Biomechanical Energy Harvesting Research Articles

Healthcare management applications based on triboelectric nanogenerators

In the current era of busy and eventful daily routines, the need for self-driven, robust, and low maintenance healthcare systems emerges significantly more than in earlier times. The nanogenerator (NG) technology provides a new pathway by utilizing nanostructured and eco-friendly materials toward biomedical systems by harvesting biomechanical energy. Triboelectric NGs (TENGs) have been well-developed to cater all these matters, giving self-powered, sustainable, environment-friendly, and low footprint devices. TENG comes up with great potential, therefore, we have summarized various dimensions of its applications in healthcare management, including prevention, detection, diagnosis, and treatment. We have reviewed different aspects of TENG healthcare systems that provide wearable, minimally invasive, and simple solutions while harvesting human motion as the power source. Here, recent advancements of triboelectric devices are compiled while discussing their significance, structure, capabilities, performance, and future potential. Meanwhile, the impact of TENG on protecting and treating various internal and external human organs, such as the heart, neural tissues, skin, and hair, has been described in detail. Moreover, TENG-based solutions have also included minimizing the effects of contemporary and lingering challenges such as air pollution and viral infectious diseases on human health. In the very end, we have concluded with the opportunities and possible solutions for anticipated challenges.

A high-performance textile-based triboelectric nanogenerator manufactured by a novel brush method for self-powered human motion pattern detector

Textile-based triboelectric nanogenerator (t-TENG) has attracted widespread attention because it is the most promising technology in the fields of intelligent electronic textiles and biosensors. However, it is still a challenge for t-TENG with high performance and low cost. Herein, we develop a high-performance t-TENG to harvest biomechanical energy from human motions, in which nanopatterned polydimethylsiloxane (PDMS) – carbon nanotubes (CNTs) film is coated through a novel brush coating method (PCN-TENG). The open-circuit voltage (VOC) and short-circuit current (ISC) can reach 51.2 V and 3.0 μA, respectively, while the traditional dip-coat method only reaches 14 V and 0.82 μA. Furthermore, the self-powered human motion pattern detector (HMPD) is made, which can collect the energy of human movement and identify the movement status (including: walking, running, and jumping) by inserting PCN-TENG into a pair of insoles insole. HMPD has two working modes, in which mode 1 (the single-electrode mode) is good at recognizing movement mode and mode 2 (vertical contact-separation mode) is more advantageous in collecting movement energy of the human body. In this work, high-performance intelligent electronic textiles were prepared by a novel efficient and convenient method and apply them to t-TENG, which had a high potential for future smart clothing products and self-powered biosensors, and a novel self-powered HMPD had been designed to realize human movement monitoring while collecting energy.

Sample-efficient gear-ratio optimization for biomechanical energy harvester

The biomechanical energy harvester is expected to harvest the electric energies from human motions. A tradeoff between harvesting energy and keeping the user’s natural movements should be balanced via optimization techniques. In previous studies, the hardware itself has been specialized in advance for a single task like walking with constant speed on a flat. A key ingredient is Continuous Variable Transmission (CVT) to extend it applicable for multiple tasks. CVT could continuously adjust its gear ratio to balance the tradeoff for each task; however, such gear-ratio optimization problem remains open yet since its optimal solution may depend on the user, motion, and environment. Therefore, this paper focuses on a framework for data-driven optimization of a gear ratio in a CVT-equipped biomechanical energy harvester. Since the data collection requires a heavy burden on the user, we have to optimize the gear ratio for each task in the shortest possible time. To this end, our framework is designed sample-efficiently based on the fact that the user encounters multiple tasks, which are with similarities with each other. Specifically, our framework employs multi-task Bayesian optimization to reuse the optimization results of the similar tasks previously optimized by finding their similarities. Through experiments, we confirmed that, for each task, the proposed framework could achieve the optimal gear ratio of around 50 % faster than one by random search, and that takes only around 20 min. Experimental results also suggested that the optimization can be accelerated by actively exploiting similarities with previously optimized tasks.

Hierarchical Honeycomb-Structured Electret/Triboelectric Nanogenerator for Biomechanical and Morphing Wing Energy Harvesting

HighlightsCreate a hierarchical honeycomb-inspired triboelectric nanogenerator (TENG) with excellent transparency, compactness, lightweight and deformability.Amplify capacitance variation by dividing large hollow space into numerous energy generation units with porous honeycomb architecture.Demonstrate self-powered insole plantar pressure mapping applications by the self-sustained elastic nature of the h-TENG device.Integrate the h-TENG into the morphing wing of small-unmanned aerial vehicles for converting flapping motions into electricity for the first time.

