Lithium Ion Coupled Electron-Transfer Rates in Superconcentrated Electrolytes: Exploring the Bottlenecks for Fast Charge-Transfer Rates with LiMn2O4 Cathode Materials

Victoria A Nikitina; Maxim V Zakharkin; Sergey Yu Vassiliev; Lada V Yashina; Evgeny V Antipov; Keith J Stevenson

doi:10.1021/acs.langmuir.7b01016

Lithium Ion Coupled Electron-Transfer Rates in Superconcentrated Electrolytes: Exploring the Bottlenecks for Fast Charge-Transfer Rates with LiMn₂O₄ Cathode Materials

Langmuir. 2017 Sep 19;33(37):9378-9389. doi: 10.1021/acs.langmuir.7b01016. Epub 2017 Jul 3.

Authors

Victoria A Nikitina^{1

2}, Maxim V Zakharkin^{1

2}, Sergey Yu Vassiliev¹, Lada V Yashina¹, Evgeny V Antipov¹, Keith J Stevenson²

Affiliations

¹ M. V. Lomonosov Moscow State University , Leninskie Gory 1/3, Moscow 119991, Russia.
² Skolkovo Institute of Science and Technology , Moscow 143026, Russia.

PMID: 28636393
DOI: 10.1021/acs.langmuir.7b01016

Abstract

The charge-transfer kinetics of lithium ion intercalation into Li_xMn₂O₄ cathode materials was examined in dilute and concentrated aqueous and carbonate LiTFSI solutions using electrochemical methods. Distinctive trends in ion intercalation rates were observed between water-based and ethylene carbonate/diethyl carbonate solutions. The influence of the solution concentration on the rate of lithium ion transfer in aqueous media can be tentatively attributed to the process associated with Mn dissolution, whereas in carbonate solutions the rate is influenced by the formation of a concentration-dependent solid electrolyte interface (SEI). Some indications of SEI layer formation at electrode surfaces in carbonate solutions after cycling are detected by X-ray photoelectron spectroscopy. The general consequences related to the application of superconcentrated electrolytes for use in advanced energy storage cathodes are outlined and discussed.

Publication types

Research Support, Non-U.S. Gov't