Self-charging System Research Articles

A H2O2 Self-Charging Zinc Battery with Ultrafast Power Generation and Storage.

Self-charging power systems are considered as promising alternatives for off-grid energy devices to provide sustained electricity supply. However, the conventional self-charging systems are severely restricted by the energy availability and time-consuming charging process as well as insufficient capacity. Herein, we developed an ultrafast H2O2 self-charging aqueous Zn/NaFeFe(CN)6 battery, which simultaneously integrates the H2O2 power generation and energy storage into a battery configuration. In such battery, the chemical energy conversion of H2O2 can generate electrical energy to self-charge the battery to 1.7 V through the redox reaction between H2O2 and NaFeFe(CN)6 cathode. The thermodynamically and kinetically favorable redox reaction contributes to the ultrafast H2O2 self-charging rate and the extremely short self-charging time within 60 seconds. Moreover, the rapid H2O2 power generation can promptly compensate the energy consumption of battery to provide continuous electricity supply. Impressively, this self-charging battery shows excellent scalability of device architecture and can be designed to a H2O2 single-flow battery of 7.06 Ah to extend the long-term energy supply. This work not only provides a route to design self-charging batteries with fast charging rate and high capacity, but also pushes forward the development of self-charging power systems for advanced large-scale energy storage applications.

Compatible interface based self-charging fiber for wearable electronic

With the rapid development of wearable devices, there is an increasing demand for flexible, eco-friendly, and reliable power sources. The self-charging energy system, which integrates energy collection and storage, has emerged as one of the most promising sustainable energy sources, with an urgent need for its application and implementation. In this work, we proposed a fiber-shaped self-charging system based on supercapacitor (SC) and triboelectric nanogenerator (TENG). For the supercapacitor, a silver-decorated carbon fiber with PEDOT: PSS coated is used as the positive electrode, while carbon nanotube film/Fe2O3/MoS2 serves as the negative electrode. The assembled coaxial structure not only shortens the distance between the positive and negative electrodes, effectively improving charge transfer efficiency, but also ensures the flexibility and mechanical stability of the device. The designed supercapacitor exhibited a capacitance of 213.3 mF cm−2 and demonstrated excellent stability of 92 % retention rate even after 5000 cycles. Moreover, the negative electrode of the supercapacitor also serves as a compatible interface for the TENG, with silicone rubber coating acting as the friction layer, forming a single-electrode structure. This coaxial structure with a compatible interface allows for higher efficiency in charge capture and transfer, doubling the charging efficiency compared to incompatible structures, while also ensuring flexibility, making it more suitable for wearable applications. By weaving the TENG, it exhibits an open-circuit voltage of 150 V, a short-circuit current of 6 μA, and a high power density of 900 mW cm−2. In addition, it can also serve as a self-powered sensor, capable of accurately detecting human motion and current conditions. This research proposes an effective compatible interface architecture promising application prospect for advancing sustainable development of self-powered wearable electronic devices.

Cyclodextrin incorporated textile supercapacitor/piezo-triboelectric nanogenerator hybrid system for versatile temperature dependent wearable wireless devices

The problem of wearable textile electronics having no power source can be greatly assisted at low-temperature environments by the demand for flexible supercapacitor sustaining self-charging system. We explore a typical piezo-triboelectric nanogenerators (PTNGs) textile fabric integrated flexible supercapacitors (SCs) face substantial difficulty in maintaining their ability to quickly charge in colder environments for various wearable wireless sensing devices. PTNGs using composite electrodes frequently experience quick performance degradation at low energy levels as a result of the poor ion mobility besides charge transfer in the electrolyte. In this article, we offer a SC-coupled self-chargeable power generator with wide operating temperature range (25 ∼ −80 °C). A composite system of sulfonated β-cyclodextrin/polyvinylpyrrolidone/Ni@MnCO3 on cotton fabric with polyvinylidene fluoride and polydimethylsiloxane were used to build the smart textile SC, which produced 19.6 V at −80 °C and exhibited a gravimetric capacitance of 94.7 Fg−1 with excellent cyclic stability (>50,000). The biocompatibility studies reveal good results (∼95 % of cell viability) for the wearable textile SCs. In addition, the possibility of application to a sensing device was successfully demonstrated by connecting the proposed self-driving energy storage complex to a device designed as a wireless circuit. This system can work for seamlessly working for wireless signal transmittance as power source resulting and this system may be able to meet the urgent need for wearable electronics that implanted in the space suit and/or winter clothing needed in harsh climates.

