Biomass‐Derived Carbon Materials as Prospective Electrodes for High‐Energy Lithium‐ and Sodium‐Ion Capacitors

Biomass‐derived carbon materials have received special attention as efficient, low‐cost, active materials for charge‐storage devices, regardless of the power system, such as supercapacitors and rechargeable batteries. In this Minireview, we discuss the influence of biomass‐derived carbonaceous materials as positive or negative electrodes (or both) in high‐energy hybrid lithium‐ion configurations with an organic electrolyte. In such hybrid configurations, the electrochemical activity is completely different to conventional electrical double‐layer capacitors; that is, one of the electrodes undergoes a Faradaic reaction, whilst the counter electrode undergoes a non‐Faradaic reaction, to achieve high energy density. The use of a variety of biomass precursors with different properties, such as surface functionality, the presence of inherent heteroatoms, tailored meso‐/microporosity, high specific surface area, various degrees of crystallization, calcination temperature, and atmosphere, are described in detail. Sodium‐ion capacitors are also discussed, because they are an important alternative to lithium‐ion capacitors, owing to the low abundance and high cost of lithium. The electrochemical performance of carbonaceous electrodes in supercapacitors and rechargeable batteries are not discussed.     

Design Strategies for Vanadium‐based Aqueous Zinc‐Ion Batteries

Aqueous zinc‐ion batteries (ZIBs) are considered promising energy storage devices for large‐scale energy storage systems as a consequence of their safety benefits and low cost. In recent years, various vanadium‐based compounds have been widely developed to serve as the cathodes of aqueous ZIBs because of their low cost and high theoretical capacity. Furthermore, different energy storage mechanisms are observed in ZIBs based on vanadium‐based cathodes. In this Minireview, we present a comprehensive overview of the energy storage mechanisms and structural features of various vanadium‐based cathodes in ZIBs. Furthermore, we discuss strategies for improving the electrochemical performance of vanadium‐based cathodes; including, insertion of metal ions, adjustment of structural water, selection of conductive additives, and optimization of electrolytes. Finally, this Minireview offers insight into potential future directions in the design of innovative vanadium‐based electrode materials.     

Halide‐Based Materials and Chemistry for Rechargeable Batteries

Rechargeable batteries are considered one of the most effective energy storage technologies to bridge the production and consumption of renewable energy. The further development of rechargeable batteries with characteristics such as high energy density, low cost, safety, and a long cycle life is required to meet the ever‐increasing energy‐storage demands. This Review highlights the progress achieved with halide‐based materials in rechargeable batteries, including the use of halide electrodes, bulk and/or surface halogen‐doping of electrodes, electrolyte design, and additives that enable fast ion shuttling and stable electrode/electrolyte interfaces, as well as realization of new battery chemistry. Battery chemistry based on monovalent cation, multivalent cation, anion, and dual‐ion transfer is covered. This Review aims to promote the understanding of halide‐based materials to stimulate further research and development in the area of high‐performance rechargeable batteries. It also offers a perspective on the exploration of new materials and systems for electrochemical energy storage.     

From Lithium‐Ion to Sodium‐Ion Batteries: Advantages,Challenges, and Surprises

Mobile and stationary energy storage by rechargeable batteries is a topic of broad societal and economical relevance. Lithium‐ion battery (LIB) technology is at the forefront of the development, but a massively growing market will likely put severe pressure on resources and supply chains. Recently, sodium‐ion batteries (SIBs) have been reconsidered with the aim of providing a lower‐cost alternative that is less susceptible to resource and supply risks. On paper, the replacement of lithium by sodium in a battery seems straightforward at first, but unpredictable surprises are often found in practice. What happens when replacing lithium by sodium in electrode reactions? This review provides a state‐of‐the art overview on the redox behavior of materials when used as electrodes in lithium‐ion and sodium‐ion batteries, respectively. Advantages and challenges related to the use of sodium instead of lithium are discussed.     

Polyanionic Compounds for Potassium‐Ion Batteries

Lithium‐ion batteries have the highest energy density among practical secondary batteries and are widely used for electronic devices, electric vehicles, and even stationary energy‐storage systems. Along with the expansion of demand and applications, the concern about resources of lithium and cobalt is growing. Therefore, secondary batteries composed of abundant elements are required to complement lithium‐ion batteries. In recent years, the development of potassium‐ion batteries has attracted much attention, especially for large‐scale energy storage. In order to realize potassium‐ion batteries, various compounds are proposed and investigated as positive electrode materials, including layered transition‐metal oxides, Prussian blue analogues, and polyanionic compounds. This article offers a review of polyanionic compounds which are typically composed of abundant elements and expected high operating potential. Furthermore, we deliver our new results to partially compensate for lack of studies and provide a future perspective.     

