High-performance Energy Storage Research Articles

Balancing Polarization and Breakdown for High Capacitive Energy Storage by Microstructure Design.

The compromise of contradictive parameters, polarization and breakdown strength, is necessary to achieve a high energy storage performance. The two can be tuned, regardless of material types, by controlling microstructures: amorphous states possess higher breakdown strength, while crystalline states have larger polarization. However, how to achieve a balance of amorphous and crystalline phases requires systematic and quantitative investigations. Herein, we comprehensively evaluated the trade-off between polarization and breakdown field with the evolution of microstructure, i.e., grain size and crystallinity, by phase-field simulations. The results indicate small grain size (∼10-35nm) with moderate crystallinity (∼60%∼80%) is more beneficial to maintain relatively high polarization and breakdown field simultaneously, consequently contributing to a high overall energy storage performance. Experimentally, we therefore achieved an ultrahigh energy density of 131 J cm-3 with a high efficiency of 81.6% in the microcrystal-amorphous dual-phase Bi3NdTi4O12 films. This work provides a guidance to substantially enhance dielectric energy storage by a simple and effective microstructure design. This article is protected by copyright. All rights reserved.

Enhancement of Capacitive Properties of Ce-Doped MnAl2O4 Electrode for High Performance Energy Storage Applications

Enhancement of Capacitive Properties of Ce-Doped MnAl2O4 Electrode for High Performance Energy Storage Applications

Integrated Design for Discrete Sulfur@Polymer Nanoreactor with Tandem Connection as Lithium-Sulfur Battery Cathodes.

Apart from electrode material modification, architecture design and optimization are important approaches for improving lithium-sulfur battery performance. Herein, an integrated structure with tandem connection is constructed by confining nanosulfur (NS) in conductive poly(3,4-ethylenedioxythiophene) (PEDOT) reaction chambers, forming an interface of discrete independent nanoreactor units bonded onto carbon nanotubes (noted as CNT/NS@PEDOT). The unique spatial confinement and concentration gradients of sulfur@PEDOT nanoreactors (SP-NRs) can promote reaction kinetics while facilitating rapid polysulfide transformation and minimizing dissolution and diffusion losses. Meanwhile, overall ultrahigh energy input and output are achieved through tandem connection with carbon nanotubes, isolation with PEDOT coating, and synergistic multiplicative effects among SP-NRs. As a result, it delivers a high initial discharge capacity of 1246 mAh g-1 at 0.1 C and 918 mAh g-1 at 1 C, the low capacity decay rate per lap of 0.011% is achieved at a current density of 1 C after 1000 cycles. This research emphasizes the innovative structural design to provide a fresh trajectory for the further advancement of high-performance energy storage devices.

Biomass-Derived Carbon Materials for Advanced Metal-Ion Hybrid Supercapacitors: A Step Towards More Sustainable Energy

Modern research has made the search for high-performance, sustainable, and efficient energy storage technologies a main focus, especially in light of the growing environmental and energy-demanding issues. This review paper focuses on the pivotal role of biomass-derived carbon (BDC) materials in the development of high-performance metal-ion hybrid supercapacitors (MIHSCs), specifically targeting sodium (Na)-, potassium (K)-, aluminium (Al)-, and zinc (Zn)-ion-based systems. Due to their widespread availability, renewable nature, and exceptional physicochemical properties, BDC materials are ideal for supercapacitor electrodes, which perfectly balance environmental sustainability and technological advancement. This paper delves into the synthesis, functionalization, and structural engineering of advanced biomass-based carbon materials, highlighting the strategies to enhance their electrochemical performance. It elaborates on the unique characteristics of these carbons, such as high specific surface area, tuneable porosity, and heteroatom doping, which are pivotal in achieving superior capacitance, energy density, and cycling stability in Na-, K-, Al-, and Zn-ion hybrid supercapacitors. Furthermore, the compatibility of BDCs with metal-ion electrolytes and their role in facilitating ion transport and charge storage mechanisms are critically analysed. Novelty arises from a comprehensive comparison of these carbon materials across metal-ion systems, unveiling the synergistic effects of BDCs’ structural attributes on the performance of each supercapacitor type. This review also casts light on the current challenges, such as scalability, cost-effectiveness, and performance consistency, offering insightful perspectives for future research. This review underscores the transformative potential of BDC materials in MIHSCs and paves the way for next-generation energy storage technologies that are both high-performing and ecologically friendly. It calls for continued innovation and interdisciplinary collaboration to explore these sustainable materials, thereby contributing to advancing green energy technologies.

