新型非对称电化学电容器的电极匹配研究

活性炭负极容量的有效利用率是导致双电层电化学电容器和C/Ni(OH)2非对称电化学电容器容量性质差异的主要因素,并可将其作为非对称电化学电容器容量设计和测算的依据;本文引入Ni(OH)2正极有效活性物质概念,以正极有效活性物质的量匹配负极的设计容量,从而优化正、负极的容量匹配,改善非对称电化学电容器的容量和大电流性能.     

电化学双电层电容器用新型炭材料及其应用前景

活性炭是目前使用最为广泛的一种电化学双电层电容器（EDLC）的电极材料,但其固有的缺点制约了EDLC性能的进一步提高。用新型高性能炭电极材料可使EDLC比能量和比功率性能进一步提高。这些新型炭材料包括基于石墨层状结构的纳米门炭,基于碳纳米管阵列结构的毛皮炭,通过高温置换反应制备的骨架炭以及电极可整体成型的纳米孔玻态炭。本文介绍了这些炭材料的电化学特性及其在电化学双电层电容器中的应用,指出用这4种新型炭材料制备EDLC的比能量或比功率性能远高于目前活性炭基EDLC,具有良好的应用前景。     

碳基双电层电容器的结构、机理及研究进展

活性炭基双电层电容器是一种新型电化学能量储存装置,其储电机理是利用电极材料比较大的比表面积在电极和电解液之间形成双电层储存电荷,充放电过程中无化学反应发生。活性炭材料由于具有较大的比表面积、良好的孔结构分布、化学惰性表面等,一直是双电层电容器电极的首选材料。本文简要介绍了双电层电容器的制造工艺、应用及发展趋势。     

Nanoarchitectured Graphene‐Based Supercapacitors for Next‐Generation Energy‐Storage Applications

Tremendous development in the field of portable electronics and hybrid electric vehicles has led to urgent and increasing demand in the field of high‐energy storage devices. In recent years, many research efforts have been made for the development of more efficient energy‐storage devices such as supercapacitors, batteries, and fuel cells. In particular, supercapacitors have great potential to meet the demands of both high energy density and power density in many advanced technologies. For the last half decade, graphene has attracted intense research interest for electrical double‐layer capacitor (EDLC) applications. The unique electronic, thermal, mechanical, and chemical characteristics of graphene, along with the intrinsic benefits of a carbon material, make it a promising candidate for supercapacitor applications. This Review focuses on recent research developments in graphene‐based supercapacitors, including doped graphene, activated graphene, graphene/metal oxide composites, graphene/polymer composites, and graphene‐based asymmetric supercapacitors. The challenges and prospects of graphene‐based supercapacitors are also discussed.     

A novel carbon electrode material for highly improved EDLC performance

Porous materials, developed by grafting functional groups through chemical surface modification with a surfactant, represent an innovative concept in energy storage. This work reports, in detail, the first practical realization of a novel carbon electrode based on grafting of vinyltrimethoxysilane (vtmos) functional group for energy storage in electric double layer capacitor (EDLC). Surface modification with surfactant vtmos enhances the hydrophobisation of activated carbon and the affinity toward propylene carbonate (PC) solvent, which improves the wettability of activated carbon in the electrolyte solution based on PC solvent, resulting in not only a lower resistance to the transport of electrolyte ions within micropores of activated carbon but also more usable surface area for the formation of electric double layer, and accordingly, higher specific capacitance, energy density, and power capability available from the capacitor based on modified carbon. Especially, the effects from surface modification become superior at higher discharge rate, at which much better EDLC performance (i.e., much higher energy density and power capability) has been achieved by the modified carbon, suggesting that the modified carbon is a novel and very promising electrode material of EDLC for large current applications where both high energy density and power capability are required.     

Nanosized zinc oxides-based materials for electrochemical energy storage and conversion: Batteries and supercapacitors

Transition metal oxides(TMO) bring a novel direction for the development of energy store materials due to their excellent stability. They not only have high capacity and good cycle performance, but also are cheap and easily available. Zinc oxide(Zn O) as an important part of TMO have gradually attracted attention in the research of electrochemistry. Zn O, as a metal semiconductor with the advantages of wide band gap, possesses high ion migration rate, good chemical stability, simple preparation ...     