Rocking‐Chair Ammonium‐Ion Battery: A Highly Reversible Aqueous Energy Storage System

Aqueous rechargeable batteries are promising solutions for large‐scale energy storage. Such batteries have the merit of low cost, innate safety, and environmental friendliness. To date, most known aqueous ion batteries employ metal cation charge carriers. Here, we report the first “rocking‐chair” NH₄‐ion battery of the full‐cell configuration by employing an ammonium Prussian white analogue, (NH₄)_1.47Ni[Fe(CN)₆]_0.88, as the cathode, an organic solid, 3,4,9,10‐perylenetetracarboxylic diimide (PTCDI), as the anode, and 1.0 m aqueous (NH₄)₂SO₄ as the electrolyte. This novel aqueous ammonium‐ion battery demonstrates encouraging electrochemical performance: an average operation voltage of ca. 1.0 V, an attractive energy density of ca. 43 Wh kg⁻¹ based on both electrodes’ active mass, and excellent cycle life over 1000 cycles with 67 % capacity retention. Importantly, the topochemistry results of NH₄⁺ in these electrodes point to a new paradigm of NH₄⁺‐based energy storage.     

A Porphyrin Complex as a Self‐Conditioned Electrode Material for High‐Performance Energy Storage

The novel functionalized porphyrin [5,15‐bis(ethynyl)‐10,20‐diphenylporphinato]copper(II) (CuDEPP) was used as electrodes for rechargeable energy‐storage systems with an extraordinary combination of storage capacity, rate capability, and cycling stability. The ability of CuDEPP to serve as an electron donor or acceptor supports various energy‐storage applications. Combined with a lithium negative electrode, the CuDEPP electrode exhibited a long cycle life of several thousand cycles and fast charge–discharge rates up to 53 C and a specific energy density of 345 Wh kg⁻¹ at a specific power density of 29 kW kg⁻¹. Coupled with a graphite cathode, the CuDEPP anode delivered a specific power density of 14 kW kg⁻¹. Whereas the capacity is in the range of that of ordinary lithium‐ion batteries, the CuDEPP electrode has a power density in the range of that of supercapacitors, thus opening a pathway toward new organic electrodes with excellent rate capability and cyclic stability.     

Recent Development of Polyolefin‐Based Microporous Separators for Li−Ion Batteries: A Review

Secondary Li?ion batteries have been paid attention to wide‐range applications of power source for the portable electronics, electric vehicle, and electric storage reservoir. Generally, lithium‐ion batteries are comprised of four components including anode, cathode, electrolyte and separator. Although separators do not take part in the electrochemical reactions in a lithium‐ion (Li?ion) battery, they conduct the critical functions of physically separating the positive and negative electrodes to prevent electrical short circuit while permitting the free flow of lithium ions through the liquid electrolyte that fill in their open porous structure. Hence, the separator is directly related to the safety and the power performance of the battery. Among a number of separators developed thus far, polyethylene (PE) and polypropylene (PP) porous membrane separators have been the most dominant ones for commercial Li?ion batteries over the decades because of their superior properties such as cost‐efficiency, good mechanical strength and pore structure, electrochemical stability, and thermal shutdown properties. However, there are main issues for vehicular storage, such as nonpolarity, low surface energy and poor thermal stability, although the polyolefin separators have proven dependable in portable applications. Hence, in this review, we decide to provide an overview of the types of polyolefin microporous separators utilized in Li?ion batteries and the methods employed to modify their surface in detail. The remarkable results demonstrate that extraordinary properties can be exhibited by mono‐ and multilayer polyolefin separators if they are modified using suitable methods and materials.     

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.     

Reducing the Charge Carrier Transport Barrier in Functionally Layer‐Graded Electrodes

Lithium‐ion batteries (LIBs) are primary energy storage devices to power consumer electronics and electric vehicles, but their capacity is dramatically decreased at ultrahigh charging/discharging rates. This mainly originates from a high Li‐ion/electron transport barrier within a traditional electrode, resulting in reaction polarization issues. To address this limitation, a functionally layer‐graded electrode was designed and fabricated to decrease the charge carrier transport barrier within the electrode. As a proof‐of‐concept, functionally layer‐graded electrodes composing of TiO₂(B) and reduced graphene oxide (RGO) exhibit a remarkable capacity of 128 mAh g⁻¹ at a high charging/discharging rate of 20 C (6.7 A g⁻¹), which is much higher than that of a traditionally homogeneous electrode (74 mAh g⁻¹) with the same composition. This is evidenced by the improvement of effective Li ion diffusivity as well as electronic conductivity in the functionally layer‐graded electrodes.     

