Biomechanical Energy‐Driven Hybridized Generator as a Universal Portable Power Source for Smart/Wearable Electronics

Abstract

The fast growth of smart electronics requires novel solutions to power them sustainably. Portable power sources capable of harvesting biomechanical energy are a promising modern approach to reduce battery dependency. Herein, a novel elastic impact‐based nonresonant hybridized generator (EINR‐HG) is reported to effectively harvest biomechanical energy from diverse human activities outdoors. Through the rational integration of a nonlinear electromagnetic generator with two contact‐mode triboelectric nanogenerators, the proposed EINR‐HG generates hybrid electrical output simultaneously under the same mechanical excitations. By introducing a flux‐concentrator with a nanowire‐nanofiber surface modification, significant improvement in the energy harvesting efficiency of the EINR‐HG is achieved. After optimizing using simulations and vibration tests, the as‐fabricated EINR‐HG delivers an outstanding normalized power density of 3.13 mW cm−3 g−2 across a matching resistance of 1.5 kΩ at 6 Hz under 1 g acceleration. Under human motion testing, the EINR‐HG generates an optimal output power of 131.4 mW with horizontal handshaking. With a customized power management circuit, the EINR‐HG serves as a universal power source that successfully drives commercial smart electronics, including smart bands and smartphones. This work shows the massive potential of biomechanical energy‐driven hybridized generators for powering personal electronics and portable healthcare monitoring devices.

Progress inTENGtechnology—A journey from energy harvesting to nanoenergy and nanosystem

“…Reproduced with permission. Copyright 2020, Wiley-VCH 270 charges available in a material. This intrinsic limiting factor forced researchers into countless directions to push back the limit of power generation using triboelectricity.…”

“…Besides using the sliding mode of TENG, Figure 10D shows a cubic structure designed for the water wave with the utilization of freestanding contact mode of TENG aiming at more effective energy transmission 269 . Except for wind energy and ocean energy, a non‐resonant hybridized generator based on elastic impact in Figure 10E was proposed to harvest mechanical vibration energy sources in the ambient environment 270 . With the non‐resonant structure, the output power can become more stable and less influenced by the limitations of real‐world vibration, such as random and large frequency variation range.…”

Flourishing energy harvesters for future body sensor network: from single to multiple energy sources

“…Therefore, hybridized wearable EHs with the combination of multiple energy conversion mechanisms, including TENG, PENG, and EMG, have been put forward for harvesting mechanical energy, which can leverage the advantages of each mechanism's characteristics and as a complementary part for each other (Tang et al, 2021;Wang et al, 2021;Zhu et al, 2021). For non-flexible wearable EHs, EMG is generally integrated for its high output current compared with PENG and TENG (Toyabur Rahman et al, 2020;Zhang et al, 2019c). Figure 4A shows a rotational pendulum-based hybrid energy generator with a combination of electromagnetic and triboelectric effects (Hou et al, 2019).…”

“…EMGs based on Faraday's law are able to induce large electric current with a varying magnetic field in a conductor coil due to the relative motion between the magnet and the coil. Such non-flexible hybridized designs include watches ( Hou et al., 2019 ), bracelets ( Maharjan et al., 2018 ), insoles ( Jiang et al., 2020a ), and accessories on other wearable devices like bags and clothes ( Rahman et al., 2020 ). However, due to the existence of normally bulked and stiff magnets and non-durable and hardly deformable coils, EMGs are more difficult to be utilized in flexible devices compared with TENGs and PENGs ( Wan et al., 2020 ).…”

Triboelectric Nanogenerators and Hybridized Systems for Enabling Next-Generation IoT Applications

“…Except for the mechanical energy contained among water wave and wind in nature, the vibration generated by machinery and human activities, e.g., suspension systems in vehicles and human walking, can also be harvested for specific applications to avoid energy waste [ 108 – 113 ]. A broadband TENG-PENG hybrid nanogenerator with a bistable structure was developed by Deng et al for ultralow-frequency rectilinear vibration as illustrated in Figure 3(g) [ 114 ].…”