Performance enhancement of self-charging system by combining triboelectric nanogenerators and dielectric capacitors

As an emerging platform technology, triboelectric nanogenerator (TENG) provides an effective strategy for the realization and widespread deployment of self-powered wireless sensor nodes. However, TENG still faces challenges that necessitate continuous optimization in terms of device structure and output performance. Here, we propose a novel approach to fabricate an all-in-one self-charging system (A-SCS) by integrating a TENG and a dielectric capacitor made from poly(vinylidene fluoride-co-hexafluoropropylene) (P(VDF-HFP)) membrane using the configuration of shared electrodes. The integration capitalizes on the unique characteristics of each component, leading to an enhanced output performance. A 5.5 cm × 5.5 cm sized A-SCS is capable of generating voltages up to 2800 V, with each cycle storing an impressive energy of approximately 3 μJ, which can achieve self-triggered high voltage pulse output through the utilization of discharge tubes. Furthermore, even when miniaturized to a size of 1 cm × 1 cm, the A-SCS exhibits excellent output performance, with a maximum voltage output of 271 V, which is of significant importance for the integration and miniaturization of the A-SCSs. This work not only provides a feasible strategy to develop a new type of high-performance A-SCS, but also presents an excellent application prospect for miniaturized TENGs capable of generating high-voltage pulses.

Ion Pre-Embedding Engineering of δ-MnO2 for Chemically Self-Charging Aqueous Zinc Ions Batteries.

Aqueous zinc ion batteries (ZIBs), especially those with self-charging properties, have been promisingly developed in recent years. Yet, most inorganic materials feature high redox potential, which limit their development in the self-charging field. To achieve this target, by pre-embedding potassium ions into δ-MnO2 to reduce the energy barrier in oxygen adsorption, the first application of MnO2 in self-charging ZIBs is realized. The design features a facile two-electrode configuration with no excessively complex component to allow for energy storage and conversion. Due to the voltage difference between the oxygen in the air and the discharge products, a redox reaction can be carried out spontaneously to realize the self-charging process. After the chemical self-charging process, the Zn-K0.37 MnO2 ·0.54H2 O/C cell achieves an open circuit voltage of around 1.42V and a discharge capacity of 201mAhg-1 , reflecting the promising self-charging capability. Besides, the chemically self-charging ZIBs operate well in multiple modes of constant current charge/discharge/chemical charging. And decent cycling capability can also be achieved at extreme temperatures and high mass loading. This work promotes the development of ZIBs and further broadens the application of inorganic metal oxides in the self-charging systems.

Washable All-in-One Self-Charging Power Unit Based on a Triboelectric Nanogenerator and Supercapacitor for Smart Textiles.

Lightweight, portability, and sustainability have become key factors of the power source for the rapid development of multifunctional wearable electronic devices. In this work, a washable, wearable, and durable self-charging system for human motion energy harvesting and storage based on asymmetric supercapacitors (ASCs) and triboelectric nanogenerators (TENGs) is investigated. The all-solid-state flexible ASC is composed of a cobalt-nickel layered double hydroxide grown on a carbon cloth (CoNi-LDH@CC) as the positive electrode and activated carbon cloth (ACC) as the negative electrode and exhibits the performance of small size, high flexibility, and superior stability. The device was able to provide a capacity of 345 mF cm-2 and a cycle retention rate of 83% after 5000 cycles, which shows great potential as an energy storage unit. Additionally, flexible silicon rubber-coated carbon cloth (CC) is waterproof and soft and can be used as a TENG textile to gain energy for stable charging of an ASC, which presents an open-circuit voltage and short-circuit current of 280 V and 4 μA, respectively. The ASC and TENG can be assembled to continuously collect and store energy, which provides an all-in-one self-charging system qualified with washable and durable for potential applications in wearable electronics.

