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Transition metal oxides are considered promising anode materials for high performance flexible electrodes due to their abundant reserves and excellent specific capacity. However, their inherent low conductivity, large volume effect, and poor cycling performance limit their applications. Herein, we report a novel "spontaneous complexation and exfoliation" strategy for the fabrication of flexible MnO NCs@rGO thin-film electrodes, which overcomes the aforementioned drawbacks and pushes the mechanical flexibility and lithium-ion (Li+) storage performance to a higher level. The combination of large-area few-layer reduced graphene oxide (rGO) films and ultrafine MnO nanocrystals (MnO NCs) provides a high density of electrochemical active sites. Notably, the layer-by-layer embedded structure not only enables the MnO NCs@rGO electrodes to withstand various mechanical deformations but also produces a strong synergistic effect of enhanced reaction kinetics by providing an enlarged electrode/electrolyte contact area and reduced electron/ion transport resistance. The elaborately designed flexible MnO NCs@rGO anode provides a specific capacity of about 1220 mAh g−1 over 1000 cycles, remarkable high-rate capacity (50.0 A g−1), and exceptional cycling stability. Finally, the assembled flexible lithium-ion full cells achieve zero capacity loss during repeated large-angle bending, demonstrating immense potential as a high-performance flexible energy storage device. This work provides valuable insights into unique structural designs for durable and ultra-fast lithium ion batteries. [ABSTRACT FROM AUTHOR]

Li4Ti5O12 (LTO) batteries are known for safety and long lifespan due to zero-strain and stable lattice. However, their low specific capacity and lithium-ion diffusion limit practical use. This study explored modifying LTO through yttrium doping by hydrothermal method to form Li4Y0.2Ti4.8O12 nanoparticles. This approach optimized electron and ion transport, markedly enhancing rate and cycle performance. XRD and TEM revealed that Y addition increased interplanar distance of LTO and widened Li+ transport pathways. XPS indicated that Y doping augmented the oxygen vacancy concentration and Ti3+ content. UV tests demonstrated a band gap reduction from 3.72 eV to 2.94 eV, accompanied by enhanced electronic conductivity. EIS tests showed lithium-ion diffusion coefficient remarkably increased to 1.27 × 10–10 cm2 s−1. The initial discharge capacity of Li4Y0.2Ti4.8O12 at 1 A g−1 reached 198.9 mAh g−1 and retained 89.3% capacity after 1000 cycles. At 6 A g−1, the discharge capacity was 161.1 mAh g−1, while at an ultra-high current density of 20 A g−1, it reached 78.8 mAh g−1, highlighting its robust rate performance. The yttrium-doped and nano-morphology stabilizes the LTO lattice, enhancing rate performance and cycling stability. This study reveals that LTO has the potential to be used in the high-energy fast-charging storage market. [ABSTRACT FROM AUTHOR]

Lithium titanium oxide (LTO) is a promising anode material due to its ability to store lithium through intercalation reactions. However, its electrochemical performance is limited by poor electron conductivity and side reactions with the electrolyte. In this study, plasma‐enhanced chemical vapor deposition (PECVD) is employed to introduce oxygen vacancies and self‐doped Ti3+ into LTO to improve the internal conductivity. Subsequent carbon coating and aluminum‐doped lithium lanthanum zirconate garnet (LLZO) layers resulted in a multi‐layered composite denoted as LTO−L‐x. Morphological analyses using SEM and TEM demonstrated the successful growth of Al‐doped LLZO on carbon‐coated LTO. Aluminum ions in LLZO cubic structure are crucial for stabilizing the high ionic conductive phase during cooling, as confirmed by X‐ray diffraction. The dual coating layers have a significant impact on the rate capability, reducing polarization gaps and enabling higher capacities at various current rates. Long‐term cycling tests reveal the robustness of the composite, with LTO−L‐1.0 retaining 90.8 % capacity after 4000 cycles at 1.0 A g−1. This underscores the sustained high electronic and ionic conductivity facilitated by the dual coating layers. The study contributes to the design of advanced anode materials for lithium‐ion batteries, emphasizing the importance of tailored coating strategies to address conductivity and stability challenges. [ABSTRACT FROM AUTHOR]

