In situ real-time gravimetric and viscoelastic probing of surface films formation on lithium batteries electrodes

• DOI: 10.1038/s41467-017-01722-x
• Publication Date: 2017-11-03T16:35:08Z
• Authors: Vadim Dargel; Netanel Shpigel; Sergey Sigalov; Prasant Nayak; Mikhael D. Levi; Leonid Daikhin; Doron Aurbach
• Keywords: Science; Q; 01 natural sciences; Article; 0104 chemical sciences

AbstractIt is generally accepted that solid–electrolyte interphase formed on the surface of lithium-battery electrodes play a key role in controlling their cycling performance. Although a large variety of surface-sensitive spectroscopies and microscopies were used for their characterization, the focus was on surface species nature rather than on the mechanical properties of the surface films. Here we report a highly sensitive method of gravimetric and viscoelastic probing of the formation of surface films on composite Li4Ti5O12 electrode coupled with lithium ions intercalation into this electrode. Electrochemical quartz-crystal microbalance with dissipation monitoring measurements were performed with LiTFSI, LiPF6, and LiPF6 + 2% vinylene carbonate solutions from which structural parameters of the surface films were returned by fitting to a multilayer viscoelastic model. Only a few fast cycles are required to qualify surface films on Li4Ti5O12 anode improving in the sequence LiPF6 < LiPF6 + 2% vinylene carbonate << LiTFSI.