Portable Electronic Devices Research Articles

All‐in‐One Polymer Gel Electrolyte towards High‐Efficiency and Stable Fiber Zinc‐Air Battery

Fiber zinc‐air batteries are explored as promising power systems for wearable and portable electronic devices due to their intrinsic safety and the use of ambient oxygen as cathode material. However, challenges such as limited zinc anode reversibility and sluggish cathode reaction kinetics result in poor cycling stability and low energy efficiency. To address these challenges, we design a polydopamine‐based all‐in‐one gel electrolyte (PAGE) that simultaneously regulates the reversibility of zinc anodes and the kinetics of air cathodes through polydopamine interfacial and redox chemistry, respectively. The intrinsic catechol and carboxylate groups in PAGE regulate the transport and solvation structure of Zn2+, facilitating dendrite‐free zinc deposition with a lamellar stacking morphology. Additionally, the oxidation of redox‐active catechol groups in PAGE replaces the sluggish oxygen evolution reaction on the air cathode and reduces the energy barrier for charging, enabling fiber zinc‐air batteries to achieve a significantly improved energy efficiency of 95% and a longer lifespan of 40 hours. Further integration into self‐powered electronic textiles underscores its potential for next‐generation wearable systems.

Physical and electrochemical performances of novel tellurium composite films as anode applications in energy storage systems

Portable electronic devices and electric cars use lithium-ion batteries, but clumping lithium alloys limit their lifespan. Due to their strong electronic conductivity, volumetric capacity, and high energy density, researchers are conducting research on electrochemical metal cells utilizing tellurium for high-performance batteries. Theoretically, lithium-tellurium batteries can improve energy densities three times more than lithium-ion batteries. However, metal-tellurium faces challenges such as low rate capability, unclear redox reactions, intermediate dissolution, and electrode volume changes. This study explores the enhancement of the energy storage capacity of next-generation batteries by fabricating coated electrode films as novel anodes from tellurium, silicon, and graphene. Physical, thermal, and morphological analysis of composite material are investigated by XRD, TEM, TGA, DSC, SEM, UV, and XPS analyses, revealing its rigidity as well as durability through its crystal structure alignment and thermal stability. In electrochemical analysis (CV) at various scan rates, samples that exhibit consistent and high specific capacity (Cp) values at different scan speeds (25, 50, and 100 mV/s) indicate excellent ability to store and maintain charge. Decreasing Cp values with increasing scan rates indicate that the speed of cycling limits the charge transfer kinetics and electrode performance. In EIS, the charge transfer resistances (Rct) for the pure Te, Te + Gr, Te + Si + Gr, and Te + Si samples are 759.07 Ω, 4.21 Ω, 36.39 Ω, and 164.90 Ω, respectively. The Te + Gr sample has the lowest Rct, indicating the best charge transfer efficiency at the electrode contact, whereas the Te + Si + Gr sample has a comparatively lower Rct, indicating better charge transfer kinetics. The combined result exhibits the synergistic impact of tellurium, silicon, and graphene in enhancing the energy storage capacity of future batteries across the industry.

Investigating the impact of discretization techniques on real-time digital control of DC-DC boost converters: A comprehensive analysis

This paper provides a thorough comparative analysis of discretization techniques commonly utilized in digital control applications for DC-DC boost converters (DBCs). Given the crucial role of DC-DC converters in various industries such as renewable energy systems, electric vehicles, and portable electronic devices, it is imperative to optimize their performance through efficient digital control. This study aims to improve the understanding of the effects of discretization methods on control system behaviour. It investigates their impact on the performance, stability and accuracy of control algorithms in the context of DBC, using dSPACE real-time interface (RTI) and hardware-in-the-loop (HIL) simulation for validation. This approach replicates real-world conditions, allowing performance to be evaluated in a controlled environment. The analysis examines behaviour in the time and frequency domains, providing insight into the strengths and weaknesses of each method. Experimental validation using MATLAB/Simulink/Stateflow on dSPACE RTI 1007 processor, DS2004 high-speed A/D and CP4002 timing and digital I/O boards ensures that the comparative analysis provides practical benefits for DBC digital control applications.