Abstract Li4Ti5O12 (LTO) batteries are known for safety and long lifespan due to zero-strain and stable lattice. However, their low specific capacity and lithium-ion diffusion limit practical use. This study explored modifying LTO through yttrium doping by hydrothermal method to form Li4Y0.2Ti4.8O12 nanoparticles. This approach optimized electron and ion transport, markedly enhancing rate and cycle performance. XRD and TEM revealed that Y addition increased interplanar distance of LTO and widened Li+ transport pathways. XPS indicated that Y doping augmented the oxygen vacancy concentration and Ti3+ content. UV tests demonstrated a band gap reduction from 3.72 eV to 2.94 eV, accompanied by enhanced electronic conductivity. EIS tests showed lithium-ion diffusion coefficient remarkably increased to 1.27 × 10–10 cm2 s−1 . The initial discharge capacity of Li4Y0.2Ti4.8O12 at 1 A g−1 reached 198.9 mAh g−1 and retained 89.3% capacity after 1000 cycles. At 6 A g−1, the discharge capacity was 161.1 mAh g−1, while at an ultra-high current density of 20 A g−1, it reached 78.8 mAh g−1, highlighting its robust rate performance. The yttrium-doped and nano-morphology stabilizes the LTO lattice, enhancing rate performance and cycling stability. This study reveals that LTO has the potential to be used in the high-energy fast-charging storage market. Graphical Abstract

Potassium‐ion batteries (PIBs) capable of achieving full charge in minutes, or even in seconds, while maintaining high energy densities, are highly desirable for practical applications. However, significant challenges exist in developing electrodes that can sustain both high capacity and rapid charging rates. Conventional phosphorus‐carbon composites, limited by the intrinsic common carbon materials structure, often fail to prevent the edges reconstruction of black phosphorus (BP), thereby limiting its potential advantages as a high‐capacity, high‐rate anode. This study addresses these challenges by grafting BP onto a super‐porous carbon (SPC) framework to serve as an anode for potassium storage. The large number of open pores in SPC ensures the uniform distribution of BP nanoparticles in this carbon matrix, realizing the complete potassiation reactions and uniform volumetric strain dispersion. The abundant defects significantly promote the phosphorus‐carbon reconstruction between edge carbon atoms and edge phosphorus atoms, effectively inhibiting the P‐P edge reconstruction of BP to ensure open edges for rapid K+ diffusion. As a result, the composite exhibits excellent performance in potassium storage, demonstrating superior capacity, charging rates, and cycling durability. This research provides a new insight into enhancing BP‐base anodes, offering favorable guidance for the development of high‐performance materials. [ABSTRACT FROM AUTHOR]

The paradigm shift toward the closed‐loop recycling of spent lithium‐ion batteries necessitates the direct, efficient cathode recovery that goes beyond the traditional pyrometallurgy and hydrometallurgy techniques, meanwhile avoiding substantial energy consumption, tedious procedures, or chemical contamination. In this study, a straightforward, dual‐functional upcycling approach is presented for the spent nickel‐rich cathodes to boost their high‐rate performance. Specifically, the protocol rationally employs the Li vacancy within the degraded oxide to minimize the La diffusion barrier, expanding the lattice spacing of the layered structure; the Li+ conductive, conformal LiLaO2 encapsulation further suppresses the interfacial acid corrosion and structural deterioration into the rock‐salt phase. Transmission‐mode X‐ray diffraction tracks the reversible lattice breathing of the regenerated cathode in operando, suggesting the continuous, kinetically boosted solid‐solution process with all the microcracks repaired. The as‐assembled regenerated LiNi0.8Co0.1Mn0.1O2/Graphite pouch cell (1.4Ah) thus achieves 91.0% capacity retention for 500 cycles, the energy density of 277 Wh kg−1 as well as extreme power output of 1030 W kg−1 at the cell level. This upcycling strategy paves the way for value‐added utilization of the retired Ni‐rich cathodes in practical high‐rate battery prototypes. [ABSTRACT FROM AUTHOR]

