Effective Solution toward the Issues of Zn-Based Anodes for Advanced Alkaline Ni-Zn Batteries

Strategies Toward Stretchable Aqueous Zn-based Batteries for Wearable Electronics from Components to Devices

Recently, aqueous Zn-based batteries (AZBs) are receiving increased attention in wearable and implantable electronics due to the low cost, high safety, high eco-efficiency, and relatively high energy density. However, it is still a big challenge to develop stretchable AZBs (SAZBs) which can be conformally folded, crumpled, and stretched with human body motions. Although a lot of efforts have been dedicated to constructions of SAZBs, a comprehensive review which focuses on summarizing stretchable materials, device configurations and challenges of SAZBs is needed. Herein, this review attempts to critically review the latest developments and progress in stretchable electrodes, electrolytes, packaging materials and device configurations in detail. Furthermore, these challenges and potential future research directions in the field of SAZBs are also discussed.

Achieving desirable charge transport by porous frame engineering for superior 3D printed rechargeable Ni-Zn alkaline batteries

Rechargeable 3D printed batteries with extraordinary electrochemical potential are typical contenders as one of the promising energy storage systems. Low-cost, high-safety, and excellent rechargeable aqueous alkaline batteries have drawn extensive interest. But their practical applications are severely hampered by poor charge carrier transfer and limited electrochemical activity at high loading. Herein, we report a unique structure-based engineering strategy in 3D porous frames using a feasible 3D printing technique and achieve 3D printed full battery devices with outstanding electrochemical performance. By offering a 3D porous network to provide prominently stereoscopic support and optimize the pore structure of electrodes, the overall charge carrier transport of engineered 3D printed Ni-Zn alkaline batteries (E3DP-NZABs) is greatly enhanced, which is directly demonstrated through a single-wired characterization platform. The obtained E3DP-NZABs deliver a high areal capacity of 0.34 mA h cm-2 at 1.2 mA cm-2, and an outstanding capacity retention of 96.2% after 1500 cycles is also exhibited with an optimal electrode design. Particularly, parameter changes such as a decrease in pore sizes and an increase in 3D network thickness are favorable to resultant electrochemical performance. This work may represent a vital step to promote the practical application progress of alkaline batteries.

Alkaline Ni-Zn Microbattery Based on 3D Hierarchical Porous Ni Microcathode with High-Rate Performance

Miniaturized energy storage devices with superior performance and compatibility with facile fabrication are highly desired in smart microelectronics. Typical fabrication techniques are generally based on powder printing or active material deposition, which restrict the reaction rate due to the limited optimization of electron transport. Herein, we proposed a new strategy for the construction of high-rate Ni-Zn microbatteries based on a 3D hierarchical porous nickel (Ni) microcathode. With sufficient reaction sites from the hierarchical porous structure as well as excellent electrical conductivity from the superficial Ni-based activated layer, this Ni-based microcathode is featured with fast-reaction capability. By virtue of facile electrochemical treatment, the fabricated microcathode realized an excellent rate performance (over 90% capacity retention when the current density increased from 1 to 20 mA cm^-2). Furthermore, the assembled Ni-Zn microbattery achieved a rate current of up to 40 mA cm^-2 with a capacity retention of 76.9%. Additionally, the high reactivity of the Ni-Zn microbattery is also durable in 2000 cycles. This 3D hierarchical porous Ni microcathode, as well as the activation strategy, provides a facile route for the construction of microcathodes and enriches high-performance output units for integrated microelectronics.