Electret elastomer-based stretchable triboelectric nanogenerators with autonomously managed power supplies for self-charging systems

Stretchable power sources capable of accommodating large deformations are urgently demanded for various stretchable and wearable electronics. In this work, we report a stretchable electret-based triboelectric nanogenerator (SEB-TENG) consisting of elastomeric electret as electrification materials and organo-hydrogels as electrodes. The electret elastomer, prepared by uniformly dispersing SiO2 nanoparticles in the elastomer matrix and thermally injecting static charges, obtains a high surface potential, high tensile strain (796%), and long stability. Then, the SEB-TENG device also achieves high stretchability (423%) and high charge density (0.2 mC m−2). Furthermore, a power management module (PMM) is designed to maximize the energy utilization of the SEB-TENG. The integrated self-charging system can be sufficiently used to constantly power a watch, or charge a Li-ion coin cell which subsequently provides sustainable power supplies to a digital thermometer. This work provides a viable approach to simultaneously achieve high output performances and high stretchability of integrated power sources.

Hierarchical polypyrrole@cobalt sulfide-based flexible on-chip microsupercapacitors with ultrahigh energy density for self-charging system

Hierarchical polypyrrole@cobalt sulfide-based flexible on-chip microsupercapacitors with ultrahigh energy density for self-charging system

Enhancement of OCV and capacity by activating electrolyte with polyiodide ions towards high-availability self-charging zinc ion batteries

Self-charging zinc ion batteries (ZIBs) without integrated external power generation equipment, featuring simple configuration and strong adaptability, is considered an advanced technology to overcome acute dependence on energy sources and high selectivity on the spatiotemporal environment in the conventional self-charging system. To enable high availability for practical applications, increasing the open-circuit voltage (OCV) and capacity of the self-charging ZIBs is undoubtedly an effective route. In this study, the self-charging mechanism of the VO 2 /ZnSO 4 /Zn (VO 2 /ZS/Zn) battery was revealed as the spontaneous oxidation of discharge product HVO 2 . Accordingly, polyiodide ions were introduced to activate the ZnSO 4 electrolyte to enhance spontaneous oxidation. As a result, the OCV of the self-charging ZIB was increased from 1.15 to over 1.3 V. Further coupling with light stimulation, the self-charging capacity reached 206 mAh g −1 at 0.3 A g −1 , while the self-charging process was shortened from more than 20 h to less than 2 h. The assembled pouch ZIBs displayed a stable capacity (retention: 80%) after 50 self-charging cycles. They can be charged at various modes, such as galvanostatic or/and self-charging in dark or light, demonstrating a powerful ability to harvest and store energy in different external environments. This work provides a facile and effective route to optimize performance for the practical applications of self-charging ZIBs in self-powered systems, clean energy harvest/storage, city power supply, etc.

A Highly integrated flexible photo-rechargeable system based on stable ultrahigh-rate quasi-solid-state zinc-ion micro-batteries and perovskite solar cells

Miniaturized flexible photo-rechargeable systems show bright prospects for wide applications in internet of things, self-powered health monitoring and emergency electronics. However, conventional systems still suffer from complex manufacturing processes, slow photo-charging and discharging rate, and mismatch between photovoltaic and energy storage components in size, mechanics and voltage, etc. Here, we demonstrate a facile inkjet printing and electrodeposition approach for fabricating a highly integrated flexible photo-rechargeable system by combining stable and ultra-high-rate quasi-solid-state Zn-MnO 2 micro-batteries (ZMBs) with flexible perovskite solar cells (FPSCs). In particular, Ni protective layer is first introduced into ZMBs to stabilize battery configuration and facilitate enhanced electrochemical performance. The optimized ZMB exhibits ultrahigh volumetric energy density of 148 mWh cm −3 (16.3 μWh cm −2 ) and power density of 55 W cm −3 (6.1 mW cm −2 ) at the current density of 400 C (5 mA cm −2 ), enabling them comparable with the state-of-the-art micro-batteries or supercapacitors fabricated by conventional methods. The embedded FPSCs show excellent photovoltaic performance, sufficient to charge ZMBs and create a self-charging system capable to offer energy autonomy in miniaturized wearable electronics. The integrated systems can achieve an ultrafast photo-charging within 30 s, with sufficient energy to power other functional electronics (e.g., LED bulb and pressure sensor) for tens of minutes. This prototype offers a promising scheme for next-generation miniaturized flexible photo-rechargeable systems.

