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Abstract: Designing an optimum cell configuration that can deliver high capacity, fast charge–discharge capability, and good cycle retention is imperative for developing a high‐performance lithium–sulfur battery. Herein, a novel lithium–sulfur cell design is proposed, which consists of sulfur and magnesium–aluminum‐layered double hydroxides (MgAl‐LDH)–carbon nanotubes (CNTs) composite cathode with a modified polymer separator produced by dual side coating approaches (one side: graphene and the other side: aluminum oxides). The composite cathode functions as a combined electrocatalyst and polysulfide scavenger, greatly improving the reaction kinetics and stabilizing the Coulombic efficiency upon cycling. The modified separator enhances further Li+‐ion or electron transport and prevents undesirable contact between the cathode and dendritic lithium on the anode. The proposed lithium–sulfur cell fabricated with the as‐prepared composite cathode and modified separator exhibits a high initial discharge capacity of 1375 mA h g−1 at 0.1 C rate, excellent cycling stability during 200 cycles at 1 C rate, and superior rate capability up to 5 C rate, even with high sulfur loading of 4.0 mg cm−2. In addition, the findings that found in postmortem chracterization of cathode, separator, and Li metal anode from cycled cell help in identifying the reason for its subsequent degradation upon cycling in Li–S cells. [ABSTRACT FROM AUTHOR]

A comprehensive study of Na[NixCoyMnz]O2 (x = 1/3, 0.5, 0.6, and 0.8) cathodes is carried out to determine the optimal composition as the electrochemical, structural, and thermal properties of O3-type layered cathodes are strongly dependent on the transition metal composition. Here, the role of each transition metal in [NixCoyMnz]O2 cathodes is identified via electrochemical property characterization, structural analysis, and thermal stability testing. Briefly, an increase of the Ni fraction resulted in an increasingly higher capacity but is accompanied by progressively poor capacity retention. On the other hand, the Co metal played an important role in stabilizing the structure, while the Mn content contributed to enhancing the capacity retention and thermal stability. The present study highlights the importance of appropriately balancing the transition metal composition in a layered Na[NixCoyMnz]O2 cathode. Furthermore, this work provides a design guideline for developing an ideal Na[NixCoyMnz]O2 cathode with both high capacity and optimal cycle retention in addition to thermal stability. [ABSTRACT FROM AUTHOR]

The development of high-energy and high-power density sodium-ion batteries is a great challenge for modern electrochemistry. The main hurdle to wide acceptance of sodium-ion batteries lies in identifying and developing suitable new electrode materials. This study presents a composition-graded cathode with average composition Na[Ni0.61Co0.12Mn0.27]O2, which exhibits excellent performance and stability. In addition to the concentration gradients of the transition metal ions, the cathode is composed of spoke-like nanorods assembled into a spherical superstructure. Individual nanorod particles also possess strong crystallographic texture with respect to the center of the spherical particle. Such morphology allows the spoke-like nanorods to assemble into a compact structure that minimizes its porosity and maximizes its mechanical strength while facilitating Na+-ion transport into the particle interior. Microcompression tests have explicitly verified the mechanical robustness of the composition-graded cathode and single particle electrochemical measurements have demonstrated the electrochemical stability during Na+-ion insertion and extraction at high rates. These structural and morphological features contribute to the delivery of high discharge capacities of 160 mAh (g oxide)−1 at 15 mA g−1 (0.1 C rate) and 130 mAh g−1 at 1500 mA g−1 (10 C rate). The work is a pronounced step forward in the development of new Na ion insertion cathodes with a concentration gradient. [ABSTRACT FROM AUTHOR]

A novel nanocomposite cathode consisting of sulfur and hollow-mesoporous titania (HMT) embedded within carbon nanotubes (CNT), which is designated as S-HMT@CNT, has been obtained by encapsulating elemental sulfur into the pores of hollow-mesoporous, spherical TiO2 particles that are connected via CNT. A carbon-paper interlayer, referred to as dual functional porous carbon wall (DF-PCW), has been obtained by filling the voids in TiO2 spheres with carbon and then etching the TiO2 template with a chemical process. The DF-PCW interlayer provides a medium for scavenging the lithium polysulfides and suppressing them from diffusing to the anode side when it is inserted between the sulfur cathode and the separator. Lithium-sulfur cells fabricated with the thus prepared S-HMT@CNT cathode and the DF-PCW interlayer exhibit superior performance due to the containment of sulfur in TiO2 and improved lithium-ion and electron transports. The Li-S cells display high capacity with excellent capacity retention at rates as high as 1C, 2C, and 5C rates. [ABSTRACT FROM AUTHOR]

