The effects of BaTiO3 nanodots density support on epitaxial LiCoO2 thin-film for high-speed rechargeability

Sou Yasuhara, Shintaro Yasui, Takashi Teranishi, Yumi Yoshikawa, Tomoyasu Taniyama, Mitsuru Itoh

Research output: Contribution to journalArticle

Abstract

LiCoO2 (LCO) is one of the most promising cathode materials for Li ion batteries (LIBs). However, LCO shows a rate-limiting step of Li+ migration between electrode and electrolyte interfaces, requiring LIBs to be charged under low-current conditions. For next generation batteries, it will be necessary to meet the demand for a shorter charging-time. We investigated a support method for the LCO surface to improve high C-rate performance, and revealed that the Li+ intercalation/de-intercalation reaction into/from LCO was accelerated by the introduction of a BaTiO3-LCO-electrolyte interface (triple-phase interface; TPI), due to the electric field concentration near the TPI. In this report, we investigate the dependence of high C-rate performance on the density of surface BaTiO3 nanodots using epitaxial LiCoO2 thin films created via pulsed laser deposition (PLD). As the number of nanodots increased, so did discharge capacity at 50C, becoming saturated at surface coverage over 22%. However, at 100C, the discharge capacity decreased at surface coverage over 40%. These results indicate that coalescence of nanodots reduces not only the TPI length but also the electrochemically active range at quite high C-rate. Therefore, we infer that optimal surface coverage should be varied depending on the C-rate.

Original languageEnglish
Article number106604
JournalElectrochemistry Communications
Volume109
DOIs
Publication statusPublished - Dec 2019

Keywords

  • Density
  • Dielectrics
  • High speed chargeability
  • LiCoO
  • Nanodots

ASJC Scopus subject areas

  • Electrochemistry

Fingerprint Dive into the research topics of 'The effects of BaTiO<sub>3</sub> nanodots density support on epitaxial LiCoO<sub>2</sub> thin-film for high-speed rechargeability'. Together they form a unique fingerprint.

  • Cite this