Polyaniline‐Intercalated Molybdenum Oxide Nanocomposites: Simultaneous Synthesis and their Enhanced Application for Supercapacitor

A new and universal synthetic strategy to hybridize metal oxides and conduct polymer nanocomposites has been proposed in this work. The simultaneous reaction process, which includes the generation of metal oxide layers, the oxidation polymerization of monomers, and the in situ formation of polymer–metal oxides sandwich structure is successfully realized and results in the unique hybrid polyaniline (PANI)‐intercalated molybdenum oxide nanocomposites. The peroxomolybdate proved to play a dual role as the precursor of the inorganic hosts and the oxidizing agent for polymerization. The as‐obtained hybrid nanocomposites present a flexible lamellar structure by oriented assembly of conductive PANI chains in the MoO₃ interlayer, and thus inherit excellent electrical performance and possess the potential of active electrode materials for electrochemical energy storage. Such uniform lamellar structure together with the anticipated high conductivity of the hybrid PANI/MoO₃ nanocomposites afford high specific capacitance and good stability during the charge–discharge cycling for supercapacitor application.     

Carbon and Carbon Hybrid Materials as Anodes for Sodium‐Ion Batteries

Sodium‐ion batteries (SIBs) have attracted much attention for application in large‐scale grid energy storage owing to the abundance and low cost of sodium sources. However, low energy density and poor cycling life hinder practical application of SIBs. Recently, substantial efforts have been made to develop electrode materials to push forward large‐scale practical applications. Carbon materials can be directly used as anode materials, and they show excellent sodium storage performance. Additionally, designing and constructing carbon hybrid materials is an effective strategy to obtain high‐performance anodes for SIBs. In this review, we summarize recent research progress on carbon and carbon hybrid materials as anodes for SIBs. Nanostructural design to enhance the sodium storage performance of anode materials is discussed, and we offer some insight into the potential directions of and future high‐performance anode materials for SIBs.     

Dual-ion hybrid supercapacitor:Integration of Li-ion hybrid supercapacitor and dual-ion battery realized by porous graphitic carbon

Lithium-ion hybrid supercapacitors(Li-HSCs) and dual-ion batteries(DIBs) are two types of energy storage devices that have attracted extensive research interest in recent years. Li-HSCs and DIBs have similarities in device structure, tendency for ion migration, and energy storage mechanisms at the negative electrode. However, these devices have differences in energy storage mechanisms and working potentials at the positive electrode. Here, we first realize the integration of a Li-HSC and a DIB to form a dual-ion hybrid supercapacitor(DIHSC), by employing mesocarbon microbead(MCMB)-based porous graphitic carbon(PGC) with a partially graphitized structure and porous structure as a positive electrode material. The MCMB-PGC-based DIHSC exhibits a novel dual-ion battery-capacitor hybrid mechanism: it exhibits excellent electronic double-layer capacitor(EDLC) behavior like a Li-HSC in the low-middle wide potential range and anion intercalation/de-intercalation behavior like a DIB in the high-potential range. Two types of mechanisms are observed in the electrochemical characterization process, and the energy density of the new DIHSC is significantly increased.     

Porous and free-standing Ti_3C_2T_x-RGO film with ultrahigh gravimetric capacitance for supercapacitors

MXene-based electrode materials exhibit favorable supercapacitor performance in sulfuric acid due to praised pseudocapacitance charge storage mechanism.However,self-stacking of conventional MXene electrodes severely restricts their electrochemical performance,especially at high loading.Herein,a flexible cross-linked porous Ti₃C₂T_x-MXene-reduced graphene oxide(Ti₃C₂T_x-RGO) film is skillfully designed and synthesized by microscopic ...     

The electrochemistry of activated carbonaceous materials: past, present, and future

Carbonaceous materials are widely used in electrochemistry. All allotropic forms of carbons??graphite, glassy carbon, amorphous carbon, fullerenes, nanotubes, and doped diamond??are used as important electrode materials in all fields of modern electrochemistry. Examples include graphite and amorphous carbons as anode materials in high-energy density rechargeable Li batteries, porous carbon electrodes in sensors and fuel cells, nano-amorphous carbon as a conducting agent in many kinds of composite electrodes (e.g., cathodes based on intercalation inorganic host materials for batteries), glassy carbon and doped diamond as stable robust and high stability electrode materials for all aspects of basic electrochemical studies, and more. Amorphous carbons can be activated to form very high specific surface area (yet stable) electrode materials which can be used for electrostatic energy storage and conversion [electrical double-layer capacitors (EDLC)] and separation techniques based on electro-adsorption, such as water desalination by capacitive de-ionization (CDI). Apart from the many practical aspects of activated carbon electrodes, there are many highly interesting and important basic aspects related to their study, including transport phenomena, molecular sieving behavior, correlation between electrochemical behavior and surface chemistry, and more. In this article, we review several important aspects related to these electrode materials, in a time perspective (past, present, and future), with the emphasis on their importance to EDLC devices and CDI processes.     

