Latest Updates
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Understanding Solvation Behavior of the Saturated Electrolytes with Small/Wide-Angle X-ray Scattering and Raman Spectroscopy
A combined SAXS/WAXS and Raman spectroscopy are employed to study the global and local solvation structure. This work demonstrates a method for detecting the structure of liquids, which will facilitate the study of structure-performance relationships and the screening of new electrolytes. Read More
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Pulsed Field Gradient Nuclear Magnetic Resonance and Diffusion Analysis in Battery Research (Review)
A pedagogical overview of Pulsed Field Gradient Nuclear Magnetic Resonance (PFG-NMR) analysis for battery electrolytes provides a guide for new and seasoned practitioners, while demonstrating the many uses of diffusion measurements through a review of selected examples. Read More
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Multiple charging of tripodal catholyte redoxmers
Redox-active oligomer molecules can become more (100x) stable when they are fully charged compared to their partially charged states. This is the first time this effect was observed in chemistry. Read More
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Combining electrochemical and imaging analyses to understand the effect of electrode microstructure and electrolyte properties on redox flow batteries
Through a combined experimental and modeling approach, we show that, of the many physical properties associated with fibrous electrodes, permeability best correlates with electrochemical performance in a flow cell. Read More
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Role of Multivalent Ion – Solvent Interaction on Restricted Mg2+ Diffusion in Dimethoxyethane (DME) Electrolytes
Comparison of the diffusion behaviors of Mg2+, TFSI-, DME, and Li+ reveals a relative restriction to Mg2+ diffusion that is caused by the long-range interaction between Mg2+ and solvent molecules, especially those with suppressed motions at high concentrations and low temperatures. Read More
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Tabc Li+ in Sulfolane-and Tetraglyme-based Electrolytes by Very Low Frequency Impedance Spectroscopy (VLF-IS)
A systematic study of the effect of concentration on Li+ transference number under anion-blocking conditions (_(〖〗^+)^) in sulfolane (SL) and tetraglyme (G4) using VLF-IS showed that SL is a more superior solvent than G4 for Li+ transport, even though the viscosity of the former is higher but with similar ionic conductivity. Read More
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Cross-Platform Classifier for Electrochemical Stability
Predicting electrochemical stability of redox-active molecules is needed to achieve durable flow batteries for electric grid storage. Here, Sure Independence Screening and Satisfying Operator (SISSO) is used to construct a binary classifier for predicting chemical stability of charged organic molecules. SISSO is an artificial intelligence (AI) expert that derives and tests heuristic algebraic formulas to rationalize data trends. Two unrelated families of redox-active molecules were classified by the same empirical parameter, which is a nonlinear combination of molecular descriptors found by SISSO without human guidance. Read More
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JCESR-supported research makes cover of Science: New electrolyte bolsters rechargeable battery design
This press release was authored by the A. James Clark School of Engineering, University of Maryland. The energy contained within lithium-ion batteries has the potential to reshape the technology of the future battlefield, creating a worldwide demand for key lithium-ion battery materials… Read More
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Discovery of Energy Storage Materials Using Multi-objective Bayesian Optimization
Designing optimal materials for redox flow batteries is challenging due to the multi-criteria requirement and large number of potential candidates. Multi-objective Bayesian optimization (MBO) was developed and demonstrated to significantly accelerate (15-fold) the identification of anolyte molecules of desired reduction potential, solubility, and fluorescence from a large chemical space. Read More
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Understanding the transient ion transport behavior at phase transition temperatures
In this work we clarified a fundamental question of high importance but often neglected: how the ion transport behavior of electrolytes change during phase transition. The quantitative understanding of such transient behavior has profound impact on how to accurately define and predict electrolyte applications in extreme environments. Read More
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Critical Role of Structural Order in Bipolar Redox‐Active Molecules for Organic Redox Flow Batteries
Bipolar redox-active molecules have been suggested as a means to address crossover related issues in all-organic redox flow batteries. The present work describes a fundamental rubric to uncover the likely origins in the performance metrics of these bipolar molecules that are salient for their use in redox flow batteries. Read More
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Counterion-dependent charge transport in viologens
Our results show that charge transport in viologens critically relies the electrochemical environment and is particularly sensitive to the electrolyte counteranion. We use an electrochemical gating technique to understand charge transport in viologens as a function of the redox state and electrochemical environment. Molecular modeling shows that differences in charge transport arise from counterion-induced variations in molecular geometries. Read More
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Quantifying and Suppressing Proton Intercalation to Enable High-Voltage Zn-Ion Batteries
The relative contributions of Zn2+ and H+ insertion to the overall capacity of VPO4F are differentiated and quantified in aqueous and hybrid electrolytes. Increasing the salt concentration and/or proportion of nonaqueous solvent successfully suppresses water dynamics, improving the anodic stability and promoting Zn2+ intercalation over competing processes. Read More
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Highly efficient charge transport at molecule-electrode interfaces
Our results show that resonant transport offers a highly efficient intramolecular charge transport mechanism that will enable long-range transport in electronic devices. We further develop a general quantitative relation to describe the non-resonant to resonant transition voltage VT as a function of molecular properties. Read More
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Toward Unraveling the Origin of Lithium Fluoride in the Solid Electrolyte Interphase
We revealed the origin of LiF in the solid electrolyte interphase (SEI) using a multimodal experimental and theoretical approach and found that LiF nucleated via the electrocatalytic transformation of HF followed by significant direct anion reduction. Read More
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Temperature Dependence of Ion Transport Properties in PEO Electrolytes
We measured the temperature dependence of ion transport properties in PEO/LITFSI electrolytes across a range of salt concentrations. Using these results, we were able to predict how concentration polarization changes with temperature. Read More
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Water or Anion? Zn2+ Solvation Environment in Mixed Zn2+/Li+ Water-in-Salt Electrolytes
Zn2+ cations are mainly solvated by six waters in their first solvation shell, while TFSI- anions are excluded from solvation in the WISE electrolyte consisting of 1 m Zn(TFSI)2 and 20 m LiTFSI although the TFSI- concentration is as high as 22 m. Read More
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Ion Transport in Block Copolymer Electrolyte Affected by Distortion of Lamellae Domains under DC Polarization
We studied the structure of block copolymer electrolyte using small-angle X-ray scattering (SAXS) during direct current (dc) polarization and observed the distortion of the lamellae domain spacing d to accommodate the salt concentration gradient. Read More
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Simultaneously Enhancing the Redox Potential and Stability of Multi-Redox Organic Catholytes by Incorporating Cyclopropenium Substituents
High redox potential, two-electron organic catholytes for non-aqueous redox flow batteries were developed by appending diaminocyclopropenium (DAC) substituents to phenazine and phenothiazine cores. Read More
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In situ/operando soft x-ray spectroscopy of chemical interfaces in gas and liquid environments
In situ/operando soft x-ray spectroscopy characterizations of interfacial phenomena reveal the mechanism of charge transfer and chemical transformations of solid/gas and solid/liquid interfaces of energy storage and catalytic materials in realistic environments. The unique design of the instrumentation, the fabrication principle and examples of experiments are presented. Read More