Ideal Energy Storage Devices Research Articles

Interfacial post-heterojunction construction in Mn-doped NiS2 for realizing fast and stable sodium storage

Sodium-ion batteries (SIBs) are considered as ideal energy storage devices. However, sluggish kinetics and mechanical instability of electrode materials hinder the development of SIBs in practical application. It is necessary to design a high-performance anode material for fast and stable sodium storage. Herein, Mn-doped NiS2 with a post-heterojunction (M−NS/C-2) is prepared. The electrochemical performance is improved by the synergistic effect of Mn-doping and post-heterojunction interface construction. On the one hand, Mn-doping enlarges the lattice spacing of NiS2 to accommodate sodium ions, moreover, the stacked morphology with interlamellar void influenced by doping provides a structural buffer and dominant pseudo-capacity. On the other hand, Cu7.2S4 is formed in ether electrolyte for the reaction of polysulfide and copper current collector, which grafts active material onto the copper current collector, reinforcing mechanical supporting. Further, the post-heterojunction interface formation between NiS2 and Cu7.2S4 in the cyclic process can be promoted by Mn-doping, boosting electron transfer to facilitate rapid kinetics. Thus, M−NS/C-2 displays good rate performance (497.9 mAh/g even at 10 A/g) and superior cycling stability (390.4 mAh/g after 20,000 cycles at 10 A/g with 0.0013 % attenuation per cycle). The M−NS/C-2|| Na3V2(PO4)3 full cell shows cyclic performance of 241.5 mAh/g after 100 cycles at 1 A/g.

Electrochemical Investigation of ZnS/NiO Nanocomposite based Symmetric Supercapattery

AbstractSupercapattery is an ideal energy storage device combining the features of supercapacitors and batteries, offers a high‐energy density as well as high‐power density with extended operational lifespan. In this work, zinc sulfide (ZnS) and zinc sulfide/nickel oxide (ZnS/NiO) nanocomposite was synthesized via chemical coprecipitation method and characterized using state‐of‐the‐art analytical tools. The ZnS/NiO electrode exhibited remarkable electrochemical performance as an electrode material than pure ZnS. The ZnS/NiO nanocomposite exhibited high crystallinity, and spherical nanoparticles with an average grain size of 20–40 nm having a homogeneous dispersion. The ZnS/NiO electrode exhibited an ultrahigh specific capacity of 1803.87 Cg−1 at a relatively low scan rate of 10 mVs−1 in a 1 M KOH solution from cyclic voltammetry and 393 Cg−1 at 16 Ag−1 from charge discharge measurements, and it showed exceptional cycling stability (98 % capacity retention after 1000 cycles). Furthermore, the ZnS/NiO symmetric supercapattery device exhibited 44.43 Fg−1 specific capacitance, 5.52 Wh kg−1 energy density, and 1600 Wkg−1 power density at current density of 0.8 Ag−1 in 1 M KOH solution from galvanostatic charge discharge. After 3000 cycles, the ZnS/NiO nanomaterial demonstrated promising cyclic stability of 95 %. The ZnS/NiO supercapattery nanocomposite might be considered as a potential hybrid electrode material for the future development of electrochemical energy storage devices.

Construction of CNT/CuS/FeOOH hierarchical composites on carbon cloth for high-performance solid-state flexible supercapacitors

Flexible supercapacitors (FSC) are ideal energy storage devices for wearable electronic products, yet longstanding constrained by the limited performance of negative materials. Rational design of multiple-component nanocomposites with hierarchical structures is an effective strategy to enhance the energy storage capacity. In this study, a high-capacitance flexible electrode was constructed through the in-situ growth of copper sulfide (CuS) nanosheets on carbon nanotubes (CNT) decorated carbon cloth (CC), followed by the electrodeposition of ferric hydroxide (FeOOH). The negative electrode (CC/CNT/CuS/FeOOH) demonstrates an exceptional areal capacitance of 1956.1 mF cm−2 at 1 mA cm−2 and excellent cycle stability. Subsequently, a corresponding FSC device was constructed by incorporating NiCo layered double hydroxide (CC/CNT/NiCo-LDH) as the positive material and KOH/polyvinyl alcohol (PVA) gel as the electrolyte. The FSC device exhibits an impressive volumetric energy density of 3.3 Wh cm−3 under the power density of 12.2 W cm−3. It also demonstrates excellent electrochemical and mechanical stability, showcasing high capacitance retention under cyclic use and bending conditions. This work presents a rational design strategy for the development of cost-effective, high-capacitance and stable flexible electrodes, which holds promising for integration into wearable electronic devices.

