An Aqueous Binder for High-Areal-Capacity Fe<sub>3</sub>O<sub>4</sub>-Based Anodes in Lithium-Ion Batteries
Zeheng Li, Yingchong Huang, Zhengwei Wan, Xiaomin Zeng, Tuyuan Zhu, Wei Jiang, Zhuoying Wu, Xuehui Gao, Min Ling, Chengdu Liang
Abstract
Binders have an important effect on improving the electrochemical performance of lithium-ion batteries, but binders are yet to receive much attention in Fe3O4-based electrodes. Herein, polyacrylamide (PAM) is developed as an aqueous binder for high-capacity carbon-coated Fe3O4 (Fe3O4@C-PAM) anodes. Benefitting from its strong adhesion strength and robust mechanical properties, PAM as a binder, besides effectively tolerating the huge volume changes of Fe3O4, keeps the integrity of the Fe3O4-based electrode during cycling. In addition, compared with a polyvinylidene difluoride (PVDF) binder, the water-soluble PAM binder enables the fabrication of Fe3O4-based electrodes in a green and low-cost process. These appealing characteristics lead to better electrochemical performances of Fe3O4@C-PAM anodes than those of Fe3O4@C-PVDF anodes. Moreover, the PAM binder is effective for high Fe3O4@C loading electrode (6.8 mg cm–2), enabling a high areal capacity of 8.06 mA h cm–2.