Lin Chuyuan, Yang Xuhui, Xiong Peixun, Lin Hui, He Lingjun, Yao Qi, Wei Mingdeng, Qian Qingrong, Chen Qinghua, Zeng Lingxing
Engineering Research Center of Polymer Green Recycling of Ministry of Education, College of Environmental Science and Engineering, Fujian Normal University, Fuzhou, Fujian, 350007, P. R. China.
School of Chemical Engineering, Sungkyunkwan University, Suwon-si, Gyeonggi-do, 16419, Republic of Korea.
Adv Sci (Weinh). 2022 Jul;9(21):e2201433. doi: 10.1002/advs.202201433. Epub 2022 May 26.
Aqueous Zn-ion batteries (AZIBs) have been recognized as promising energy storage devices due to their high theoretical energy density and cost-effectiveness. However, side reactions and Zn dendrite generation during cycling limit their practical application. Herein, ammonium acetate (CH COONH ) is selected as a trifunctional electrolyte additive to enhance the electrochemical performance of AZIBs. Research findings show that NH (oxygen ligand) and CH COO (hydrogenligand) with preferential adsorption on the Zn electrode surface can not only hinder Zn anode directly contact with active H O, but also regulate the pH value of the electrolyte, thus suppressing the parasitic reactions. Additionally, the formed SEI is mainly consisted of Zn (CO ) (OH) with a high Zn transference number, which could achieve a dendrite-free Zn anode by homogenizing Zn deposition. Consequently, the Zn||Zn symmetric batteries with CH COONH -based electrolyte can operate steadily at an ultrahigh current density of 40 mA cm with a cumulative capacity of 6880 mAh cm , especially stable cycling at -10 °C. The assembled Zn||MnO full cell and Zn||activated carbon capacitor also deliver prominent electrochemical reversibility. This work provides unique understanding of designing multi-functional electrolyte additive and promotes a long lifespan at ultrahigh current density for AZIBs.
水系锌离子电池（AZIBs）因其高理论能量密度和成本效益而被认为是很有前景的储能装置。然而，循环过程中的副反应和锌枝晶的产生限制了它们的实际应用。在此，选择醋酸铵（CH₃COONH₄）作为三功能电解质添加剂来提高AZIBs的电化学性能。研究结果表明，优先吸附在锌电极表面的NH₄⁺（氧配体）和CH₃COO⁻（氢配体）不仅可以阻碍锌阳极与活性H₂O直接接触，还可以调节电解质的pH值，从而抑制寄生反应。此外，形成的SEI主要由具有高锌迁移数的Zn₂(CO₃)(OH)₂组成，通过使锌沉积均匀化可以实现无枝晶的锌阳极。因此，基于CH₃COONH₄的电解质的Zn||Zn对称电池可以在40 mA cm⁻²的超高电流密度下稳定运行，累积容量为6880 mAh cm⁻²，特别是在-10°C下稳定循环。组装的Zn||MnO₂全电池和Zn||活性炭电容器也具有出色的电化学可逆性。这项工作为设计多功能电解质添加剂提供了独特的见解，并促进了AZIBs在超高电流密度下的长寿命。
