Li Chaowei, Wang Wenhui, Luo Jie, Zhuang Wubin, Zhou Jianxian, Liu Shizuo, Lin Lin, Gong Wenbin, Hong Guo, Shao Zhipeng, Du Jimin, Zhang Qichong, Yao Yagang
National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Jiangsu Key Laboratory of Artificial Functional Materials, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China.
Henan Key Laboratory of New Optoelectronic Functional Materials, College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang, Henan, 455000, China.
Adv Mater. 2024 May;36(21):e2313772. doi: 10.1002/adma.202313772. Epub 2024 Mar 1.
Fiber-shaped aqueous zinc-ion batteries (FAZIBs) with intrinsic safety, highcapacity, and superb omnidirectional flexibility hold promise for wearable energy-supply devices. However, the interfacial separation of fiber-shaped electrodes and electrolytes caused by Zinc (Zn) stripping process and severe Zn dendrites occurring at the folded area under bending condition seriously restricts FAZIBs' practical application. Here, an advanced confinement encapsulation strategy is originally reported to construct dual-layer gel electrolyte consisting of high-fluidity polyvinyl alcohol-Zn acetate inner layer and high-strength Zn alginate outer layer for fiber-shaped Zn anode. Benefiting from the synergistic effect of inner-outer gel electrolyte and the formation of solid electrolyte interphase on Zn anode surface by lysine additive, the resulting fiber-shaped Zn-Zn symmetric cell delivers long cycling life over 800 h at 1 mA cm with dynamic bending frequency of 0.1 Hz. The finite element simulation further confirms that dual-layer gel electrolyte can effectively suppress the interfacial separation arising from the Zn stripping and bending process. More importantly, a robust twisted fiber-shaped Zn/zinc hexacyanoferrate battery based on dual-layer gel electrolyte is successfully assembled, achieving a remarkable capacity retention of 97.7% after bending 500 cycles. Therefore, such novel dual-layer gel electrolyte design paves the way for the development of long-life fiber-shaped aqueous metal batteries.
具有本质安全性、高容量和出色全方位柔韧性的纤维状水系锌离子电池（FAZIBs）在可穿戴能量供应设备方面具有广阔前景。然而，锌（Zn）剥离过程导致的纤维状电极与电解质之间的界面分离，以及弯曲条件下折叠区域出现的严重锌枝晶，严重限制了FAZIBs的实际应用。在此，首次报道了一种先进的限域封装策略，用于构建由高流动性聚乙烯醇 - 醋酸锌内层和高强度海藻酸锌外层组成的双层凝胶电解质，用于纤维状锌阳极。得益于内外层凝胶电解质的协同效应以及赖氨酸添加剂在锌阳极表面形成的固体电解质界面，所得的纤维状锌 - 锌对称电池在1 mA cm下以0.1 Hz的动态弯曲频率可提供超过800小时的长循环寿命。有限元模拟进一步证实，双层凝胶电解质可以有效抑制锌剥离和弯曲过程中产生的界面分离。更重要的是，基于双层凝胶电解质成功组装了一种坚固的扭曲纤维状锌/六氰合铁酸锌电池，在弯曲500次循环后实现了97.7%的显著容量保持率。因此，这种新颖的双层凝胶电解质设计为长寿命纤维状水系金属电池的发展铺平了道路。
