Scholarly Publications - Chemistry

Permanent URI for this collectionhttps://hdl.handle.net/11693/115489

Browse

Browsing Scholarly Publications - Chemistry by Author "Abruna, H. D."

Filter results by typing the first few letters
Now showing 1 - 2 of 2
  • Thumbnail Image
    ItemOpen Access
    Electrolyte screening studies for Li metal batteries
    (Royal Society of Chemistry, 2020-08) Seok, J.; Zhang, N.; Ulgut, Burak; Jin, A.; Yu, S.-H.; Abruna, H. D.
    From 60 solvent electrolyte combinations tested, we find that Li metal anodes, tested in 1 M LiFSI in DOL:DME exhibit an outstanding cycling performance (>500 cycles) even at high current densities (3 mA cm−2). The excellent performance is ascribed, at least in part, to a low Li nucleation overpotential and a low charge transfer resistance during cycling.
  • Thumbnail Image
    ItemOpen Access
    Phenothiazine-based polymer cathode materials with ultrahigh power densities for lithium ion batteries
    (American Chemical Society, 2018) Peterson, B. M.; Ren, D.; Shen, L.; Wu, Y. -C. M.; Ülgüt, Burak; Coates, G. W.; Abruna, H. D.; Fors, B. P.
    Lithium ion batteries (LIBs) currently deliver the highest energy density of any known secondary electrochemical energy storage system. However, new cathode materials, which can deliver both high energy and power densities, are needed to improve LIBs. Herein, we report on the synthesis of a new organic-based redox-active material centered about phenothiazine and phenylenediamine units. Improved Coulombic efficiencies and greater capacity retention during cycling are observed through the copolymerization of a phenothiazine-based monomer that yields cross-linked materials. With this as the positive electrode in Li-coin cells, high specific capacities (150 mAh/g) are delivered at very positive operating voltages (2.8−4.3 V vs Li+ /Li), yielding high energy densities. The material has low charge transfer resistance as verified by electrochemical impedance spectroscopy, which contributes in delivering previously unseen power densities in coin cells for organic-based cathodes. Excellent retention of capacity (82%) is observed at ultrafast discharge rates (120 C).