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

Abstract

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 v/v). The effect of electrolyte type on the electrochemical performance of a LiCoO2 cathode and a SnO2/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−1 to ~26 mS·cm−1 at room temperature. Additionally, at a temperature of 100 °C, an increase in ionic conductivity from ~38 to ~69 mS·cm−1 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 LiCoO2 cathode with the MOILE (without SN) exhibited a 39% specific capacity loss at the 50th cycle while the LiCoO2 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 SnO2/C composite-fiber anode resulted in improved cycling performance and rate capability of the SnO2/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.

Centrifugally spun carbon fibers prepared from aqueous poly(vinylpyrrolidone) solutions as binder‐free anodes in lithium‐ion batteries

“…Therefore, researchers and industry have turned their attention to less hazardous and more environmentally benign alternatives, such as PVP and PVA precursor fibers. Both PVP and PVA, in contrast to PAN, are water‐soluble and have been recently used in energy storage applications, 11,15,16,1718,19 . PVP, particularly, is considered a potential carbon precursor alternative to produce CF anodes due to its low cost.…”

Composite Electrolyte & Electrode Membranes for Electrochemical Energy Storage & Conversion Devices

“…The effect of ionic liquid addition into GPEs is reported and discussed also in the contribution by Villarreal et al [ 4 ], who have been investigating a mixed organic/ionic liquid electrolytic system. In addition, the authors studied the beneficial effect of incorporation of succinonitrile additive (5 wt.%) on the GPE ion transport properties and on the cycling performance of Li/SnO 2 -C and Li/LiCoO 2 polymer half-cells.…”

Paddle-wheel mechanism in doped succinonitrile–glutaronitrile plastic electrolyte: a joint magnetic resonance, dielectric, and viscosimetry study of Li ion translational and molecular reorientational dynamics

“…Whether used as simple plasticizers among more complex systems or as main matrices, dinitriles such as NRC-(CH 2 ) n -CRN are subject to extensive research and have proven to be suitable electrolytes for Li ion batteries when doped with sufficient amounts of Li salt. [1][2][3][4][5][6][7][8][9][10][11] Their relatively high ionic conductivity, even in the absence of a dopant, 12 alongside with their low toxicity and low flammability, make them particularly compelling candidates for battery research.…”