Proton Chemistry Induced Long-Cycle Air Self-Charging Aqueous Batteries.

Air self-charging aqueous metal-ion batteries usually suffer from capacity loss after self-charging cycles due to the formation of basic salts on cathodes in the near-neutral electrolytes. Here, air self-charging Pb/pyrene-4,5,9,10-tetraone (PTO) batteries based on proton chemistry are developed in acidic electrolyte. The fast kinetics of H+ uptake/removal endows the battery with enhanced electrochemical performance. Owing to the high standard electrode potential of oxygen in acid electrolyte, the discharged cathodes are spontaneously oxidized by oxygen in air along with H+ extraction and thus achieve self-charging without external power supply. Notably, the air self-charging mechanism involved H+ -based redox can effectively avoid the generation of basic salts on self-charging electrodes and thus guarantee long-term self-charging/galvanostatic discharging cycles of Pb/PTO batteries. This work provides a promising strategy for designing long-cycle air self-charging systems.

Extreme environment-adaptable and fast self-healable eutectogel triboelectric nanogenerator for energy harvesting and self-powered sensing

Hydrogel-based triboelectric nanogenerators (H-TENGs) are emerging as an appealing platform for the wearable electronics owing to their attractive mechanical flexibilities and conductive properties. However, time- and energy-consuming polymerization process of hydrogel and inevitable freezing of water within hydrogel networks at sub-zero temperature severely limit the practical applications of H-TENGs. To address the issues, we herein report a transparent, stretchable, anti-freezing, and self-healable TENG based on the ultrafast fabricated eutectogels for energy harvesting and self-powered sensors. The eutectogel electrode is initially constructed by a dynamic oxidation and coordination system composed of sulfonated lignin (SL) and Fe3+. After immersed in deep eutectic solvent (DES), the obtained eutectogels with high stretchability (~450%), transparency (93.5%) and ionic conductivity (8.70 mS cm−1) can be retained even in extreme temperature as low as − 80 °C. Notably, the eutectogel assembled TENGs (E-TENGs) show high and stable electrical output performances including open-circuit voltage of 105 V, short-circuit current of 0.5 µA, short-circuit charge of 10 nC, and power density up to 53 mW m−2. The E-TENG with a self-charging system can easily light up 20 light-emitting diodes (LEDs) and charge up capacitors to drive commercial electronics by harvesting energy. Moreover, as a proof of concept, the flexible E-TENG can serve as a self-powered biomechanical sensor to realize the real-time monitoring of various human motions, which provide a promising and versatile platform for environment adaptable hydrogel-based TENG with reliable output performance and self-healing ability.

Anti-freezing and stretchable triboelectric nanogenerator based on liquid electrode for biomechanical sensing in extreme environment

The development of intelligent and wearable electronics raises an urgent requirement for stretchable, durable power sources and sensors. Especially, self-powered sensor that can work with high sensing sensitivity and stability in harsh environments is greatly desired for wilderness exploration and urgent rescue. Herein, an anti-freezing, stretch-matched, and liquid electrode-based TENG (Abbr. as AS-TENG) is developed and demonstrated for biomechanical sensing in extremely cold environments. The liquid electrode with the integration of lithium chloride electrolyte, graphene oxide micro-/nano- sheets and ethylene glycol (LiCl/GO/EG) acted as the electrode is encapsulated within a dielectric elastomer as the electrification layer, allowing the resultant single-electrode AS-TENG to achieve a high stretchability of 200% and high electrical performance output with open-circuit voltage of 317 V, short-circuit current of 27 μA, and short-circuit charge of 100 nC. It can be used as a self-powered wearable sensor to be attached on human body for monitoring the biomechanical motion, and can also be used as a power source of a self-charging system to power electronic devices. Most importantly, the AS-TENG can work under severe condition within a wide temperature range (−40 ~ +25 °C) without sacrificing its sensing performance. This work provides a broad application prospect for the development of anti-freezing, stretchable, and liquid electrode-based TENG as wearable sensor under harsh conditions.

