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Abstract Developing intelligent wearable energy storage devices that can endure harsh conditions is of interest for emerging applications in next‐generation electronics. Despite recent success in exploring functional materials for sophisticated self‐adaptivity in energy storage devices, it remains challenging to obtain both high reliability and superior performance. Herein, a novel method for fabricating micropatterned wearable thermoresponsive supercapacitors via direct ink writing (DIW) technique is reported. Thermal runaway of typical electrochemical storage devices with high power delivery capability can cause serious safety problems. The proposed temperature‐dependent structure works as self‐protection against the common thermal runaway issues of electrochemical energy storage devices. Such construction provides an automatic adjustment as high as 8 F g−1in specific capacitance, resulting in an overall heat reduction by up to 40%. The printing resolution of the electrodes (175 µm) is among the best in recently reported planar carbon‐based energy storage devices by DIW technique. Manufacturing‐related parameters such as time‐dependent printing speed and curing temperature are also investigated to fabricate this integrated design with varied materials and accuracy. This strategy shows tremendous promise for future intelligent energy storage devices.
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4D Printing of Stretchable Supercapacitors via Hybrid Composite Materials
Abstract Stretchable supercapacitors (SCs) have attracted significant attention in developing power‐independent stretchable electronic systems due to their intrinsic energy storage function and unique mechanical properties. Most current SCs are generally limited by their low stretchability, complicated fabrication process, and insufficient performance and robustness. This study presents a facile method to fabricate arbitrary‐shaped stretchable electrodes via 4D printing of conductive composite from reduced graphene oxide, carbon nanotube, and poly(3,4‐ethylenedioxythiophene) polystyrene sulfonate. The electrode patterns of an arbitrary shape can be deposited onto prestretched substrates by aerosol‐jet printing, then self‐organized origami (ridge) patterns are generated after releasing the substrates from holding stretchers due to the mismatched strains. The stretchable electrodes demonstrate superior mechanical robustness and stretchability without sacrificing its outstanding electrochemical performance. The symmetric SC prototype possesses a gravimetric capacitance of ≈21.7 F g−1at a current density of 0.5 A g−1and a capacitance retention of ≈85.8% from 0.5 to 5 A g−1. A SC array with arbitrary‐shaped electrodes is also fabricated and connected in series to power light‐emitting diode patterns for large‐scale applications. The proposed method paves avenues for scalable manufacturing of future energy‐storage devices with controlled extensibility and high electrochemical performance.
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- Award ID(s):
- 2024649
- PAR ID:
- 10454407
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials Technologies
- Volume:
- 6
- Issue:
- 1
- ISSN:
- 2365-709X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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