Lithium transition metal oxide layers, Li[Ni1−x−yCox(Mn and/or Al)y]O2, are widely used and mass-produced for current rechargeable battery cathodes. Development of cathode materials has focused on increasing the Ni content by simply controlling the chemical composition, but as the Ni content has almost reached its limit, a new breakthrough is required. In this regard, microstructural modification is rapidly emerging as a prospective approach, namely in the production of nano-rod layered cathode materials. A comprehensive review of the physicochemical properties and electrochemical performances of cathodes bearing the nano-rod microstructure is provided herein. A detailed discussion is regarding the structural stability of the cathode, which should be maximized to suppress microcrack formation, the main cause of capacity fading in Ni-rich cathode materials. In addition, the morphological features required to achieve optimal performance are examined. Following a discussion of the initial nano-rod cathodes, which were based on compositional concentration gradients, the preparation of nano-rod cathodes without the inclusion of a concentration gradient is reviewed, highlighting the importance of the precursor. Subsequently, the challenges and advances associated with the nano-rod structure are discussed, including considerations for synthesizing nano-rod cathodes and surface shielding of the nano-rod structure. It goes on to cover nano-rod cathode materials for next-generation batteries (e.g., all-solid-state, lithium-metal, and sodium-ion batteries), inspiring the battery community and other materials scientists looking for clues to the solution of the challenges that they encounter. [ABSTRACT FROM AUTHOR]

"Anodeless" electrodes for all‐solid‐state batteries (ASSBs) have been attracting attention as a solution for achieving high energy density. Recent studies on anodeless electrodes have shown improvements in cycle life and energy density through the stabilization of plated lithium (Li) using Li‐soluble metals (e.g., Ag, Zn, etc.). In this study, magnesium‐based materials (MgF2@C) are introduced for use as an anodeless electrode. Nanodot magnesium fluoride (MgF2) is synthesized onto a carbon black surface via sonochemical synthesis. MgF2 is converted to a Mg‐Li alloy and LiF during lithiation. The Mg‐Li alloy from the MgF2@C anodeless electrode reduces lithiation overpotential and provides a uniform and dense Li layer between the current collector and the anodeless electrode. The ASSB cell assembled with the MgF2@C anodeless electrode exhibits 81.4% capacity retention after 200 cycles at 30 °C. [ABSTRACT FROM AUTHOR]

In article number 2101123 by Yang-Kook Sun, Jaekook Kim, Jang-Yeon Hwang, and co-workers, a new class of sulfur cathodes, sulfurized polyacrylonitrile (SPAN) are summarized, in which active sulfur moieties are covalently bounded to carbon backbone. In particular, this review provides the multiscale understanding of the SPAN cathode in metal-sulfur batteries including the scientific and technological discussions. B Advanced Cathode for Metal-Sulfur Batteries b Metal-sulfur batteries have shown high potential because of their high-energy density and low-cost. [Extracted from the article]

Aqueous rechargeable zinc ion batteries (ARZIBs) have gained wide interest in recent years as prospective high power and high energy devices to meet the ever-rising commercial needs for large-scale eco-friendly energy storage applications. The advancement in the development of electrodes, especially cathodes for ARZIB, is faced with hurdles related to the shortage of host materials that support divalent zinc storage. Even the existing materials, mostly based on transition metal compounds, have limitations of poor electrochemical stability, low specific capacity, and hence apparently low specific energies. Herein, NH4V4O10 (NHVO), a layered oxide electrode material with a uniquely mixed morphology of plate and belt-like particles is synthesized by a microwave method utilizing a short reaction time (~0.5 h) for use as a high energy cathode for ARZIB applications. The remarkable electrochemical reversibility of Zn2+/H+ intercalation in this layered electrode contributes to impressive specific capacity (417 mAh g−1 at 0.25 A g−1) and high rate performance (170 mAh g−1 at 6.4 A g−1) with almost 100% Coulombic efficiencies. Further, a very high specific energy of 306 Wh Kg−1 at a specific power of 72 W Kg−1 was achieved by the ARZIB using the present NHVO cathode. The present study thus facilitates the opportunity for developing high energy ARZIB electrodes even under short reaction time to explore potential materials for safe and sustainable green energy storage devices. [ABSTRACT FROM AUTHOR]

