The Use of Succinonitrile as an Electrolyte Additive for Composite-Fiber Membranes in Lithium-Ion Batteries

• Published in: Membranes (Basel) 2020-03, Vol.10 (3), p.45
• Main Authors: Villarreal, Jahaziel, Orrostieta Chavez, Roberto, Chopade, Sujay A, Lodge, Timothy P, Alcoutlabi, Mataz
• Format: Article
• Language: English
• Subjects: Additives; Anodes; Cathodes; Chromatography; composite fibers; Conductivity; Discharge; Electrochemical analysis; Electrochemistry; electrolyte; Electrolytes; Electrolytic cells; Investigations; Ion currents; Ionic liquids; Lithium; Lithium compounds; Lithium-ion batteries; Membranes; mixtures; Organic solvents; Polarity; Rechargeable batteries; Room temperature; Salts; Specific capacity; Succinonitrile; Temperature effects; Tin dioxide
• ISSN: 2077-0375; 2077-0375
• DOI: 10.3390/membranes10030045

In the present work, the effect of temperature and additives on the ionic conductivity of mixed organic/ionic liquid electrolytes (MOILEs) was investigated by conducting galvanostatic charge/discharge and ionic conductivity experiments. The mixed electrolyte is based on the ionic liquid (IL) (EMI/TFSI/LiTFSI) and organic solvents EC/DMC (1:1 / ). The effect of electrolyte type on the electrochemical performance of a LiCoO cathode and a SnO /C composite anode in lithium anode (or cathode) half-cells was also investigated. The results demonstrated that the addition of 5 wt.% succinonitrile (SN) resulted in enhanced ionic conductivity of a 60% EMI-TFSI 40% EC/DMC MOILE from ~14 mS·cm to ~26 mS·cm at room temperature. Additionally, at a temperature of 100 °C, an increase in ionic conductivity from ~38 to ~69 mS·cm was observed for the MOILE with 5 wt% SN. The improvement in the ionic conductivity is attributed to the high polarity of SN and its ability to dissolve various types of salts such as LiTFSI. The galvanostatic charge/discharge results showed that the LiCoO cathode with the MOILE (without SN) exhibited a 39% specific capacity loss at the 50th cycle while the LiCoO cathode in the MOILE with 5 wt.% SN showed a decrease in specific capacity of only 14%. The addition of 5 wt.% SN to the MOILE with a SnO /C composite-fiber anode resulted in improved cycling performance and rate capability of the SnO /C composite-membrane anode in lithium anode half-cells. Based on the results reported in this work, a new avenue and promising outcome for the future use of MOILEs with SN in lithium-ion batteries (LIBs) can be opened.