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Today, the manufacturing industry increasingly faces the challenge of producing low volumes of personalized parts. As such, novel approaches have to be developed to address this new reality. To this end, a low-cost hybrid manufacturing method combining fused deposition modeling and electroforming to fabricate personalized high-precision metal parts is investigated. Three different approaches are studied and compared with each other in order to fabricate the mold assemblies employed for part electroforming. The potential of employing the chosen technique was evaluated by electroforming micro-hinges with various thicknesses and characterized mechanically. It is demonstrated that dimensions relevant to typical applications of micro-hinges can be achieved. In order to determine the capability of the developed manufacturing process, a functional X–Y micro-positioning stage is fabricated. Finally, the time and costs per part to manufacture personalized parts through the suggested method are studied based on the number of 3D printers deployed to print the molds during the electroforming. Manufacturing costs range from a few dollars to a few hundred dollars depending on the type of deployed 3D printer. [ABSTRACT FROM AUTHOR]

The energy storage behaviors of MnO2 for aqueous Zn‐MnO2 batteries mainly depend on the Zn2+/H+ intercalation but are limited by poor ion/electron migration dynamics and stability. Herein, a strategy is proposed that promoting proton migration kinetics ameliorates H+ storage activity by introducing Ni2+ into γ‐MnO2 (Ni‐MnO2). Ni2+ can lower the diffusion barrier of H+ and selectively induce the ion intercalation, thereby alleviating the electrostatic interaction with the lattice. Moreover, Ni2+ enables the adjacent [MnO6] octahedrons to have better electron conductivity. The Ni‐MnO2 exhibits superior rate performance (nearly four times specific capacity compared with MnO2) and ultra‐long‐cycle stability (100% of capacity retention after 11 000 cycles at 3.0 A g−1). The calculation indicates that the Ni‐MnO2 allows H+ migrate rapidly along the one‐dimensional tunnel due to reduction of the activation energy caused by Ni2+ regulating, thus achieving excellent reaction kinetics. This work brings great potential for the development of high‐performance aqueous Zn‐MnO2 batteries. [ABSTRACT FROM AUTHOR]

With the increasing demand for customization and personalization, the manufacturing industry faces new challenges related to cost-effective, low batch size production. Additive manufacturing (AM) is among the promising technology to address this problem. AM has however some limitations in metal structure fabrication, including high surface roughness, porosity, and poor mechanical properties. Electroforming on an AM mandrel could be a potential alternative solution for low batch production and complex structures with high aspect ratios. This process takes advantage of both high design freedom from AM and better structural control with electroforming. However, the uniformness, deposition quality, and end-geometry of the electrodeposition on a mandrel are not always guaranteed. In this paper, a method and an algorithm are proposed to improve the geometric precision of the deposition on the mandrel. The desired net-shape can be achieved by a corrected mandrel that takes the variable electrodeposition thickness into consideration. Therefore, the dimensional accuracy of the outer surface can be improved for applications requiring the dimensional accuracy of the outer shape, and a uniform part thickness is less important. In addition, a method that allows the forming of parts with controlled multiple thicknesses on the same mandrel is proposed. As one of the potential applications, the manufacturing of high-aspect-ratio flexures is demonstrated. [ABSTRACT FROM AUTHOR]

Aqueous rechargeable Zn–MnOx batteries are very attractive due to their low‐cost and high energy density. However, Mn(III) disproportionation and Jahn–Teller distortion can induce Mn(II) dissolution and irreversible phase changes, greatly deteriorating the cycling life. Herein, a multi‐valence cobalt‐doped Mn3O4 (Co‐Mn3O4) with high capacity and reversibility, which lies in the multiple roles of the various states of doped cobalt, is reported. The Co2+ doping between the phase change product δ‐MnO2 layer acts as a "structural pillar," and the Co4+ in the layer can increase the conductivity of Mn4+ and hold the high specific capacity. More importantly, Co ion (Co2+, Co3+) doping can effectively inhibit the Jahn–Teller effect in discharge products and promote ion diffusion. Using X‐ray absorption spectra results and density functional theory modelling, the multiple roles of doped cobalt are verified. Specifically, the Co‐Mn3O4 cathode shows high specific capacity of 362 mAh g–1 and energy density of 463.1 Wh kg–1 at 100 mA g–1. After 1100 cycles at 2.0 A g–1, the capacity retention rate reaches 80%. This work brings a new idea and approach to the design of highly reversible Mn‐based oxides cathode materials for Zn‐ion batteries. [ABSTRACT FROM AUTHOR]

Highlights: Ultra-thin CoNiO2 nanosheet with rich oxygen defects anchored on the vertically arranged Ni nanotube arrays (Od-CNO@Ni NTs) is successfully constructed. The Od-CNO@Ni NTs electrode delivers extraordinary electrochemical performance. The theoretical calculations reveal that oxygen defects effectively improve the electrochemical kinetics and the surface electronic state structure of Od-CNO @ Ni NTs, thus exhibiting strong OH − adsorption capacity.The alkaline zinc-based batteries with high energy density are becoming a research hotspot. However, the poor cycle stability and low-rate performance limit their wide application. Herein, ultra-thin CoNiO2 nanosheet with rich oxygen defects anchored on the vertically arranged Ni nanotube arrays (Od-CNO@Ni NTs) is used as a positive material for rechargeable alkaline Ni–Zn batteries. As the highly uniform Ni nanotube arrays provide a fast electron/ion transport path and abundant active sites, the Od-CNO@Ni NTs electrode delivers excellent capacity (432.7 mAh g−1) and rate capability (218.3 mAh g−1 at 60 A g−1). Moreover, our Od-CNO@Ni NTs//Zn battery is capable of an ultra-long lifespan (93.0% of initial capacity after 5000 cycles), extremely high energy density of 547.5 Wh kg−1 and power density of 92.9 kW kg−1 (based on the mass of cathode active substance). Meanwhile, the theoretical calculations reveal that the oxygen defects can enhance the interaction between electrode surface and electrolyte ions, contributing to higher capacity. This work opens a reasonable idea for the development of ultra-durable, ultra-fast, and high-energy Ni–Zn battery. [ABSTRACT FROM AUTHOR]