KNN based piezo-triboelectric lead-free hybrid energy films

In recent times, the triboelectric and piezoelectric effects have garnered significant attention towards developing advanced material composites for energy harvesting and sensory applications. In this work, potassium sodium niobate (KNN) based energy films (EF) have been developed to utilize mechanical energy while simultaneously taking advantage of triboelectric and piezoelectric mechanisms. The KNN particles were synthesized using a wet ball milling technique and then incorporated into a polyvinylidene difluoride (PVDF) matrix together with addition of multi wall carbon nanotubes (MWCNT). The film was used to develop a piezoelectric nanogenerator (PENG) fitted with copper electrodes. The piezoelectric output of the film was further tested utilizing copper electrodes, at variable tapping frequency (60 BPM to 240 BPM) and pressure (10–40 psig) were used when activating the pneumatic piston. The open circuit voltage increased with the increase of both tapping frequency and pressure. The maximum piezoelectric output voltage was observed to be 35.3 V while the maximum current was noted as 15.8 µA. The films also showed unique output signals for different types of deformations performed under hand pressure. The film was further utilized to build a piezo-triboelectric hybrid nanogenerator to check its hybrid performance. The maximum output was observed to be 54.1 V and 29.4 µA. This film was integrated with conventional electronic components (bridge rectifiers, resistors, and capacitors) and tested for its ability to harvest energy. The hybrid nanogenerator can charge a 0.1 µF capacitor to 9.4 V in 60 s. The optimum output power for the device was measured to be 0.164 W. The film was further attached with a Kapton film and showed a hybrid output of 113.2 V. This experiment endorsed the potential of the KNN based energy films for multifunctional applications like force, pressure, and motion sensing as well as lead free energy harvesting. Potassium sodium niobate (KNN) was synthesized and incorporated into PVDF along with MWCNT to produce lead-free piezoelectric and piezo-triboelectric hybrid energy films. The high piezoelectric and piezo-tribo hybrid output response showed its potential in biomechanical energy harvesting. Besides, the energy film can be utilized for biomechanical motion and pressure sensing operations. • KNN/PVDF/MWCNT based lead-free energy film was synthesized for piezoelectric and triboelectric operation. • The energy film was tested at variable pressure, load frequency, and finger motions. • The hybrid energy film showed high output of 54.1 V and 29.4 μA. • The energy film can be used for powering small electronic devices and multidimensional sensory operations.

Biomechanical Energy Harvester: Skin‐like Elastomer Embedded Zinc Oxide Nanoarrays for Biomechanical Energy Harvesting (Adv. Mater. Interfaces 10/2021)

An ultra-flexible and stretchable biomechanical energy harvester is developed by Zi Chen, Marc D. Feldman, John X. J. Zhang and co-workers as described in article number 2100094. The ZnO nanorod array is sandwiched by a layer of electrode (carbon nanotube) and biocompatible polymer PDMS. Piezoelectricity of ZnO will generate electricity across the two electrodes in response to mechanical deformation.

Imperceptible energy harvesting device and biomedical sensor based on ultraflexible ferroelectric transducers and organic diodes

Energy autonomy and conformability are essential elements in the next generation of wearable and flexible electronics for healthcare, robotics and cyber-physical systems. This study presents ferroelectric polymer transducers and organic diodes for imperceptible sensing and energy harvesting systems, which are integrated on ultrathin (1-µm) substrates, thus imparting them with excellent flexibility. Simulations show that the sensitivity of ultraflexible ferroelectric polymer transducers is strongly enhanced by using an ultrathin substrate, which allows the mounting on 3D-shaped objects and the stacking in multiple layers. Indeed, ultraflexible ferroelectric polymer transducers have improved sensitivity to strain and pressure, fast response and excellent mechanical stability, thus forming imperceptible wireless e-health patches for precise pulse and blood pressure monitoring. For harvesting biomechanical energy, the transducers are combined with rectifiers based on ultraflexible organic diodes thus comprising an imperceptible, 2.5-µm thin, energy harvesting device with an excellent peak power density of 3 mW·cm−3.

