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Abstract Sulfide solid-state electrolytes (SSEs) are promising candidates to realize all solid-state batteries (ASSBs) due to their superior ionic conductivity and excellent ductility. However, their hypersensitivity to moisture requires processing environments that are not compatible with today’s lithium-ion battery manufacturing infrastructure. Herein, we present a reversible surface modification strategy that enables the processability of sulfide SSEs (e. g., Li₆PS₅Cl) under humid ambient air. We demonstrate that a long chain alkyl thiol, 1-undecanethiol, is chemically compatible with the electrolyte with negligible impact on its ion conductivity. Importantly, the thiol modification extends the amount of time that the sulfide SSE can be exposed to air with 33% relative humidity (33% RH) with limited degradation of its structure while retaining a conductivity of above 1 mS cm^-1for up to 2 days, a more than 100-fold improvement in protection time over competing approaches. Experimental and computational results reveal that the thiol group anchors to the SSE surface, while the hydrophobic hydrocarbon tail provides protection by repelling water. The modified Li₆PS₅Cl SSE maintains its function after exposure to ambient humidity when implemented in a Li_0.5In | |LiNi_0.8Co_0.1Mn_0.1O₂ASSB. The proposed protection strategy based on surface molecular interactions represents a major step forward towards cost-competitive and energy-efficient sulfide SSE manufacturing for ASSB applications. 

Abstract The concept of employing highly concentrated electrolytes has been widely incorporated into electrolyte design, due to their enhanced Li‐metal passivation and oxidative stability compared to their diluted counterparts. However, issues such as high viscosity and sub‐optimal wettability, compromise their suitability for commercialization. In this study, we present a highly concentrated dimethyl ether‐based electrolyte that appears as a liquid phase at ambient conditions via Li⁺‐ solvents ion‐dipole interactions (Coulombic condensation). Unlike conventional high salt concentration ether‐based electrolytes, it demonstrates enhanced transport properties and fluidity. The anion‐rich solvation structure also contributes to the formation of a LiF‐rich salt‐derived solid electrolyte interphase, facilitating stable Li metal cycling for over 1000 cycles at 0.5 mA cm⁻², 1 mAh cm⁻²condition. When combined with a sulfurized polyacrylonitrile (SPAN) electrode, the electrolyte effectively reduces the polysulfide shuttling effect and ensures stable performance across a range of charging currents, up to 6 mA cm⁻². This research underscores a promising strategy for developing an anion‐rich, high concentration ether electrolyte with decreased viscosity, which supports a Li metal anode with exceptional temperature durability and rapid charging capabilities. 

Antimicrobial de-escalation refers to reducing the spectrum of antibiotics used in treating bacterial infections. This strategy is widely recommended in many antimicrobial stewardship programs and is believed to reduce patients’ exposure to broad-spectrum antibiotics and prevent resistance. However, the ecological benefits of de-escalation have not been universally observed in clinical studies. This paper conducts computer simulations to assess the ecological effects of de-escalation on the resistance prevalence ofPseudomonas aeruginosa—a frequent pathogen causing nosocomial infections. Synthetic data produced by the models are then used to estimate the sample size and study period needed to observe the predicted effects in clinical trials. Our results show that de-escalation can reduce colonization and infections caused by bacterial strains resistant to the empiric antibiotic, limit the use of broad-spectrum antibiotics, and avoid inappropriate empiric therapies. Further, we show that de-escalation could reduce the overall super-infection incidence, and this benefit becomes more evident under good compliance with hand hygiene protocols among health care workers. Finally, we find that any clinical study aiming to observe the essential effects of de-escalation should involve at least ten arms and last for four years—a size never attained in prior studies. This study explains the controversial findings of de-escalation in previous clinical studies and illustrates how mathematical models can inform outcome expectations and guide the design of clinical studies. 

Abstract Processes of magma generation and transportation in global mid‐ocean ridges are key to understanding lithospheric architecture at divergent plate boundaries. These magma dynamics are dependent on spreading rate and melt flux, where the SW Indian Ridge represents an end‐member. The vertical extent of ridge magmatic systems and the depth of axial magma chambers (AMCs) are greatly debated, in particular at ultraslow‐spreading ridges. Here we present detailed mineralogical studies of high‐Mg and low‐Mg basalts from a single dredge on Southwest Indian Ridge (SWIR) at 45°E. High‐Mg basalts (MgO = ∼7.1 wt.%) contain high Mg# olivine (Ol, Fo = 85–89) and high‐An plagioclase (Pl, An = 66–83) as phenocrysts, whereas low‐Mg basalts contain low‐Mg# Ol and low‐An Pl (Fo = 75–78, An = 50–62) as phenocrysts or glomerocrysts. One low‐Mg basalt also contains normally zoned Ol and Pl, the core and rim of which are compositionally similar to those in high‐Mg and low‐Mg basalts, respectively. Mineral barometers and MELTS simulation indicate that the high‐Mg melts started to crystallize at ∼32 ± 7.8 km, close to the base of the lithosphere. The low‐Mg melts may have evolved from the high‐Mg melts in an AMC at a depth of ∼13 ± 7.8 km. Such great depths of magma crystallization and the AMC are likely the result of enhanced conductive cooling at ultraslow‐spreading ridges. Combined with diffusion chronometers, the basaltic melts could have ascended from the AMC to seafloor within 2 weeks to 3 months at average rates of ∼0.002–0.01 m/s, which are the slowest reported to date among global ridge systems and may characterize mantle melt transport at the slow end of the ridge spreading spectrum.