Mesoporous Mn-substituted MnxZn1-xCo2O4 ternary spinel microspheres with enhanced electrochemical performance for supercapacitor applications.

Extensive investigations have been carried out on spinel mixed transition metal oxide-based materials for high-performance electrochemical energy storage applications. In this study, mesoporous Mn-substituted MnxZn1-xCo2O4 (ZMC) ternary oxide microspheres (x = 0, 0.3, 0.5, 0.7, and 1) were fabricated as electrode materials for supercapacitors through a facile coprecipitation method. Electron microscopy analysis revealed the formation of microspheres comprising interconnected aggregates of nanoparticles. Furthermore, the substitution of Mn into ZnCo2O4 significantly improved the surface area of the synthesized samples. The electrochemical test results demonstrate that the ZMC3 oxide microspheres with an optimal Mn substitution exhibited enhanced performance, displaying the largest specific capacitance of 589.9Fg-1 at 1Ag-1. Additionally, the ZMC3 electrode maintained a capacitance retention of 92.1% after 1000 cycles and exhibited a significant rate capability at a current density of 10Ag-1. This improved performance can be ascribed to the synergistic effects of multiple metals resulting from Mn substitution, along with an increase in the surface area, which tailors the redox behavior of ZnCo2O4 (ZC) and facilitates charge transfer. These findings indicate that the incorporation of Mn into mixed transition metal oxides holds promise as an effective strategy for designing high-performance electrodes for energy storage applications.

Strong Local Polarization Fluctuations Enabled High Electrostatic Energy Storage in Pb-Free Relaxors.

Electrostatic energy-storage ceramic capacitors are essential components of modern electrified power systems. However, improving their energy-storage density while maintaining high efficiency to facilitate cutting-edge miniaturized and integrated applications remains an ongoing challenge. Herein, we report a record-high energy-storage density of 20.3 J cm-3 together with a high efficiency of 89.3% achieved by constructing a relaxor ferroelectric state with strongly enhanced local polarization fluctuations. This is realized by incorporating highly polarizable, heterovalent, and large-sized Zn and Nb ions into a Bi0.5Na0.5TiO3-BaTiO3 ferroelectric matrix with very strong tetragonal distortion. Element-specific local structure analysis revealed that the foreign ions strengthen the magnitude of the unit-cell polarization vectors while simultaneously reducing their orientation anisotropy and forming strong fluctuations in both magnitude and orientation within 1-3 nm polar clusters. This leads to a particularly high polarization variation (ΔP) of 72 μC cm-2, low hysteresis, and a high effective polarization coefficient at a high breakdown strength of 80 kV mm-1. This work has surpassed the current energy density limit of 20 J cm-3 in bulk Pb-free ceramics and has demonstrated that controlling the local structure via the chemical composition design can open up new possibilities for exploring relaxors with high energy-storage performance.

Ultrasonic-assisted hydrothermal synthesis of MNCNT-decorated SmCoO3 perovskite composite: a facile approach for high-performance energy storage applications

Ultrasonic-assisted hydrothermal synthesis of MNCNT-decorated SmCoO3 perovskite composite: a facile approach for high-performance energy storage applications

Rational design of hierarchical porous reduced graphene oxide/9,10-phenanthraquinone/porous carbon nanocomposites for high-performance supercapacitors