Flexible and stretchable triboelectric nanogenerator fabric for biomechanical energy harvesting and self-powered dual-mode human motion monitoring

Simultaneous monitoring of human motion and collecting ambient energy are important for the development of personal healthcare monitoring and artificial intelligence. Here, a flexible and stretchable coaxial triboelectric nanogenerator (TENG) yarn is designed and fabricated by using coil spring as the inner support layer and mechanoluminescent ZnS:Cu/PDMS composite as the outer friction layer. By weaving coaxial TENG yarns, or mix-weaving with other yarns, a multifunctional TENG fabric can be manufactured for energy harvesting external mechanical energy from human motion or ambient environment. More important, it can self-powered sense human motion in both electrical (through TENG) and optical (from mechanoluminescent ZnS:Cu/PDMS composite) methods. This work provides a new strategy for wearable TENG fabrics with dual-mode sensing and energy harvesting which have potential applications in long-term medical monitoring and human-machine interaction systems. A multifunctional triboelectric nanogenerator fabric is manufactured for energy harvesting external mechanical energy from human motion or ambient environment. Moreover, on the basis of coupling effects between the mechanical luminescence and triboelectrification important, it can self-powered sense human motion in both electrical (through TENG) and optical (from mechanoluminescent ZnS: Cu/PDMS composite) methods. • The wearable fiber is fabricated for energy harvesting and monitoring human signals in medical rehabilitation. • A dual-mode strain sensor is designed by triboelectricity and mechanoluminescence. • A fiber-shaped sensor possesses mechanical luminescence performance, which can sense the force variation more intuitively. • The triboelectric fiber exhibit good washing resistance and reusability.

Nonlinear multi-mode electromagnetic insole energy harvester for human-powered body monitoring sensors: Design, modeling, and characterization

The current research in wearable electronics is trending towards miniaturization, portability, integration, and sustainability, with the harvesting of biomechanical energy seen as a promising route to improve the sustainability of these wearable electronics. Efforts have been made to prolong operational life of these harvesters, to overcome energy dissipation, lowering resonant frequency, attaining multi-resonant states as well as widening frequency bandwidth of these biomechanical energy harvesters. Herein, an electromagnetic insole energy harvester (EMIEH), capable of efficiently harvesting low-frequency biomechanical energy, has been designed, fabricated and experimentally tested. The core component in the device is the vibrating circular spiral spring, holding two magnets as the driving force on the central platform of the circular spiral spring, and just in-line with the upper and lower wound coils. It has been shown that the harvester exhibits higher sensitivity to low-frequency external vibrations than conventional cantilever-based designs, and hence allows low impact energy harvesting such as harvesting energy from walking, running and jogging. The experimentally-tested four resonant frequencies occurred at 8.9 Hz, 28 Hz, 50 Hz, and 51 Hz. At the first resonant frequency of 8.9 Hz under base acceleration of 0.6 g, the lower electromagnetic generator can deliver a peak power of 664.36 µW and an RMS voltage of 170 mV to a matching load resistance of 43.5 Ω. The upper electromagnetic generator can contribute an RMS voltage of 85 mV, corresponding to the peak power of 175 µW across 41 Ω under the same experimental condition. Finally, the harvester has been integrated into the shoe and it is able to charge a 100 µF capacitor up to 1 Volt for about 8 minutes foot movement. The result has remarkable significance in the development of wireless body monitoring sensors applications.

A Stretchable, Self-Healable Triboelectric Nanogenerator as Electronic Skin for Energy Harvesting and Tactile Sensing.

Electronic skin that is deformable, self-healable, and self-powered has high competitiveness for next-generation energy/sense/robotic applications. Herein, we fabricated a stretchable, self-healable triboelectric nanogenerator (SH-TENG) as electronic skin for energy harvesting and tactile sensing. The elongation of SH-TENG can achieve 800% (uniaxial strain) and the SH-TENG can self-heal within 2.5 min. The SH-TENG is based on the single-electrode mode, which is constructed from ion hydrogels with an area of 2 cm × 3 cm, the output of short-circuit transferred charge (Qsc), open-circuit voltage (Voc), and short-circuit current (Isc) reaches ~6 nC, ~22 V, and ~400 nA, and the corresponding output power density is ~2.9 μW × cm−2 when the matching resistance was ~140 MΩ. As a biomechanical energy harvesting device, the SH-TENG also can drive red light-emitting diodes (LEDs) bulbs. Meanwhile, SH-TENG has shown good sensitivity to low-frequency human touch and can be used as an artificial electronic skin for touch/pressure sensing. This work provides a suitable candidate for the material selection of the hydrogel-based self-powered electronic skin.

