped into six categories: mechanical and rheological characterization, electrochemical analysis and cell‐level testing, spectroscopic techniques, microscopy and nanoscale imaging, thermal analysis, and bulk physicochemical characterization. Rather than merely cataloguing methods, the review examines what each technique can reliably reveal, the key parameters controlling data quality, and the limitations imposed by conditions specific to ZAB operation, including highly alkaline environments, dynamic electrode interfaces, and the soft, heterogeneous nature of biopolymer networks. Recurring inconsistencies in experimental practice and reporting are highlighted, and best‐practice recommendations, methodological adaptations, and emerging approaches are discussed. Overall, the review provides a workflow‐oriented framework linking formulation, structure, interfacial behavior, and electrochemical performance, underscoring that better electrolytes require better characterization to enable more rigorous evaluation and accelerate the rational development of next‐generation sustainable GPEs for ZABs.

Self‐standing hybrid solid polymer electrolytes (HSPEs) are herein fabricated through a solvent‐free process, enabling energy‐efficient and industry‐compatible production. The HSPEs are based on a poly(vinylidene fluoride‐co‐hexafluoropropylene) (PVDF‐HFP)/Pyr ₁₄ FSI ionic liquid (IL) system incorporating a small amount of divinyl sulfone (DVS) as a functional additive. This design delivers high ionic conductivity together with excellent mechanical integrity and thermal stability. The IL promotes efficient ion conduction and contributes to thermal stability, while incorporating DVS in little amounts (up to 5%) effectively stabilizes the solid–electrolyte interface (SEI) layer and mitigates degradation processes commonly observed in PVDF‐HFP/Pyr ₁₄ FSI‐based systems. This study presents the first demonstration of a PVDF‐HFP/Pyr ₁₄ FSI‐based electrolyte in which the incorporation of a small amount of DVS enables stable and reversible lithium plating/stripping over 1200 h of continuous cycling at room temperature, with a fixed areal capacity of 0.2 mAh cm ⁻² , in laboratory‐scale solid‐state lithium metal batteries (SSLMB). Furthermore, laboratory‐scale SSLMB cells employing high‐energy NMC811 cathodes exhibit excellent electrochemical performance, delivering specific capacities of 120 mAh g ⁻¹ at C/20 and 100 mAh g ⁻¹ at C/5 under ambient conditions, thereby advancing the development of high‐voltage, intrinsically safe, and high‐performance next‐generation SSLMB technologies.

Asymmetric thioether-TFSI Li salts plasticize PEO SPEs, suppress crystallinity, and retain conductivity, Li ⁺ transference, and stability. They also passivate Al, improving Li-metal compatibility and enabling stable Li∥LiFePO ₄ cycling.