Biomimetic self-powered artificial muscle using tri-functional yarns that combine generator, supercapacitor, and actuator functions

Artificial muscles, which should mimic the characteristics of natural muscles, have an energy integration system, a yarn structure, and tensile actuation ability. We present new tensile self-powered artificial muscle yarns (SPAM) with systemic, structural, and actuation characteristics similar to those of myofibrils. To biomimic the energy conversion process of natural muscles, the presented SPAM system converts chemical energy into mechanical energy in a two-sequence stage. First, a generator converts the chemical energy into electrical energy, thereby creating an electrochemical ion gradient. Second, when the self-generated energy is applied to the actuator, the ions created by the electrochemical energy induce a change in the physical volume, which results in the contraction of the actuator. In this study, MWNT-coiled yarns were used as tri-functional yarns that simultaneously act as a generator, supercapacitor, and an actuator. This SPAM system comprises a generator with MWNT-coiled yarns (i.e., the anode) and reduced graphene oxide (RGOx) (i.e., the cathode); in addition, the MWNT-coiled yarns use an electrochemical actuator. The presented SPAM has three advantages over previously presented systems: (1) the coiled yarn structure provides a high tensile stroke; (2) the supercapacitor enables fast contraction within 2.3 s; and (3) the self-charging system enables reversible actuation

Ferroelectric-assisted high-performance triboelectric nanogenerators based on electrospun P(VDF-TrFE) composite nanofibers with barium titanate nanofillers

Triboelectric nanogenerators (TENGs) are flexible, efficient, and cost-effective energy harvesters. Here, we develop high-performance ferroelectric-assisted TENGs using electrospun fibrous surfaces based on P(VDF-TrFE) with dispersed BaTiO3 (BTO) nanofillers in either cubic (CBTO) or tetragonal (TBTO) form. TENGs with three types of tribo-negative surface (pristine P(VDF-TrFE), P(VDF-TrFE)/CBTO and P(VDF-TrFE)/TBTO) in contact with PET were investigated and output increased progressively from pristine (0.75 W/m2) to CBTO (2 W/m2) and to TBTO (2.75 W/m2). Accounting for contact pressure, the max output (Voc=315 V &Jsc=6.7 µA/cm2) is significantly higher than for TENGs having spin-coated P(VDF-TrFE)/BTO. It is hypothesized that electrospinning increases dipole alignment due to high applied voltages, but also aids the formation of a highly oriented crystalline β-phase via uniaxial stretching. Essentially, tribo-charge transfer is boosted due to increased surface potential owing to enhanced ferroelectric polarization. P(VDF-TrFE)/TBTO produced higher output than P(VDF-TrFE)/CBTO even though permittivity is nearly identical. Thus, it is shown that BTO fillers boost output, not just by increasing permittivity, but also by enhancing the crystallinity and amount of the β-phase (as TBTO produced a more crystalline β-phase present in greater amounts). Finally, the ferroelectric-assisted TENG was integrated with a flexible graphene electrode-based supercapacitor to produce a self-charging system capable of charging to 1.25 V in just 5 min. These results demonstrate that this technology can be valuable in wearable applications where higher power output, more efficient charging and flexibility are paramount.

Scalable fabrication of hierarchically structured graphite/polydimethylsiloxane composite films for large-area triboelectric nanogenerators and self-powered tactile sensing

Abstract Health monitoring, e-skin, and soft robotics call for large-area and robust energy-harvesting strategy to powering their embedded sensors and peripheral electronics. Triboelectric nanogenerator (TENG) is an optimum option to energizing self-powered sensors and self-charging systems. Herein, a large-scale facile and compatible bar-assisted printing method is presented to achieve hierarchically microstructured polymer composite triboelectric film with good hydrophobicity to improve the electrical output performance and achieve the robustness of TENG. The electrical outputs of the TENG devices are tuned by imparting the graphite fillers into polydimethylsiloxane (PDMS) with optimal concentration. The achieved microstructured graphite/PDMS composite based TENG supplies high and stable short-circuit current of 42 µA, open-circuit voltage of 410 V, and transferred charges of 160 nC under an applied force of 1.2 N, which are sufficient enough to power wearable sensors or charge the energy storage devices. The TENG devices can charge a 2.2 µf capacitor to 1.5 V within 2 s, lighten 30 commercial green LEDs, and drive an electronic watch as well. Self-powered tactile sensing has also been demonstrated by attaching the TENG devices onto a rubber glove to monitor the process in grasping objects. Furthermore, a large-scale self-powered sensor array is fabricated and utilized to map the spatial pressure distributions. This work not only demonstrates a scalable fabrication of the hierarchically microstructured polymer composite films for high-performance TENGs with high electrical outputs, excellent durability and ambient stability, but also brings insight into the development of future cost-effective and self-powered electronics.

