[8p-Z22-1~14] 1.4 Energy conversion, storage, resources and environment

△ [8p-Z22-10] Cycle Dependence of Activation Energy for Si/Graphite Sheet Composite Electrode

〇Jaeyoung Choi¹, Taketoshi Matsumoto¹ (1.ISIR, Osaka Univ.)

Keywords:Lithium ion batteries, Silicon anode, impedance

We have fabricated an Li ion battery electrode composed of composites of Si nanopowder from Si swarf and graphite sheets from expanded graphite. The solid electrolyte interphase resistance (Rsei) and the caharge transfer resistance (Rct) are calculated with Nyquist plots aqcuired by electrochemical impedance measurements at various temperatures. The activation energy calculated by Rsei and Rct changed from 0.404 eV to 0.464 eV and from 0.509 eV to 0.423 eV, respectively, in the range of the 6th and 300th cycles. These Rsei and Rct are less than those reported for graphite electrodes by other researchers.