P2‐type layered transition metal oxides are potential cathodes for sodium‐ion batteries (SIBs), but they commonly suffer from severe capacity degradation owing to multiple phase transitions and Na+/vacancy ordering during the extraction/insertion process. An anionic/cationic co‐doping strategy at high sodium contents is proposed to effectively achieve high‐rate and long‐term stability of P2‐Na0.67Ni0.33Mn0.67O2. The resulting Na0.75Mg0.1Ni0.23Mn0.67O1.95F0.05 (NMNMOF) cathode delivers a reversible capacity of 116 mAh g−1 at 75 mA g−1 and maintains an initial capacity of 73% at 1500 mA g−1 after 1000 cycles. The Mg/F anionic/cationic co‐doping strategy impacts the local environment of the surrounding transition metal and oxygen, regulates the electron distribution, and modifies the initial diffusion state of Na sites, enhancing the diffusion ability of Na+. Moreover, the phase transition of P2‐O2 is well suppressed and the decrease in Mn3+ content greatly alleviates the Jahn–Teller effect to enhance structural stability. The full‐cell devices with NMNMOF cathode and hard carbon anode demonstrate a high capacity of 80 mAh g−1 at 10 C and an excellent cycle life of over 500 cycles for applications. The anionic/cationic co‐doping strategy will inspire the rational design of P2‐type layered oxides and provide a new perspective for advanced SIBs. [ABSTRACT FROM AUTHOR]

Lithium‐carbon dioxide batteries (LCBs) require a thick cathode electrode to fulfill their theoretical energy density and high areal capacity (mAh cm−2). However, understanding the design of thick porous electrodes in LCBs is challenging because of the complexity of coupled multispecies transport. Herein, a link is established between the microscopic behaviors of thick electrodes and macroscopic electrochemical performance through a spatio‐temporal resolution technique, filling the gap in knowledge on the degradation mechanism of thick electrodes. Surprisingly, the worst utilization site with the least product deposition is in the central part of the electrode rather than the traditionally presumed separator face. The secondary structure and reaction pathway of solid products exhibit a clear tendency toward spatial growth (on the electrode surface or in the interior). Combined with quantitative modeling, a critical current density shifting the dominance is found from CO2 to Li+ ions, thereby reversing the gradient of the product distribution. Finally, a hotspot map of failure mechanisms with different operating protocols is provided, serving as a guideline for the future design of thick electrodes. This work breaks the knowledge of multi‐field coupling within porous thick electrodes and can be extended to advanced Na (Li)‐CO2 (O2) battery design. [ABSTRACT FROM AUTHOR]

Beyond the high theoretical capacity, conversion‐alloying metal chalcogenides (CAMCs) exhibit exceptional high‐rate performance as Li‐ion battery electrodes. However, the inherent origin of the high‐rate performance remains elusive, especially given the lower intrinsic conductivity of CAMCs. Here, the correlation between phase evolution and charge transport dynamics in fully activated CAMCs is systematically investigated, elucidating a current‐adaptive Li‐ion storage mechanism to explain the anomalous high‐rate performance. Briefly, the deconversion reaction manipulated by ion diffusion acts as a "regulator" to adaptively modulate the transition from metal (high electronic conductivity) and lithium chalcogenides (high ionic conductivity) to CAMCs, thus removing the charge transport bottleneck without affecting the formation of the metal feedstock required for the alloying reaction. On this basis, the high capacity can be maintained at high rates through a "fading‐free" alloying reaction. This study offers a novel perspective for the design of high‐rate electrode materials. [ABSTRACT FROM AUTHOR]

Lithium (Li) metal is considered as a promising anode material for high‐energy batteries; yet, its practical application is hindered by uncontrolled Li dendrite growth, especially at a high rate. Herein, a dual conductive gradient V2CTx/MoO3 (DG‐V2CTx/MoO3) host that integrates electronic/ionic conductive gradients and lithiophilicity is prepared by layer‐by‐layer assembly for dendrite‐free Li anodes. Gradient LiF deriving from different amount of V2CTx endows a good ionic conductive gradient; while, MoO3 is regarded as a spacer to avoid the restacking of V2CTx, increasing space for Li deposition. The dual conductive gradients effectively optimize the current density and Li+ flux distribution at the bottom, achieving fast reduction of Li+ and a "bottom–up" Li deposition mode. Meanwhile, the lithiophilic V2CTx and MoO3 guide the homogeneous Li growth. As a result, the symmetrical half‐cells based on DG‐V2CTx/MoO3@Li anodes conduct 700 h at 5 mAh cm−2 and 20 mA cm−2. The DG‐V2CTx/MoO3@Li||LiFePO4 full‐cells maintain a capacity retention of 85.4% after 1350 cycles at 2 C. Remarkably, the DG‐V2CTx/MoO3@Li||LiNi0.6Co0.2Mn0.2O2 full‐cells can run 150 cycles with 80.6% capacity retention even at harsh conditions. The well‐adjusted materials and structures with both dual conductive gradients and lithiophilic properties will bring inspiration for novel material design of other metal batteries. [ABSTRACT FROM AUTHOR]