The development of advanced electrode material is crucial for promoting the application of new high-performance green energy storage devices and remains a great challenge. Herein, by introducing porous carbon (PC) or carbon nanotubes (CNTs) to further modify the redox-active 9,10-phenanthrenequinone (PQ) molecule non-covalently functionalized reduced graphene oxide (RGO), we have designed and synthesized RGO/PQ/PCs (RPPs) and RGO/PQ/CNTs-10 (RPC-10) nanocomposites using a simple one-step solvothermal method. Benefiting from the optimization of the hierarchical porous nanostructures and each composition further strengthens their respective advantages in the novel synthesized nanocomposites (RPPs and RPC-10), the RPPs and RPC-10 electrodes demonstrated significantly superior electrochemical energy storage performance over the RGO and RGO/PQ (RP) electrodes, especially for the RPP-10 electrode with a high specific capacitance of 343.5 F g−1 at 0.5 A g−1 and good rate capability (69.23 %, 0.5 − 40 A g−1). Furthermore, both the symmetric supercapacitor assembled with the optimal RPP-10 electrode and the hybrid supercapacitor assembled with the RPP-10 negative electrode and the NCSRC-24 positive electrode previously reported show excellent energy densities and ultra-long cycling stabilities. This result demonstrates that the synthesized novel RPP-10 nanocomposite is a highly promising candidate for new light-weight, sustainable, high-flexible and high-performance energy storage devices.

Bi-Interlayer Strategy for Modulating NiCoP-Based Heterostructure toward High-Performance Aqueous Energy Storage Devices.

Nickel-cobalt (NiCo) phosphides (NCPs) possess high electrochemical activity, which makes them promising candidates for electrode materials in aqueous energy storage devices, such as supercapacitors and zinc (Zn) batteries. However, the actual specific capacitance and rate capability of NCPs require further improvement, which can be achieved through reasonable heterostructural design and loading conditions of active materials on substrates. Herein, novel hierarchical Bi-NCP heterogeneous structures with built-in electric fields consisting of bismuth (Bi) interlayers (electrodeposited on carbon cloth (CC)) are designed and fabricated to ensure the formation of uniform high-load layered active materials for efficient charge and ion transport. The resulting CC/Bi-NCP electrodes show a uniform, continuous, and high mass loading (>3.5mg) with a superior capacitance reaching 1200 Fg-1 at 1 Ag-1 and 4129 mFcm-2 at 1 mAcm-2 combined with high-rate capability and durable cyclic stability. Moreover, assembled hybrid supercapacitors (HSCs), supercapatteries, and alkaline Zn-ion (AZBs) batteries constructed using these electrodes deliver high energy densities of 64.4, 81.8, and 319.1 Whkg-1, respectively. Overall, the constructed NCPs with excellent aqueous energy storage performance have the potential for the development of novel transition metal-based heterostructure electrodes for advanced energy devices.

Electrodeposited Cobalt Hydroxide Thin Films: A Comprehensive Investigation from Synthesis to Advanced Electrochemical Behavior for High-Performance Energy Storage

Electrodeposited Cobalt Hydroxide Thin Films: A Comprehensive Investigation from Synthesis to Advanced Electrochemical Behavior for High-Performance Energy Storage

Multifunctional activated carbon derived from novel biomass for high-performance energy storage applications: A sustainable alternative to fossil-fuel-derived carbon

Biomass-derived activated carbon materials have been attracted as low-cost and sustainable electrode materials for energy storage applications. In this work, we synthesised activated carbon from black gram whole skin for the first time, and the used source is a cost-effective carbon precursor. Nitrogen and phosphorous doping in activated carbon improved electronic conductivity, surface area and porosity. In supercapacitor application, the nitrogen and phosphorous doped activated carbon sample showed a high specific capacitance of 425 F g−1 at 0.5 A g−1 and cycling stability of about 92.5 % capacitance retention even after 5000 cycles in a three-electrode system. The observed stable specific capacitance in a three-electrode system encouraged us to make a two-electrode symmetric device, showing a specific capacitance of 100 F g−1 at 0.5 A g−1 with a higher energy density of 20 Wh kg−1. In addition, the lithium storage capability of doped carbon showed good capacity of 750 mAh g−1 at 0.1 A g−1 with a reversible capacity of 687 mAh g−1 after 100 cycles. The hetero-atom doped activated carbon derived from black gram skin showed outstanding electrochemical performance towards supercapacitor and lithium battery application, indicating a potential alternative to fossil fuel-derived carbon.