Challenges and outlook for lithium-ion battery fault diagnosis methods from the laboratory to real world applications

Lithium-ion batteries are the ideal energy storage device for numerous portable and energy storage applications. Efficient fault diagnosis methods become urgent to address safety risks. The fault modes, fault data, fault diagnosis methods in different scenarios, i.e., laboratory, electric vehicle, energy storage system, and simulation, are reviewed and compared comprehensively. The data characteristics, performance and limitations of fault diagnosis methods are discussed further. The results show that the fault diagnosis methods of laboratory scenario are more advanced than real-world applications because of the clean and perfect dataset, advanced equipment, and ideal operating conditions. At last, the outlook and challenges for applying fault diagnosis methods from laboratory to real-world applications are investigated from three aspects: unified framework of fault diagnosis methods, cloud big data fusion, and application of laboratory measurement technologies. To realize more accurate fault diagnosis in real-world applications within the advanced research of laboratory, more significant work is still needed.

Wide-Potential-Window Bimetallic Hydrated Eutectic Electrolytes with High-Temperature Resistance for Zinc-Ion Hybrid Capacitors.

Aqueous zinc-ion hybrid capacitors (ZHCs) are considered ideal energy-storage devices. However, the common aqueous Zn2+ -containing electrolytes used in ZHCs often cause parasitic reactions during charging-discharging owing to free water molecules. Hydrated eutectic electrolytes (HEEs) that bind water molecules through solvation shells and hydrogen bonds can be applied at high temperatures and within a wide potential window. This study reports a novel bimetallic HEE (ZnK-HEE), consisting of zinc chloride, potassium chloride, ethylene glycol, and water, which enhances the capacity and electrochemical reaction kinetics of ZHCs. The bimetallic solvation shell in ZnK-HEE is studied by molecular dynamics and density functional theory, confirming its low step-by-step desolvation energy. A Zn//activated carbon ZHC in ZnK-HEE shows a high operating voltage of 2.1 V, along with an ultrahigh capacity of 326.9 mAh g-1 , power density of 2099.7 W kg-1 , and energy density of 343.2 Wh kg-1 at 100°C. The reaction mechanisms of charging-discharging process are investigated by ex situ X-ray diffraction. This study reports a promising electrolyte for high-performance ZHCs, which exhibits high-temperature resistance and is operable within a wide potential window.

A bibliometric analysis of lithium-ion batteries in electric vehicles

As the ideal energy storage device, lithium-ion batteries (LIBs) are already equipped in millions of electric vehicles (EVs). The complexity of this system leads to the related research involving all aspects of LIBs and EVs. Therefore, the research hotspots and future research directions of LIBs in EVs deserve in-depth study. A bibliometric analysis is conducted according to the SCI-Expanded database in the Web of Science Core Collection. From 1993 to 2022, a total of 5187 articles or review articles related to LIBs and EVs have been published. The visualization means of geographical tool, software VOSviewer and CiteSpace help to visualize the structure network. The annual publications, countries, institutions, authors, terms, and references of the retrieved publications and the relation between them are analyzed comprehensively. This paper quantitatively analyzes the development tendency of LIBs in EVs, which provides experienced reference for researchers who want to engage in this domain.