Silicon monoxide (SiO) is widely recognized as a promising anode material for next-generation lithium-ion batteries. Owing to its metastable amorphous structure, SiO exhibits a highly complex degree of crystallization at the microscopic level, which significantly influences its electrochemical behavior. As a consequence, accurately regulating the crystallization of SiO, and further establishing the relationship between crystallinity and electrochemical performance are very critical for SiO anodes. In this article, carbon-coated SiO materials with different crystallinity degrees were synthesized using lithium hydroxide monohydrate (LiOH·H2O) as a structural modifier to reveal this rule. Additionally, moderate amount of LiOH·H2O addition results in the forming of an oxygen-rich shell, which effectively inhibits the inward migration of oxygen atoms on the SiO surface and suppresses volume expansion. However, the crystallinity of SiO will gradually enhance and the crystalline phase appears with increasing the amount of LiOH·H2O, which will generate a deteriorative Li+ diffusion kinetic. After balancing the above two contradictions, a mass fraction of 1% LiOH·H2O for the additive yielded SiO@C-1, characterized by optimal crystallinity. SiO@C-1 demonstrates exceptional long-cycle stability with 74.8% capacity retention after 500 cycles at 1 A·g−1. Furthermore, it achieves a capacity retention of 52.2% even at a high density of 5 A·g−1. This study first reveals the relationship between SiO crystallinity and electrochemical performance, which efficiently guides the design of high-performance SiO anodes. [ABSTRACT FROM AUTHOR]

Sodium-ion batteries (SIBs) are an attractive battery system because of similar characteristics to lithium-ion batteries (LIBs) and large Na element abundance. Nevertheless, exploring stable, high-capacity and high-rate anode materials for SIBs is still challenging now. Herein, diethylenetriamine (DETA) molecular template derived ultrathin N-doped carbon (NC) layer decorated CoSe2 nanobelts (CoSe2/NC) are prepared by solvothermal reaction followed by calcination process. The CoSe2/NC exhibits large potential as an anode for SIBs. Experiments and theoretical calculations reveal that the in situ formed conductive ultrathin NC layer can not only relieve the volume change of CoSe2 but also accelerate electron and ion transport. In addition, the nanobelt structure of CoSe2/NC with abundant exposed active sites can obviously accelerate the electrochemical kinetics. Under the synergistic effect of special nanobelt structure and NC layer, the rate as well as cycling performances of CoSe2/NC are obviously improved. A superior capacity retention of 94.8% is achieved at 2 A·g−1 after 2000 cycles. When using Na3V2(PO4)3 cathodes, the pouch full batteries can work steadily at 0.5 C, verifying the application ability. CoSe2/NC anodes also exhibit impressive performances in LIBs and potassium-ion batteries (PIBs). [ABSTRACT FROM AUTHOR]

Sodium-ion batteries (SIBs) have garnered significant interest in energy storage due to their similar working mechanism to lithium ion batteries and abundant reserves of sodium resource. Exploring facile synthesis of a carbon-based anode materials with capable electrochemical performance is key to promoting the practical application of SIBs. In this work, a combination of petroleum pitch and recyclable sodium chloride is selected as the carbon source and template to obtain hard carbon (HC) anode for SIBs. Carbonization times and temperatures are optimized by assessing the sodium ion storage behavior of different HC materials. The optimized HC exhibits a remarkable capacity of over 430 mA·hg−1 after undergoing full activation through 500 cycles at a density of current of 0.1 A·g−1. Furthermore, it demonstrates an initial discharge capacity of 276 mAh·g−1 at a density of current of 0.5 A·g−1. Meanwhile, the optimized HC shows a good capacity retention (170 mAh·g−1 after 750 cycles) and a remarkable rate ability (166 mAh·g−1 at 2 A·g−1). The enhanced capacity is attributed to the suitable degree of graphitization and surface area, which improve the sodium ion transport and storage. [ABSTRACT FROM AUTHOR]