Unveiling the potential of Na2FePO4F@PEG composite as cathode material for sodium-ion batteries

The economic and environmental advantages of Na2FePO4F fluorophosphate have positioned it as a highly promising cathode material for sodium-ion batteries (SIBs). This recognition stems from its demonstrated potential to address key challenges in energy storage systems, making it a subject of extensive research and studies.In this paper, the preparation of Na2FePO4F powder through a simplified, upscaling, and cost-effective approach that involves the direct use of phosphoric acid is described, aiming to evaluate its electrochemical performance. The obtained orthorhombic structure (S.G. Pbcn) is mixed with varying percentages of polyethylene glycol as a carbon source (15% and 20%) to generate large specific surfaces, improve electronic conductivity, and achieve an optimized carbon content for these materials. The 15% and 20% PEG-coated Na2FePO4F are evaluated at a 2 - 4 V voltage range at C/15 in Na-half cells using two electrolyte formulations: 5% FEC 1 M NaClO4:PC and 1 M NaPF6:PC. The NaPF6/FEC electrolyte exhibits better electrochemical characteristics and high cycling stability, especially in the case of the 15% PEG-coated material. These findings are also supported by the data from differential plots and rate capabilities, highlighting the potential of the coated material for applications in high-performance energy storage applications.

High Volumetric Energy Density Supercapacitor of Additive-Free Quantum Dot Hierarchical Nanopore Structure.

The high surface-area-to-volume ratio of colloidal quantum dots (QDs) positions them as promising materials for high-performance supercapacitor electrodes. However, the challenge lies in achieving a highly accessible surface area, while maintaining good electrical conductivity. An efficient supercapacitor demands a dense yet highly porous structure that facilitates efficient ion-surface interactions and supports fast charge mobility. Here we demonstrate the successful development of additive-free ultrahigh energy density electric double-layer capacitors based on quantum dot hierarchical nanopore (QDHN) structures. Lead sulfide QDs are assembled into QDHN structures that strike a balance between electrical conductivity and efficient ion diffusion by employing meticulous control over inter-QD distances without any additives. Using ionic liquid as the electrolyte, the high-voltage ultrathin-film microsupercapacitors achieve a remarkable combination of volumetric energy density (95.6 mWh cm-3) and power density (13.5 W cm-3). This achievement is attributed to the intrinsic capability of QDHN structures to accumulate charge carriers efficiently. These findings introduce innovative concepts for leveraging colloidal nanomaterials in the advancement of high-performance energy storage devices.

One-Pot Ultrafast Molten-Salt Synthesis of Anthracite-Based Porous Carbon for High-Performance Capacitive Energy Storage

One-Pot Ultrafast Molten-Salt Synthesis of Anthracite-Based Porous Carbon for High-Performance Capacitive Energy Storage

High temperature electrical breakdown and energy storage performance improved by hindering molecular motion in polyetherimide nanocomposites

Polyetherimide (PEI) is widely used as a material for high temperature and high power energy storage capacitors in new energy vehicles and other fields. However, as the temperature increases, the electrical conductivity increases and the breakdown strength decreases, which greatly reduces the energy storage density of the capacitor and limits the application range. In order to clarify the influence mechanism of high temperature on the breakdown and energy storage performance of dielectrics, this paper established a charge capture and molecular displacement (CTMD) breakdown model based on the expansion motion of molecular segments to study the charge transport and molecular chain motion process of PEI nanocomposites (PNCs) at high temperature. The results show that at 100°C, compared with pure PEI, the internal maximum molecular displacement of PEI PNCs with appropriate doping content (3wt%) is reduced by 28.79%, and the breakdown strength is increased by 11.20%. Appropriate nano-doping can effectively increase the movement difficulty of molecular chains and reduce the activation volume that provides energy for charge transport. Thus, charge transport is inhibited, current density is reduced, and Joule heat accumulation is avoided. Finally, the high temperature breakdown and energy storage performance are improved.

