A5054738892- Advancements in Battery Materials
- Advanced Battery Materials and Technologies
- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Advanced Battery Technologies Research
- Supercapacitor Materials and Fabrication
- Ionic liquids properties and applications
- Advanced battery technologies research
- Extraction and Separation Processes
- Semiconductor materials and interfaces
- Solid-state spectroscopy and crystallography
- Fuel Cells and Related Materials
- Semiconductor materials and devices
- Chemical and Physical Properties in Aqueous Solutions
- Layered Double Hydroxides Synthesis and Applications
- Membrane-based Ion Separation Techniques
- Inorganic Fluorides and Related Compounds
- Crystallography and molecular interactions
- Graphene research and applications
- Thermodynamic properties of mixtures
- Thermal Expansion and Ionic Conductivity
- Force Microscopy Techniques and Applications
- Anodic Oxide Films and Nanostructures
- Transition Metal Oxide Nanomaterials
- Surface and Thin Film Phenomena
National Renewable Energy Laboratory
2018-2024
Sejong University
2023-2024
North Carolina State University
2011-2022
Argonne National Laboratory
2015-2020
Alex's Lemonade Stand Foundation
2015-2016
Gwangju Institute of Science and Technology
2008-2015
A beyond Li-ion battery based on Zn metal, aprotic electrolyte, and a hydrated bilayered V2O5 cathode with large gallery spacing of 11–13 Å is introduced. The exhibits high 20 C rate capability good specific capacity 130 mA h g−1. This work provides some design rules for intercalation behavior in host electrodes nonaqueous environment. As service to our authors readers, this journal supporting information supplied by the authors. Such materials are peer reviewed may be re-organized online...
The electrolyte solution structure for acetonitrile (AN)-lithium salt mixtures has been examined highly dissociated salts. Phase diagrams are reported (AN)n-LiN(SO2CF3)2 (LiTFSI) and -LiPF6 electrolytes. Single crystal structures Raman spectroscopy have utilized to provide information regarding the solvate species present in solid-state liquid phases, as well average solvation number variation with concentration. Molecular dynamics (MD) simulations of correlated experimental data additional...
Unlike the more established lithium-ion based energy storage chemistries, complex intercalation chemistry of multivalent cations in a host lattice is not well understood, especially relationship between intercalating species solution and prevalence type side reactions. Among metals, promising model system can be on nonaqueous Zn2+ ion chemistry. Several examples these systems support use Zn metal anode, reversible cathodes have been reported. This study utilizes combination analytical tools...
Through coupled experimental analysis and computational techniques, we uncover the origin of anodic stability for a range nonaqueous zinc electrolytes. By examination electrochemical, structural, transport properties electrolytes with varying concentrations, it is demonstrated that acetonitrile–Zn(TFSI)2, acetonitrile–Zn(CF3SO3)2, propylene carbonate–Zn(TFSI)2 can not only support highly reversible Zn deposition behavior on metal anode (≥99% Coulombic efficiency) but also provide high (up to...
Direct evidence of Mg2+ intercalation into a spinel-type Mn2O4 is provided. By combining tools with different sensitivities, from atomic-resolution X-ray spectroscopy to bulk diffraction, it demonstrated that reversibly occupies the tetrahedral sites spinel structure through reduction Mn when electrochemical reaction performed. As service our authors and readers, this journal provides supporting information supplied by authors. Such materials are peer reviewed may be re-organized for...
The lithium-sulfur battery has long been seen as a potential next generation chemistry for electric vehicles owing to the high theoretical specific energy and low cost of sulfur. However, even state-of-the-art batteries suffer from short lifetimes due migration highly soluble polysulfide intermediates exhibit less than desired density required excess electrolyte. use sparingly solvating electrolytes in is promising approach decouple electrolyte quantity reaction mechanism, thus creating...
Silicon (Si) is the most naturally abundant element possessing 10-fold greater theoretical capacity compared to that of graphite-based anodes. The practicality implementing Si anodes is, however, limited by unstable solid/electrolyte interphase (SEI) and anode fracturing during continuous lithiation/delithiation. We demonstrate glyme-based electrolytes (GlyEls) ensure a conformal SEI on keep "fracture-free". Benchmarking against optimal, commonly used carbonate electrolyte with...
Solution structure is the key determinant for electrolyte properties, but little known about ion solvate structures present in liquids. A detailed exploration of this topic begun here utilizing acetonitrile (AN) due to simplicity solvent's interactions with Li+ cations. Phase diagrams have been prepared (AN)n-LiClO4 and -LiBF4 mixtures (salts intermediate ionic association). The species solid liquid phases analyzed single crystal Raman spectroscopy determine how anion identity influences...
