Chemistry Faculty Research, Publications and Presentations: Recent submissions
Now showing items 21-40 of 235
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Electrochemistry and Thermal Behavior of SiOx Made by Reactive Gas Milling
SiOx with various oxygen contents were synthesized from Si powder by a simple room-temperature ball milling method by controlling the air exposure time during milling. The resulting SiOx consists of nano and amorphous Si ... -
Engineered Particle Synthesis by Dry Particle Microgranulation
Highlights * A method of making monodisperse engineered ∼10-μm particles is introduced * Core-shell, spherical, and tetrahedral particles demonstrated at ∼100% yield * Spherical layered oxides for Li-ion batteries ... -
Polyaniline Electrode Activation in Li Cells
Polyaniline (PANi) can be used as an electroactive organic cathode material in Li-cells with multiple redox states. The theoretical specific capacity of the emeraldine base (PEB) is 150 mAh g−1. In this study, we show how ... -
Spherically Smooth Cathode Particles by Mechanofusion Processing
Surface modification has been shown to be useful for improving the cycling performance of cathode materials. Typically hetero-compositional coatings are applied on cathode particle surfaces using methods, such as aqueous ... -
Quantitative Determination of Carbon Dioxide Content in Organic Electrolytes by Infrared Spectroscopy
CO2 has been shown to be an effective additive to improve the cycling characteristics of silicon negative electrodes for Li-ion batteries. However, a quantitative technique for measuring the CO2 content in electrolyte is ... -
Stabilizing NaCrO2 by Sodium Site Doping with Calcium
Layered cathode materials based on abundant, low cost raw materials have garnered interest in recent years. O3-type NaCrO2 is a promising cathode material as it offers decent energy density and is easy to synthesize. In ... -
An Investigation of the Fe-Mn-Si System for Li-Ion Battery Negative Electrodes
Fe-Mn-Si alloys prepared by ball milling were investigated as negative electrodes for Li-ion batteries. X-ray diffraction and room temperature 57Fe Mössbauer measurements were used to characterize alloy structure, which ... -
Li Insertion in Ball Milled Si-Mn Alloys
Si1-xMnx (0 ≤ x ≤0.5, x=0.05)alloyswereprepared by ball milling and studied as negative electrode materials in Li cells. These alloys were found to be unique amongtransition metals. When x ≤ 0.35, the alloys are essentially ... -
Sintered polymeric binders for Li-ion battery alloy anodes
The cycling performance in lithium half cells of Si alloy electrodes with polyvinylidene fluoride or polyimide binders were evaluated after the electrodes were cured at temperatures below and above the binder carbonization ... -
Preparation of Low Surface Area Si-Alloy Anodes for Li-Ion Cells by Ball Milling
A new and simple 2-step milling technique is utilized to produce Si–Ti–N alloys with significantly reduced surface area compared to conventional ball milling, while still attaining a full amorphous active Si phase. Surface ... -
Si85Fe15Ox Alloy Anode Materials with High Thermal Stability for Lithium Ion Batteries
The synthesis, microstructure and electrochemical properties of ball milled Si85Fe15Ox alloys with different oxygen contents are investigated. These materials combine the features of Si-M alloys (low irreversible capacity) ... -
Isothermal Calorimetry Evaluation of Metallurgical Silicon as a Negative Electrode Material for Li-Ion Batteries
The structural evolution of Si during lithiation and delithiation is uniquely dependent on the cycling conditions and can show either reversible or path dependent behavior. In this paper, metallurgical Si (large crystalline ... -
Inorganic Compounds as Binders for Si-Alloy Anodes
The inorganic compounds, lithium polysilicate (Li2Si5O11), sodium polyphosphate ((NaPO3)n), and lithium phosphate monobasic (H2LiPO4) were investigated as the sole binders in Si-alloy and graphite electrodes for Li cells. ... -
LiF as an Alloy Component or Slurry Additive in Si-Alloy Anodes
Electrolyte additives are commonly used to improve electrochemical performance in Li-ion cells. The use of solids as electrolyte additives is far less common. Here, Si40'(FeSi2)(60−x)'(LiF)(x)' (' = volume percent) alloys ... -
All-Dry Synthesis of Single Crystal NMC Cathode Materials for Li-Ion Batteries
Single crystal (SC) cathode materials with a layered structure are considered to be state-of-the-art for lithium ion batteries. However, their production involves many steps and can produce large amounts of wastewater. ... -
Lithium Insertion in Nanostructured Si1-xTix Alloys
Nanostructured Si1-xTix alloys (0 ≤ x ≤ 0.3) prepared by ball milling were studied as negative electrode materials in Li cells. The alloys comprised a nanocrystalline andamorphousSiphaseandananocrystallineC49TiSi2 phase. ... -
Rapid mechanochemical synthesis of amorphous alloys
A rapid method for preparing amorphous alloys has been developed utilizing a SPEX high energy ball mill. Parameters such as ball size, mass of balls and milling time, were systematically optimized to prepare amorphous ... -
Electrochemical Activity of Nano-NiSi2 in Li Cells
Crystalline and nanocrystalline NiSi2 were studied as negative electrode materials in Li cells. Crystalline NiSi2 was found to be inactive toward lithiation/delithiation. However, it was found that NiSi2 becomes active ... -
Honeycomb Compound Na3Ni2BiO6 as Positive Electrode Material in Na Cells
Honeycomb compound Na3Ni2BiO6 was synthesized and studied as positive electrode material in sodium cells for the first time. This material exhibits a reversible capacity of ∼80 mAh/g and an average voltage of ∼3.1 V, ... -
Phenolic Resin as an Inexpensive High Performance Binder for Li-Ion Battery Alloy Negative Electrodes
Phenolic resin was evaluated as a binder material for Li-ion battery negative electrodes containing Si-based alloys. Phenolic resin was found to have a large first lithiation capacity of about 1200 mAh/g, which is suspected ...