A Supramolecular Binder for High-Lifespan Silicon Suboxide Anodes in Lithium-Ion Batteries

Gong, Yifan; Zhang, Peng; Du, Yanrui; Hu, Xinyao; Mu, Pengzhou; Zhang, Huanrui; Wang, QingFu

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J. Electrochem. Sci. Technol > Accepted Articles

Research Article

DOI: https://doi.org/10.33961/jecst.2026.00479 [Accepted]
Published online August 21, 2026.

A Supramolecular Binder for High-Lifespan Silicon Suboxide Anodes in Lithium-Ion Batteries

Yifan Gong^1,2, Peng Zhang², Yanrui Du², Xinyao Hu², Pengzhou Mu², Huanrui Zhang², QingFu Wang¹

¹School of Polymer Science and Engineering, Qingdao University of Science & Technology, Qingdao 266042, China
²Qingdao Industrial Energy Storage Research Institute, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Science, Qingdao 266101, China

Correspondence: Pengzhou Mu,
Email: mupz@qibebt.ac.cn
Huanrui Zhang,
Email: zhanghr@qibebt.ac.cn
QingFu Wang,
Email: wangqf@qust.edu.cn

Received: 19 May 2026 • Accepted: 17 August 2026

Abstract

Silicon suboxide (SiOx) anodes with high theoretical specific capacities are promising for developing next-generation high-energy-density lithium-ion batteries. Nevertheless, they suffer from poor cycling stability, mainly owing to severe volume variation, electrode structural degradation, unstable solid electrolyte interphase (SEI), and continuous electrolyte decomposition during repeated lithiation/delithiation processes. Herein, we develop a supramolecular polymer (denoted as PAUN) binder, consisting of sodium acrylate segments and fluorinated polylysine-derived macromolecular units. PAUN binder integrates multiple functional motifs, including abundant sodium carboxylate groups and amide groups for strong anchoring and/or dynamic hydrogen-bonding networks. Compared with conventional poly(acrylic acid) (PAA), PAUN binder exhibits enhanced mechanical robustness, stronger electrode adhesion, improved elastic recovery, and better electrolyte wettability. These features enable SiOx electrodes to accommodate repeated volume fluctuation while maintaining electrode integrity. Moreover, PAUN promotes the formation of a thinner, more uniform, and LiF-rich SEI layer, thereby suppressing continuous electrolyte decomposition and reducing interfacial impedance growth. Consequently, SiOx anodes employing PAUN binder deliver a high charge capacity of 1088.1 mAh g⁻¹ after 200 cycles at 0.5 C with a capacity retention of 88.9%, evidently outperforming SiO_X anodes employing PAA binder. This supramolecular binder design provides a facile and effective strategy for stabilizing high-capacity SiOx anodes toward practical lithium-ion battery applications.

Keywords: Lithium-ion Batteries, Silicon Suboxide Anodes, Polymer Binder