Double-layer and pseudocapacitance types of electrochemical capacitors and their applications to the development of hybrid devices

The basis of the complementary use of electrochemical capacitors (so-called supercapacitors) in hybrid electric power generation by rechargeable batteries and fuel cells is explored. Electrochemical capacitors are of two types: one where the interfacial double-layer capacitance of high specific area carbon materials is the basis of electric charge storage (as ions and electrons); and the other where pseudocapacitance, associated with electrosorption and surface redox processes at high-area electrode materials, e.g. RuO₂, or at conducting polymers, provides the basis of charge storage. The former, double-layer, type of capacitance stores charge non-faradaically while the latter type, pseudocapacitance, stores charge indirectly through faradaic chemical processes but its electrical behaviour is like that of a capacitor. Two types of hybrid battery/capacitor system are recognized: one based on combination of an electrochemical capacitor cell with a rechargeable battery or a fuel cell in a load-leveling function, e.g. in an electric vehicle power train; and the other based on combination of a faradaic battery-type electrode coupled internally with a capacitative electrode in a two-electrode hybrid module (termed an asymmetric capacitor). Optimization of operation of such systems in terms of balancing of active masses, of power and charge densities, and choice of maximum but limited states-of-discharge, is treated.     

Research progress on transition metal oxide based electrode materials for asymmetric hybrid capacitors

In the past few years, the increasing energy consumption of traditional fossil fuels has posed a huge threat to human health. It is very imperious to develop the sustainable and renewable energy storage and conversion devices with low cost and environment friendly features. Hybrid supercapacitors are emerging as one of the promising energy devices with high power density, fast charge-discharge process and excellent cycle stability. However, morphology and structure of the electrode materials exert serious effect on their electrochemical performances. In this review, we summarized recent progresses in transition metal oxide based electrode materials for supercapacitors. Different synthesis routes and electrochemical performances of electrode materials and storage mechanisms of supercapacitor devices have been presented in details. The future developing trends of supercapacitor based on metal oxide electrode materials are also proposed.     

Enhanced Electrochemical Performance of Supercapacitors via Atomic Layer Deposition of ZnO on the Activated Carbon Electrode Material

Fabricating electrical double-layer capacitors (EDLCs) with high energy density for various applications has been of great interest in recent years. However, activated carbon (AC) electrodes are restricted to a lower operating voltage because they suffer from instability above a threshold potential window. Thus, they are limited in their energy storage. The deposition of inorganic compounds’ atomic layer deposition (ALD) aiming to enhance cycling performance of supercapacitors and battery electrodes can be applied to the AC electrode materials. Here, we report on the investigation of zinc oxide (ZnO) coating strategy in terms of different pulse times of precursors, ALD cycles, and deposition temperatures to ensure high electrical conductivity and capacitance retention without blocking the micropores of the AC electrode. Crystalline ZnO phase with its optimal forming condition is obtained preferably using a longer precursor pulse time. Supercapacitors comprising AC electrodes coated with 20 cycles of ALD ZnO at 70 °C and operated in TEABF₄/acetonitrile organic electrolyte show a specific capacitance of 23.13 F g⁻¹ at 5 mA cm⁻² and enhanced capacitance retention at 3.2 V, which well exceeds the normal working voltage of a commercial EDLC product (2.7 V). This work delivers an additional feasible approach of using ZnO ALD modification of AC materials, enhancing and promoting stable EDLC cells under high working voltages.     

Nitrogen‐Doped Carbon Embedded MoS2 Microspheres as Advanced Anodes for Lithium‐ and Sodium‐Ion Batteries

Rational design and synthesis of advanced anode materials are extremely important for high‐performance lithium‐ion and sodium‐ion batteries. Herein, a simple one‐step hydrothermal method is developed for fabrication of N‐C@MoS₂ microspheres with the help of polyurethane as carbon and nitrogen sources. The MoS₂ microspheres are composed of MoS₂ nanoflakes, which are wrapped by an N‐doped carbon layer. Owing to its unique structural features, the N‐C@MoS₂ microspheres exhibit greatly enhanced lithium‐ and sodium‐storage performances including a high specific capacity, high rate capability, and excellent capacity retention. Additionally, the developed polyurethane‐assisted hydrothermal method could be useful for the construction of many other high‐capacity metal oxide/sulfide composite electrode materials for energy storage.     

电化学储能研究22年回顾

本文回顾了22年来作者的电化学储能研究活动,共分三个部分. 第一部分叙述高比能量、高比功率储能器件研究,包括锂硫电池研究（硫复合正极材料、锂硫电池制作、锂硼合金作为锂硫电池负极、硫-锂离子电池新体系）、超级电容器研究（超级活性炭、以酚醛树脂为原料制备电容炭、碳纳米管阵列中寄生准电容储能材料、氧化镍干凝胶准电容储能材料、归纳出电容炭材料的性能要求、电容器研制、确定“第四类”超级电容器）、锂离子电池研究（锂离子电池与可再生燃料电池的对决、双变价元素正极材料、磷酸钴锂正极材料、高功率锂离子电池的制作）. 第二部分叙述规模储能电池研究,包括液流电池新体系研究（蓄电与电化学合成的双功能液流电池、全金属化合物单液流电池、有机化合物正极的单液流电池）、致力于振兴铅酸电池（推广铅蓄电池新技术、铅炭电池的研究、铅酸电池新型板栅的研究）,储能电池（站）的经济效益计算方法. 第三部分叙述电动汽车发展路线研究,包括氢能燃料电池电动汽车、纯电动汽车与混合动力汽车、对我国电动汽车发展路线的建议、力争电动汽车补贴的合理化、坚守电动汽车“节能减排”宗旨、提出“发电直驱电动车”. 最后的结束语谈了三点感悟.     

