Imidazolium-based ionanofluid electrolytes with viscosity decoupled ion transport properties for lithium-ion batteries

A series of LiTFSI salt-doped ionanofluid electrolytes based on imidazolium ionic liquid that includes ionic liquid functionalized SnO2 nanoparticles were prepared through a simple solution-chemistry method. The obtained ionanofluid electrolytes exhibit high thermal stability, fragility, and substantially lower crystallinity than the original ionic liquid electrolytes. The temperature-dependent ion conductivity study indicates that in contrast to ionic liquid-based electrolytes, ionanofluid electrolytes are apparent to have viscosity-decoupled ion transport properties. The Li/LiFePO4 cell assembled with 15 wt% LiTFSI salt-doped ionanofluid electrolyte, having the highest Li+ ion transport ability with moderate ion conduc-tivity, demonstrates appreciable cycling performance with excellent rate capability. The cell delivers a room temperature discharge capacity of about similar to 141.2 mAhg(-1) (-88% of theoretical capacity (CTheo) of LiFePO4) at C/5 rate and is able to retain more than 96 % of the same with nearly 99 % coulombic efficiency after 50 charge-discharge cycles. The potentio-electrochemical impedance study reveal that the ionano-fluid electrolyte able to form a stable passivation layer within the cell. The study establishes the enor-mous potential of ionanofluid electrolytes for practical applications in next-generation lithium-ion batteries. (c) 2023 Elsevier B.V. All rights reserved.

Automated summary

A series of LiTFSI salt-doped ionanofluid electrolytes based on imidazolium ionic liquid were prepared, which included ionic liquid functionalized SnO2 nanoparticles. The obtained electrolytes exhibited high thermal stability, fragility, and lower crystallinity than the original ionic liquid electrolytes. The ionanofluid electrolytes displayed viscosity-decoupled ion transport properties and showed promising performance in lithium-ion batteries.