Cationic cellulose nanofiber solid electrolytes: A pathway to high lithium-ion migration and polysulfide adsorption for lithium-sulfur batteries

Chenhao Ji; Shuanglin Wu; Feng Tang; Yanting Yu; Fenglin Hung; Qufu Wei

doi:10.1016/j.carbpol.2024.122075

Cationic cellulose nanofiber solid electrolytes: A pathway to high lithium-ion migration and polysulfide adsorption for lithium-sulfur batteries

Carbohydr Polym. 2024 Jul 1:335:122075. doi: 10.1016/j.carbpol.2024.122075. Epub 2024 Mar 20.

Authors

Chenhao Ji¹, Shuanglin Wu¹, Feng Tang¹, Yanting Yu¹, Fenglin Hung², Qufu Wei¹

Affiliations

¹ Key Laboratory of Eco-Textiles, Ministry of Education, Jiangnan University, Wuxi 214122, China.
² Key Laboratory of Eco-Textiles, Ministry of Education, Jiangnan University, Wuxi 214122, China.. Electronic address: flhuang@jiangnan.edu.cn.

PMID: 38616096
DOI: 10.1016/j.carbpol.2024.122075

Abstract

Polyethylene oxide (PEO) solid electrolytes, acknowledged for their safety advantages over liquid counterparts, confront inherent challenges, including low ionic conductivity, restricted lithium ion migration, and mechanical fragility, notably pronounced in lithium‑sulfur batteries due to the polysulfide shuttling phenomenon. To address these limitations, we integrate a quaternary ammonium cation-modified cellulose (QACC) nanofiber, electrospun with cellulose acetate (CA) from recycled cigarette filters, into the PEO electrolyte matrix. The nitrogen atom within the quaternary ammonium group exhibits a pronounced affinity for polysulfide compounds, effectively curtailing polysulfide migration. Concurrently, Lewis acid-base interactions between quaternary ammonium groups and lithium salt anions facilitate the release of additional Li⁺, achieving a lithium-ion transference number 1.5 times higher than its pure PEO counterpart. Furthermore, the introduction of a larger trifluoromethanesulfonimide (TFSI) group on the QACC macromolecule (TFSI-QACC) disrupts the ordered arrangement of PEO macromolecules, resulting in a noteworthy enhancement in ionic conductivity, reaching 2.07 × 10^-4 S cm^-1 at 60 °C, thus addressing the challenge of low PEO electrolyte conductivity. Moreover, the nanofiber enhances the mechanical strength of the PEO electrolyte from 0.49 to 7.50 MPa, mitigating safety concerns related to lithium dendrites puncturing the electrolyte. Consequently, the composite PEO demonstrates exemplary performance in lithium symmetrical batteries, enduring 500 h of continuous operation and completing 100 cycles at both room and elevated temperatures. This integrated approach, transitioning from waste to wealth, adeptly addresses a spectrum of challenges in the efficiency of solid-state electrolytes, holding considerable promise for advancing lithium‑sulfur battery technology.

Keywords: Cellulose; Electrospinning; Lithium‑sulfur battery; PEO solid electrolytes; Utilize recycled cigarette filters.