Coaxial fiber-shaped supercapacitors with short charge carrier diffusion paths are highly desirable as high-performance energy storage devices for wearable electronics. However, the traditional approaches based on the multistep fabrication processes for constructing the fiber-shaped energy device still encounter persistent restrictions in fabrication procedure, scalability, and mechanical durability. To overcome this critical challenge, an all-in-one coaxial fiber-shaped asymmetric supercapacitor (FASC) device is realized by a direct coherent multi-ink writing three-dimensional printing technology via designing the internal structure of the coaxial needles and regulating the rheological property and the feed rates of the multi-ink. Benefitting from the compact coaxial structure, the FASC device delivers a superior areal energy/power density at a high mass loading, and outstanding mechanical stability. As a conceptual exhibition for system integration, the FASC device is integrated with mechanical units and pressure sensor to realize high-performance self-powered mechanical devices and monitoring systems, respectively.

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Rechargeable aqueous Zn‐ion batteries (ZIBs) are always regarded as a promising energy storage device owing to their higher safety and durability. However, two problems have become the main trouble for the practical application of ZIBs such as the dendrite growth of Zn metal anode in electrolyte and the freezing of water solvent at low temperature. Herein, to overcome these challenges, a new strategy, multi‐component crosslinked hydrogel electrolyte, is proposed to inhibit Zn dendrites and realize low temperature environmental adaptability for ZIBs. Benefitting from the superior inhibition effect of the polyacrylamide and dimethyl sulfoxide (DMSO) on Zn dendrites, the coulombic efficiency of the symmetric cell of ≈99.5% is achieved during the Zn plating/stripping over 1 300 h, and the assembled full‐cell demonstrates the large specific capacity of 265.2 mAh g‐1 and high cyclic stability with the capacity retention of 95.27% after 3 000 cycles. In addition, the full‐cell delivers stable operation at a wide temperature range, from 60 to −40 °C, due to the introduction of additive DMSO. This work provides an inspired strategy and novel opportunities to realize a dendrite‐free and wide‐temperature rechargeable aqueous Zn‐ion energy storage system.

Wireless capsule endoscopy (WCE) offers a feasible noninvasive way to detect the whole gastrointestinal (GI) tract and revolutionizes the diagnosis technology. However, compared with wired endoscopies, the limited working time, the low frame rate, and the low image resolution limit the wider application. The progress of this new technology is reviewed in this paper, and the evolution tendencies are analyzed to be high image resolution, high frame rate, and long working time. Unfortunately, the power supply of capsule endoscope (CE) is the bottleneck. Wireless power transmission (WPT) is the promising solution to this problem, but is also the technical challenge. Active CE is another tendency and will be the next geneion of the WCE. Nevertheless, it will not come true shortly, unless the practical locomotion mechanism of the active CE in GI tract is achieved. The locomotion mechanism is the other technical challenge, besides the challenge of WPT. The progress about the WPT and the active capsule technology is reviewed.

As one of the most promising candidates in wearable energy storage devices, aqueous fibrous zinc metal batteries (AFZMBs) remain limited by some severe challenges, such as short life span and unstable capacity performance, etc. In this work, the stability of AFZMB is extended by fabricating an innovative stratified deposition framework (SDF) anode. The as‐prepared SDF electrode can achieve a stratified deposition of Zn metals from the bottom layer to the top layer due to the different overpotentials and binding energy of Zn deposition. Compared with commercial Zn fibers, this dexterous structure provides enough deposition space for Zn metals between the separator and the electrode, dramatically alleviating conventional dendrite puncture and prolonging life expectancy by an order of magnitude. It is found that SDF/AFZMB exhibits a long circulation of 2000 cycles with 89.0% capacity retention at 5 C with superior flexibility, demonstrating potential for application in future wearable electronics.