磷酸钒钠Na_3V_2(PO_4)_3电化学储能研究进展

锂离子电池在全球范围内的广泛应用加剧了对锂资源的消耗,其成本和原料将限制其未来发展。钠与锂具有相似物理化学性质,并且储量丰富。根据锂离子"摇椅式"电池原理,富钠离子化合物可类似富锂离子正极材料,提供可脱嵌的钠离子及结构。钠离子较锂离子大,其可逆脱嵌反应要求材料结构具有较大的容钠位与离子迁移通道。聚阴离子体磷酸钒钠Na_3V_2(PO_4)_3属于钠离子超导体(NASICON)材料,其NASICON结构骨架形成了稳定的容钠位,并且开放的三维离子迁移通道利于提高钠离子的扩散。Na_3V_2(PO_4)_3作为电池正极材料,具有理想的比容量、电压平台与循环稳定性,从而受到了广泛关注。本文首先介绍了Na_3V_2(PO_4)_3结构特点,其次结合团队已有的工作基础对Na_3V_2(PO_4)_3在钠离子电池、混合离子电池、水系电池,混合超级电容器等体系中的应用与反应机理进行了阐述;总结了基于Na_3V_2(PO_4)_3设计的复合材料与结构并探讨了Na_3V_2(PO_4)_3可能存在的问题与未来发展趋势。     

Sustainable Electrical Energy Storage through the Ferrocene/Ferrocenium Redox Reaction in Aprotic Electrolyte

The large‐scale, cost‐effective storage of electrical energy obtained from the growing deployment of wind and solar power is critically needed for the integration into the grid of these renewable energy sources. Rechargeable batteries having a redox‐flow cathode represent a viable solution for either a Li‐ion or a Na‐ion battery provided a suitable low‐cost redox molecule soluble in an aprotic electrolyte can be identified that is stable for repeated cycling and does not cross the separator membrane to the anode. Here we demonstrate an environmentally friendly, low‐cost ferrocene/ferrocenium molecular redox couple that shows about 95 % energy efficiency and about 90 % capacity retention after 250 full charge/discharge cycles.     

室温钠离子储能电池电极材料结构研究进展

随着风能和太阳能等新能源的大规模发展及未来智能电网的实现,大规模储能系统显得越来越重要.室温钠离子电池以较低的成本再次引起了研究者的兴趣,并成为一种有前途、低成本的储能体系.目前,已提出多种材料可作为钠离子电池的电极材料.一般而言,材料的性质主要由材料的晶体结构决定,本文主要介绍目前提出的多种可行室温钠离子电池电极材料的晶体结构,希望通过总结已有电极材料的晶体结构,对新材料的设计提供指导.     

An Electrolytic Zn–MnO2 Battery for High‐Voltage and Scalable Energy Storage

Zinc‐based electrochemistry is attracting significant attention for practical energy storage owing to its uniqueness in terms of low cost and high safety. However, the grid‐scale application is plagued by limited output voltage and inadequate energy density when compared with more conventional Li‐ion batteries. Herein, we propose a latent high‐voltage MnO₂ electrolysis process in a conventional Zn‐ion battery, and report a new electrolytic Zn–MnO₂ system, via enabled proton and electron dynamics, that maximizes the electrolysis process. Compared with other Zn‐based electrochemical devices, this new electrolytic Zn–MnO₂ battery has a record‐high output voltage of 1.95 V and an imposing gravimetric capacity of about 570 mAh g^?1, together with a record energy density of approximately 409 Wh kg^?1 when both anode and cathode active materials are taken into consideration. The cost was conservatively estimated at <US$ 10 per kWh. This result opens a new opportunity for the development of Zn‐based batteries, and should be of immediate benefit for low‐cost practical energy storage and grid‐scale applications.     

A Universal Organic Cathode for Ultrafast Lithium and Multivalent Metal Batteries

Low‐cost multivalent battery chemistries (Mg²⁺, Al³⁺) have been extensively investigated for large‐scale energy storage applications. However, their commercialization is plagued by the poor power density and cycle life of cathodes. A universal polyimides@CNT (PI@CNT) cathode is now presented that can reversibly store various cations with different valences (Li⁺, Mg²⁺, Al³⁺) at an extremely fast rate. The ion‐coordination charge storage mechanism of PI@CNT is systemically investigated. Full cells using PI@CNT cathodes and corresponding metal anodes exhibit long cycle life (>10000 cycles), fast kinetics (>20 C), and wide operating temperature range (?40 to 50 °C), making the low‐cost industrial polyimides universal cathodes for different multivalent metal batteries. The stable ion‐coordinated mechanism opens a new foundation for the development of high‐energy and high‐power multivalent batteries.     