Creating defects by heteroatom doping is commonly approved in respect of enhancing fast sodium‐ion storage of carbonaceous anodes ascribing to rich external defects, but the contribution of intrinsic carbon defects (e.g., vacancy) in improving rate‐capability has rarely been investigated. Here, a bio‐derived fibrous hard carbon with high‐reversible intrinsic defects is synthesized via metal‐assisted‐catalytic strategy. It is found that sp2‐hybridized carbon is united through catalytic‐tuning during thermal‐etching process along with the formation of low‐potential planar intrinsic carbon defects (vacancies and non‐hexagonal carbon rings) by sacrificing poor‐reversible carbon edges. Such integrated structures greatly improve the reversibility of defective sites and charge transfer kinetics, thus enhancing the slope sodium‐storage capacity of carbon below 1 V even at high current densities. Thus‐obtained fibrous carbon anodes enable boosted initial coulombic efficiency (≈90%) and ultrahigh‐rate capability in both half‐ (222.2 mAh g−1at 50 A g−1) and full‐cell (200 C, charged/discharged in ≈10 s). Interestingly, compared with meso‐/macroporous structures, such micropore‐dominated carbon fibers are more beneficial for fabricating high‐mass‐loading, crack‐free thick electrodes (>10 mg cm−2) with considerable areal‐capacity over 3.0 mAh cm−2. Paired with high‐loading Na3V2PO4 cathode (14.4 mg cm−2), full‐cell achieves admirable areal‐capacity over 1.4 mAh cm−2 and peak areal‐energy/power‐density of 3.2/74 mW cm−2. [ABSTRACT FROM AUTHOR]

Redox-active organic materials are capturing growing attention as cathode materials for sustainable alkaline metal ion batteries. However, the storage of Na+ in most organic materials-based cathodes is plagued by low capacity and unsatisfying rate performance due to their low active site densities and limited exposed active sites. Herein, two polyimide-linked covalent organic frameworks (COFs), namely HATN-PD-COF and HATN-TAB-COF, were fabricated from hydrothermal synthesis with redox-active triphenylene-2,3,6,7,10,11-hexacarboxylic acid and aromatic amines as starting materials. Powder X-ray diffraction and electron microscopy analysis indicate the high crystalline nature of these COFs with AA stacking configuration and orderly mesoporous tunnel. N2 sorption measurement discloses the permanent porosity of these two COFs with a Brunauer-Emmett-Teller surface area of 1,065–1,200 m2 g−1 and a large pore size of 2.0–3.1 nm. Galvanostatic intermittent titration technique and density functional theory calculations reveal the facile Na+ ion diffusion along the mesoporous tunnel of these COFs with a small energy barrier of 0.13–0.40 eV. In particular, the as-prepared COFs based-cathodes show ultrafast and stable Na+ storage associated with their conjugated electronic structure, highly ordered mesoporous tunnel, robust structure, and redox-active C=N/C=O-rich framework as exemplified by the high reversible capacity of 210 mA h g−1 at 200 mA g−1, record-high rate performance (195 mA h g−1 at a high current density of 10,000 mA g−1) among organic electrodes and the capacity retention of nearly 91% at 10,000 mA g−1 after 7,000 cycles for HATN-PD-COF. [ABSTRACT FROM AUTHOR]

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Abstract Polyethylene oxide (PEO)‐based polymer solid electrolytes (PSE) have been pursued for the next‐generation extremely safe and high‐energy‐density lithium metal batteries due to their exceptional flexibility, manufacturability, and lightweight nature. However, the practical application of PEO‐PSE has been hindered by low ionic conductivity, limited lithium‐ion transfer number (tLi+), and inferior stability with lithium metal. Herein, an ultrathin composite solid‐state electrolyte (CSSE) film with a thickness of 20 μm, incorporating uniformly dispersed two‐dimensional fluorinated boron nitride (F‐BN) nanosheet fillers (F‐BN CSSE) is fabricated via a solution‐casting process. The integration of F‐BN effectively reduces the crystallinity of the PEO polymer matrix, creating additional channels that facilitate lithium‐ion transport. Moreover, the presence of F‐BN promotes an inorganic phase‐dominated electrolyte interface film dominated by LiF, Li2O, and Li3N on the lithium anode surface, greatly enhancing the stability of the electrode‐electrolyte interface. Consequently, the F‐BN CSSE exhibits a high ionic conductivity of 0.11 mS cm−1 at 30°C, high tLi+ of 0.56, and large electrochemical window of 4.78 V, and demonstrates stable lithium plating/striping behavior with a voltage of 20 mV for 640 h, effectively mitigating the formation of lithium dendrites. When coupled with LiFePO4, the as‐assembled LiFePO4|F‐BN CSSE|Li solid‐state battery achieves a high capacity of 142 mAh g−1 with an impressive retention rate of 82.4% after 500 cycles at 5 C. Furthermore, even at an ultrahigh rate of 50 C, a capacity of 37 mAh g−1 is achieved. This study provides a novel and reliable strategy for the design of advanced solid‐state electrolytes for high‐rate and long‐life lithium metal batteries.

