NMR quantitative analysis of solid electrolyte interphase on aged Li-ion battery electrodes

作者：Castaing Remi; Moreau Philippe; Reynier Yvan; Schleich Donald; Larbi Severine Jouanneau Si; Guyomard Dominique; Dupre Nicolas^*

来源：Electrochimica Acta, 2015, 155: 391-395.

DOI：10.1016/j.electacta.2014.12.049

• Li-ion battery
• surface
• NMR
• LiF
• parasitic reactions

The surface chemistry of aged Li4Ti5O12 and LiFePO4 electrodes that have been cycled in a full cell configuration are examined using nuclear magnetic resonance. The failure mechanism of such cells has been previously identified to be an electrode capacity slippage process caused by the loss of charge carriers: electrons or lithium ions. The electrode-electrolyte interphase is quantitatively analyzed after cycling thanks to a calibration of NMR spectra. LiF is detected at both electrodes: about 1.2 mu mol mg(-1) at the Li4Ti5O12-based electrode and about 0.35 mu mol mg(-1) at the LiFePO4-based electrode, and it is the main component amongst lithiated species. By comparison with gravimetric studies, LiF cannot be the only component of the interphase. From a correlation between the amount of detected LiF and the electrode capacity slippage of the battery, different reaction paths are proposed at each electrode, involving either moisture-driven catalysis or reductive process that consumes a quantity of charge from the electrode.

• 出版日期2015-2-10
• 单位中国地震局