Core-shell fiber design boosts breakdown strength in organic polymer-based capacitors
Core-shell fiber design boosts breakdown strength in organic polymer-based capacitors lead image
Modern electrical devices and systems often demand high performance from their components. When it comes to energy storage, the greatest power density is found in capacitors, which provide additional benefits in pulsed systems. Capacitors must achieve both a high dielectric constant, which allows them to store more energy, and a high breakdown strength, so they do not fail and create a short circuit.
Capacitors made of polymer-based material are promising due in part to their high dielectric constants, but they are limited by their low breakdown strength. To overcome this limitation, Sun et al. developed core-shell structured fibers made from two organic polymers. The resulting dielectric film exhibits both desired traits and can be used in high-performance capacitors.
The authors selected two poly(vinylidene fluoride)-based polymers with a large difference in dielectric constant and used coaxial electrospinning to create copolymer fibers. This method allowed them to adjust the ratios of each polymer in the resulting fiber as well as their topological distribution in the resulting film.
“The resultant gradient polarization distribution leads to a significantly improved energy storage capacity,” said author Yao Wang. “Our simulation results confirm this is an effective strategy for high-performance electrostatic energy storage.”
In future work, the researchers will increase the efficiency of their material’s charge-discharge cycle and further study the breakdown mechanism with experimental and theoretical methods. They believe their research will spur the further development of polymer-based capacitors.
“I hope this work shall provide the community an alternative and effective strategy to achieve both high energy density and power density as well as long-term reliability under operation conditions,” said Wang.
Source: “Core-shell structured PVDF-based copolymer fiber design for high energy storage performance,” by Xindi Sun, Lingyu Zhang, Yantao Zheng, Lu Yang, Yuan Deng, and Yao Wang, Journal of Applied Physics (2022). The article can be accessed at https://doi.org/10.1063/5.0120895 .
This paper is part of the Special Collection Recognizing Women in Applied Physics, learn more here .
