The NASICON-type Na4MnV(PO4)(3) (NMVP) possesses potential as a cathode material in SIBs, and is known for its stable 3D Na+ superconductive framework, high voltage platform, and relatively low cost and toxicity. Neve...
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The NASICON-type Na4MnV(PO4)(3) (NMVP) possesses potential as a cathode material in SIBs, and is known for its stable 3D Na+ superconductive framework, high voltage platform, and relatively low cost and toxicity. Nevertheless, the intrinsic poor electronic conductivity and Jahn-Teller effect from Mn3+ during cycling limit its further application. Herein, to address such issues, a well-designed 3D porous spheroidal Ce3+-doped NMVP@CeO2/C cathode was constructed via a simple spraying drying-assisted route. As proved, the synergistic effect of Ce3+ doping in the crystal framework and CeO2 surface coating was achieved simultaneously, which greatly improved the electronic conductivity, facilitated the ion diffusion transfer and stabilized the crystalline structure. As a result, the as-prepared sample delivered superior discharge performance (50.3 mA h g(-1) at 50C) and long circular life (91.0 mA h g(-1) after 2000 cycles at 5C with 86.7% capacity retention). Furthermore, the reversible biphasic reaction for cathodes was confirmed by Galvanostatic intermittent titration technique (GITT) and ex situ XRD. The DFT calculation revealed the influence of Ce3+-doping on the crystalline framework and electrochemical properties. Finally, the optimized NMVP cathode also showed great potential for practical utilization through the successful assembly of full cells.
Epsilon-near-zero (ENZ) materials, a new class of materials with vanishing permittivity, which can significantly enhance the interaction between incident light and matters. Here, we investigated the third-order nonlin...
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Epsilon-near-zero (ENZ) materials, a new class of materials with vanishing permittivity, which can significantly enhance the interaction between incident light and matters. Here, we investigated the third-order nonlinear optical response of titanium nitride (TiN), an ENZ material, in the visible range by using Z-scan method, and obtained a maximum nonlinear absorption coefficient beta of-3.78 x 103 cm/GW at its ENZ wavelength. Furthermore, the carriers dynamic characteristics of TiN are revealed by time-resolved pump-probe measure-ment, including the intraband and interband excitation, the former is mainly derived from laser-induced to form a non-equilibrium distribution of hot electrons, resulting in the electron energy redistribution process in the conduction band, and the latter is the electrons located in the valence band being promoted to the conduction band, increasing the total free carrier density and thus causing a change in the optical properties. Our results indicate the great potential applications of TiN in nonlinear optical and all-optical modulation devices.
The large-scale application of measurement devices, programmable controllers, and power electronic devices increases the likelihood of distributed energy storage systems suffering from various disturbances, thus affec...
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The large-scale application of measurement devices, programmable controllers, and power electronic devices increases the likelihood of distributed energy storage systems suffering from various disturbances, thus affecting the stable operation of the system. In this paper, an adaptive finite time fast resilient control strategy is proposed for the unknown transmission disturbance in the control channel of distributed energy storage system. Firstly, the adverse effects of sensor and actuator disturbances on conventional consensus-based secondary control strategies are quantitatively analyzed. Secondly, an resilient control protocol with adaptive compensation mechanism based on terminal sliding mode is proposed, and the suppression mechanism of the controller to the unknown disturbance of the sensor and the actuator is analyzed, and the finite time convergence of the proposed distributed resilient secondary control strategy is proved theoretically. Experimental results show that the proposed control strategy is correct and effective.
Different line resistances between battery energy storage systems (BESSs) and the bus cause the problem of state-of-charge (SOC) unbalance between the batteries. SOC unbalance brings about battery over-charge or over-...
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Different line resistances between battery energy storage systems (BESSs) and the bus cause the problem of state-of-charge (SOC) unbalance between the batteries. SOC unbalance brings about battery over-charge or over-discharge, which reduces the battery life. This paper proposes an SOC feedback control strategy to achieve both output power sharing and SOC equalization between the BESSs. The average SOC of the batteries is set as the reference of each SOC control loop, and the control objectives are achieved by regulating the output voltage of the energy storage converters. The state space model of the proposed control method is established for stability analysis and control parameter design. The parameters are then designed in detail according to the dynamic and steady-state performance. Simulation and experiment verified that the proposed control strategy can achieve accurate SOC equalization and output power sharing when the line resistances and the battery capacities are different.