Flexible quasi-3D zinc ion microcapacitor based on V2O5-PANI cathode and MXene anode

Zinc ion microcapacitors (ZIMCs) are ideal energy storage device candidates for wearable electronic devices based on the matching between battery-type electrodes and capacitor-type electrodes, making full use of the respective advantages of batteries and capacitors. Herein, three-dimensional (3D) networked reduced graphene oxide- aramid nanofiber (rGO-ANF) foams were prepared by gas foaming technology and a laser engraving process. This process is not only simple and facile, but also involves inexpensive equipment, and meets the requirements for large-scale industrial production. Moreover, rGO-ANF foam exhibits good mechanical properties and generates numerous pores in the same direction as the electrolyte transport pathway during foaming. Using this rGO-ANF foam as a substrate, MXene as capacitor-type electrode, and vanadium oxide-polyaniline composite as battery-type electrode, a ZIMC with both high mechanical properties and high energy storage capacity, was successfully prepared in this study. This ZIMC shows excellent capacitance density (584 mF⋅cm−2 at 0.4 mA⋅cm−2) and energy density (262.8 μWh⋅cm−2, 360.3 μW⋅cm−2). Furthermore, the integrated pressure sensing system built on this ZIMC could monitor human physiological signals in real time with high accuracy, sensitivity, and fast response, demonstrating the feasibility of building ZIMCs as functional devices in wearable electronic devices. This new ZIMC exhibits significant potential for future wearable electronic devices.

Self-supported graphene oxide encapsulated chalcopyrite electrode for high-performance Li-ion capacitor

The combination of lithium-ion batteries and supercapacitors makes lithium-ion capacitors (LICs) the ideal energy storage device for commercial applications. However, the high performance of LICs is restricted due to various shortcomings such as low electrode specific capacity and sluggish reaction kinetics. Additionally, the undesirable ‘polysulfide-diffusion’ effect in the cost-effective metal sulfide-based electrodes results in high capacity degradation. Therefore, developing novel strategies to surmount these drawbacks is of prime importance for the development of high-performance LICs. Herein, a novel composite material with the unique architecture of graphene oxide (GO) encapsulation on the chalcopyrite (CuFeS2) microspheres is fabricated as an anode for LIC. Compared to the traditional binder-based approach for electrode fabrication, the anode is fabricated using a ‘binder-free’ approach to enable the exposure of high-density electroactive sites. As a result, the fabrication of a ‘self-standing’ flexible electrode is obtained that finds numerous applications in wearable technology systems. Detailed electrochemical analysis reveals the enhanced reaction kinetics of the composite electrode along with the improved specific capacities and rate capabilities. The unique architecture of the GO encapsulation not only prevents the structural collapse of the chalcopyrite microspheres but also suppresses the polysulfide diffusion, resulting in higher cyclic stability. The role of such carbon encapsulation is studied in detail using experimental studies and is strongly supported by theoretical calculations based on density functional theory (DFT) for the first time. The calculated binding energy and charge transfer confirmed the improved interactive features of Li ions with the composite electrode in terms of enhanced binding energy and higher valence charge transfer. Additionally, the favorable binding energy of Li2S and Li2S4 polysulfides to the composite electrode than the pristine CFS electrode reflects restricted polysulfide diffusion, resulting in outstanding cyclic stability. The assembled LIC device based on the composite electrode displays a large energy density of 192.33 Wh/kg, a high power density of 14,280 W/kg, and excellent cyclic stability of >90 % for 10,000 cycles, outperforming most of the reported metal sulfide-based LICs.