Applying a triboelectric nanogenerator by using facial mask for flexible touch sensor

With the development of artificial intelligence, research on the touch sensor has become a popular object. Here, we proposed a novel triboelectric nanogenerator based on the facial mask (FM-TENG) for harvesting mechanical energy, and it can also serve as a flexible touch sensor. A series of triboelectricity experiments show that facial mask has a strong ability to lose electrons. The FM-TENG can generate good performance, as evidenced by peak short-circuit current (Isc), open-circuit voltage (Voc), and power density values of 37.48 μA, 1037 V, and 727.78 μW/cm2, respectively. Commercial electronics, including an electronic calculator, and a total of 150 high-power light-emitting diodes (LEDs), were easily driven by the FM-TENG. Additionally, the facial mask is harmless material for human skin, and thus it is smeared on the skin to form a self-powered flexible touch sensor to distinguish the different states of fingers. As a new-efficient method for developing low-cost bio-mechanical energy harvesters and self-powered touch sensors, we also foresee that an alert touch sensing system represents tremendous progress in the smart wireless sensor networks.

A fluorinated polymer sponge with superhydrophobicity for high-performance biomechanical energy harvesting

Human body contains various biomechanical energy, which emerges as a pervasive and sustainable energy resource for wearable electronics in the era of Internet of Things. We have developed a fluorinated polymer sponge based triboelectric nanogenerator (FPS-TENG) that provides stable electrical output over a wide range of ambient humidity. The humidity resistance due to excellent hydrophobic property of the fluorinated polymer sponge can overcome the adverse effects of moisture. The FPS-TENG also exhibits high durability even after enduring heavy abrasion. The output voltage of the FPS-TENG is three times higher than that of the pristine polymer film (PPF) based TENG. When assembled with hydrophobic copper (HC) contact electrodes, the FPS-TENG retains almost 90% electrical output over 20–85% relative humidity. Moreover, super durability is achieved by quasi-bulk-phase functionalization. After 1 mm-thickness abrasion of the fluorinated polymer sponge, the output voltage is degraded by only 10%. Under the optimal operating conditions, the FPS-TENG delivers a maximum power density of 0.89 W m −2 at a load resistance of 10 MΩ. The fluorination enhanced triboelectrification and the surface superhydrophobicity induced humidity-stability make the FPS-TENG a sustainable power source for the wearable bioelectronics in the era of Internet of Things. • Moisture-resistant triboelectric nanogenerator was developed. • Fluorination treatment effectively improves hydrophobicity. • Quasi-bulk-phase functionalization enables super durability. • Parametric experimental results yield optimal material design.

Polarization- and Electrode-Optimized Polyvinylidene Fluoride Films for Harsh Environmental Piezoelectric Nanogenerator Applications.

While piezoelectric nanogenerators have demonstrated the effective conversion of tiny mechanical vibrations to electricity, their performances are rarely examined under harsh environmental conditions. Here, amultilayered polyvinylidene fluoride (PVDF) film-based piezoelectric nanogenerator (ML-PENG) is demonstrated to generate considerable and stable power outputs even at extremely low temperatures and pressures, and under strong UV. Up-/down-polarized PVDF films are alternately stacked, and Ag electrodes are intercalated between the two adjacent films. At -266°C and 10-5 Torr, the ML-PENG generates an open-circuit voltage of 1.1V, a short-circuit current density of 8nAcm-2 , and a power density of 4.4nWcm-2 . The piezoelectric outputs are quite stable against prolonged illumination of UV, large temperature- and pressure-variations, and excessive mechanical vibrations. The piezoelectric power density is greatly enhanced above the freezing and glass transition temperatures of PVDF and recorded to be 10, 105, and 282nWcm-2 at -73, 0, and 77°C, respectively. The ML-PENG generates sufficient power to operate five light-emitting diodes by harvesting biomechanical energy under simulated Martian conditions. This work suggests that polarization- and electrode-optimized ML-PENG can serve as a reliable and economic power source in harsh and inaccessible environments like polar areas of Earth and extraterrestrial Mars.