Analysis of NCM concentration and extraction efficiency in the lithium-ion battery extraction process

In recent years, with the increasing popularity of portable electronic devices (PEDs) and electric vehicles (EVs), the demand for lithium-ion batteries (LIBs) has continued to expand; however, the supply of raw materials such as nickel cobalt, and manganese (NCM) is limited, and it is essential to develop efficient recycling technologies. Hydrometallurgical methods, particularly extraction processes, can be used to obtain high-grade recycled LIB products with proper control of the process window. This study focused on the separation of NCM from copper (Cu) and aluminum (Al) by diluting the metal concentrations ([Me]) and adjusting the pH (using NH4OH) during extraction. For metal composition analysis, in addition to using inductively coupled plasma mass spectrometry (ICP-MS), ultraviolet–visible (UV–Vis) spectroscopy and colorimetric analysis were also employed to monitor ion concentrations. The change in solution color is directly related to the nickel (Ni) and cobalt (Co) ion concentrations. Moreover, a continuous shift in the Ni ion absorption spectra at different pH values did not occur for the Co ion absorption spectra. According to the extraction efficiency (EE%) results, the lower [Me] resulted in the higher EE% of NCM. The optimal process window was established within the range of 0.025–0.1 M and pH = 6.5–7.4.

Iron phosphides nanoparticles strongly coupled to N-doped carbon for high-efficiency oxygen reduction and evolution

Constructing composite structures is an effective strategy for tailoring the electronic configuration and balances the adsorption/desorption capability of oxygen-containing intermediates for obtaining high-performance bifunctional catalysts. Herein, an in-situ pyrolysis strategy was used to construct Fe2P nanoparticles supported on N-doped carbon (Fe2P/NC) catalyst. The DFT indicated that the catalytic activity of the as-prepared catalyst is significantly increased by the strong electronic interaction between the Fe2P nanoparticles and the nitrogen-doped carbon, which endows the catalyst with fast electron transfer capability and optimizes the free energy between the catalyst and the adsorbed intermediate, as well as the d-band center of the material. The as-synthesized Fe2P/NC has a low potential gap ΔE (ΔE = Ej=10 – E1/2) of ca. 0.75 V, a specific capacity as high as 833 mAh·gZn-1 and cycling stability for 1320 cycles at the current density of 10 mA·cm−2. Such a synthesis strategy provides an effective route to realizing applications for portable electronic Zn-air battery-related devices.

Wide-temperature and high-voltage Li||LiCoO2 cells enabled by a nonflammable partially-fluorinated electrolyte with fine-tuning solvation structure

Efficient, safe, and reliable energy output from high-energy-density lithium metal batteries (LMBs) at all climates is crucial for portable electronic devices operating in complex environments. The performance of corresponding cathodes and lithium (Li) metal anodes, however, faces significant challenges under such demanding conditions. Herein, a nonflammable electrolyte for high-voltage Li||LCO cells has been designed, including partially-fluorinated ethyl 4,4,4-trifluorobutyrate (ETFB) as the key solvent, guided by theoretical calculations. With this ETFB-based electrolyte, Li||LCO cells exhibit enhanced reversible capacities and superior capacity retention at an elevated charge voltage of 4.5 V and a wide operating temperature range spanning from −60 °C to 70 °C. The cells achieve 67.1% discharge capacity at −60 °C, relative to room temperature capacity, and 85.9% 100th-cycle retention at 70 °C. The outstanding properties are attributed to the LiF-rich interphases formed in the ETFB-based electrolyte with a fine-tuned solvation structure, in which the coordination environment in the vicinity of Li+ cations and the distance between anion and solvents are subtly adjusted by introducing ETFB. This solvation structure has been mutually elucidated through joint spectra characterizations and atomistic simulations. This work presents a new strategy for the design of electrolytes to achieve all-climate reliable and safe application of LMBs.

