High-power durability of LiCoO2 thin film electrode modified with amorphous lithium tungsten oxide

Tetsutaro Hayashi, Yasutaka Matsuda, Naoaki Kuwata, Junichi Kawamura

    Research output: Contribution to journalArticle

    5 Citations (Scopus)

    Abstract

    To investigate electrochemical performances of an amorphous lithium tungsten oxide (LWO) layer, an amorphous LWO-modified LiCoO2 (LCO) thin film electrode is fabricated by pulsed laser deposition and is exposed under a humid environment. The amorphous LWO-modified LCO exhibits high capacity retention of 80% at a rapid charge-discharge rate of 20 C. Conversely, the bare LCO exhibits capacity retention of 0% at the rates of 20 C. Electrochemical impedance spectroscopy demonstrates that the LWO-modified LCO maintains a low interfacial resistance after the cycling test compared with the bare LCO. X-ray photoemission spectroscopy (XPS), scanning transmission microscopy (STEM), and electron energy loss spectroscopy (EELS) indicate the presence of Li2CO3 on the surface of the bare LCO electrode and a thick degraded surface layer of CoO structure on the surface of LCO primary particle after electrochemical tests. XPS, STEM, and EELS indicate the presence of low amounts of Li2CO3 on the surface of the LWO-modified LCO, the LCO layer remains in a normal state, and LWO layer maintains the amorphous LWO state after the tests. Thus, the amorphous LWO protective layer contributes to suppressing the degradation of LCO and maintaining an amorphous LWO state with a lithium ion conductor, resulting in high-power durability.

    Original languageEnglish
    Pages (from-to)41-47
    Number of pages7
    JournalJournal of Power Sources
    Volume354
    DOIs
    Publication statusPublished - 2017 Jan 1

    Keywords

    • Amorphous lithium tungsten oxide
    • High-power
    • Lithium cobalt oxide
    • Lithium ion battery
    • Pulsed laser deposition

    ASJC Scopus subject areas

    • Renewable Energy, Sustainability and the Environment
    • Energy Engineering and Power Technology
    • Physical and Theoretical Chemistry
    • Electrical and Electronic Engineering

    Fingerprint Dive into the research topics of 'High-power durability of LiCoO<sub>2</sub> thin film electrode modified with amorphous lithium tungsten oxide'. Together they form a unique fingerprint.

  • Cite this