Now showing items 1-20 of 32

  • All-Dry Synthesis of Single Crystal NMC Cathode Materials for Li-Ion Batteries 

    Obrovac, MN; Zheng, Lituo; Craig Bennett, J. (The Electrochemical Society, 2020-10-08)
    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. ...
  • A Combinatorial Investigation of Fe-Si-Zn Thin Film Negative Electrodes for Li-ion 2 Batteries (Preprint) 

    Obrovac, MN; Brown, Z. L.; Smith, S (IOP Publishing, 2014-11-07)
    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 ...
  • Combinatorial Investigations of Ni-Si Negative Electrode Materials for Li-Ion Batteries 

    Obrovac, MN; Hatchard, T. D.; Du, Zhijia; Dunlap, RA (IOPscience, 2015-06-30)
    Sputtered thin films in the Ni-Si system (0 ≤ x ≤ 0.65 in NixSi1-x) were studied for use as anode materials in Li-ion cells. All compositions were found to be amorphous. The Ni in Ni-Si films was found to suppress the ...
  • Combinatorial Study of the Si-Sn-O System as Negative Electrode Materials in Li-Ion Cells 

    Obrovac, MN; Dunlap, RA; Zhao, Xiuyun; Schreiber, M. T.; MacEachern, Lauren; Sanderson, R. J. (The Electrochemical Society, 2015-11-17)
    SixSnyO1-x-y films with 0.45 < x < 0.80, 0.05 < y < 0.35, and 0.05 < (1-x-y) < 0.40 have been prepared using a magnetron sputtering method. All compositions had an amorphous structure and good capacity retention. Reversible ...
  • Electrochemical Activity of Nano-NiSi2 in Li Cells 

    Obrovac, MN; Du, Zhijia; Hatchard, T. D.; Bissonnette, Paul; Dunlap, R. A. (The Electrochemical Society, 2016-09-09)
    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 

    Obrovac, MN; Wilkes, B. N.; Brown, Z. L.; Krause, L. J.; Triemert, M. (The Electrochemical Society, 2015-12-09)
    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 

    Obrovac, MN; Dunlap, R. A.; Zheng, Lituo (The Electrochemical Society, 2016-04-08)
    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 

    Obrovac, MN; Cao, Yidan; Dunlap, R. A. (The Electrochemical Society, 2020-06-30)
    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 

    Obrovac, MN; Zhu, Min; Du, Zhijia; Liu, Hui (The Electrochemical Society, 2015-11-14)
    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 

    Obrovac, MN; Zhao, Xiuyun; Yao, Yuan; George, A. E.; Dunlap, R. A. (The Electrochemical Society, 2016-03-03)
    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 

    Obrovac, MN; Du, Zhijia; Liu, Hui; Ellis, S. N.; Dunlap, R. A.; Zhu, M. (The Electrochemical Society, 2016-04-20)
    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 

    Obrovac, MN; Zheng, Lituo; Garayt, M.D.L. (Elsevier Inc, 2020-04-14)
    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 ...
  • Honeycomb Compound Na3Ni2BiO6 as Positive Electrode Material in Na Cells 

    Obrovac, MN; Zheng, Lituo (The Electrochemical Society, 2016-08-31)
    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, ...
  • Inorganic Compounds as Binders for Si-Alloy Anodes 

    Wei, Congxiao; Obrovac, MN (The Electrochemical Society, 2021-02-01)
    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 

    Obrovac, MN; Cao, Yidan; Scott, Benjamin; Dunlap, R. A.; Wang, Jun (The Electrochemical Society, 2019-01-03)
    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 ...
  • Isothermal Calorimetry Evaluation of Metallurgical Silicon as a Negative Electrode Material for Li-Ion Batteries 

    Chevrier, V. L.; Yan, Zilai; Glazier, Stephen L.; Obrovac, MN; Krause, L. J. (The Electrochemical Society, 2021-03-01)
    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 ...
  • Li Insertion in Ball Milled Si-Mn Alloys 

    Obrovac, MN; Cao, Yidan; Craig Bennett, J; Dunlap, R. A. (The Electrochemical Society, 2018-06-08)
    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 ...
  • Li15Si4 Formation in Silicon Thin Film Negative Electrodes 

    Obrovac, MN; laboni, D.S.M (The Electrochemical Society, 2015-11-19)
    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 

    Obrovac, MN; Young, R. S.; Scott, B.; Wei, Congxiao (The Electrochemical Society, 2020-12-10)
    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 

    Obrovac, MN; Wang, Yukun; Cao, Simeng; Kalinina, Mariya; Zheng, Lituo; Li, Linjun; Zhu, Min (The Electrochemical Society, 2017-09-30)
    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. ...