Health-aware multi-stage charging strategy for lithium-ion batteries based on whale optimization algorithm

Lithium-ion batteries are widely used in electronics, new energy electric vehicles and energy storage plants. They have become ideal energy storage devices for their excellent characteristics of high energy density, low self-discharge rate, low carbon and environmental protection. Thus, research on lithium-ion batteries has wide scientific and engineering significance. To promote the application of lithium-ion batteries, the charging speed and aging rate of the lithium-ion batteries should be optimized to improve the convenience and economics for using them. Therefore, in this paper, a health-aware multi-stage charging strategy is presented based on the whale optimization algorithm. Specifically, the electrical model, thermal model, and the semi-empirical aging model are established firstly. Then the multi-stage charging optimization strategy considering charging time and battery health loss is proposed. The whale optimization algorithm is presented to obtain the optimal current value at each stage, followed by exploring the factors affecting the charging performance which include fitness function weight, cut-off voltage and current stage number. Compared with constant current (CC) charging, the total fitness function loss decreased by 34.64%, and the charging time decreased by 11.45%. This paper provides audiences with a strategy to meet the trade-off between charging rapidity and battery life in different scenarios by setting the optimization weights.

Translational materials research - From laboratory to product: A 1200 F cylindrical supercapacitor from petroleum coke derived activated carbon sheets

Cylindrical supercapacitors are ideal energy storage devices for electric vehicle applications because of their safety, high power, and capacitance. In this regard, synthesis and utilization of activated carbon materials in supercapacitors for commercial usage is the need of the hour. Many researchers have reported the synthesis of carbon-based materials for supercapacitor application. However, the studies and application of such materials are limited to laboratory coin-cell level testing. In this work, for the first time, we have not only synthesized activated carbon sheets with a surface area of 2394 m2/g from petroleum coke but also demonstrated the commercial applicability of petroleum coke derived activated carbon sheets by fabricating a cylindrical supercapacitor with the specifications of 2.7 V and 1200 F, and the dimension of (60 × 80 mm) (D × H). The cylindrical supercapacitor exhibited a high capacitance of 1202 F with a stored energy of 1.22 Wh and a gravimetric energy density of 5.05 Wh/Kg. Also, the indigenous cylindrical device was diffusely compared with a commercially available supercapacitor of similar size, and the fabricated supercapacitor in this work reveals a great potential in terms of promising electrochemical properties for commercial applicability. The results also demonstrate that the petroleum coke carbon-based supercapacitor developed in this work can be used as an alternative to the commercial coconut charcoal carbon-based supercapacitor due to the inexpensive petroleum coke with rich carbon content.

Ultrasoft all-hydrogel aqueous lithium-ion battery with a coaxial fiber structure

Fiber batteries have been developed as ideal energy storage devices for wearable electronics due to their superior miniaturization, deformability, and flexibility compared with conventional bulk and thin-film batteries. However, currently reported fiber batteries use materials that are intrinsically rigid or have limited flexibility (e.g., metal, carbon materials, and elastomers), which potentially cause physical irritation and internal injury upon close contact with biological tissues. Therefore, it is necessary to design soft materials for ultrasoft fiber batteries that are mechanically matched with biological tissues. Here, ultrasoft coaxial fiber-structured aqueous lithium-ion batteries based on an all-hydrogel design are reported. The all-hydrogel fiber aqueous lithium-ion batteries exhibited a low Young’s modulus of 445 kPa, which perfectly matched that of biological tissue. They also showed a high specific discharge capacity of 84.8 mAh·g−1 at a current density of 0.5 A·g−1 and superior performance in terms of cycling behavior and rate capacity. Furthermore, these fiber batteries maintained stable electrochemical performance while undergoing different complex deformations. The present work demonstrates a paradigm for designing ultrasoft fiber batteries and also provides insight into the development of soft wearable electronics.

Critical review of life cycle assessment of lithium-ion batteries for electric vehicles: A lifespan perspective

Lithium-ion batteries (LIBs) are the ideal energy storage device for electric vehicles, and their environmental, economic, and resource risks assessment are urgent issues. Therefore, the life cycle assessment (LCA) of LIBs in the entire lifespan is becoming a hotspot. This study first reviews the basic framework and types, standards and methods, and technical challenges of LCA. Then, the cradle-to-cradle LCA framework for LIBs is constructed, and the technical route of LCA in the stages of battery production, usage, secondary utilization, and material recycling are analyzed in detail. Finally, the carbon footprint in the battery production and recycling stages is conducted under the current and future energy mixes. The results show that battery production significantly impacts the environment and resources, and battery materials recycling and remanufacturing present considerable environmental and economic values. Moreover, the greening of electricity is critical to reducing carbon emissions during the battery life cycle. • The framework, methods, and technical challenges of LCA are comprehensively reviewed. • The cradle-to-cradle LCA framework for lithium-ion batteries is constructed. • Carbon emissions during battery production and recycling are analyzed. • Carbon emissions during battery production under different energy mixes are investigated.