The use of chalcogenide elements, such as sulfur (S) and selenium (Se), as cathode materials in rechargeable lithium (Li) and sodium (Na) batteries has been extensively investigated. Similar to Li and Na systems, rechargeable potassium–sulfur (K–S) and potassium–selenium (K–Se) batteries have recently attracted substantial interest because of the abundance of K and low associated costs. However, K–S and K–Se battery technologies are in their infancy because K possesses overactive chemical properties compared to Li and Na and the electrochemical mechanisms of such batteries are not fully understood. This paper summarizes current research trends and challenges with regard to K–S and K–Se batteries and reviews the associated fundamental science, key technological developments, and scientific challenges to evaluate the potential use of these batteries and finally determine effective pathways for their practical development. [ABSTRACT FROM AUTHOR]

All‐solid‐state sulfur batteries (ASBs) suffer from electrical and ionic conduction problems due to the insulating sulfur. By comparing three host materials with different structural characteristics, herein, carbon nanotubes (CNTs) decorated with a conductive metal sulfide (CoMoS2@CNT) is demonstrated, designed to host sulfur and exchange both Li‐ions and electrons, effectively. In this hierarchical wire structure, porous CoMoS2 nanosheets form close interfaces with sulfur, and the CNT core directly transfers electrons to the sulfur‐impregnated CoMoS2. Simultaneously, the solid electrolyte positioned on the outer region of the nanowire material ensures facile Li‐ion conduction to the sulfur‐impregnated CoMoS2. An ASB featuring a CoMoS2@CNT host material with a sulfur loading of 3 mg cm−2 exhibits a high‐areal‐capacity of 4.5 mAh cm−2 at a current density of 2.5 mA cm−2, while retaining 79.4% of its initial capacity after 300 cycles. When sulfur is replaced with SeS2 to further reinforce the charge conduction properties, all‐solid‐state SeS2 batteries (ASeS2Bs) with an extremely high‐areal‐capacity of 16.3 mAh cm−2 retain 99.3% of their initial capacities after 60 cycles at 60 °C. This study provides guidelines for the design principles of cathode composites for the ASBs and ASeS2Bs through multiangle comparative analysis. [ABSTRACT FROM AUTHOR]

Combining Li‐metal anodes (LMAs) with high‐voltage Ni‐rich layered‐oxide cathodes is a promising approach to realizing high‐energy‐density Li secondary batteries. However, these systems experience severe capacity decay due to structural degradation of high‐voltage cathodes and side reactions of electrolyte solutions with both electrodes. Herein, the use of multi‐functional additives in fluoroethylene carbonate‐based electrolyte solutions that enable the operation of successfully rechargeable high‐voltage (4.5 V) Li‐metal batteries (LMBs) with high areal capacity (>4 mAh cm−2) are reported. Customized electrolyte solutions are pivotal in passivating the electrodes, minimizing microcrack formation, and ensuring that current is uniformly distributed within cathode particles. The developed electrolyte solution protects the LMA by forming a very stable and effective solid–electrolyte interphase. Together with the Li[Ni0.78Co0.1Mn0.12]O2 cathode material, which is composed of radially aligned rod‐shaped primary particles, the developed high‐voltage LMB containing 20 mg cm−2 of cathode material delivers a high specific capacity of 230 mAh g−1 at 0.1 C and retains >86% of its initial capacity after 200 cycles at 0.5 C. This study highlights the significance of controlling the interfacial structure via electrolyte solution modification and the use of cathode materials with engineered morphologies that enhance mechanical stability. [ABSTRACT FROM AUTHOR]