A systematic study of electrolytes has been conducted to explore how solution structure dictates electrolyte properties. Specifically, the transport properties (viscosity, conductivity and molar conductivity) acetonitrile-lithium salt mixtures, (AN)n-LiX, are reported for with LiPF6, LiTFSI (i.e., LiN(SO2CF3)2), LiClO4, LiBF4 LiCF3CO2. These salts have widely varying ion solvation/ionic association behavior which is directly reflected in AN solutions. Information about utilized, concert...
Electrolytes with the salt lithium bis(fluorosulfonyl)imide (LiFSI) have been evaluated relative to comparable electrolytes other salts. Acetonitrile (AN) has used as a model electrolyte solvent due simplicity of its solvation interactions (the AN molecule only single electron lone-pair for Li+ cation coordination). The information obtained from thermal phase behavior, solvation/ionic association interactions, quantum chemical (QC) calculations and molecular dynamics (MD) simulations (with...
Raman spectroscopy is a powerful method for identifying ion–ion interactions, but only if the vibrational band signatures anion coordination modes can be accurately deciphered. The present study characterizes PF6– P–F symmetric stretching evaluating PF6–···Li+ cation interactions within LiPF6 crystalline solvates to create characterization tool liquid electrolytes. To facilitate this, crystal structures two new solvates—(G3)1:LiPF6 and (DEC)2:LiPF6 with triglyme diethyl carbonate,...
Hybrid supercapacitors that follow a "rocking-chair"-type mechanism were developed by coupling divalent metal and activated carbon electrodes in nonaqueous electrolytes. Conventional require large amount of electrolyte to provide sufficient quantity ions the electrodes, due their Daniell-type depletes from while charging. The alternative effectively enhances energy density minimizing necessary electrolyte, because ion is replenished anode it adsorbed cathode. Newly electrolytes for Mg Zn...
While α-V2O5 has traditionally been considered as a promising oxide to reversibly intercalate high levels of Mg2+ at potential, recent reports indicate that previously observed electrochemical activity is dominated by intercalation H+ rather than Mg2+, even in moderately dry nonaqueous electrolytes. Consequently, the inherent functionality oxides remains question. By conducting electrochemistry chemically and anodically stable ionic liquid electrolyte, we report that, 110 °C, layered indeed...
A 74 wt% silicon composite electrode delivers 1000 cycles with 74% capacity retention against NMC811 cathodes and a cell stack energy density of 212 W h kg −1 in standard carbonate electrolyte two simple chemical process improvements.
The energy density of rechargeable batteries utilizing metals as anodes surpasses that Li ion batteries, which employ carbon instead. Among possible metals, magnesium represents a potential alternative to the conventional choice, lithium, in terms storage density, safety, stability, and cost. However, major obstacle for metal-based is identification electrolytes show reversible deposition/dissolution metal anode support intercalation ions into cathode. Traditional Grignard-based Mg are...
Lithium difluoro(oxalato)borate (LiDFOB) is a relatively new salt designed for battery electrolyte usage. Limited information currently available, however, regarding the ionic interactions of this (i.e., solvate formation) when it dissolved in aprotic solvents. Vibrational spectroscopy particularly useful tool identifying these interactions, but only if vibrational bands can be correctly linked to specific forms anion coordination. Single crystal structures LiDFOB solvates have therefore...
The development of a Mg ion based energy storage system could provide several benefits relative to today's Li-ion batteries, such as improved density. electrolytes for which are typically designed efficiently plate and strip Mg, have not yet been proven work with high voltage cathode materials that needed achieve One possibility is these inherently unstable on porous electrodes. To determine if this indeed the case, electrochemical properties variety were tested using carbon coating graphite...
Silicon is a promising alloying anode for lithium-ion batteries because of its high capacity and low cost. However, use has been hampered by mechanical failure arising from the large volume change upon cycling an insufficiently stable solid electrolyte interphase (SEI). SEI formation depends on Si surface, which often oxide (SiOx). In this study we compare three different surfaces using wafers: 1.3 nm native SiOx, 1.4 thermally grown SiO2, SiOx-free surface. The oxide-free surface showed...
Lithium transition-metal oxides (LiMn2O4 and LiMO2 where M = Ni, Mn, Co, etc.) are widely applied as cathode materials in lithium-ion batteries due to their considerable capacity energy density. However, multiple processes occurring at the cathode/electrolyte interface lead overall performance degradation. One key failure mechanism is dissolution of transition metals from cathode. This work presents results combining scanning electrochemical microscopy with inductively coupled plasma (ICP)...
Development of a strong Lewis acid-free and phenolate-based electrolyte for rechargeable magnesium-ion batteries.
Two Mg–Li dual salt hybrid electrolytes are developed, which exhibit excellent oxidative stability up to around 3.8 V (<italic>vs.</italic> Mg/Mg<sup>2+</sup>) on Al, and were successfully applied in cells with lithium-ion intercalation cathodes magnesium metal anodes.
Renewable biomaterials are catalytically converted to graphite for use in lithium-ion anodes using a simple and scalable process.