Abstract
Solid electrolyte interface (SEI) is a critical factor that influences battery performance. SEI layer is formed by the decomposition of organic and inorganic compounds after the first cycle. This study investigates SEI formation as a product of electrolyte decomposition by the presence of flouro-o-phenylenedimaleimaide (F-MI) additive. The presence of fluorine on the maleimide-based additive can increase storage capacity and reversible discharge capacity due to high electronegativity and high electron-withdrawing group. The electrolyte containing 0.1 wt% of F-MI-based additive can trigger the formation of SEI, which could suppress the decomposition of remaining electrolyte. The reduction potential was 2.35 to 2.21 V vs Li/Li + as examined by cyclic voltammetry (CV). The mesocarbon microbeads (MCMB) cell with F-MI additive showed the lowest SEI resistance (Rsei) at 5898 Ω as evaluated by the electrochemical impedance spectroscopy (EIS). The morphology and element analysis on the negative electrode after the first charge-discharge cycle were examined by scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), and X-ray photoelectron spectroscopy (XPS). XPS result showed that MCMB cell with F-MI additive provides a higher intensity of organic compounds (RCH 2 OCO 2 Li) and thinner SEI than MCMB cell without an additive that provides a higher intensity of inorganic compound (Li 2 CO 3 and Li 2 O), which leads to the performance decay. It is concluded that attaching the fluorine functional group on the maleimide-based additive forms the ideal SEI formation for lithium-ion battery.
Original language | English |
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Pages (from-to) | 345-352 |
Number of pages | 8 |
Journal | Surface and Interface Analysis |
Volume | 51 |
Issue number | 3 |
DOIs | |
Publication status | Published - Mar 2019 |
Keywords
- F-MI additive
- SEI formation and mechanism
- lithium-ion battery