Comparison of Power Density of Triboelectric Generators via Frequency-up-Conversion Method

Abstract In this paper, we experimentally compared the instantaneous volume power density and the average volume power density of the triboelectric nanogenerator (TENG) with and without a frequency-up conversion mechanism. We first proposed a double-cantilever structure TENG (DC-TENG). A conventional contact-separation TENG was also constructed as the control case for electric output comparison. A few experiments were then conducted to investigate how the cantilever’s high-frequency vibrations influence the output voltage, instantaneous power, etc., before those of the triboelectric nanogenerator without frequency conversion. The results indicate that the double-cantilever system effectively converts low-frequency linear impact into high-frequency vibration. As of the best contrast, the DC-TENG yields a maximal open-circuit voltage of 141.5 V, an instantaneous power of 0.76 mW, and an average power of 0.77 μW excited by a linear impact, which frequency is 0.6 Hz and amplitude is 8 mm. The peak and the average power density of generators with the frequency convert device are enhanced by 34 times and 13 times as high as those of the original case, respectively. This finding proves that the cantilever integrated with triboelectric nanogenerators is an effective configuration with evident performance improvement.