Optimizing damage resistance and structural evolution in CaO-modified Li2O-Al2O3-B2O3-TiO2-P2O5 glass-ceramics

Aluminoborate glass, recognized for its remarkable crack resistance, presents significant potential as a cover material for portable electronic devices. Nevertheless, its relatively low hardness has been a limiting factor. This study synthesized a series of 11 Li2O-30 Al2O3-(55-x) B2O3-2 TiO2-2 P2O5-xCaO (wt%), with x varying from 0 to 10, employing the melt-cast method. The resultant glass-ceramics were produced via heat treatment at 590 °C for 2 h, followed by a systematic examination of their structural and mechanical properties. The investigation demonstrated that an increase in CaO content diminishes crystallization and induces a morphological transition in the crystalline phases from granular and short rod-like structures to lath-like formations, which subsequently impacts the coordination environment of Al and B atoms. With a CaO content of 2 %, the GC2 sample precipitated Li(Al7B4O17) and Li2AlB5O10 phases, achieving a compressive strength (CR) value of 15.0 N, a hardness of 7.51 GPa, and a fracture toughness of 1.50 MPa m0.5. This glass-ceramic exhibited optimal scratch resistance and visible light transmittance exceeding 85 %, underscoring its considerable promise for application as smartphone cover glass due to its impressive overall damage resistance.

Photo-assisted self-chargeable aqueous Zn-ion energy storage device

The ever-growing demand for portable electronic devices in various applications emphasizes the necessity for continuous power sources, particularly in situations where recharging is not readily available. Although photo-assisted aqueous Zn-ion energy storage devices show promise, their slow charging rates and limited sunlight hours impede their practicality. In this study, we present a new self-charging energy storage device by investigating chemical processes for air-based recharging in photo-assisted Zn-ion technology, utilizing VO2/WO3 as a cathode. This research marks the first utilization of WO3 as a charge-separating layer alongside VO2 in photo-assisted energy storage devices. Under consistent light exposure, the electrode demonstrates a 170% increase in capacity, confirming the effectiveness of the photo-assisted charge separation mechanism. Moreover, the air-based charging achieves an Open Circuit Potential (OCP) of 1 V, reaching 0.9 V OCP within 140 s. Incorporating this technology into a double cathode-based device successfully powers small LED devices, showcasing the practicality of this approach. These discoveries pave the way for the advancement of self-rechargeable photo-assisted energy storage devices for real-world usage.

Cobalt Ferrite@Barium titanate core-shell nanoparticles empowered triboelectric electromagnetic coupled nanogenerator for self-powered electronics

In pursuing sustainable energy solutions for wearable technology and Internet of Things (IoT) devices, achieving high power in self-powered electronics is a significant challenge. This study introduces a novel hybrid nanogenerator by integrating a triboelectric nanogenerator (TENG) and an electromagnetic generator (EMG) to achieve both high voltage and high current outputs simultaneously. The cobalt ferrite barium titanate (CoFe2O4@ BaTiO3) core–shell nanoparticles (NPs) were chosen for their unique ability to enhance the system’s performance by combining triboelectric, piezoelectric, and electromagnetic properties. The BaTiO3 shell exhibited robust triboelectric and piezoelectric properties essential for TENG operation, while the CoFe2O4 core, influenced by the EMG’s magnetic field, induces additional static charges, significantly boosting overall energy conversion efficiency. The TENG and EMG in the combined system operate together in a contact-separation mode, where their in-phase output signals are seamlessly combined via a double bridge rectifier, resulting in a robust power output of 37.7 mW and a power density of 1.86 mW/cm2, with cycling stability of over 10,000 cycles. The uniquely designed TENG-EMG combined nanogenerator (C-TENG) exhibited striking adaptability, effectively operating across different low-to-high frequencies and load situations while constantly powering portable electronic devices. This innovative approach meets the high energy demands of modern self-powered electronics with exceptional efficiency, durability, and high-power density, positioning it as a versatile solution for wearable biomechanical energy harvesting.

Development of a Non-Linear Battery Management System Model for Lithium-Ion Batteries Using MATLAB Simulation

Abstract: This research focuses on developing a comprehensive battery model tailored for Battery Management Systems (BMS) using lithium-ion batteries. Given the increasing reliance on lithium-ion batteries in electric vehicles and portable electronic devices, this study aims to construct a non-linear battery model that accurately reflects the charging and discharging characteristics under various load conditions. The research identifies suitable characteristics of lithium-ion batteries essential for effective battery model construction. A MATLAB-Simulink approach is employed to build the model, which integrates both charging and discharging processes into a single simulation framework. This merged model enhances the existing non-linear models by offering improved accuracy in simulating battery behavior under fixed parameters. The outcome is expected to provide a reference model for future studies and applications in power management systems. Additionally, this research underscores the critical role of BMS in extending battery life and ensuring safety, making it a significant contribution to the field of energy management. The study's findings highlight the potential of the proposed model to serve as a foundation for further research and development in battery technologies.