High‐rate and stable Zn‐ion batteries working at low temperatures are highly desirable for practical applications, but are challenged by sluggish kinetics and severe corrosion. Herein, inspired by frost‐resistant plants, we report trace hydroxyl‐rich electrolyte additives that implement a dual remodeling effect for high‐performance low‐temperature Zn‐ion batteries. The additive with high Zn absorbability not only remodels Zn2+ primary solvent shell by alternating H2O molecules, but also forms a shielding layer thus remodeling the Zn surface, which effectively enhances fast Zn2+ de‐solvation reaction kinetics and prohibits Zn anode corrosion. Taking trace α‐D‐glucose (αDG) as a demonstration, the electrolyte obtains a low freezing point of −55.3 °C, and the Zn//Zn cell can stably cycle for 2000 h at 5 mA cm−2 under −25 °C, with a high cumulative capacity of 5000 mAh cm−2. A full battery that stably operates for 10000 cycles at −50 °C is also demonstrated. [ABSTRACT FROM AUTHOR]

Separators are becoming increasingly important in both academic research and industrial production as a means of enhancing the performance of lithium‐ion batteries (LIBs), particularly at a high rate. However, fast charge–discharge processes will produce local heat accumulation, which accelerates the local reaction rate of Li+ to form lithium dendrites. Commercial polyolefin separators fail to tackle the above issue due to inferior thermal stability. Herein, a core–shell structure is proposed to reinforce the polyvinylidene fluoride‐hexafluoropropylene (PVDF‐HFP) matrix through encircling carbon nanotube (CNT) by adherent polydopamine (PDA). The core–shell 3D structure with PDA avoids the short circuits caused by the electrically conductive CNT, and meantime, the CNT serves as an effective radiator for dispersing local heat sources verified through finite element analysis. The composite separator allows LIBs to achieve high Li+ conductivity (0.49 × 10−3 S cm−1) and Li+ transfer number (0.74), resulting in a high capacity retention of 87.35% after 800 cycles at 5C. In particular, the safety is confirmed that the composite separator avoids violent growth of lithium dendrites caused by local heat accumulation through phase‐field simulations. This work suggests a promising approach for the fabrication of core–shell nanotube composite separators for high‐rate and safe LIBs. [ABSTRACT FROM AUTHOR]

Mixing transition metal cations in nearly equiatomic proportions in layered oxide cathode materials is a new strategy for improving the performances of Na-ion batteries. The mixing of cations not only offers entropic stabilization of the crystal structure but also benefits the diffusion of Na ions with tuned diffusion activation energy barriers. In light of this strategy, a high-rate Na0.6(Ti0.2Mn0.2Co0.2Ni0.2Ru0.2)O2 cathode was designed, synthesized, and investigated, combining graph-based deep learning calculations and complementary experimental characterizations. This new cathode material delivers high discharge capacities of 164 mA g-1 at 0.1 C and 68 mAh g-1 at a very high rate of 86 C, demonstrating an outstanding high rate capability. Ex situ and operando synchrotron X-ray diffraction were used to reveal the detailed structural evolution of the cathode upon cycling. Using the climbing-image nudged elastic-band calculation and Ab initio molecular dynamics simulations, we show that the optimal transition metal composition enables a percolating network of low barrier pathways for fast, macroscopic Na diffusion, resulting in the observed high rate performance.

