Self-healing polymer materials for the next generation of high-temperature power capacitors

Polymer-based power capacitors have long struggled with combining high temperatures with good breakdown strength and reliability. With the increasing adoption of wide-band-gap semiconductors in convertors for e-mobility, HVDC, etc, there is a need for high voltage capacitors that can withstand ever higher temperatures, without compromising on reliability or breakdown voltage. We present a new class of polymer dielectric material, developed in collaboration between the DTU Department of Chemical and Biochemical Engineering and the SDU Centre for Industrial Electronics based on self-healing cross-linked polymer networks. These materials can self-heal at temperatures well beyond BOPP, exhibiting increased breakdown voltages at elevated temperatures and the ability to heal post-breakdown. If implemented in converters, these materials would result in substantial gains in energy efficiency and device lifetime.