Review of Polymer‐Based Nanodielectric Exploration and Film Scale‐Up for Advanced Capacitors

Abstract

The uprising demands for electrical power and electrification requires advanced dielectric functionalities including high capacitance density, high energy density, high current handling capability, high voltage, high temperature, high thermal conductivity, light weight, and environmental reliability. Nanodielectric engineering emerges and attracts extensive efforts from many countries as a result. Unlike prior reviews focusing on lab scale nanocomposite study, this review focuses on recent innovations in polymerbased nanodielectric design on a large scale and their film scale-up efforts for advanced capacitors. The unconventional polymer-nanofiller engineering and their process in the last two decades are discussed. The nanofunctionalized polymers on a molecular level for high dielectric constants and high dielectric strength are briefly described. The challenge associated with film scale-up and retention of nanodielectric properties are then pointed out to be crucial toward a transfer of dielectric and capacitor technology. Several important attempts at scaling up dielectric films and capacitors recently supported by the US government and industry are reviewed. An alternative strategic approach to achieving high performance polymer films is introduced by leveraging 2D surface coating on commercially mature large-scale polymer films. Future pathways for high quality scalable dielectric films exhibiting desirable dielectric properties and feasibility for capacitor manufacturing are suggested.to develop a more compact pulse-forming network for a pulsed high power microwave (HPM), a laser source, aircraft ignition systems, and high-power electrical systems. [1] The US NAVY strove to develop an all-electric warship for advancing its future combat capability (lethality and survivability). This warship required high-power weapons such as electromagnetic railguns for obtaining pin-point accuracy at a very long range electromagnetic launch systems for rapid aircraft and missile deployment and higher-power radar and sonar systems for "seeing" farther through both air and water. The US Army funded the development of the high-energy-density biaxially oriented polypropylene (BOPP) capacitor and the high-temperature polyetherimide dielectric for ground vehicles to realize better serviceability, higher power, and lower mass of the equipment that ground troops carry. [2,3] Although the energy density has been improved up to 3 J cm −3 via metallization control, the performance, and lifetime of BOPP capacitors degrade rapidly with increasing temperature (the ripple current handing capability decreases as the temperature increases from 85 to 105 °C).Improvements in the fault resistance and the reliability of dielectric materials will enable capacitors to withstand higher electrical current and heat without being excessively derated under extreme stress conditions. A large gap remains between the technology availability and the desired properties, such as combined high temperature and energy density and a low dissipation factor. Fa...

Polymer/molecular semiconductor all-organic composites for high-temperature dielectric energy storage

“…Moreover, the insulating nanostructures [14][15][16][17] are synthesized in low yields (e.g., nanosheets and nanowires), have high surface energies (i.e., unsatisfactory compatibility with polymers), and are loaded at high concentrations (c.a. 10 vol.%), rendering the manufacture of largearea and uniform nanocomposite films challenging 19 .…”

Self‐Healing of Electrical Damage in Polymers

“…Because of the complex breakdown mechanism of dielectric polymers such as electronic breakdown and thermal breakdown, the theoretical E b is usually 10 times higher than experimental values of breakdown strength [120] and the (E b /10) values of typical insulating self-healing materials and conventional dielectric polymers are listed in Table 2 for comparison. [4,31,121,108,109,[122][123][124][125][126][127] For thin film dielectric polymers, stringent dielectric and thermal performance requirements in high-field and hightemperature applications leave limited material options. As shown in Table 2, except for some hydrogen bonding networks, the estimated breakdown strengths of most noncovalent intrinsic self-healing materials are much lower than those of the conventional dielectric polymers.…”

Interface modulation in multi-layered BaTiO3 nanofibers/PVDF using the PVP linker layer as an adhesive for high energy density capacitor applications

“…These capacitors find applications in numerous fields such as electronic circuits (filters/ rectifiers, coupling/decoupling, tuning, timing, and bypass), power electronics (commutation and snubbers), pulsed power applications (weapons: military, marine, aerospace, and explosives), medical devices, lighting (fluorescent lamps and discharge lamps) and automotive industries. 3,4 The commercially available biaxially oriented polypropylene (BOPP) capacitor showed a high breakdown strength of B6400 kV cm À1 , but it suffers from a low dielectric constant and hence low energy density (1-1.2 J cm À3 ). 5 Thus, there is an urgent need to develop low-cost and highly efficient dielectric capacitors to meet the next-generation energy requirements.…”