Ionic Liquid Enabled FeS₂ for High‐Energy‐Density Lithium‐Ion Batteries

Abstract

High-energy-density FeS2 cathodes en-abled by a bis(trifluoromethanesulfonyl)imide (TFSI-) anion-based room temperature ionic liquid (RTIL) electrolyte are demonstrated. A TFSI-based ionic liquid (IL) significantly mitigates polysulfide dissolution, and therefore the parasitic redox shuttle mechanism, that plagues sulfur-based electrode chemistries. FeS2 stabilization with a TFSI(-) -based IL results in one of the highest energy density cathodes, 542 W h kg(-1) (normalized to cathode composite mass), reported to date.

Electrospun polyacrylonitrile microfiber separators for ionic liquid electrolytes in Li-ion batteries

“…6) [9]. The cycling stability observed in this experiment validates our claim that a nonwoven separator is an adequate replacement for conventional polyolefin materials in RTIL-based LIBs.…”

“…For example, TFSI À has been shown to mitigate sulfur dissolution and polysulfide redox shuttle in sulfur-based electrodes [9,10], FSI À shows strong compatibility with Li(Ni 1/3 Mn 1/3 Co 1/3 )O 2 cathodes [11] and graphite anodes [5,12], and both anions allow good reversibility of the Li metal electrode [13,14]. While much progress has been made in regards to developing high energy-density electrode-RTIL systems, research has overlooked one major hurdle for the commercialization of RTILs as LIB electrolytes: the separator material.…”

High Performance Non‐enzymatic Glucose Sensor Based on One‐Step Electrodeposited Nickel Sulfide

“…[15][16][17] Ar ange of TMCs such as molybdenum sulfide (MoS 2 ), tungsten sulfide (WS 2 ), nickel sulfide (NiS), iron sulfide (FeS 2 ), tin sulfide (SnS 2 )a nd copper sulfide (CuS) have been used for these applications. [18][19][20][21][22][23] Among the different TMCs, nickel sulfide (NiS) has received considerable interest for devices like supercapacitors or dyesensitized solar cells (DSSCs), because of its superior physicochemicalp roperties and good electrochemical performance. [24][25][26] Different stoichiometric phases of binary nickel sulfide compounds such as NiS, NiS 2 ,N i 2 S 2 and Ni 3 S 4 have been synthesized and characterized.…”

An Electrospun Core–Shell Nanofiber Web as a High‐Performance Cathode for Iron Disulfide‐Based Rechargeable Lithium Batteries

“…Moreover,w hen FeS 2 reacts with four Li + ions to produce Li 2 S, the polysulfide products generated tend to dissolve in the organic electrolyte and give rise to the redoxs huttle phenomenon, as in the case of lithium-sulfur batteries, resulting in severe capacity fading. [33][34][35][36] Although these approaches have significantly improved the reversibility and cycle performance of pyrite-based materials, highr ate-capability and long cycle life with adequate capacity retention still remain challenging. [13,16] Recent research and development efforts to enhancet he electrochemical properties of FeS 2 have been mainly focused on fabricating porous structures, [8,17] utilizingc onductive carbons such as graphene, [18][19][20][21][22] introducing transition metal dopants, [23][24][25] and employing carbon or polymer matrices for effective active materiale ncapsulation.…”