Solid state polymer ionogel electrolyte for use in Li‐ion batteries

Abstract

This work presents a preparation method for solid state ionogel electrolyte membranes intended for lithium-ion batteries (LIBs). These membranes are obtained by filling the pores of syndiotactic polystyrene (sPS) gels with an ionic liquid (IL) that is later polymerized. The aim is to improve the thermal stability and mechanical properties in conjunction with mitigation of ionic liquid loss from ionogel electrolyte membranes at high application temperatures (>50 C). Such ionogel membranes circumvent the dimensional stability issues of polyolefin membranes at >90 C, volatility and flammability issues of organic liquid electrolytes, and ionic liquid loss due to thermal expansion of typical ionogel membranes. The ionogel membranes developed in this work contain a framework of high porosity sPS gel filled with an ionic liquid that is later polymerized via free-radical polymerization. The resulting solid electrolyte membrane show improved thermal stability, good shape fixity, and negligible IL loss at high temperature. The electrolyte membrane also shows good electrochemical stability and adequate ionic conductivity due to high IL loading and high porosity of sPS gels.

Functionality of 1‐Butyl‐2,3‐Dimethylimidazolium Bromide (BMI‐Br) as a Solid Plasticizer in PEO‐Based Polymer Electrolyte for Highly Reliable Lithium Metal Batteries

“…The BMI‐Br would interact with LiTFSI salt based on the anion exchange in fabricating the electrolyte, forming the BMI‐TFSI salt within the PEO matrix. [ 61 ] Since the TFSI − is scavenged by BMI‐Br with creating BMI‐TFSI salt, the formation of [Li(TFSI) 2 ] −1 clusters would be reduced. [ 56 ] As a result, the reduced clustering can enhance the ion conductivity of Li + in the BMI‐Br‐CPE sample.…”

“…Previous similar work also showed that after anion exchange between 1‐ethyl‐3‐vinylimidazolium bromide and LiTFSI, forming VI‐TFSI and Li‐Br. [ 61 ] Here, BMI‐TFSI acts as an ionic liquid, while Li‐Br serves as a salt. [ 61 ] Schematic of the ionic conduction mechanisms in SPE and BMI‐Br‐CPEs is shown in Figure 4b.…”

The Influences of [EMIm]Ac Ionic Liquid for the Characteristics of Li‐Ion Batteries' Solid Biopolymer Blend Electrolyte Based on Cellulose Derivatives of MC/CMC Blend

“…The tensile strength for all series of the 10% LiClO 4 ‐complexed MC/CMC (50/50)‐based BBE doped with [EMIm]Ac are higher compared with previous polymer electrolytes which were reported. [ 46,58 ]…”

Preparation and properties of the aramid pulp/nitrile butadiene rubber composites with compatibilization of ionic liquids

“…Ionic liquids (ILs) are normally defined as compounds composed entirely of ions with melting point below 100 C. [21,22] An IL consists of an organic cation and an organic or inorganic anion, and is well known for its low vapor pressure, non-flammability, good thermal and chemical stability [23][24][25][26] and flexible structure design. [27] So far, ILs have been widely applied in the fields of analytical chemistry, [28,29] electrochemistry, [30][31][32] polymerization [33,34] and gas absorption/separation. [35][36][37][38] In the last decade, the potential applications as an effective and eco-friendly surface modification agent for fillers in rubber materials have also aroused great interest.…”