Flexible Fiber Shaped Self-Powered System Based on Conductive PANI for Signal Sensing and Energy Harvesting.

As science and technology advance, people are increasingly inclined to use sustainable and portable wearable electronic devices. The traditional supporting power source, batteries, suffers from issues of flexibility and lifespan, severely constraining the development of wearable devices. Alternatively, the self-powered system, serving as a power source, can effectively collect energy from the surrounding environment, achieving maintenance-free operation and high adaptability, which has attracted widespread research. The coaxial fiber-structured self-powering system proposed in this study is based on a supercapacitor (SC) and a triboelectric nanogenerator (TENG). The carbon fiber (CF) has polyaniline (PANI) and rGO connected to it, and a friction layer of silicone rubber is wrapped around the outside. The conductivity of the fiber was increased by multiple PANI graftings, and a coaxial fiber-type TENG with a 2 mm diameter was created. Following weaving, the TENG displays a high power density of 576 mW m-2 and an open-circuit voltage of 160 V and a short-circuit current of 9 μA. In addition, the flexible fiber-shaped supercapacitor uses NiAl-LDHs@CF as the negative electrode and AC@CF as the positive electrode, showing a specific capacitance of up to 281.4 mF cm-2. Furthermore, the SC and TENG are assembled into a coaxial self-power supply system, which has excellent performance and shows extensive potential applications in the field of wearable device power supply.

Enhanced Epoxy Composites Reinforced by 3D-Aligned Aluminum Borate Nanowhiskers.

Recently, the durability of high-performance and multifunctional portable electronic devices such as smartphones and tablets, has become an important issue. Electronic device housing, which protects internal components from external stimuli, such as vibration, shock, and electrical hazards, is essential for resolving durability issues. Therefore, the materials used for electronic device housing must possess good mechanical and electrical insulating properties. Herein, we propose a novel high-strength polymer nanocomposite based on 3D-aligned aluminum borate nanowhisker (ABOw) structures. ABOw was synthesized using a facile hydrothermal method, and 3D-aligned ABOw structures were fabricated using a freeze-casting process. The 3D-aligned ABOw/epoxy composites consist of repetitively layered structures, and the microstructures of these composites are controlled by the filler content. The developed 3D-aligned ABOw/epoxy composite had a compressive strength 56.72% higher than that of pure epoxy, indicating that it can provide high durability when applied as a protective material for portable electronic devices.

High-performance porous activated carbon derived from Acacia catechu bark as nanoarchitectonics material for supercapacitor applications

BackgroundThe increasing energy demands stemming from the extensive utilization of portable electronic devices are creating a huge energy deficit between demand and supply. In this scenario, it is not only sufficient to pursue and innovate the new renewable energy sources but also requires an ideal device for energy storage and conversion. MethodsIn this work, activated carbon (AC) was prepared from matured bark of Acacia catechu through a series of steps; pre-carbonization, carbonization, and activation. The AC was synthesized at different temperatures (400–800 °C) under inert atmosphere, using orthophosphoric acid as an activator. As-prepared sample (ACBH) was characterized by well-known characterization techniques. Energy storage capability was assessed in terms of Cyclic voltammetry, Galvanostatic charge-discharge, Electrochemical impedance, and Cyclic stability by three-electrode setup. Significant findingsThe ACBH-8 sample demonstrated superior electrochemical performance compared to other samples. The sample ACBH-8, as Negatrode, exhibited a specific capacitance of 282.4 F g−1 at 0.5 A g−1 and retained 95.4 % cyclic stability under 10,000 cycles. The excellent energy storage performance by green-class negatrode materials from the bio-waste substance empowers commercial applications.