Achieving ultrahigh energy storage performance of PBLZST-based antiferroelectric composite ceramics via interfacial polarization engineering

Antiferroelectric (AFE) ceramics can be used in pulse power devices for high power density and fast discharge. Composites are recognized as an effective strategy to combine the benefits of different materials but suffer from interfacial mismatch and interfacial polarization. In this work, a combination of high-breakdown Pb0.94La0.04(Zr0.99-xSnxTi0.01)O3 (PLZST) with high-efficiency Pb0.8925Ba0.04La0.045(Zr0.65Sn0.3Ti0.05)O3 (PBLZST) is explored to enhance energy storage performance. Via adjusting Sn content in PLZST, the difference in lattice and dielectric properties between two phases are reduced, decreasing interfacial polarization. The breakdown strength of PBLZST-PLZST is boosted from 285kVcm-1 to 345kVcm-1, with maximum polarization strength decreasing from 44 μC cm-2 to 36 μC cm-2. An recoverable energy density (Wre ~ 7.152Jcm-3) and discharged efficiency (η ~ 90.5%) has been achieved in Pb0.8925Ba0.04La0.045(Zr0.65Sn0.3Ti0.05)O3-Pb0.94La0.04(Zr0.69Sn0.3Ti0.01)O3 (x = 0.3) composite ceramics. These findings highlight the potential of interfacial polarization engineering for developing composite ceramics with high-energy storage performance.

Research and development of double layer P-doped laser induced graphene thin film electrode for flexible micro-supercapacitor applications

Laser-induced graphene (LIG) has garnered significant attention for its cost-effectiveness and high efficiency in fabricating flexible micro-energy storage devices. In this study, we devised a simple method to fabricate double layer P-doped LIG electrodes through repetitive laser induction technology for high-performance flexible energy storage applications. Instead of utilizing commercial polyimide (PI) thin film, we optimized the formation process of P-doped PI thin film and achieved a highly flexible double layer P-doped LIG thin film electrode with a uniformly porous structure and the high porosity through repeated laser induction processes. Experimental results demonstrated that the developed double layer P-doped LIG thin film electrode exhibits high porosity, high specific areal capacitance of 180 mF cm-2, and high energy density of 0.025 mWh cm-2. Furthermore, an all-solid-state micro-supercapacitor utilizing hydrogel electrolyte was assembled, demonstrating a high areal capacitance of 62 mF cm-2 and excellent cycling stability with 95% capacitance retention after 6000 charging/discharging cycles. Moreover, the developed all-solid-state micro-supercapacitor successfully powered a light-emitting diode, showcasing its significant potential for practical energy storage applications.

Agricultural and industrial wastes applied on the high performance energy storage devices

Driven by population growth, the destruction of the environment and the energy demand continue to increase dramatically. This study uses garlic skin and carbon fiber from agricultural and industrial wastes to prepare energy storage devices. Carbon quantum dots (CQDs) were obtained from garlic skin using high-temperature pyrolysis. The specific capacitance of the gel electrolyte could be effectively increased with a small number of CQDs doping. A methylcellulose-based carbon fiber-electrode was prepared by grinding and depositing the industrial recycled carbon fiber onto a biodegradable methylcellulose substrate. The methylcellulose-based recycled carbon fiber-electrode has the highest specific capacitance, energy density, and power density, which are 155 F/g, 10 Wh/kg, and 4047 W/kg, respectively, at a scan rate of 0.02 V/s, and demonstrates excellent performance, such like high specific capacitance, low internal resistance as well as rapid charge and discharge characteristics, which may have potential to replace the expensive carbon nanotubes and graphenes. The electrodes were made from recycled carbon fiber, the gel electrolyte with garlic CQDs, and a separator assembled into a sandwich structure to form supercapacitors. The capacity retention rate of the supercapacitor still retained 96 % of its initial value after 2000 cycles of charge and discharge testing at a constant current of 0.20 mA. This demonstrates the supercapacitor prepared in this study with competitive power density, energy density, high rate capability, and excellent life cycle stability by combining the garlic skin and carbon fiber from agricultural and industrial wastes, highlighting the enormous potential of agricultural and industrial wastes for energy storage applications.