Developing suitable cathodes with high capacity and high power is challenging for K‐ion batteries. Herein, electrochemical K‐ion storage properties of the layered‐type K0.4V2O5 (KVO) cathode by incorporating divalent strontium ions (Sr2+) into its crystal structure are enhanced. Divalent strontium ions (1.18 Å) are preferentially incorporated into the octahedrally coordinated K (1.38 Å) layers due to the similar ionic size compared to V4+ (0.58 Å). The introduction of 3 mmol of Sr ions in the KVO crystal improves electrical conductivity and reduces K‐ion diffusion energy barriers. In addition, the strong Sr2+ and O2− interaction acts as a structural pillar, suppressing irreversible phase transition during charge–discharge process. Multi‐physics simulations clearly confirm that the K0.34Sr0.03V2O5 (KS3VO) cathode exhibits a more uniform K‐ion distribution and enhanced reactions of K‐ions compared to the KVO cathode at various depths of discharge. As a result, the KS3VO cathode demonstrates improved reversible capacity, cycling stability, and power capability over the KVO cathode in a K‐ion cell. Synchrotron X‐ray analysis reveals how Sr substitution enhances the electrochemical K‐ion storage properties of the KS3VO cathode. In addition, the KS3VO cathode exhibits superior thermal stability and cycling stability in a full cell coupled with a hard carbon anode compared to the KVO cathode. [ABSTRACT FROM AUTHOR]

Abundant and economical sodium (Na) metal batteries promise superior energy densities compared to lithium‐ion batteries; however, they face commercialization challenges owing to problematic interfacial reactions leading to dendrite formation during cycling. This paper reports the ultra‐long and rapid operation of Na metal batteries enabled by the introduction of a vinylpyrrolidone (VP)‐based multifunctional interface stabilizer in the electrolyte. The VP electrolyte additive provides benefits such as surface flattening, durable solid electrolyte interphase layer formation, preservation of fresh Na, and acceleration of horizontal crystal growth along the (110) plane. Symmetric Na–Na cells with the stabilizer exhibit notably stable operation for over 5 000 cycles at a high current density of 5 mA cm−2, surpassing previous research. Performance improvement is also demonstrated in a full‐cell configuration with an Na3V2(PO4)2O2F cathode. This approach offers a promising solution for achieving performance levels comparable to lithium‐ion batteries in Na metal battery technology. [ABSTRACT FROM AUTHOR]

Rechargeable batteries with a Li metal anode and Ni‐rich Li[NixCoyMn1−x−y]O2 cathode (Li/Ni‐rich NCM battery) have been emerging as promising energy storage devices because of their high‐energy density. However, Li/Ni‐rich NCM batteries have been plagued by the issue of the thermodynamic instability of the Li metal anode and aggressive surface chemistry of the Ni‐rich cathode against electrolyte solution. In this study, a bi‐functional additive, adiponitrile (C6H8N2), is proposed which can effectively stabilize both the Li metal anode and Ni‐rich NCM cathode interfaces. In the Li/Ni‐rich NCM battery, the addition of 1 wt% adiponitrile in 0.8 m LiTFSI + 0.2 M LiDFOB + 0.05 M LiPF6 dissolved in EMC/FEC = 3:1 electrolyte helps to produce a conductive and robust Li anode/electrolyte interface, while strong coordination between Ni4+ on the delithiated Ni‐rich cathode and nitrile group in adiponitrile reduces parasitic reactions between the electrolyte and Ni‐rich cathode surface. Therefore, upon using 1 wt% adiponitrile, the Li/full concentration gradient Li[Ni0.73Co0.10Mn0.15Al0.02]O2 battery achieves an unprecedented cycle retention of 75% over 830 cycles under high‐capacity loading of 1.8 mAh cm−2 and fast charge–discharge time of 2 h. This work marks an important step in the development of high‐performance Li/Ni‐rich NCM batteries with efficient electrolyte additives. [ABSTRACT FROM AUTHOR]