Highly stable Ag@Au nanowires micromesh as transparent conductive network for stretchable electrochromic modulator

The stretchable electrochromic modulator is one of the most promising energy-saving optoelectronic devices that can be integrated into smart portable and wearable electronics. A lot of focus has been on developing transparent conductive electrodes of stretchable electrochromic modulators, but they generally suffer from poor chemical stability, low photoelectric balance, and unsatisfactory deformability. To address this challenge, we first develop Ag@Au nanowires (NWs) micromesh-based stretchable transparent conductive electrodes (STCEs) using a self-assembled approach, which displays superior photoelectric performance (8.5 Ω sq-1 with a transmittance of 81.5 %), good chemical stability in harsh electrolyte environment (acidic and alkaline) as well as robust mechanical stability (bending, folding, stretching and twisting). As a demonstration, the grown WO3 on Ag@Au NWs-based STCEs can deliver good electrochromic stability even after bending over 1000 cycles and stretching to 50 %. Moreover, highly soft Zn//WO3 and polyaniline (PANI)//WO3 electrochromic modulators were assembled using flexible Ag@Au micromesh STCEs, which still retain uniform electrochromism in neutral and acidic electrolytes respectively. Definitionally, the strategy of in-situ grown Au shell on the surface of AgNWs micromesh provides an innovative solution to fabricate high-performance STCEs for the related portable smart wearable electronic devices.

MOF Derived Ni‐Cu Double Hydroxide Based Self‐Powered Flexible Asymmetric Supercapacitor Using Onion Scale as an Effective Bio‐Piezoelectric Separator

Modern electronic devices necessitate the utilization of compact, wearable, and flexible substrates capable of simultaneously harvesting and storing energy by merging traditional energy harvesting techniques with storage mechanisms into a singular portable device. Here, we present the fabrication of a low‐cost, sustainable, all‐solid‐state, self‐powered flexible asymmetric supercapacitor (SPASC) device. This device features MOF‐derived nickel‐copper double hydroxide nanosheets coated stainless steel (SS) fabric sheet (NCDH@SS) as the positive electrode, while manganese dioxide decorated activated porous carbon on SS fabric sheet (MnO2‐APC@SS) acts as the negative electrode. The electrodes are isolated by a PVA‐KOH gel electrolyte, while onion scale, a bio‐piezoelectric separator, ensures effective separation. The self‐charging ability of the device is demonstrated through mechanical deformation induced by finger imparting. This rectification‐free SPASC device exhibits remarkable performance, achieving a charge up to ~235.41 mV from the preliminary open circuit voltage of ~20.89 mV within 180 s under ~16.25 N of applied compressive force (charged up to ~214.52 mV). Furthermore, three SPASC devices connected in series can power up various portable electronic devices like wristwatches, calculators, and LEDs upon frequent imparting. Our work thus demonstrates an innovative and advanced approach towards the development of sustainable, flexible, and advanced self‐powered electronics.

Flexible zinc-ion hybrid supercapacitor based on Co2+-doped polyaniline/V2O5 electrode

With the rapid advancement of renewable energy sources and portable electronic devices, the demand for high-performance energy storage systems is growing, driving continuous progress in supercapacitor technology. Zinc-ion hybrid supercapacitors (ZIHS), known for their higher safety, cost-effectiveness, and environmental friendliness, have become a hot research topic. Vanadium pentoxide (V2O5) possesses flexible multivalence, low cost, low toxicity, wide voltage window, high capacitance, and high energy density. However, its poor electrical conductivity and low cycling stability hinder its electrochemical performance, thus limiting its application in ZIHS. Here, we propose a novel strategy of incorporating Co2+ ions and conductive polyaniline (PANI) with V2O5 (CoVO-PANI) as cathode materials for ZIHS. The synergistic effect between cobalt ions and polyaniline have led to an expansion of the interlayer spacing in CoVO-PANI, which reduce the binding energy of Zn2+ ion insertion, decrease the diffusion barrier of Zn2+ ion insertion, and enhanced the electronic conductivity of the material for electron transport. In result, the CoVO-PANI@CC//2 M ZnSO4//AC@CC can reach the areal capacitance of 847.3 mF cm−2 at 1 mA cm−2. Following 2000 times at 50 mA cm−2, the CoVO-PANI@CC//2 M ZnSO4//AC@CC maintains a retention rate of 81.37 %, and can achieve a Coulombic efficiency of 100 %. The assembled flexible ZIHS device exhibits excellent flexibility and stability, with an areal capacitance of 775.6 mF cm−2 at 1 mA cm−2. This work demonstrates the tremendous potential of CoVO-PANI@CC as a cathode material for ZIHS.