Self‐Powered Drug‐Delivery Systems Based on Triboelectric Nanogenerator

Triboelectric nanogenerator (TENG) can convert mechanical energy into electricity via the coupling of triboelectrification and electrostatic induction. Due to its advantages of flexible, lightweight, high‐energy conversion efficiency and shape‐adaptive ability, implantable and wearable TENG have shown great potentials in biomedical field for biomechanical energy harvesting, biosensing, and therapy. In this Perspective, recent advances of TENG for self‐powered drug delivery, mainly including controlled drug release as well as drug delivery based on electroporation and iontophoresis are systematically overviewed. Also the significance of self‐powered drug‐delivery system in personalized healthcare is emphasized, and conclude with the open challenges and future perspectives of TENG‐based drug‐delivery systems.

Towards Bio-Hybrid Energy Harvesting in the Real-World: Pushing the Boundaries of Technologies and Strategies Using Bio-Electrochemical and Bio-Mechanical Processes

Sustainable, green energy harvesting has gained a considerable amount of attention over the last few decades and within its vast field of resources, bio-energy harvesters have become promising. These bio-energy harvesters appear in a wide variety and function either by directly generating energy with mechanisms similar to living organisms or indirectly by extracting energy from living organisms. Presently this new generation of energy harvesters is fueling various low-power electronic devices while being extensively researched for large-scale applications. In this review we concentrate on recent progresses of the three promising bio-energy harvesters: microbial fuel cells, enzyme-based fuel cells and biomechanical energy harvesters. All three of these technologies are already extensively being used in small-scale applications. While microbial fuel cells hold immense potential in industrial-scale energy production, both enzyme-based fuel cells and biomechanical energy harvesters show promises of becoming independent and natural power sources for wearable and implantable devices for many living organisms including humans. Herein, we summarize the basic principles of these bio-energy harvesting technologies, outline their recent advancements and estimate the near future research trends.

P–N junction-based ZnO wearable textile nanogenerator for biomechanical energy harvesting

Abstract Wearable nanogenerators have attracted intensive interest owing to their ability to convert the energy from body movement and the surrounding environment to electronic signals, which can power portable/wearable electronic devices for sensing, motion tracking or monitoring to improve the quality of human life. Herein, a p-n junction ZnO textile nanogenerator is successfully fabricated on conductive textiles utilising PEDOT:PSS/CuSCN-coated ZnO nanorods, combining the advantage of ZnO piezoelectricity and textile flexibility. It is found that by increasing the length of ZnO nanorods, the nanogenerators exhibit increasing output voltage and power density. The device with optimized ZnO nanorods length produces increasing output voltage from 0.2 V to 1.81 V as the shaking frequency increases from 19 Hz to 26 Hz, which can activate an LCD screen display. In addition, the device is able to generate increasing negative voltage from 1.64 V to 5.08 V by an increasing impacting force. Other mechanical forces such as flicking, gentle finger bending and tapping can also be harvested by the fabricated device. These results are of particular importance in designing future flexible self-powered devices and wearable electronics.

Soft triboelectric nanogenerators for mechanical energy scavenging and self-powered sensors

Abstract Efficient scavenging and converting energy from surrounding environment to achieve the self-powered operation of electronics has attracted tremendous interest to meet the energy needs of the rapidly growing Internet of Things and portable devices. As a promising technology, the triboelectric nanogenerator (TENG) possesses the capability of efficient utilization of ambient mechanical energy for energy supply and self-powered sensing. By integrating the soft materials into TENG, the soft TENG can be triggered by a quite weak external mechanical stimulation and realize a better conversion of micro mechanical energy. Meanwhile, the deformable soft TENGs further expand the application scenarios of TENGs. Here, the advances of soft TENGs by focusing on the fundamentals, candidate materials, promising structures, applications in energy scavenging and self-powered sensors are reviewed. In particular, the wearable and implantable soft TENGs, through which the related self-powered sensing or biomechanical energy harvesting can be realized in vivo and in vitro respectively, are summarized. Finally, the unique advantages and possible focuses for scientists in future of soft TENGs are emphasized.