The application of lithium metal as an anode material for next generation high energy‐density batteries has to overcome the major bottleneck that is the seemingly unavoidable growth of Li dendrites caused by non‐uniform electrodeposition on the electrode surface. This problem must be addressed by clarifying the detailed mechanism. In this work the mass‐transfer of Li‐ions is investigated, a key process controlling the electrochemical reaction. By a phase field modeling approach, the Li‐ion concentration and the electric fields are visualized to reveal the role of three key experimental parameters, operating temperature, Li‐salt concentration in electrolyte, and applied current density, on the microstructure of deposited Li. It is shown that a rapid depletion of Li‐ions on electrode surface, induced by, e.g., low operating temperature, diluted electrolyte and a high applied current density, is the underlying driving force for non‐uniform electrodeposition of Li. Thus, a viable route to realize a dendrite‐free Li plating process would be to mitigate the depletion of Li‐ions on the electrode surface. The methodology and results in this work may boost the practical applicability of Li anodes in Li metal batteries and other battery systems using metal anodes. [ABSTRACT FROM AUTHOR]

Alloying‐type metallic tin is perceived as a potential anode material for K‐ion batteries owing to its high theoretical capacity and reasonable working potential. However, pure Sn still face intractable issues of inferior K+ storage capability owing to the mechanical degradation of electrode against large volume changes and formation of intermediary insulating phases K4Sn9 and KSn during alloying reaction. Herein, the TiC/C–carbon nanotubes (CNTs) is prepared as an effective buffer matrix and composited with Sn particles (Sn–TiC/C–CNTs) through the high‐energy ball‐milling method. Owing to the conductive and rigid properties, the TiC/C–CNTs matrix enhances the electrical conductivity as well as mechanical integrity of Sn in the composite material and thus ultimately contributes to performance supremacy in terms of electrochemical K+ storage properties. During potassiation process, the TiC/C–CNTs matrix not only dissipates the internal stress toward random radial orientations within the Sn particle but also provides electrical pathways for the intermediate insulating phases; this tends to reduce microcracking and prevent considerable electrode degradation. [ABSTRACT FROM AUTHOR]

Potassium metal batteries (KMBs) coupled with layered transition metal oxides as cathode materials are a promising energy--storage technology owing to low cost and high capacity. However, uncontrollable dendritic growth in the K--metal anode and chemical reactivity of the layered transition metal oxide cathode against the electrolyte solution cause KMBs to suffer from low Coulombic efficiency, rapid capacity fading, and critical safety issues. In this study, an electrolyte engineering strategy is introduced by introducing adiponitrile (ADN) as a dual--functional electrolyte additive containing an electron--rich nitrile group (C=N) in its molecule structure. Thus, the addition of 1 wt.% ADN can alter the chemical properties of the electrolyte solution, thereby improving the anode--electrolyte and cathode--electrolyte interfacial stabilities in KMBs. The formation of a potassiophilic compound with C=N in the solid electrolyte interphase layer can guide the uniform electrodeposition of K and suppress the dendritic growth in the K--metal. Moreover, C=N forms a strong coordination bond with the oxidized transition metal, leading the reversible redox reactions by mitigating the undesirable disproportionation reaction and improving the thermal stability of the layered transition metal oxide cathode. Computational calculations and experimental characterizations are used to verify the role of ADN additive in enhancing the electrochemical properties of KMBs. [ABSTRACT FROM AUTHOR]

To meet the booming demand of high‐energy‐density battery systems for modern power applications, various prototypes of rechargeable batteries, especially lithium metal batteries with ultrahigh theoretical capacity, have been intensively explored, which are intimated with new chemistries, novel materials and rationally designed configurations. What happens inside the batteries is associated with the interaction of multi‐physical field, rather than the result of the evolution of a single physical field, such as concentration field, electric field, stress field, morphological evolution, etc. In this review, multi‐physical field simulation with a relatively wide length and timescale is focused as formidable tool to deepen the insight of electrodeposition mechanism of Li metal and the electro‐chemo‐mechanical failure of solid‐state electrolytes based on Butler‐Volmer electrochemical kinetics and solid mechanics, which can promote the future development of state‐of‐the‐art Li metal batteries with satisfied energy density as well as lifespan. [ABSTRACT FROM AUTHOR]

