Browsing Obrovac, Mark N. by Title
Now showing items 15-34 of 45
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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, ... -
Hydrothermally Deposited Carbon Coatings for Li-Ion Battery Active Materials Postprint
Hydrothermally deposited carbon coatings were evaluated for Li-ion battery materials. The applied coatings were found to be highly uniform and porous, with a density of 1.89 g/ml and a surface area of 370 m2/g. In lithium ... -
Implications of finite-size and surface effects on nanosize intercalation materials
A Monte Carlo simulation of a two-dimensional lattice gas with free boundaries is used to study the effects of surface and size on the chemical potential-composition curves of intercalation compounds. In particular we are ... -
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. ... -
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 ... -
Investigation of the NaNixMn1-xO2 (0 ≤ x ≤ 1) System for Na-ion Battery Cathode Materials (Preprint)
Layered NaNixMn1-xO2 (0 ≤ x ≤ 1) oxides were prepared via solid state reactions. Different reaction conditions were required to obtain phase pure samples, depending on the value of x. The 0 ≤ x ≤ 0.1 compositions were ... -
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 ... -
Lab-scale chemical vapor deposition onto powders
In this paper, a laboratory chemical vapor deposition (CVD) reactor is described, which features an opposing screw rotating fluidized bed. The reactor efficiently concentrates powdered reactants in the reaction zone while ... -
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 ... -
Li-ion Battery Negative Electrodes Based on the FexZn1-x Alloy System (Preprint)
Thin-film Fe-Zn libraries were investigated as negative electrode materials for Li-ion batteries using combinatorial and high-throughput techniques. X-ray diffraction, Mössbauer effect spectroscopy and electron microprobe ... -
Li15Si4 Formation in Silicon Thin Film Negative Electrodes
The conditions for Li15Si4 formation in Si thin film negative electrodes was studied during charge and discharge cycling in lithium cells. It was found that Li15Si4 formation can be suppressed during cycling of Si thin ... -
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 ... -
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. ... -
Mixed Transition Metal Titanate and Vanadate Negative Electrode Materials for Na-Ion Batteries (Preprint)
Sodium-ion batteries have the potential to be a low cost, sustainable replacement for lithium-ion batteries in large scale energy storage. The lack of practical negative electrode materials limit the development of Na-ion ... -
Mössbauer and Electrochemical Investigations of Carbon-Rich Fe1-xCx Films (Preprint)
A thin film binary library of carbon-rich Fe1-xCx (0.47 ≤ x ≤ 0.97) alloys was prepared by combinatorial sputtering of carbon and iron. The sputtered library was characterized by X-ray diffraction and room temperature 57Fe ... -
NixSi1-x Alloys Prepared by Mechanical Milling as Negative Electrode Materials for Lithium Ion Batteries
NixSi1-x (0 ≤ x ≤ 0.5, x = 0.05) alloys were prepared by ball milling and studied as anode materials for lithium ion batteries. Nanocrystalline Si/NiSi2 phases were formed for x ≤ 0.25. The NiSi phase was observed for ... -
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 ... -
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 ... -
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 ... -
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 ...