Deciphering an Abnormal Layered‐Tunnel Heterostructure Induced by Chemical Substitution for the Sodium Oxide Cathode

Demands for large‐scale energy storage systems have driven the development of layered transition‐metal oxide cathodes for room‐temperature rechargeable sodium ion batteries (SIBs). Now, an abnormal layered‐tunnel heterostructure Na_0.44Co_0.1Mn_0.9O₂ cathode material induced by chemical element substitution is reported. By virtue of beneficial synergistic effects, this layered‐tunnel electrode shows outstanding electrochemical performance in sodium half‐cell system and excellent compatibility with hard carbon anode in sodium full‐cell system. The underlying formation process, charge compensation mechanism, phase transition, and sodium‐ion storage electrochemistry are clearly articulated and confirmed through combined analyses of in situ high‐energy X‐ray diffraction and ex situ X‐ray absorption spectroscopy as well as operando X‐ray diffraction. This crystal structure engineering regulation strategy offers a future outlook into advanced cathode materials for SIBs.     

基于过渡金属硫化物/还原氧化石墨烯复合物的高性能超级电容器

组装高能量密度的非对称超级电容器需要使用比电容大、 体积变化小且循环稳定性好的电极材料. 过渡金属硫化物(TMSs)与纳米碳材料的复合物是此类电极材料之一. 采用水热法合成了由Cu-Mo硫化物在微波剥离的还原氧化石墨烯表面生长的复合材料(CuS-MoS₂/MErGO). 此复合材料在电流密度为2 A/g时具有高达861.5 F/g的比电容和良好的循环稳定性. 将1.6 V的电池电压施加在由NiS/MErGO为正极, CuS-MoS₂/MErGO为负极组装成的不对称超级电容器上时, 该电容器的功率密度为1.28 kW/kg, 且能量密度保持为54.2 W·h·kg^-1. 结果表明, TMS复合材料是一种很有前途的高性能电化学储能材料, 尤其是用于非对称超级电容器的组装.     

Engineering Fast Ion Conduction and Selective Cation Channels for a High‐Rate and High‐Voltage Hybrid Aqueous Battery

The rechargeable aqueous metal‐ion battery (RAMB) has attracted considerable attention due to its safety, low costs, and environmental friendliness. Yet the poor‐performance electrode materials lead to a low feasibility of practical application. A hybrid aqueous battery (HAB) built from electrode materials with selective cation channels could increase the electrode applicability and thus enlarge the application of RAMB. Herein, we construct a high‐voltage K–Na HAB based on K₂FeFe(CN)₆ cathode and carbon‐coated NaTi₂(PO₄)₃ (NTP/C) anode. Due to the unique cation selectivity of both materials and ultrafast ion conduction of NTP/C, the hybrid battery delivers a high capacity of 160 mAh g^?1 at a 0.5 C rate. Considerable capacity retention of 94.3 % is also obtained after 1000 cycles at even 60 C rate. Meanwhile, high energy density of 69.6 Wh kg^?1 based on the total mass of active electrode materials is obtained, which is comparable and even superior to that of the lead acid, Ni/Cd, and Ni/MH batteries.     

A Molecular Pillar Approach To Grow Vertical Covalent Organic Framework Nanosheets on Graphene: Hybrid Materials for Energy Storage

Hybrid 2D–2D materials composed of perpendicularly oriented covalent organic frameworks (COFs) and graphene were prepared and tested for energy storage applications. Diboronic acid molecules covalently attached to graphene oxide (GO) were used as nucleation sites for directing vertical growth of COF‐1 nanosheets (v‐COF‐GO). The hybrid material has a forest of COF‐1 nanosheets with a thickness of 3 to 15 nm in edge‐on orientation relative to GO. The reaction performed without molecular pillars resulted in uncontrollable growth of thick COF‐1 platelets parallel to the surface of GO. The v‐COF‐GO was converted into a conductive carbon material preserving the nanostructure of precursor with ultrathin porous carbon nanosheets grafted to graphene in edge‐on orientation. It was demonstrated as a high‐performance electrode material for supercapacitors. The molecular pillar approach can be used for preparation of many other 2D‐2D materials with control of their relative orientation.