Mass‐Producible, Quasi‐Zero‐Strain, Lattice‐Water‐Rich Inorganic Open‐Frameworks for Ultrafast‐Charging and Long‐Cycling Zinc‐Ion Batteries

• Published in: Advanced materials (Weinheim) 2020-11, Vol.32 (45), p.n/a
• Main Authors: Yang, Xin, Deng, Wenzhuo, Chen, Ming, Wang, Yaobing, Sun, Chuan‐Fu
• Format: Article
• Language: English
• Subjects: Cadmium; Cathodes; Charging; Chemical synthesis; Cycles; Diffusion rate; Electrode materials; Energy storage; Flux density; inorganic open‐framework; Materials science; Storage batteries; ultrafast charging; zero‐strain; Zinc; zinc‐ion batteries
• ISSN: 0935-9648; 1521-4095
• DOI: 10.1002/adma.202003592

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 Zn2+‐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−1) and energy density (193.8 Wh kg−1 or 513 Wh L−1), is reported. The abundant lattice waters functioning as a “charge shield” enable a low Zn2+‐migration energy barrier, (0.66 eV) even close to that of Li+ within LiFePO4. 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−1 at 107 Wh kg−1). Equally important, the IOF exhibits a quasi‐zero‐strain feature (