Self-Charging System for Electric Vehicles

In this research paper is a study of a technique that is used in the charging of electric vehicles. This technique, which is registered as a patent, is represented by adding electric generators to supply the electric vehicle with a portion of the energy which is needed for it. This technique has been studied in this research paper and a number of important things have to be considered when dealing with this topic, the most important things that have been studied are the effects on the speed of the electric vehicle, the regenerative braking and the amount of energy that can be provided through this innovation. This research paper includes design of DC-DC Boost converter with two loops PID controllers and design for a Field Oriented Control (FOC) of electric AC motors. Keywords: Electric vehicles self-charging system, Boost converter with double loops controller, vector control of electric AC motors. DOI: 10.7176/ISDE/11-5-04 Publication date: September 30 th 2020

Development of a Self-Charging Lithium-Ion Battery Using Perovskite Solar Cells.

This study demonstrates the use of perovskite solar cells for fabrication of self-charging lithium-ion batteries (LIBs). A LiFePO4 (LFP) cathode and Li4Ti5O12 (LTO) anode were used to fabricate a LIB. The surface morphologies of the LiFePO4 and Li4Ti5O12 powders were examined using field emission scanning electron microscopy. The structural properties of the two powders were investigated using X-ray diffraction. The electrochemical properties of the LiFePO4-Li and Li4Ti5O12-Li half cells and of the full cell were investigated. The LiFePO4-Li4Ti5O12 full cell showed an excellent Coulombic efficiency of 99.3% after 100 cycles. CH3NH3PBI3 (MAPbI3) perovskite solar cells (PSCs) were fabricated using a spin coating technique. A single PSC showed a power conversion efficiency of 12.95%. In order to develop a self-charging system for LIBs, four single PSCs connected in series were used as an LFP-LTO battery. The integrated PSC system showed a power conversion efficiency of 12.44%. The PSC-LIB coupled device showed excellent overall self-charging conversion and a storage efficiency of 9.25%.

Free-Standing PVDF/Reduced Graphene Oxide Film for All-Solid-State Flexible Supercapacitors towards Self-Powered Systems.

The development of polymer-based devices has attracted much attention due to their miniaturization, flexibility, lightweight and sustainable power sources with high efficiency in the field of wearable/portable electronics, and energy system. In this work, we proposed a polyvinylidene fluoride (PVDF)-based composite matrix for both energy harvesting and energy storage applications. The physicochemical characterizations, such as X-ray diffraction, laser Raman, and field-emission scanning electron microscopy (FE-SEM) analyses, were performed for the electrospun PVDF/sodium niobate and PVDF/reduced graphene oxide composite film. The electrospun PVDF/sodium niobate nanofibrous mat has been utilized for the energy harvester which shows an open circuit voltage of 40 V (peak to peak) at an applied compressive force of 40 N. The PVDF/reduced graphene oxide composite film acts as the electrode for the symmetric supercapacitor (SSC) device fabrication and investigated for their supercapacitive properties. Finally, the self-charging system has been assembled using PVDF/sodium niobate (energy harvester), and PVDF/reduced graphene oxide SSC (energy storage) and the self-charging capability is investigated. The proposed self-charging system can create a pathway for the all-polymer based composite high-performance self-charging system.

Emergency rescue: the perspective and practicability of applying E-Cell electric engineering vehicles

Copying with the increasingly severe energy crisis and air pollution, new energy vehicles will be an inexorable trend in the near future. The E-Cell electric engineering vehicles will replace conventional oil-fired ones gradually. This paper analyses the current situation and tendency of EVs in brief, explains the function of E-Cell electric engineering vehicles and its roles in maintaining grid stability, peak load shifting and 24-hour emergency rescue service for EVs. Concerning technical application, this paper primarily designs vehicle intelligent terminal systems, Battery Management System(BMS), cable charging, wireless charging and self-charging systems. Finally, this paper designs the billing modes of charging process, and accounts for billing process of vehicle intelligent terminal systems by flow chart to ensure the accuracy during charging process.