화학공학소재연구정보센터
Journal of Power Sources, Vol.247, 981-990, 2014
Analysis of solid electrolyte interface formation reaction and surface deposit of natural graphite negative electrode employing polyacrylic acid as a binder
We analyzed the solid electrolyte interface (SEI) formation reaction and surface deposit of a natural graphite (NG-3) electrode employing polyacrylic acid (PM) as a binder in an ethylene carbonate-based electrolyte because it was reported that the initial charge-discharge characteristics of the NG-3 electrode were improved by employing the PM binder. Poly(vinylidene fluoride) as a binder was used for comparison. We investigated the influence of the binder types on the coating of the NG-3 particles using the B.E.T. specific surface areas. The difference in the above phenomenon was explained by the relationship between the B.E.T. specific surface area and the irreversible capacity. The surface chemical composition of the NG-3 electrode was investigated by FE-SEM/EDX and XPS and then the difference between the PM binder and the PVdF binder was discussed. The FE-SEM/EDX and the XPS results showed that the amount of the inorganic components of the SEI was relatively small in the case of the PM binder NG-3 electrode. The AC impedance results showed that the SEI film resistance of the PM binder NG-3 electrode was lower at 0.2 V. It was clarified that the binder types affected the coating state, the SEI formation reaction, and the SEI film composition. (C) 2013 Elsevier B.V. All rights reserved.