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The development of next-generation batteries relies on addressing critical challenges such as the formation of a robust and stable solid electrolyte interphase (SEI) as well as mitigating lithium dendrite propagation. In this study, we focus on addressing these issues in the preparation of solid polymer electrolytes (SPEs) using poly(ethylene oxide) (PEO) and three different Li-based conductive salts. We investigate the impact of each SPE on the electrochemical performance of solid-state batteries comprising a high-voltage LiNi0.6Mn0.2Co0.2O2 cathode and Li-metal anode. Among the various salts, lithium bis(oxalate)borate (LiBOB) salt stands out, exhibiting a stable voltage profile during charging up to 4.2 V vs. Li/Li+ and preventing the catalytic oxidation of PEO at high-voltage. X-ray photoelectron spectroscopy reveals that LiBOB is reduced into lithium oxalate and other semicarbonate-like species, thereby enhancing the Li metal‖SPE interface from the formation of a dense and stable SEI enriched with LiBOB decomposition products. Our findings underscore the significance of the choice of Li-based salts for forming a stable SEI, which is key for an interfacial engineering design that enables the high-performance of next-generation solid-state batteries. [ABSTRACT FROM AUTHOR]

Self-standing carbon fiber electrodes hold promise for solid-state battery technology owing to their networked structures improving interparticle connectivity, robustness contributing to mechanical integrity, and surface sites confining Li dendrites. We here evaluate carbonized 3D electrospun fibers filled with polymer electrolytes as anodes in solid-state lithium half cells. Microscopic analysis of the cells demonstrates the high wettability of carbon fibers with electrolytes, promoting an intimate contact between electrolytes and fibers. Solid-state cells delivered high initial capacities up to ∼300 mAh g−1, although the latter cycles were characterized by gradual capacity fade (∼100 mAh g−1 in the 100th cycle with nearly 100% coulombic efficiency), attributed to the onset of parasitic reactions increasing the cell resistance and polarization. When these were benchmarked against similar cells but with the liquid electrolyte, it was found that Li storage in these fiber electrodes is intermediate between graphite and hard carbon in terms of lithiation voltage (vs Li/Li+), corroborating with the nature of carbon assessed by XRD and Raman analysis. These observations can contribute to further development and optimization of solid-state batteries with 3D electrospun carbon fiber electrodes. [ABSTRACT FROM AUTHOR]

The main aim of this work is to study the importance of the coupling agent on tensile and thermomechanical performance of annealed composites based on poly (lactic acid)/poly (methyl methacrylate) matrix and sisal fiber bundles. As coupling agent poly (styrene‐co‐glycidyl methacrylate) copolymer was used. Results obtained in the current study suggested that the presence of the copolymer is crucial to form a strong adhesion between the fibers and polymeric matrix and consequently to improve both thermomechanical performance and tensile properties after annealing process. It must highlight that the estimated heat deflection temperature (HDT) of annealed composite with 40 wt% of fiber increased around 40 ºC respect to respect to commercial neat PLA. [ABSTRACT FROM AUTHOR]

The interest on poly(lactic acid) (PLA)/poly(methyl methacrylate) (PMMA) blends has increased during the last years due to their promising properties. The novelty of the current work focuses on the preparation and characterization of biocomposites based on PLA/PMMA matrix and NaOH-treated sisal fibers. The effect of the addition of treated sisal fibers on the physico-mechanical properties of high polylactide content composites was studied. For this purpose, PLA/PMMA blend (80/20 wt%) was prepared by melt-blending and reinforced with different fiber contents. Although composites showed interesting specific tensile properties, the estimated heat deflection temperature (HDT), that is, the maximum temperature at which a polymer system can be used as a rigid material, barely increased 4°C respect to unreinforced system. After the annealing process, the HDT of the unreinforced polymer blend increased around 25°C, whereas the composites showed an increase of at least 38°C. Nonetheless, the specific tensile strength of composite decreased approximately 48% because the adhesion between fiber and polymer matrix was damaged and cracks were formed during annealing process. [ABSTRACT FROM AUTHOR]

High-voltage Li metal solid-state batteries are in the spotlight as high energy and power density devices for the next generation of batteries. However, the lack of robust solid-electrolyte interfaces (SEIs) and the propagation of Li dendrites still need to be addressed for practical application with extended cyclability. In the present work, high-voltage Li metal cells with LiNi0.6Mn0.2Co0.2O2 active material were assembled with a polyethylene(oxide) based electrolyte mixed with lithium bis(fluorosulfonyl)imide (LiFSI) salt. The addition of Li7La3Zr2O12 garnet to form a composite electrolyte demonstrated a beneficial effect for cell cycling stability. Inspired by the improved interface of ceramic Li7La3Zr2O12 garnet and Li metal, as well as by previous knowledge of favorable SEI forming species, various additive candidates were selected to optimize its electrolyte composition. Among them, lithium hydroxide (LiOH) is a key favorable species that shows a relevant improvement in the cyclability of the cells. X-ray photoelectron spectroscopy showed that the SEI layer is composed mainly of chemical species arising from the reduction of the Li salt, with lithium fluoride (LiF) being the main product. In addition, solid-state nuclear magnetic resonance proved that LiOH induces the cleavage of the labile S–F bond, increasing the concentration of LiF. Herein, we highlight that SEI-forming additives need to be considered for the interfacial engineering design of stable SEIs to expand the performance boundary of SSBs. [ABSTRACT FROM AUTHOR]

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The goals of this work are to obtain thermoplastic starch (TPS) with different glycerol/water ratios, verify its characterization by different techniques, and study the influence of addition of cellulose nanofibers in the matrix of TPS. The general procedure for processing starchy materials involves granular alteration with the combination of temperature, shear, and plasticizers. Distilled water and glycerol are used as plasticizers, and the influence of both of them has been studied in tensile properties. By infrared spectroscopy analysis, the addition of plasticizers created new physical links (hydrogen bonds) with starch molecules thereby shifting the characteristic peaks of native corn starch to higher wave number. The most suitable composition for the elaboration of bionanocomposites has been determined and bionanocomposites with different content of cellulose nanofibers have been obtained and their mechanical properties have been studied. [ABSTRACT FROM AUTHOR]