Browsing Obrovac, Mark N. by Title

Now showing items 6-25 of 45

  • Electrochemical Activity of Nano-NiSi2 in Li Cells 

    Zhijia Du, T.D. Hatchard, P. Bissonnette, R. A. Dunlap and M. N. Obrovac, Electrochemical Activity of Nano-NiSi2 in Li Cells, J. Electrochem. Soc., 163 (2016) A2456-A2460.
    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 ...

  • The Electrochemical Behavior of Polyimide Binders in Li and Na Cells 

    B. N. Wilkes, Z. L. Brown, L. J. Krause, M. Triemert and M. N. Obrovac, The Electrochemical Behavior of Polyimide Binders in Li and Na Cells, J. Electrochem. Soc., 163 (2016), A364-A372.
    The electrochemistry of aromatic and aliphatic polyimide binders was characterized in composite coatings for Li-ion and Na-ion battery negative electrodes. Aromatic polyimide was found to have a large first lithiation ...

  • The Electrochemical Reaction Mechanism of Tin Phosphide with Sodium 

    Lituo Zheng, R.A. Dunlap and M.N. Obrovac, The Electrochemical Reaction Mechanism of Tin Phosphide with Sodium, J. Electrochem. Soc., 163 (2016), A1188-1191.
    The sodiation mechanism of Sn4P3 was studied by ex-situ X-ray diffraction and Mössbauer effect spectroscopy. These results show that Sn4P3 is initially amorphized during sodiation, and suggest that upon further sodiation ...

  • Electrochemistry and Thermal Behavior of SiOx Made by Reactive Gas Milling 

    Yidan Cao, R. Dunlap, and M. N. Obrovac. Electrochemistry and Thermal Behavior of SiOx Made by Reactive Gas Milling. J. Electrochem. Soc. (2020), 167 (11), 110501.
    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 ...

  • The Electrochemistry of Amorphous Si-B Thin Film Electrodes in Li Cells 

    Hui Liu, Min Zhu, Zhijia Du and M.N. Obrovac, The Electrochemistry of Amorphous Si-B Thin Film Electrodes in Li Cells, J. Electrochem. Soc., 163 (2016), A192-A196
    Abstract Si1-xBx thin films of 0.071 ≤ x ≤ 0.950 have been synthesized using combinational sputtering. All Si1-xBx film compositions had a highly amorphous structure consisting of amorphous Si and B phases, as characterized ...

  • Electrochemistry of Catalytically Graphitized Ball Milled Carbon in Li Batteries 

    High carbon Fe-C composites with starting concentrations of 10, 20, 30, and 40 wt% Fe (2.3 - 12.5 atomic % Fe) were prepared by ball milling followed by annealing. Increasing the Fe concentration and annealing temperature ...

  • Electrochemistry of CuxSi1−x Alloys in Li Cells 

    Zhijia Du, Hui Liu, S.N. Ellis, R.A. Dunlap, M. Zhu and M.N. Obrovac, Electrochemistry of CuxSi1−x Alloys in Li Cells, J. Electrochem. Soc., 163 (2016), A1275-1279.
    The structure and electrochemistry in lithium cells of sputtered thin films and ball milled alloys in the Cu-Si system (0 ≤ x ≤ 0.60 in CuxSi1−x) were investigated. Both thin films and ball milled Cu-Si alloys showed the ...

  • Engineered Particle Synthesis by Dry Particle Microgranulation 

    Lituo Zheng, M. D. L. Garayt, and M. N. Obrovac, Engineered Particle Synthesis by Dry Particle Microgranulation. Cell Reports Physical Science (2020), 1 (6), 100063.
    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 ...

  • Explanation for the 4.8-V plateau LiCrxMn2-xO4 

    Obrovac, MN, Y. Gao, and JR Dahn. 1998. "Explanation for the 4.8-V plateau LiCrxMn2-xO4." Physical Review B 57(10): 5728-5733.
    Using the results of photoelectron spectroscopy (PES) measurements on LiCrxMn2-xO4 we provide an explanation for the origin of the 4.8-V plateau in Li/LiCrxMn2-xO4 cells. PES shows that the d bands derived from Mn 3d e(g) ...

  • Honeycomb Compound Na3Ni2BiO6 as Positive Electrode Material in Na Cells 

    Lituo Zheng and M.N. Obrovac, Honeycomb Compound Na3Ni2BiO6 as Positive Electrode Material in Na Cells, J. Electrochem. Soc., 163 (2016) A2362-A2367.
    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 

    Published Version: Jun Wang, Yidan Cao and M.N Obrovac. Hydrothermally Deposited Carbon Coatings for Li-Ion Battery Active Materials. J.Electrochem. Soc. (2023). Accepted manuscript. https://doi.org/10.1149/1945-7111/acf0
    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 

    Obrovac, MN, and JR Dahn. 2000. "Implications of finite-size and surface effects on nanosize intercalation materials." Physical Review B 61(10): 6713-6719.
    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 

    Congxiao Wei and M. N. Obrovac. Inorganic Compounds as Binders for Si-Alloy Anodes. J. Electrochem. Soc. (2021), 168(2), 020505.
    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 

    Yidan Cao, Benjamin Scott, R.A. Dunlap, Jun Wang and M.N. Obrovac, An Investigation of the Fe-Mn-Si System for Li-Ion Battery Negative Electrodes, J. Electrochem. Soc., 166 (2019) A21-A26. doi: 10.1149/2.1111816jes
    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) 

    Published Version: R. Fielden and M. N. Obrovac, Investigation of the NaNixMn1-xO2 (0 ≤ x ≤ 1) System for Na-Ion Battery Cathode Materials, J. Electrochem. Soc., 162 (2015), A453-A459. https://doi.org/10.1149/2.0551503jes
    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 

    Chevrier, Zilai Yan, Stephen L. Glazier, M. N. Obrovac and L.J. Krause. Isothermal Calorimetry Evaluation of Metallurgical Silicon as a Negative Electrode Material for Li-Ion Batteries. J. Electrochem. Soc. (2021), 168 (3), 030504.
    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 

    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 ...