Wang Hanbing, Liu Xuan, Zhong Junsen, Du Lingyu, Yun Shan, Zhang Xiaolong, Gao Yanfeng, Kang Litao
College of Environment and Materials Engineering, Yantai University, Yantai, 264005, China.
Key Laboratory for Palygorskite Science and Applied Technology of Jiangsu Province, Huaiyin Institute of Technology, Huai'an, 223003, China.
Small. 2024 Mar;20(13):e2306947. doi: 10.1002/smll.202306947. Epub 2023 Nov 16.
As one of promising candidates for large-scale energy-storage systems, Zn-I aqueous battery exhibits multifaceted advantages including low cost, high energy/powder density, and intrinsic operational safety, but also suffers from fast self-discharge and short cycle/shelf lifespan associating with I shuttle, Zn dendrite growth, and corrosion. In this paper, the battery's self-discharge rate is successfully suppressed down to an unprecedent level of 17.1% after an ultralong shelf-time of 1 000 h (i.e., 82.9% capacity retention after 41 days open-circuit storage), by means of manipulating solvation structures of traditional ZnSO electrolyte via simply adjusting electrolyte concentration. Better yet, the optimized 2.7 m ZnSO electrolyte further prolongs the cycle lifespan of the battery up to >10 000 and 43 000 cycles at current density of 1 and 5 A g, respectively, thanks to the synthetic benefits from reduced free water content, modified solvation structure and lowered I dissolution in the electrolyte. With both long lifespan and ultralow self-discharge, this reliable and affordable Zn-I battery may provide a feasible alternative to the centuries-old lead-acid battery.
作为大规模储能系统中颇具潜力的候选者之一，锌-碘水系电池具有多方面优势，包括低成本、高能量/功率密度以及内在的运行安全性，但也存在快速自放电以及与碘穿梭、锌枝晶生长和腐蚀相关的短循环/储存寿命等问题。在本文中，通过简单调节电解质浓度来操控传统硫酸锌电解质的溶剂化结构，在长达1000小时的超长储存时间后（即开路储存41天后容量保持率为82.9%），电池的自放电率成功被抑制至前所未有的17.1%水平。更妙的是，优化后的2.7 m硫酸锌电解质分别在1和5 A g的电流密度下，将电池的循环寿命进一步延长至超过10000次和43000次，这得益于自由水含量降低、溶剂化结构改变以及电解质中碘溶解减少所带来的综合益处。这种具有长寿命和超低自放电特性的可靠且经济实惠的锌-碘电池，可能为已有数百年历史的铅酸电池提供一种可行的替代方案。