Silicon oxides (SiOX) based materials with great specific capacity and suitable working potential have caused widespread concern. During alloying process, the volume expansion of SiOX is approximately 200%, which limi...
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Silicon oxides (SiOX) based materials with great specific capacity and suitable working potential have caused widespread concern. During alloying process, the volume expansion of SiOX is approximately 200%, which limits its practical application for lithium-ion batteries (LIBs). For the purpose of surmounting the shortcomings of large volume change, a lot of efforts have been made, such as regulating the structure and morphology of active materials, incorporating with other conductive materials, and matching the suitable battery systems. However, to date, the volume expansion of SiOX anode in the cycle process cannot be absolutely avoided due to its intrinsic characteristics. In this work, these seeming drawback is creatively exploited to increase the electrochemical performance of SiOX materials. PbZr0.52Ti0.48O3 (PZT) is taken advantage as functional addition agent, which is based on piezoelectric effect elicited by volume expansion of SiOX. Specifically, the large volume change of SiOX- C could be transmitted to PZT particles, thus resulting in a polarization process. Then the piezoelectric potential is generated, so as to promote Li + mobility. SiOX-C/PZT was synthesized via a sol-gel method and high energy ball-milling procedure. Accordingly, SiOX-C/PZT anode exhibits excellent the superior cycling capability, it retains 570 mA h g(-1) after 200 cycles at 400 mA g(-1). Besides, it also has stable long-cycling life (430 mA h g(-1) after 500 cycles at 500 mA g(-1) with a retention of 75%). The relevant results demonstrate that PZT piezoelectric material can favorably increase the electrochemical property of SiOX anode materials.
Due to the higher specific capacity and operating voltage platform of the ternary cathode material (LiCoxNiyMn1-x-yO2), it has a specific market application in the electric vehicle (EV) industry. Gel polymer electroly...
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Due to the higher specific capacity and operating voltage platform of the ternary cathode material (LiCoxNiyMn1-x-yO2), it has a specific market application in the electric vehicle (EV) industry. Gel polymer electrolytes (GPEs) have proven to be an effective method of resolving this issue. As a result of its high conductivity and safety performance, pentaerythritol tetraacrylate (PETEA) is a promising gel polymer electrolyte. Butyl methacrylate (BMA) was successfully grafted onto PETEA to decrease its stiffness in this study. Surprisingly, after cycling for 100 cycles at a rate of 2 C, the cycle retention rate of the half-cell of NCM523/GPE/Li reached 63.9%, whereas the utilization of liquid electrolyte ceased to function normally. The successfully prepared PETEA-g-BMA GPE by in-situ thermal polymerization formed a three-dimensional network structure. The PETEA-g-BMA GPE effectively protected the structure of the cathode material during the lithium-ion charging and discharging process, inhibited the occurrence of side reactions, and minimized the risk of thermal runaway. The straightforward preparation process and low cost make industrial applications a possibility in the future. (C) 2021 Elsevier Inc. All rights reserved.
Aqueous zinc ion batteries are anticipated to succeed lithium-ion batteries as the upcoming generation of eco-friendly energy storage systems due to their high safety profile and environmental friendliness. Neverthele...
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Aqueous zinc ion batteries are anticipated to succeed lithium-ion batteries as the upcoming generation of eco-friendly energy storage systems due to their high safety profile and environmental friendliness. Nevertheless, the development of aqueous zinc ion batteries has been impeded by obstacles such as Zn dendrites, hydrogen evolution reaction, corrosion, and passivation of the Zn anode. Researchers have used various strategies to address the problems faced by Zn anodes, including the construction of artificial interface protection layers, development of functional separators, optimisation of electrolyte additives, and zinc alloying. Among them, an idea called ion-confinement effect can be easily extracted from them. With the ion-confinement effect, the passage of zinc ions through the specific structure of the material can be regulated, resulting in uniform zinc ion flux and a dendrite-free anode. This review systematically summarises the application of ion-confinement effect in the construction of artificial interface coatings and functional separators, and then discusses in detail the mechanism of ion-confinement effect in various materials, including carbon materials, inorganic materials, 3-dimensional framework materials, biomass-based materials and polymers. Finally, an outlook on the development of ion-confinement interaction is given.