Exploring new anode materials with promising electrochemical capacity is essential for rechargeable sodium-ion batteries. The selection and structural design of electrode materials play key role in the development of a viable battery with high specific capacity and cycle retention. Herein, self-assembled NiCo 2 O 4 microspheres comprised of numerous sub-micron sized rods are prepared for the first time by a simple co-precipitation method. The synthesized microspheres have homogeneous morphology and a multimodal porosity. The resulting sodium ion storage properties demonstrate that the NiCo 2 O 4 microsphere anode offers excellent electrochemical performance, with a high reversible capacity of 620 mAh g −1 at a current density of 0.05 A g −1 . It also shows an exceptionally high rate capability up to 10 A g −1 equivalent to 11 C-rate, which can be attributed to the existence of capacitive behavior. Notably, the rate performance and cycling stability are significantly higher than most previously reported results of NiCo 2 O 4 nanostructures for sodium-ion batteries (SIBs). [ABSTRACT FROM AUTHOR]

Batteries using potassium metal (K‐metal) anode are considered a new type of low‐cost and high‐energy storage device. However, the thermodynamic instability of the K‐metal anode in organic electrolyte solutions causes uncontrolled dendritic growth and parasitic reactions, leading to rapid capacity loss and low Coulombic efficiency of K‐metal batteries. Herein, an advanced electrolyte comprising 1 M potassium bis(fluorosulfonyl)imide (KFSI) + 0.05 M potassium hexafluorophosphate (KPF6) dissolved in dimethoxyethane (DME) is introduced as a simple and effective strategy of regulated solvation chemistry, showing an enhanced interfacial stability of the K‐metal anode. Incorporating 0.05 M KPF6 into the 1 M KFSI in DME electrolyte solution decreases the number of solvent molecules surrounding the K ion and simultaneously leads to facile K+ de‐solvation. During the electrodeposition process, these unique features can lower the exchange current density between the electrolyte and K‐metal anode, thereby improving the uniformity of K electrodeposition, as well as potentially suppressing dendritic growth. Even under a high current density of 4 mA cm−2, the K‐metal anode in 0.05 M KPF6‐containing electrolyte ensures high areal capacity and an unprecedented lifespan with stable Coulombic efficiency in both symmetrical half‐cells and full‐cells employing a sulfurized polyacrylonitrile cathode. [ABSTRACT FROM AUTHOR]

Power sources supported by lithium-ion battery (LIB) technology has been considered to be the most suitable for public and military use. Battery quality is always a critical issue since electric engines and portable devices use power-consuming algorithms for security. For the practical use of LIBs in public applications, low heat generation, and fast charging are essential requirements, but those features are still unsatisfactory so far. In particular, the slow Li+ intercalation kinetics, lithium plating, and self-heat generation of conventional graphite-anode LIBs under fast-charging conditions are impediments to the use of these batteries by the public demands. The use of silicon-based anodes, which are associated with fast reaction kinetics and rapid Li+ diffusion, has great potential to render LIBs suitable for public use in the near future. In this perspective, the challenges in and future directions for developing silicon-based anode materials for realizing LIBs with fast-charging capability are highlighted. [ABSTRACT FROM AUTHOR]

Carbon‐free and safe power solutions, such as fast charging batteries for mid‐to‐large applications, are viable alternatives to address ever‐increasing energy demand while reducing environmental pollution. However, the self‐generated heat produced during the charge/discharge process severely hampers the performance, stability, and safety of fast charging batteries. Thus, a suitable working temperature range must be maintained to maximize efficiency. Well‐designed battery thermal management systems (BTMSs) can provide an appropriate temperature environment for maximizing battery performance with superior stability and safety. The objective of this study is to present a clear and detailed discussion on this ability of BTMSs, battery materials, and the effects of temperature on battery performance during rapid charging. Furthermore, battery modeling methods are highlighted, and the existing BTMSs are comprehensively reviewed and categorized according to their components and preparation processes. Additionally, the methods of cooling such systems based on phase change materials (PCMs), heat pipes, and thermoelectric elements, are explored. In addition, BTMSs based on air, liquids, and PCMs that undergo solid–liquid, liquid–gas, and solid–gas transitions are also discussed. [ABSTRACT FROM AUTHOR]