Enhancing output performance of triboelectric nanogenerator via large polarization difference effect

Abstract The utilization of inorganic ferroelectric ceramics is thought to be an effective approach to enhance output performances of triboelectric nanogenerators (TENGs). However, the large remnant polarization from ferroelectric ceramics traps partial charges on electrodes all the time, which limits the performance improvement of TENGs and their applications in energy harvesting and self-powered sensing. Herein, achieving absolute exploitation of dielectric polarization from inorganic ceramics for significant performance enhancement is unprecedentedly proposed by using antiferroelectric ceramics with large polarization difference. The features of nearly zero remnant polarization and large maximum polarization for antiferroelectric ceramics perfectly match the working cycle mechanism of TENGs, enabling all polarization induced charges to flow through the external circuit. Based on this concept, an ideal flexible Pb0.94La0.04Zr0.98Ti0.02O3 (PLZT) antiferroelectric ceramic inner-layer with record-high polarization difference is developed and assembled into a triboelectric nanogenerator (PLZT-TENG). The PLZT-TENG exhibits an outstanding output of 13.5 nC cm–2, a 1.6-fold enhancement compared with the TENG with a PbZr0.52Ti0.48O3 (PZT) ferroelectric ceramic inner-layer. Thanks to excellent flexibility, stability, and durability, the PLZT-TENG can serve as a biomechanical energy harvester and a self-powered sensor to be applied in practice. Our findings open a generic and upgradable way to the evolution and optimization of TENGs.

Organogel electrode based continuous fiber with large-scale production for stretchable triboelectric nanogenerator textiles

Wearable electronics had drawn great attentions in recent years because of their valuable applications in our daily lives. Among them, triboelectric nanogenerator (TENG) textile was a promising candidate to alleviate electricity supply problem of wearable electronics. However, currently used electrodes in TENG textile are hard to fulfill the requirements of stretchable electronics. Here, organogel conductor was proposed as electrode to construct triboelectric fiber (GS-fiber), owing to its merits of flexibility, stretchability and conductivity. The core/shell structure GS-fiber was prepared from gel’s photo-crosslinking in transparent silicone hollow fiber, in which hollow fiber was the mold for gel electrode and outer friction layer. The flexibility and solid form of organogel electrode avoided the cracking problem of metallic electrode and leakage problem of liquid electrode in TENG textile, which make GS-fiber a stretchable and tailorable fiber. Moreover, the facile preparation process endowed GS-fiber with large-scale production ability and 30-meter GS-fiber was prepared for demonstration. The GS-fiber was then knitted into TENG textile (GS-teng) for bio-mechanical energy harvesting. This work indicated that organogel electrode has great potential in triboelectric fiber, which was a remarkable progress towards TENG textiles’ industrial application. Organogel conductors were proposed as electrode to construct a new kind of triboelectric fibers (GS-fiber), owing to organogel conductors’ unique merits of flexibility, conductivity and stretchability. The core/shell structure GS-fiber was prepared from gel’s photo-crosslinking in transparent silicone hollow fiber, in which hollow fiber was the mold for gel electrode and outer friction layer of GS-fiber. The flexibility and solid form of organogel electrode avoided the cracking problem of metallic electrode and leakage problem of liquid electrode in textile based TENG, which makes GS-fiber a stretchable and tailorable fiber in processing. Moreover, the facile preparation process endowed GS-fiber with large-scale production ability and 30-meter GS-fiber was prepared for demonstration. The GS-fiber was then knitted into TENG textile (GS-teng) for bio-mechanical energy harvesting. This work indicated that organogel electrode has great potential in triboelectric fiber, which was a remarkable progress towards industrial application of TENG textiles. • Organogel conductor was applied as electrode fiber with stretchability and conductivity. • The prepared triboelectric fiber (GS-fiber) was continuous fiber for large-scale production. • GS-fiber was stretchable and tailorable, which was suitable for textile processing. • The electrode avoided cracking or leakage of metallic or liquid electrode’s problems.

Power Backpack for Energy Harvesting and Reduced Load Impact.

Long-distance walking with heavy loads is often needed when going hiking or for field rescue, which is prone to cumulative fatigue. There is also a great need for labor-saving and biomechanical energy harvesting in daily life for extended security and communication needs. Here, we report a load-suspended backpack for harvesting the wasted energy of human motion based on a triboelectric nanogenerator (TENG). Two elastomers are incorporated into the backpack to decouple the synchronous movement of the load and the human body, which results in little or no extra accelerative force. With such a design, through theoretical analysis and field experiments, the backpack can realize a reduction of 28.75 % in the vertical oscillation of the load and 21.08 % in the vertical force on the wearer, respectively. Meanwhile, the mechanical-to-electric energy conversion efficiency is modeled and calculated to be 14.02 % under normal walking conditions. The designed backpack has the merits of labor-saving and shock absorption as well as electricity generation, which has the promising potential to be a power source for small-scale wearable and portable electronics, GPS systems, and other self-powered health care sensors.