Multiple demand responses and electric vehicles are considered, and a micro-grid day-ahead dispatch optimization model with photovoltaic is constructed based on stochastic optimization theory. Firstly, an interruptibl...
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Multiple demand responses and electric vehicles are considered, and a micro-grid day-ahead dispatch optimization model with photovoltaic is constructed based on stochastic optimization theory. Firstly, an interruptible load model based on incentive-based demand response is introduced, and a demand response mechanism for air conditioning load is constructed to implement an optimal energy consumption curve control strategy for air conditioning units. Secondly, considering the travel demand and charging/discharging rules of electric vehicles, the electric vehicle optimization model is built. Further, a stochastic optimization model of micro-grid with demand response and electric vehicles is developed because of the uncertainty of photovoltaic power output. Finally, the simulation example verifies the effectiveness of the proposed model. The simulation results show that the proposed model can effectively tackle the uncertainty of photovoltaic, as well as reduce the operating cost of micro-grid. Therefore, the effective interaction between users and electric vehicles can be realized.
This paper introduces a novel hybrid control strategy for quadrotor UAVs inspired by neural dynamics. Our approach effectively addresses two common issues: the velocity jump problem in traditional backstepping control...
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This paper introduces a novel hybrid control strategy for quadrotor UAVs inspired by neural dynamics. Our approach effectively addresses two common issues: the velocity jump problem in traditional backstepping control and the control signal chattering in conventional sliding mode control. The proposed system combines an outer-loop bioinspired backstepping controller with an inner-loop bioinspired sliding mode controller, ensuring smooth trajectory tracking even under external disturbances. We rigorously analyzed the system's stability using Lyapunov stability theory. To validate our algorithm's effectiveness, we conducted trajectory tracking experiments in both disturbance-free and step-disturbance conditions, comparing it with the traditional backstepping control, conventional sliding mode control, and saturated sliding mode control. The results demonstrate that our algorithm not only tracks trajectories more effectively but also significantly outperforms these methods in suppressing velocity jumps and signal chattering.
作者:
Wang, Shi-jieLiang, KangLi, Jian-binHuang, Xiao-bingRen, Yu-rongChangzhou Univ
Jiangsu Prov Engn Res Ctr Intelligent Mfg Technol Sch Mat Sci & Engn Changzhou Key Lab Intelligent Mfg & Adv Technol Po Changzhou 213164 Peoples R China Hunan Univ Arts & Sci
Coll Chem & Mat Engn Hunan Prov Key Lab Water Treatment Funct Mat Hunan Prov Key Lab Control Technol Distributed Ele Changde 415000 Peoples R China
Structurally stable Na3V2(PO4)2F3 (NVPF) is regarded as a promising cathode due to its large theoretical specific capacity. However, the poor electrical conductivity of NVPF results in poor rate capability. Herein, th...
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Structurally stable Na3V2(PO4)2F3 (NVPF) is regarded as a promising cathode due to its large theoretical specific capacity. However, the poor electrical conductivity of NVPF results in poor rate capability. Herein, the tNVPF with dense textured microsphere structure was prepared by sodium dodecyl benzene sulfonate (SDBS)-assisted solvothermal method. The unique microstructure assembled by-100 nm nanorods provides massive active sites and promotes the fast transmission of Na + carriers. The electronic conductivity of tNVPF is further improved through coating by carbonizing polyacrylamide (PAM) to form tNVPF@C with great Na+ storage performance. Textured carbon-coated Na3V2(PO4)2F3(tNVPF@C) microspheres deliver a highly specific capacity (113.6/74.7 mAh center dot g- 1 at 0.2/10 C) and better long-term cycling performance with capacity retention ratio of 80.1% after 300 cycles at 5 C. Remarkably, the Na-ion full cell, which is assembled by commercial hard carbon as anode and tNVPF@C as cathode, can achieve a high capacity of 118.9 mAh center dot g-1 and energy density of 322.6 W h center dot kg- 1.
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