Synthesis of K[B3H7NH2BH2NH2B3H7] for a K-ion solid-state electrolyte.

All-solid-state K batteries are ideal energy storage devices for grid-scale applications of renewable energies. A novel electrolyte K[B3H7NH2BH2NH2B3H7] with weakly coordinating anions was synthesized. It has a high K+ conductivity of 1.01 × 10-4 S cm-1 at 75 °C, which is probably due to the increased electrostatic potential and size of the anions.

An organic bifunctional redox active material for symmetric aqueous redox flow battery

Symmetric redox flow batteries utilizing a single redox active material as catholyte and anolyte, offer a plausible and unique strategy to alleviate cross-contamination issues during cycling, making them an ideal energy storage device for large scale applications. In this work, a low-cost riboflavin organic molecule is coupled with a 2,2,6,6-Tetramethylpiperidinyl-N-oxyl (TEMPO) radical molecule to form a single Riboflavin-TEMPO (RIBOTEMPO) bifunctional redox active material, which is used in both aqueous anolyte and catholyte. Cyclic voltammetry analysis of the combined molecule displays electrochemically reversible reactions for the redox couples at −0.72 V and 0.51 V versus Hg/Hg 2 SO 4 , leading to a theoretical cell voltage of 1.23 V. A symmetric cell testing demonstrated over 100 consecutive charge/discharge cycles with nearly 80% coulombic efficiency and capacity retention of 44.7% at a current density of 2.5 mA cm −2 . By utilizing a pH neutral supporting electrolyte, a low-cost, safe, and environmental-friendly redox flow battery is achieved. This work provides a pathway for the design and development of bifunctional redox active molecules for symmetric battery applications. • A bifunctional organic redox active material is designed and synthesized. • The battery displayed a high cell voltage of 1.23 V. • Molecule degradation is identified as the main cause of capacity loss.

Smart power system of biocompatible and flexible micro-supercapacitor

Flexible micro-supercapacitor (MSC) is an ideal energy storage device for flexible and small-scale electronics, specifically some human health sensors, because of its flexibility, long working life, high power density, and high charge and discharge rate. In this work, a smart power system of MSC is developed. First, utilizing ink-jet printing and electrochemical deposition, flexible MSC is fabricated on the biocompatible substrate of a modified silk protein film, making the power system suitable for implantable devices. Second, aiming at the common drawbacks of small energy density and large voltage variation of MSC, a wireless charging component and a wireless inductor–capacitor (LC) voltage sensor are integrated with the MSC unit. Using pulse charging mode, charging and voltage detection can be performed at the same time. The LC voltage sensor, using varactor diodes to realize voltage capacitance mapping, does not need extra ICs or consume any energy. Such a system has great application potential as the energy supply part of small devices implanted in the human body.

Ni3Si2@TiO2 furs for supercapacitors with extremely high areal density and high cycleability

