Synthesis of Li Conductive Polymer Layer on 3D Structured S Cathode by Photo-Polymerization for Li–S Batteries

Abstract

The dissolution of lithium polysulfide (Li2Sx, 4 ≤ x ≤ 8, LiPS) during charge/discharge testing is a critical issue hindering the practical application of lithium-sulfur batteries (LSBs). To suppress LiPS dissolution, we propose a facile method to fabricate a Li-ion-conductive polymer layer by photopolymerization. The electrochemical performance of LSBs was investigated by preparing small pouch cells containing a three-dimensional (3D) structured sulfur-based cathode that either was or was not layered with the new polymer. Analysis of the electrolyte in the LSB pouch cell by UV-Vis spectroscopy revealed that a 3D S cathode with polymer layer shows a good discharge capacity of 535 mA h g-1 and a coulombic efficiency (CE) of over 96% after 40 cycles. In comparison, the 3D S cathode without a polymer layer has a poor discharge capacity of 389 mA h g-1 and a CE of over 22% after 40 cycles. The dissolution suppressing ability of our new polymer layer demonstrates promise for the practical application of LSBs.

Nitrogen/sulfur dual-doped micro-mesoporous hierarchical porous carbon as host for Li-S batteries

“…Because of high theoretical specific energy (2,600 Wh kg −1 ), non-toxicity and abundant natural reserves, Li-S batteries are expected to become the next generation of new energy storage systems ( Chen et al, 2022 ; Wang et al, 2022 ). Lots of interesting results on Li-S batteries have been reported ( Kim et al, 2020 ; Ahn et al, 2022 ; Qian et al, 2022 ; Wei et al, 2022 ; Yu et al, 2022 ; Zhao et al, 2022 ). However, Li-S batteries still face two important challenges.…”

Facile one-pot synthesis of biomass-derived activated carbon as an interlayer material for a BAC/PE/Al2O3 dual coated separator in Li–S batteries

“…Sulfur is advantageous as a cathode material because of its abundance, low cost (<30 $ per ton), environmental friendliness, high theoretical capacity (1675 mA h g −1 ), and approximately 3-5 times higher gravimetric energy density (2600 W h kg −1 ) than commercial LIB. [23][24][25][26][27][28] Despite the materials and electrochemical advantages of a sulfur cathode, commercialization of LSB is limited owing to several critical issues like (1) the low utilization of active material in sulfur cathodes due to low electrical conductivity of elemental S, (2) dissolution of lithium polysulde (LiPS) from cathode to a liquid electrolyte leading to the shuttle effect, (3) volume exchange of elemental S (∼80%), and (4) safety issues in Li dendrite growth during the charge and discharge process. To address these limitations, several studies have focused on various solutions, including immobilization of LiPS using porous cathode additives, [29][30][31] lithium penetrated polymer layer on the cathode, [32][33][34] multi-functional separators, [35][36][37] and electrolyte additives [38][39][40] for better formation of surface electrolyte interface on the surface of Li anodes.…”

Improved Cycling Performance Using a Poly-2-Acrylamido-2-Methylpropanesulfonic Acid (AMPS)-Based Crosslinked Gel Polymer on a Sulfur Cathode for Inhibiting the Dissolution of Polysulfide in a Li–S Battery

“…Previously, our group reported stable cycling performance without LiPS dissolution in DOL-DME-based electrolytes by covering an S/KB composite cathode with electropolymerized polypyrrole films 9,10 or by incorporating an anionic functional group of TFSI − or the sulfonyl group of SO 3 − in poly-2-acrylamido-2methylpropanesulfonic acid (AMPS)-based polymer films. 11,12 LiPS dissolution may be restricted by electrostatic interactions between the anionic functional groups in the film and negatively charged LiPSs.…”