Ultrahigh energy storage density at low operating field strength achieved in multicomponent polymer dielectrics with hierarchical structure

• Published in: Composites science and technology 2021-01, Vol.201, p.108557, Article 108557
• Main Authors: Chen, Jie, Wang, Yifei, Dong, Jiufeng, Chen, Weixing, Wang, Hong
• Format: Article
• Language: English
• Subjects: Charge efficiency; Charge–discharge efficiency; Dielectric strength; Dielectrics; Electric fields; Energy storage; Energy storage density; Field strength; Low operating field strength; Multicomponent-polymer dielectrics; Nanofibers; Nanowires; Polymer films; Polymer matrix composites; Polymers; Polymethyl methacrylate; Structural hierarchy; Structure design; Studies; Synergistic effect; Thermal energy; Thin films
• ISSN: 0266-3538; 1879-1050
• DOI: 10.1016/j.compscitech.2020.108557

Dielectric composites with excellent capacitive energy storage capabilities have great potential applications in energy storage capacitors operating efficiently at relatively low field strengths. Herein, unlike the traditional methods via the introduction of fillers including randomly distributed ceramic nanofibers and aligned nanowires arrays into the monolayer films are simply to increase the energy storage density (Ue), both Ue and charge–discharge efficiency (η) at low electric field strengths have been improved in tri-layered all-polymer films owing to the synergistic effect of multiple interbedded interfaces and deliberately modulation of linear dielectric poly(methyl methacrylate) (PMMA) contents. The effects of film structure on the energy storage capabilities have been comparatively discussed. Consequently, an ultrahigh Ue of 15 J cm−3 accompanied with great η of 76.5% has been delivered in the resulting tri-layered film via optimizing the PMMA content (30 wt%) of out layers at 350 MV m−1, surpassing the energy storage upper limits of the reported polymer dielectrics that show the Ue of ~12 J cm−3 and η of ~70% at comparable electric fields of 310–380 MV m−1. Along with high pulsed power density, multicomponent polymer dielectrics with hierarchically structure provide an effective paradigm for achieving the low operating field strength applications of capacitive energy storage devices with excellent energy storage capability. [Display omitted] •Multicomponent polymer dielectrics with hierarchical structure were elaborately prepared.•The improved properties were achieved by the multiple interlaminar interfaces and linear PMMA contents of out layers.•Ultrahigh Ue of 15 J cm-3 along with great η of 76.5% at 350 MV m−1 has been delivered in the optimized film (30 wt.%).•The excellent energy storage performance exceeds the upper limits of Ue of ~12 J cm-3 and η of ~70%.