Deep Insight into the Influences of the Intrinsic Properties of Dielectric Elastomer on the Energy-Harvesting Performance of the Dielectric Elastomer Generator

Abstract

The dielectric elastomer (DE) generator (DEG), which can convert mechanical energy to electrical energy, has attracted considerable attention in the last decade. Currently, the energy-harvesting performances of the DEG still require improvement. One major reason is that the mechanical and electrical properties of DE materials are not well coordinated. To provide guidance for producing high-performance DE materials for the DEG, the relationship between the intrinsic properties of DE materials and the energy-harvesting performances of the DEG must be revealed. In this study, a simplified but validated electromechanical model based on an actual circuit is developed to study the relationship between the intrinsic properties of DE materials and the energy-harvesting performance. Experimental verification of the model is performed, and the results indicate the validity of the proposed model, which can well predict the energy-harvesting performances. The influences of six intrinsic properties of DE materials on energy-harvesting performances is systematically studied. The results indicate that a high breakdown field strength, low conductivity and high elasticity of DE materials are the prerequisites for obtaining high energy density and conversion efficiency. DE materials with high elongation at break, high permittivity and moderate modulus can further improve the energy density and conversion efficiency of the DEG. The ratio of permittivity and the modulus of the DE should be tailored to be moderate to optimize conversion efficiency (η) of the DEG because using DE with high permittivity but extremely low modulus may lead to a reduction in η due to the occurrence of premature “loss of tension”.

Largely improved generating energy density, efficiency, and fatigue life of DEG by designing TiO2/LNBR/SiR DE composites with a self-assembled structure

“…4 and Table S2,† because the charging of DEG is a direct-current process. 20 The dielectric constant ( ε r ) of both LNBR/SiR blends and TiO 2 /LNBR/SiR composites decreases with the increase of frequency until reaching a constant value, which is ascribed to the strong dipole polarizability from the CN polar groups of LNBR. From Fig.…”

“…And the PCE of the 10T/SiR composite is lower than that of pure SiR, which is due to its lower DE and higher W mech caused by higher elastic modulus. 20 Because of the increase in DE and the decrease in W mech caused by lower elastic modulus, the PCE of LNBR/SiR blends and TiO 2 /LNBR/SiR composites is higher than that of pure SiR and 10T/SiR. Under the same content of LNBR, the PCE of TiO 2 /LNBR/SiR composites is much higher than that of LNBR/SiR blends because of the higher DE.…”

“…First, although grafting polar dipole groups onto SiR chains by chemical modification can largely improve the ε r of SiR, it can also lead to a significant increase in electrical conductivity, 19 and thus an increase in leakage current, which can lead to a large decrease in Δ E . 20 In addition, the grafting of polar dipole groups onto SiR chains can also lead to a decrease in elongation at break because of the significant decrease in molecular weight of SiR, 21 which can lead to a decrease in tensile strain that can be applied during the energy harvesting process, and thus a decrease in Δ E and w of DEG. The ε r of SiR can also be significantly increased by filling a small amount of conductive filler, but it also leads to a dramatic increase in electrical conductivity and significant decrease in E b .…”

Largely Enhanced Energy Harvesting Performance of Silicone-Based Dielectric Elastomer Generators through Controlling the Uniaxial Device Structure

“…Based on the harvesting cycle for measuring the generated energy of DEG and considering the inevitable charge loss (Q leak ) during the actual harvesting process, the released state D (λ 0 = 1.25) and the theoretical output voltage (V 2 ) are replaced by D′ and V 2 ′ (measured by the oscilloscope, TBS-1202C) respectively, which represent the actual state and the actual output voltage of the DE film. 26 According to the principle of charge conservation throughout the entire energy harvesting process, which can be described as…”

A supramolecular electrode with high self-healing efficiency at room temperature, recyclability and durability for dielectric elastomer generators

“…[1][2][3] In the eld of energy conversion, there is widespread interest in the dielectric elastomer transducer (DET), in which a thin dielectric elastomer (DE) lm is sandwiched between two exible electrodes, allowing the interconversion between mechanical energy and electrical energy under specic conditions, and therefore nding applications in articial muscles, micro-robots, sensors, energy harvesters, etc. [4][5][6][7][8][9] One of its most promising applications is the dielectric elastomer generator (DEG), [10][11][12][13] a kind of deformable elastic capacitor that can easily harvest electrical energy from natural mechanical energy such as human movements, waves, and tides with the help of stretching and energy storage devices. 14,15 Compared with traditional generators of large size and complex structures, the DEG has the advantages of light weight, high energy density and electromechanical conversion efficiency, exible structure, etc.…”