Cutting-edge technologies and recent modernization on multifunctional perovskite materials for green energy conversion and spintronic applications

This featured letter summarizes the recent developments in green energy and spintronic technologies based on multifunctional i.e., multiferroic (MF) and magnetoelectric (ME) materials. These are non-toxic materials, find applications in spintronic, non-volatile memory devices, microelectromechanical systems (MEMS), photovoltaics and next generation IC miniaturization devices. Recent studies on MF and ME materials have probed and analyzed significant properties such as evidence of photo-response and significant power conversion efficiency (PCE) of multiferroic-based solar cells (SCs), evidence of electro-caloric effect (ECE) which find usage in non-toxic solid state refrigeration devices, photo- and electro-catalytic activities for green hydrogen generation, magnon-phonon coupling and existence of magnon polarons which can facilitate spintronic device technology and thermal Hall effect and, hybrid nano-generators utilized to empower portable electronic devices. All such applications are comprehensively analyzed in-depth in this letter.

MXene/Zwitterionic Hydrogel Oriented Anti‐freezing and High‐Performance Zinc–Ion Hybrid Supercapacitor

AbstractWith the wide application of portable electronic devices, zinc–ion hybrid supercapacitors (ZIHCs) have aroused great interest. However, balancing the low‐temperature performance and high energy density of ZIHCs remains a huge challenge. Herein, a zwitterionic hydrogel electrolyte (ZHE) loaded with carboxymethylcellulose and MXene is designed for ZIHCs, which shows excellent frost resistance and high output voltage. Carboxymethylcellulose and MXene enhance the flexibility and conductivity of the zwitterionic hydrogel electrolyte. Moreover, When ZnCl2 is introduced into a gel electrolyte, it induces an increase in the rate of ion transport, which enables a broadening of the operating temperature of the hydrogel (−40 °C–25 °C). As a result, Zn//AC ZIHCs based on ZHE show a high voltage window of 2 V, a high energy density (specific capacity) of 137 Wh kg−1 (247 F g−1), and the potential for wearable devices. This study will provide an effective strategy for the design of hydrogel ZIHCs with wide voltage windows, high energy density, and high practicality.

Deep eutectic solvent and laser-reduced graphene oxide: Synergistic effects in ternary nanocomposite supercapacitors

In recent years, flexible supercapacitors (FSCs) have gained considerable attention as reliable power supplies for wearable and portable electronic devices. However, optimizing both energy and power densities remains a challenge and requires effective enhancement of two key components: the electrolyte and the electrode. To address this, we have developed a new and efficient approach to FSC fabrication using a ternary nanocomposite of laser-reduced graphene@polyaniline/NiFe₂O₄(LrGO@Pani-NF) as the electrode and stable polymer hydrogels as the electrolyte. Also, we constructed FSC devices using a cross-linked poly (vinyl alcohol)/deep eutectic solvent (DES) gel electrolyte (PVA/ChCl/EG) and a PVA/Polyaniline/Nickel Ferrite gel electrolyte (PVA/Pani/NF). Among these devices, the LrGO@Pani-NF//LrGO@Pani-NF demonstrated a remarkable energy density of 48.4 Wh kg⁻¹ at 401.8 W kg⁻¹ and a long cycle life of 1000 cycles with 96.9 % capacity retention at 2 mA cm⁻². Furthermore, the supercapacitors assembled with the DES gel exhibited excellent stability at higher voltages, operating within a potential window of −3.0–3.0 V. This work not only enhances FSC electrochemical performance with graphene nanocomposite electrodes but also introduces a novel method for FSC design using conductive, stable gel electrolytes, thereby improving energy storage capabilities under harsh conditions.

Sustainable energy harvesting from medical waste: Utilizing discarded ointment tubes in triboelectric nanogenerators

Medical waste management is a common global issue that causes environmental pollution and poses significant health risks. The present study introduces a sustainable approach to addressing this issue by utilizing discarded medical ointment tubes to fabricate Triboelectric Nanogenerators (TENGs) for energy harvesting applications. The discarded metallic ointment tubes with epoxy resin coating inside simplify the TENG fabrication. The fabricated metallic ointment tube-based TENG produces a maximum output voltage of ∼ 405 V and a current of ∼ 82 µA, with a power density of 658 mW/m2. Further, TENG was utilized to power 480 LEDs and portable electronic devices with the help of an energy management system. The present work highlights the potential of transforming medical waste into sustainable energy resources.