Yang Xin, Deng Wenzhuo, Chen Ming, Wang Yaobing, Sun Chuan-Fu
CAS Key Laboratory of Design and Assembly of Functional Nanostructures and Fujian Key Laboratory of Nanomaterials, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, 350002, P.R. China.
University of Chinese Academy of Sciences, Beijing, 100039, P.R. China.
Adv Mater. 2020 Nov;32(45):e2003592. doi: 10.1002/adma.202003592. Epub 2020 Oct 5.
Low-cost and high-safety aqueous Zn-ion batteries are an exceptionally compelling technology for grid-scale energy storage. However, their development has been plagued by the lack of stable cathode materials allowing fast Zn -ion insertion and scalable synthesis. Here, a lattice-water-rich, inorganic-open-framework (IOF) phosphovanadate cathode, which is mass-producible and delivers high capacity (228 mAh g ) and energy density (193.8 Wh kg or 513 Wh L ), is reported. The abundant lattice waters functioning as a "charge shield" enable a low Zn -migration energy barrier, (0.66 eV) even close to that of Li within LiFePO . This fast intrinsic ion-diffusion kinetics, together with nanostructure effect, allow the achievements of ultrafast charging (71% state of charge in 1.9 min) and an ultrahigh power density (7200 W kg at 107 Wh kg ). Equally important, the IOF exhibits a quasi-zero-strain feature (<1% lattice change upon (de)zincation), which ensures ultrahigh cycling durability (3000 cycles) and Coulombic efficiencies of 100%. The cell-level energy and power densities reach ≈90 Wh kg and ≈3320 W kg , far surpassing commercial lead-acid, Ni-Cd, and Ni-MH batteries. Lattice-water-rich IOFs may open up new opportunities for exploring stable and fast-charging Zn-ion batteries.
低成本且高安全性的水系锌离子电池是用于电网规模储能的极具吸引力的技术。然而，其发展一直受到缺乏能够实现快速锌离子嵌入和可扩展合成的稳定阴极材料的困扰。在此，报道了一种富含晶格水的无机开放框架（IOF）磷酸钒酸盐阴极，它可大规模生产，具有高容量（228 mAh g）和能量密度（193.8 Wh kg或513 Wh L）。大量作为“电荷屏蔽”的晶格水使得锌离子迁移能垒较低（0.66 eV），甚至接近磷酸铁锂中锂离子的迁移能垒。这种快速的本征离子扩散动力学，连同纳米结构效应，使得能够实现超快充电（1.9分钟内充电至71%的充电状态）和超高功率密度（在107 Wh kg时为7200 W kg）。同样重要的是，该IOF表现出准零应变特性（去锌化/锌化时晶格变化<1%），这确保了超高的循环耐久性（3000次循环）和100%的库仑效率。电池级的能量和功率密度分别达到约90 Wh kg和约3320 W kg，远远超过商用铅酸、镍镉和镍氢电池。富含晶格水的IOF可能为探索稳定且快速充电的锌离子电池开辟新机遇。
