Research Highlights
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Improving Continuum Models to Define Practical Limits for Molecular Models of Electrified Interfaces
Scientific Achievement We develop a self-consistent methodology for modeling biased interfaces that combines (i) continuum theory and (ii) ab initio molecular dynamics, to explore the structure of the electric double layer under various electrochemical conditions, including effects of electron transfer and non-electrostatic interactions (e.g. Read More
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Predicting the Potentials, Solubilities and Stabilities of Metal-Acetylacetonates for Non-Aqueous Redox Flow Batteries Using Density Functional Theory Calculations
Density functional theory (DFT) was used to calculate key materials properties that were correlated with experimentally determined parameters that define the performance of redox flow battery (RFB) active materials. These include standard potentials, solubilities, and importantly stabilities. The correlations are for metal-acetylacetonate (acac) complexes, a promising class of actives, but could also be used for other materials. Read More
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Study of Li Intercalation into α-V2O5 Nanowires using in situ Transmission Electron Microscopy
We examine the effects of Li intercalation into α-V2O5 nanowires using in situ transmission electron microscopy. Combining electron diffraction and electron energy loss spectroscopy, we conclude that the pristine V2O5 nanowires form a Li2O shell, which acts as a solid state electrolyte. Thus Li+ ions move radially into the nanowire core, and bulk of the nanowire undergoes transformation to the γ-Li2V2O5 phase at -1.3 V bias. Read More
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“Wine-Dark Sea” in an Organic Flow Battery: Storing Negative Charge in 2,1,3-Benzothiadiazole Radicals Leads to Improved Cyclability
Scientific Achievement 2,1,3-benzothiadiazole (BzNSN) was identified as a promising anolyte molecule for non-aqueous organic redox flow batteries. A proof-of-principle 2.36 V nonaqueous organic flow battery was developed by coupling BzNSN with DBMMB. Relatively stable performances over extended cycling were demonstrated under tested flow cell conditions,… Read More
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Mono vs Divalent Cation Diffusion in Thiospinel Ti2S4
We showed why the positive electrode material, MgxTi2S4, does not work well at room temperature, unlike Li2xTi2S4, which works very well. Furthermore, we confirmed that theoretical diffusion calculations predict accurate results at low x values. Read More
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Elucidating the Solvation Structure and Dynamics of Lithium Polysulfides
A coupled theoretical and experimental study of bulk solvation structure and transport properties of lithium salt (Li-TFSI) and polysulfides species revealed extensive cluster formation in lower order polysulfides (Sx2-; x≤4), whereas the longer polysulfides (Sx2-; x>4) show high solubility and slow dynamics in the solution. Read More
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Ionic Liquid as an Effective Additive for Rechargeable Magnesium Batteries
The effect of the addition of an ionic liquid DEME·TFSI to an electrolyte solution of Mg(HMDS)2-MgCl2 in THF was spectroscopically and electrochemically studied. Reversible magnesium deposition/dissolution and cycling of Mg-Mo6S8 coin cells were achieved with the DEME·TFSI-modified magnesium electrolyte. Read More
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Physical Organic Approach to Persistent, Cyclable, Low-Potential Electrolytes for Flow Battery Applications
A rare example of a high energy (low potential) anolyte with excellent stability in the charged state was identified. This material undergoes cycling at potentials lower than other studied materials but does not show degradation even after 200 charge-discharge cycles. Predictive multidimensional analysis, a technique common to physical organic chemistry, was successfully applied to the development of a model for RFB electrolytes that predicts their stability in the charged state with high accuracy. Read More
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Investigation of Mg Intercalation into α-V2O5 Using Atomic Resolution Transmission Electron Microscopy
We examine the effects of Mg intercalation into α-V2O5 using atomic-resolution scanning transmission electron microscopy (STEM) and electron energy-loss spectroscopy. The position of intercalated Mg within the V2O5 unit cell is directly identified using annular bright-field imaging, and found to be in agreement with prior density-functional theory models. Read More
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Feasibility of a Supporting Salt Free Non-aqueous Redox Flow Battery Utilizing Ionic Active Materials
We designed a non-aqueous flow battery that operates in the absence of supporting salt by utilizing redox active molecules that remain as ions across all accessible states of charge. Read More
Latest Updates
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You’re Invited - JCESR and Beyond: Translating the Basic Science of Batteries
Please join us at Argonne National Laboratory on Tuesday, April 4, 2023 for JCESR and Beyond: Translating the Basic Science of Batteries. Registration is now open. This in-person event will celebrate 10 years of research from the Joint Center… Read More
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A Message from JCESR: In Memory of George Crabtree
It is with heavy hearts that we say goodbye to George Crabtree, a Senior Scientist and Distinguished Fellow at Argonne National Laboratory, and Director of the Joint Center for Energy Storage Research (JCESR), who passed away unexpectedly on January 23. Dr. Read More
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Cyanopyridines As Extremely Low-Reduction-Potential Anolytes for Nonaqueous Redox Flow Batteries
Discovery of a cyanophenylpyridine derivative with a very low reduction potential and good stability during cycling. Read More
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Characterizing Redoxmer – Electrode Kinetics Using a SECM-Based Spot Analysis Method
Identified asymmetries in electron transfer (ET) kinetics between the reduction and oxidation of ferrocene-based redoxmers by measuring the ET rate constants (kf/kb) as a function of electrode potential. Read More
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Benzotriazoles as Low Potential Anolytes for Non-Aqueous Redox Flow Batteries
We developed an easy-to-synthesize benzotriazole-based anolyte with a high energy redox potential (-2.3 V vs Fc/Fc+) and high solubility that demonstrates stable electrochemical cycling performance. Read More