High‐Capacity Anode Materials for Sodium‐Ion Batteries

Na‐ion batteries are an attractive alternative to Li‐ion batteries for large‐scale energy storage systems because of their low cost and the abundant Na resources. This Review provides a comprehensive overview of selected anode materials with high reversible capacities that can increase the energy density of Na‐ion batteries. Moreover, we discuss the reaction and failure mechanisms of those anode materials with a view to suggesting promising strategies for improving their electrochemical performance.     

High‐Performance Sodium‐Ion Batteries and Sodium‐Ion Pseudocapacitors Based on MoS2/Graphene Composites

Sodium‐ion energy storage, including sodium‐ion batteries (NIBs) and electrochemical capacitive storage (NICs), is considered as a promising alternative to lithium‐ion energy storage. It is an intriguing prospect, especially for large‐scale applications, owing to its low cost and abundance. MoS₂ sodiation/desodiation with Na ions is based on the conversion reaction, which is not only able to deliver higher capacity than the intercalation reaction, but can also be applied in capacitive storage owing to its typically sloping charge/discharge curves. Here, NIBs and NICs based on a graphene composite (MoS₂/G) were constructed. The enlarged d‐spacing, a contribution of the graphene matrix, and the unique properties of the MoS₂/G substantially optimize Na storage behavior, by accommodating large volume changes and facilitating fast ion diffusion. MoS₂/G exhibits a stable capacity of approximately 350 mAh g^?1 over 200 cycles at 0.25 C in half cells, and delivers a capacitance of 50 F g^?1 over 2000 cycles at 1.5 C in pseudocapacitors with a wide voltage window of 0.1–2.5 V.     

Interfacial Design of Dendrite‐Free Zinc Anodes for Aqueous Zinc‐Ion Batteries

Aqueous zinc‐ion batteries have rapidly developed recently as promising energy storage devices in large‐scale energy storage systems owing to their low cost and high safety. Research on suppressing zinc dendrite growth has meanwhile attracted widespread attention to improve the lifespan and reversibility of batteries. Herein, design methods for dendrite‐free zinc anodes and their internal mechanisms are reviewed from the perspective of optimizing the host–zinc interface and the zinc–electrolyte interface. Furthermore, a design strategy is proposed to homogenize zinc deposition by regulating the interfacial electric field and ion distribution during zinc nucleation and growth. This Minireview can offer potential directions for the rational design of dendrite‐free zinc anodes employed in aqueous zinc‐ion batteries.     

Ti3C2Tx MXene compounds for electrochemical energy storage

Since their discovery in 2011, MXene compounds, and in particular the Ti₃C₂-based phases, have gained increasing interest from researchers leading to over 2000 scientific works in 2020. The peculiar morphological, charge transport, and surface properties make the MXenes ideal materials for energy storage applications such as active material in alkaline ion batteries and supercapacitors, as conductive or buffer agent in composite electrodes for high energy applications, and as electrocatalytic materials for oxygen evolution or redox flow batteries. Among this almost endless literature, this work focuses on 5 recent articles (2019/2020) that summarize the potential of MXenes in different energy storage applications, also resuming the most promising preparatory routes regarding industrial scalability.     

Tailoring A Poly(ether sulfone) Bipolar Membrane: Osmotic‐Energy Generator with High Power Density

Osmotic energy, obtained through different concentrations of salt solutions, is recognized as a form of a sustainable energy source. In the past years, membranes derived from asymmetric aromatic compounds have attracted attention because of their low cost and high performance in osmotic energy conversion. The membrane formation process, charging state, functional groups, membrane thickness, and the ion‐exchange capacity of the membrane could affect the power generation performance. Among asymmetric membranes, a bipolar membrane could largely promote the ion transport. Here, two polymers with the same poly(ether sulfone) main chain but opposite charges were synthesized to prepare bipolar membranes by a nonsolvent‐induced phase separation (NIPS) and spin‐coating (SC) method. The maximum power density of the bipolar membrane reaches about 6.2 W m^?2 under a 50‐fold salinity gradient, and this result can serve as a reference for the design of bipolar membranes for osmotic energy conversion systems.