High energy storage performance induced by the introduction of BiScO3 into (Bi0.5Na0.5)TiO3–BaTiO3 lead-free ferroelectric ceramics

In this work, ternary 0.25(Bi0.5Na0.5)TiO3-(0.75-x)BaTiO3-xBiScO3(abbreviated as 0.25BNT-(0.75-x)BT-xBS, x = 0.19, 0.21, 0.23, 0.25, 0.27) lead-free ferroelectric ceramics were synthesized using the solid-state reaction method. The introduction of BiScO3 into (Bi0.5Na0.5)TiO3–BaTiO3 ceramics had a significant impact on changing the phase structures, and microstructures, as well as the dielectric and ferroelectric properties. All ceramics exhibited a coexistence of tetragonal(P4bm) and rhombohedral(R3c) perovskite phases, while the influence of the BiScO3(BS) content on the average grain size was not significant. Slim polarization-electric field hysteresis loops were recorded for the 0.25BNT-(0.75-x)BT-xBS ceramics, with low remnant polarization (Pr) and large maximum polarization(Pmax). 0.25BNT-0.50BT-0.25BS ceramic had the largest Pmax, which induced a high energy storage density of 2.93 J/cm3 and energy storage efficiency of 91 % under a low electric field of 230 kV/cm 0.25BNT-0.50BT-0.25BS ceramic not only yielded excellent fatigue resistance, but also maintained good energy storage performance at high temperature and high frequency, which are considered of great importance since they can be leveraged for the potential development of high temperature and frequency capacitors. In addition, an excellent pulse performance was measured, with a high discharge energy density of 3.42 J/cm3 and a fast discharging rate t0.9 of 130 ns. This good pulse performance was maintained at high temperatures, suggesting that the proposed material is also highly competitive for applications where high-temperature pulse devices are required.

Investigation of electrochemical and photoluminescence properties of Dy[formula omitted] doped SrO/BaO/Al2O3 nanocomposite for supercapacitor and display applications

The current study investigates the synthesis and characterization of dysprosium-doped strontium barium aluminum nanocomposites (SBAD NCs), aiming to enhance their suitability for display and supercapacitor applications. SBAD NCs are synthesized by Solution combustion synthesis using aloevera extract as a reducing agent. Multi-phase formation of NCs due to SrO, BaO, and γ-Al2O3 phases was confirmed by PXRD analysis, and crystallite size is found to be in the range of 26 nm to 36 nm. SEM analysis confirmed the surface morphology and the elemental composition was affirmed by the EDAX spectrum which confirmed the purity of the synthesis. The blue shift in the UV–visible absorption peak with increasing dopant concentration suggests a rise in the direct energy band gap from 4.07 eV to 4.11 eV. FTIR analysis confirmed functional groups and fingerprint region affirmed the presence of SrO, BaO, and AlO bonds. Photoluminescence analysis performed under excitation wavelength 276 nm revealed a prominent emission peak at 565 nm, and the CIE values fall in the yellow-green region of visible spectra. The CCT value was found to be 4490 K–4542 K which might find an application as a nanophosphor in cool light-emitting diodes. The tailored nanocomposites exhibit exceptional electrochemical performance characterized by superior specific capacitance, and improved charge–discharge kinetics, as evaluated through cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The specific capacitance is found to be in the range of 103.26 F/g to 173.24 F/g at a scan rate of 10 mV/s with increasing Dy3+ dopant concentration from 1 mol% to 9 mol% respectively. The dysprosium-doped SBAD NCs emerge as promising candidates for high-performance energy storage systems and vibrant display technologies, offering a synergistic integration of efficient energy storage and vivid display functionalities.