Du Weidong, Jiang Xiaoping, Li Shiteng, Cao Piting, Li Linjie, Feng Deshi, Huang Xiaojie, Xu Fengzhao, Ye Chuangen, Liang Xiu, Zhang Jing, Gao Meng, Li Yong
Advanced Materials Institute, School of Materials Science and Technology, Qilu University of Technology (Shandong Academy of Sciences), Jinan, 250014, China.
College of Materials and Chemical Engineering, Heilongjiang Institute of Technology, Harbin, 150006, China.
Small Methods. 2024 Dec;8(12):e2400249. doi: 10.1002/smtd.202400249. Epub 2024 Apr 18.
Aqueous zinc-ion batteries (AZIBs) directly using zinc metal anodes are promising candidates for grid-scale energy storage systems due to their intrinsic high theoretical capacity, high safety, and environmental friendliness. However, the uncontrolled dendrite growth and water-triggered side reactions seriously plague its practical application. Herein, a cost-effective and green additive, maltodextrin (MD) is presented, to simultaneously guide the smooth Zn deposition and inhibit the occurrence of water-related side reactions. Combing experimental characterizations and theoretical calculations shows that the MD molecules could reconstruct the Helmholtz plane, induces a preferential growth of zinc along the (002) plane, and the optimized regulation of the Zn diffusion path and deposition location also results in the formation of fine-grained Zn deposition layers, thereby inhibiting dendrite growth. In addition, MD molecules readily adsorb to the zinc anode surface, which isolates water molecules from direct contact with the zinc metal, reducing hydrogen precipitation reactions and inhibiting the formation of by-products. Consequently, the Zn||Zn symmetric cell with MD achieves ultra-long stable cycles of up to 5430 h at 1 mA cm and 1 mA h cm, and the Cu||Zn asymmetric cell can stable cycle 1000 cycles with an average coulomb efficiency of 99.78%.
直接使用锌金属负极的水系锌离子电池（AZIBs）因其固有的高理论容量、高安全性和环境友好性，是电网规模储能系统的理想候选者。然而，不受控制的枝晶生长和水引发的副反应严重困扰其实际应用。在此，提出了一种具有成本效益的绿色添加剂——麦芽糊精（MD），以同时引导锌的平滑沉积并抑制与水相关的副反应的发生。结合实验表征和理论计算表明，MD分子可以重构亥姆霍兹平面，诱导锌沿（002）平面优先生长，并且对锌扩散路径和沉积位置的优化调控还导致形成细晶粒的锌沉积层，从而抑制枝晶生长。此外，MD分子易于吸附到锌负极表面，将水分子与锌金属直接接触隔离开来，减少析氢反应并抑制副产物的形成。因此，含有MD的Zn||Zn对称电池在1 mA cm 和1 mA h cm 条件下实现了长达5430 h的超长稳定循环，而Cu||Zn不对称电池可以稳定循环1000次，平均库仑效率为99.78%。
