Ultrathin and Ultralight Zn Micromesh‐Induced Spatial‐Selection Deposition for Flexible High‐Specific‐Energy Zn‐Ion Batteries

• Published in: Advanced functional materials Vol. 31; no. 48
• Main Authors: Liu, Huaizhi, Li, Jinhao, Zhang, Xianan, Liu, Xiuxue, Yan, Yu, Chen, Fengjun, Zhang, Guanhua, Duan, Huigao
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc 01.11.2021
• Subjects: Deposition; Electrochemical machining; Electronic systems; Electronics; Flexibility; Flexible components; flexible electronics; Flux density; in situ observation system; Materials science; Microholes; Photolithography; Polyanilines; Portable equipment; Rechargeable batteries; spatial‐selection deposition; Specific energy; Stability; Substrates; Thickness; Vanadium oxides; Wettability; Zn dendrite; Zn micromesh; Zn‐ion batteries
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.202106550

Ultraflexible and ultralight rechargeable aqueous Zn‐ion batteries (ZIBs) with the merits of environmental benignity and high security arise as promising candidates for flexible electronic systems. Nowadays, the energy density and cyclical stability of ZIBs on metal‐based rigid substrates reach a satisfactory level, while the inflexible substrates severely prevent them from widespread commercial adoption in portable electronics. Although flexible substrates‐engineered devices burgeon, the development of flexible ZIBs with high specific energy still faces great challenges. Herein, a flexible ultrathin and ultralight Zn micromesh (thickness of 8 µm and areal density of 4.9 mg cm−2) with regularly aligned microholes is fabricated via combining photolithography with electrochemical machining. The unique microholes‐engineered Zn micromesh presents excellent flexibility, enhanced mechanical strength, and better wettability. Moreover, numerical simulations in COMSOL and in situ microscopic observation system certify the induced spatial‐selection deposition of Zn micromesh. Accordingly, aqueous ZIBs constructed with polyaniline‐intercalated vanadium oxide cathode and Zn micromesh anode demonstrate exceptional high‐rate capability (67.6% retention with 100 times current density expansion) and cyclical stability (maintaining 87.6% after 1000 cycles at 10.0 A g−1). Furthermore, the assembled pouch cell displays superb flexibility and durability under different scenarios, indicating great prospects in high‐energy ZIBs and flexible electronics. A flexible ultrathin and ultralight Zn micromesh with regularly aligned microholes is fabricated through highly mature and scalable techniques. The unique microholes‐engineered Zn micromesh presents excellent mechanical and electrical properties. Numerical simulations and in situ microscopic observation system certify the induced spatial‐selection deposition into inner walls of microholes. Furthermore, the assembled pouch cell demonstrates superb flexibility and long‐lasting stability.