Browsing Obrovac, Mark N. by Title

Now showing items 22-41 of 45

  • Lab-scale chemical vapor deposition onto powders 

    113. Jun Wang and M.N Obrovac. Lab-scale Chemical Vapor Deposition onto Powders. AIP Advances, 12 (2022) 075209. doi: https://doi.org/10.1063/5.0095882
    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 

    Yidan Cao, J.C. Bennett, R.A. Dunlap and M.N. Obrovac, Li Insertion in Ball Milled Si-Mn Alloys, J. Electrochem. Soc., 165 (2018) A1734-A1740.
    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) 

    Published Version: L. MacEachern, R.A. Dunlap and M.N. Obrovac, Li-ion Battery Negative Electrodes Based on the FexZn1−x Alloy System, J. Non-Cryst. Solids, 409 (2015), 183-190. https://doi.org/10.1016/j.jnoncrysol.2014.11.026
    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 

    D.S. Iaboni and M.N. Obrovac, Li15Si4 Formation in Silicon Thin Film Negative Electrodes, J. Electrochem. Soc., 163 (2016), A255-A261.
    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 

    Robert S. Young, Benjamin Scott, Congxiao Wei and M. N. Obrovac. LiF as an Alloy Component or Slurry Additive in Si-Alloy Anodes. J. Electrochem. Soc. (2020), 167 (16), 160524.
    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 

    Yukun Wang, Simeng Cao, Mariya Kalinina, Lituo Zheng, Linjun Li, Min Zhu and M.N. Obrovac, Lithium Insertion in Nanostructured Si1-xTix Alloys, J. Electrochem. Soc., 164 (2017) A3006-A3010.
    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) 

    Published Version: L. Brown, S. Smith and M. N. Obrovac, Mixed Transition Metal Titanate and Vanadate Negative Electrode Materials for Na-Ion Batteries, J. Electrochem. Soc., 162 (2015), A15-A20. https://doi.org/10.1149/2.0171501jes
    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) 

    Published Version: Xiuyun Zhao, R.J. Sanderson, L. MacEachern, R.A. Dunlap and M.N. Obrovac, Mössbauer and Electrochemical Investigations of Carbon-Rich Fe1-xCxFilms, Electrochim. Acta, 170 (2015), 16-24. https://doi.org/10.1016/j.electacta.2015.04.116
    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 

    T.D. Hatchard, P. Bissonnette and M.N. Obrovac, Phenolic Resin as an Inexpensive High Performance Binder for Li-Ion Battery Alloy Negative Electrodes, J. Electrochem. Soc., 163 (2016) A2035-A2039.
    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 

    Michael Charlton, T. D. Hatchard, and M. N. Obrovac. Polyaniline Electrode Activation in Li Cells. J. Electrochem. Soc. (2020), 167 (8), 080501.
    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 

    Simeng Cao, Mohammad H. Tahmasebi, Shayne Gracious, J. Craig Bennett, and M. N. Obrovac. Preparation of Low Surface Area Si-Alloy Anodes for Li-Ion Cells by Ball Milling. J. Electrochem. Soc. (2022), 169 (6), 060540.
    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 

    Haonan Yu and M. N. Obrovac, Quantitative Determination of Carbon Dioxide Content in Organic Electrolytes by Infrared Spectroscopy, J. Electrochem. Soc., 166 (2019) A2467 - A2470
    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 ...

  • Quantitative Measurement of Compositional Inhomogeneity in NMC Cathodes by X-ray Diffraction Postprint 

    Published Version: Mohammad H. Tahmasebi and M.N.Obrovac. Quantitative Measurement of Compositional Inhomogeneity in NMC Cathodes by X-ray Diffraction. J.Electrochem. Soc. (2023). Accepted manuscript. https://doi.org/10.1149/1945-7111/acefff
    A novel X-ray diffraction (XRD) analysis technique is described for quantitatively measuring compositional inhomogeneity in Li[NixMnyCoz]O2 (NMC) cathode materials and NMC precursors. Single-phase rock salt precursors with ...

  • Rapid mechanochemical synthesis of amorphous alloys 

    T.D. Hatchard, A. Genkin and M.N. Obrovac, Rapid Mechanochemical Synthesis of Amorphous Alloys, AIP Advances, 7 (2017) 045201.
    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 ...

  • Reversible lithium insertion in catalytically graphitized sugar carbon 

    M.N. Obrovac, Xiuyun Zhao, L.T. Burke and R.A. Dunlap, Reversible Lithium Insertion in Catalytically Graphitized Sugar Carbon, Electrochem. Commun., 60 (2015), 221-224
    Highlights • First report of Li insertion in highly ordered catalytically derived graphite. • Fe catalyst combined with hard carbon precursors enable 1200 °C graphitization. • First report of highly ordered graphite ...

  • The Reversible Magnesiation of Pb (Preprint) 

    Published Version: Kalani Periyapperuma, Tuan T. Tran, M.I. Purcell and M.N. Obrovac, The Reversible Magnesiation of Pb, Electrochim. Acta, 165 (2015) 162-165. https://doi.org/10.1016/j.electacta.2015.03.006
    Sputtered Pb films have been found to reversibly alloy electrochemically with magnesium in Grignard based electrolytes. The voltage curve shows a single plateau at about 125 mV vs. Mg, corresponding to the formation of ...

  • Si85Fe15Ox Alloy Anode Materials with High Thermal Stability for Lithium Ion Batteries 

    Yijia Liu, Michael Charlton, Jun Wang, J. Craig Bennett and M. N. Obrovac. Si85 Fe15 Ox Alloy Anode Materials with High Thermal Stability for Lithium Ion Batteries. J. Electrochem. Soc. (2021), 168 (11), 110521.
    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) ...

  • Sintered polymeric binders for Li-ion battery alloy anodes 

    T.D. Hatchard, R.A. Fielden and M.N. Obrovac, Sintered Polymeric Binders for Li-ion Battery Alloy Anodes, Can. J. Chem., 96 (2018) 765-770.
    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 ...

  • Spherically Smooth Cathode Particles by Mechanofusion Processing 

    Lituo Zheng, Congxiao Wei, M. D. L. Garayt, Judy MacInnis, and M. N. Obrovac, Spherically Smooth Cathode Particles by Mechanofusion Processing, J. Electrochem. Soc., 166 (2019) A2924-A2927.
    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 ...