The Mn-based P3-type layered oxide (K 0.5 MnO 2) is a promising cathode material for K-ion batteries (KIBs) because of its low cost, high specific capacity, and simple synthesis. However, it suffers from severe capacity loss and sluggish K+ diffusion kinetics, which are mainly attributed to multiple phase transitions and the Jahn–Teller distortion of Mn3+. To address these challenges, herein, the Mg and Cu co-substitution strategy is proposed to synthesize the P3-type K 0.5 Mn 0.8 Mg 0.1 Cu 0.1 O 2 (P3-KMMCO) as a cathode for KIBs. The presence of divalent Mg2+ and Cu2+ in the crystal structure of P3-KMMCO play the critical functions in regulating the Jahn–Teller-active Mn3+, thereby suppressing the complex phase transitions and improving the K+ diffusion kinetics during charging and discharging. As a result, the P3-KMMCO cathode demonstrates the high reversible capacity, outstanding cycling stability and power capability. A combination study of synchrotron-based X-ray analysis and first-principles calculations is used to validate the enhanced electrochemical K+ storage properties of the P3-KMMCO cathode. We introduce the Mg and Cu co-substituted P3-K 0.5 MnO 2 (P3-KMO) cathode. This co-substitution strategy regulated the Mn oxidation state and induced the disordering within TMO 2 slab, which relaxed the Jahn-Teller distortion of Mn3+ and suppressed the K+/vacancy ordering. As a result, P3-K 0.5 Mn 0.8 Mg 0.1 Cu 0.1 O 2 (P3-KMMCO) cathode demonstrated continuous phase transition with sloping voltage profiles, leading to superior cycling stability and power capability. [Display omitted] • The synergy effect of Mg and Cu co-substitution suppress the Jahn-Teller distortion. • The P3-KMMCO cathode exhibits a superior cycling stability and power capability. • DFT calculations confirm suppression of Jahn-Teller distortion in P3-KMMCO cathode. [ABSTRACT FROM AUTHOR]

Recently, a novel electrochemical regulation associated with a deposition/dissolution reaction on an electrode surface has been proven to show superiority in large-scale energy storage systems (ESSs). Hence, in the search for high-performance electrodes showcasing these novel regulations, we utilized a low-cost ZnO microsphere electrode to construct aqueous rechargeable batteries (ARBs) that supplied a harvestable and storable charge through electrochemical deposition/dissolution via a reversible manganese oxidation reaction (MOR)/manganese reduction reaction (MRR), respectively, induced by the inherent formation/dissolution of zinc basic sulfate in a mild aqueous electrolyte solution containing 2 M ZnSO4 and 0.2 M MnSO4. [ABSTRACT FROM AUTHOR]

Potassium–sulfur (K–S) batteries are emerging as low‐cost and high‐capacity energy‐storage technology. However, conventional K–S batteries suffer from two critical issues that have not yet been successfully resolved: the dissolution of potassium polysulfides (KPS) into the liquid electrolyte and the formation of K dendrites on the K metal anode, which lead to inadequate cycling efficiencies with a low reversible capacity. Herein, a high‐capacity and long cycle‐life K–S battery consisting of a highly concentrated electrolyte (HCE) (4.34 mol kg−1 potassium bis(fluorosulfonyl)imide in a 1,2‐Dimethoxyethane) and a sulfurized polyacrylonitrile (SPAN) cathode is presented The application of a HCE efficiently suppresses the dendritic growth of K, as evidenced by operando optical imaging and phase field modeling, owing to the reduced K‐ion depletion on the electrode surface and a uniform Faradaic current density over the K metal anode surface. Additionally, because S is covalently bonded to the C backbone of PAN in the SPAN structure, the SPAN cathode inhibits the dissolution of KPS. These features generate synergy that the proposed K–S battery can provide a practical areal capacity of 2.5 mAh cm−2 and unprecedented lifetimes with high Coulombic efficiencies over 700 cycles. [ABSTRACT FROM AUTHOR]