Supercapacitors with high energy density, fast charging/discharging rate, and long cycle life are ideal energy storage devices. A sufficient amount of the electrode materials is important to obtain high energy density supercapacitors. The poor electronic and ionic conductivity are accompanying with increasing amount of electrode materials, which hinder the energy density and capacitance retention of supercapacitors especially under high current densities. Long Ni3Si2 nanoarrays with higher areal density and larger exposed surface areas have been in situ grown on Ni foams as Ni3Si2 furs by low pressure chemical vapor deposition to give sufficient amount of electrode materials with high electronic and ionic conductivity. Atomic layer deposition process has then been adopted to coat the Ni3Si2 nanowires with different thick TiO2, yielding Ni3Si2@TiO2 furs. The Ni3Si2@TiO2 furs with 1 nm TiO2 coating have been demonstrated to have high supercapacitor performance. An extremely high specific capacitance as high as 7.82 F cm−2 has been achieved by Ni3Si2@TiO2-1nm furs at a current density of 5 mA cm−2. A high areal capacitance of 5.91 F cm−2 and an excellent cycling stability of 95.6% retention after 5000 cycles at a high current density of 100 mA cm−2 have been obtained. The asymmetric supercapacitor assembled with Ni3Si2@TiO2-1nm exhibits volumetric energy density of 1.528 mWh cm−3 at a power density of 25 mW cm−3 and 0.93 mWh cm−3 at 0.1 W cm−3.

Solid-state-grinding method to synthesize NiCoFe alloy/NiCoFe–OH nanosheets for asymmetric supercapacitor

Solid-state-grinding is a facile method to prepare electrode materials, which is more beneficial to large-scale production. Herein, 3D NiCoFe alloy framework covered with NiCoFe–OH nanosheets hybrid architecture is constructed via solid-state-grinding and subsequent glycerol solvothermal treatment. Highly conductive NiCoFe alloy core stimulates its fast and charged transport, and as a result, high-capacity NiCoFe–OH nanosheets with rich active sites could participate into rapid electrochemical phase variation with KOH electrolyte. Moreover, the abundance of existing interfaces between the NiCoFe and NiCoFe–OH structures produces more electrochemical activity and presents further improvement to the electrical conductivity, both of which greatly regulate the electrochemical performance of electrode materials. NiCoFe/NiCoFe–OH//active carbon (AC) asymmetric supercapacitor (ASC) was assembled, showing a specific capacitance of 106 F g−1 at 1 A g−1, 36% of capacitance retention at 10 A g−1 and 37.4 Wh kg−1 of energy density at 756.4 W kg−1 of power density. The most noteworthy is its excellent cycling stability, 89.3% of capacitance retention after 20,000 cycles. The simple and large-scale preparation method, high energy and power densities, and long cycling stability make NiCoFe/NiCoFe–OH//AC ASC an ideal energy storage device for driving LED bulbs and electronics, etc., as well as being able to charge/discharge repeatedly.

A materials perspective on magnesium-ion-based solid-state electrolytes

As economically viable alternatives to lithium-ion batteries, magnesium-ion-based all-solid-state batteries have been researched to meet the criteria for an ideal energy storage device.

Design of 2D Self-Supported Hybrid CuSe@PANI Core/Shell Nanosheet Arrays for High-Performance Flexible Microsupercapacitors

All-solid-state micro-supercapacitors (MSCs) are ideal energy storage devices for fast-growing and high-integrated small electronic devices. In this paper, 2D self-supported hybrid CuSe@PANI core/s...

Preparation of pyridine N-doped metal-free Li–O2 battery cathode by one-step

Lithium-oxygen (Li–O2) batteries are an ideal energy storage device, but the problems of the cathode still hinder their development. In this work, a metal-free, binder-free and in situ pyridine N-doped cathode of Li–O2 batteries is synthesized in one step by electrospinning. Meanwhile, the effect of carbonization temperature on cathode is discussed in detail. The content of pyridine N in the cathode is the highest at the carbonization temperature of 700 °C, and it is also the most effective for the reversible formation and decomposition of Li2O2. In terms of Li–O2 batteries performance, when the charge and discharge current density is 100 mA g−1 and the discharge voltage is greater than 2 V, the discharge specific capacity and discharge capacity can reach 27900 mAh g−1 and 27.9 mAh respectively. In addition, when the limited specific capacity is 1000 mAh g−1, the batteries can work stably for 85 cycles under the same conditions. Therefore, the high-performance cathode which synthesized in one step by electrospinning is expected to promote the commercial application of Li–O2 batteries.