We present the synthesis of optically active polymers derived from S‐phenylethyl acrylate and R‐phenylethyl acrylate for the first time. Cu(0) wire‐catalyzed single electron transfer‐living radical polymerization (SET‐LRP) methodology which provides a feasible platform makes its new application in designing and developing these two polymers. At various degrees of polymerizations (DPs) ranging from 100 to 400, first‐order kinetics is observed. In all cases, SET‐LRP demonstrates a rapid polymerization rate while maintaining excellent control over polymer's molecular weight, polydispersity and chain‐end functionality. These advantages facilitate the development of both homopolymers and block copolymers through in situ chain extensions. The circular dichroism measurement confirms that the SET‐LRP method yields optically active polymers derived from two enantiomeric monomers, which exhibit mirrored spectra. [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li–S) batteries are widely regarded as promising next‐generation battery systems due to their impressive theoretical energy density of 2600 Wh kg−1. However, practical high‐energy‐density Li–S pouch cells suffer from rapid performance degradation under high working rates. Herein, the performance degradation mechanism of 400 Wh kg−1 Li–S pouch cells is systematically investigated under a high cycling rate of 0.2 C. Focusing on the reduced specific capacity and increased cell polarization, the sluggish cathodic sulfur redox kinetics under lean‐electrolyte and high‐rate conditions is identified as the main limitation. Further polarization decoupling indicates the cathodic activation polarization contributes dominantly to the increased cell polarization. Accordingly, a delicately designed electrolyte using dimethyl diselenide as the kinetic promoter is proposed to enable the Li–S pouch cells to work at 0.2 C with reduced cell polarization. This work clarifies the sluggish cathodic interfacial charge transfer kinetics as the main challenge for high‐energy‐density Li–S batteries at high rates and is expected to inspire rational strategy design for achieving advanced Li–S batteries. [ABSTRACT FROM AUTHOR]

With the popularity of new energy vehicles, the demand for fast charging and rapid discharge is further increasing. Layered high-nickel ternary materials possess significant potential as cathode materials for electric vehicle batteries due to their high capacity, low cost, and environmental friendliness. In this paper, lithium metaborate, lithium hydroxide, and 90 series high-nickel ternary material precursors were used as raw materials to synthesize a series of B-doped cathode materials with highly textured structures. It is found that B doping can improve the lithium-ion diffusion rate, and the B-modified cathode material also has excellent rate performance, and the 0.5% B-doped cathode material still maintains a discharge specific capacity of 157.13 mAh/g at a discharge rate of 10 C. Additionally, the test of microparticle compressor shows that boron doping can significantly improve the mechanical properties of ternary cathode materials and inhibit the formation of microcracks. In summary, this study puts forward a new idea for the modification of high-nickel ternary cathode materials and promotes the commercialization of high-nickel ternary cathode materials. [ABSTRACT FROM AUTHOR]

The artificial solid electrolyte interphase (SEI) plays a pivotal role in Zn anode stabilization but its long‐term effectiveness at high rates is still challenged. Herein, to achieve superior long‐life and high‐rate Zn anode, an exquisite electrolyte additive, lithium bis(oxalate)borate (LiBOB), is proposed to in situ derive a highly Zn2+‐conductive SEI and to dynamically patrol its cycling‐initiated defects. Profiting from the as‐constructed real‐time, automatic SEI repairing mechanism, the Zn anode can be cycled with distinct reversibility over 1800 h at an ultrahigh current density of 50 mA cm−2, presenting a record‐high cumulative capacity up to 45 Ah cm−2. The superiority of the formulated electrolyte is further demonstrated in the Zn||MnO2 and Zn||NaV3O8 full batteries, even when tested under harsh conditions (limited Zn supply (N/P≈3), 2500 cycles). This work brings inspiration for developing fast‐charging Zn batteries toward grid‐scale storage of renewable energy sources. [ABSTRACT FROM AUTHOR]

Simultaneously high-rate and high-safety lithium-ion batteries (LIBs) have long been the research focus in both academia and industry. In this study, a multifunctional composite membrane fabricated by incorporating poly(vinylidene fluoride) (PVDF) with magnesium carbonate hydroxide (MCH) nanofibers was reported for the first time. Compared to commercial polypropylene (PP) membranes and neat PVDF membranes, the composite membrane exhibits various excellent properties, including higher porosity (85.9%) and electrolyte wettability (539.8%), better ionic conductivity (1.4 mS·cm−1), and lower interfacial resistance (93.3 Ω). It can remain dimensionally stable up to 180 °C, preventing LIBs from fast internal short-circuiting at the beginning of a thermal runaway situation. When a coin cell assembled with this composite membrane was tested at a high temperature (100 °C), it showed superior charge–discharge performance across 100 cycles. Furthermore, this composite membrane demonstrated greatly improved flame retardancy compared with PP and PVDF membranes. We anticipate that this multifunctional membrane will be a promising separator candidate for next-generation LIBs and other energy storage devices, in order to meet rate and safety requirements. [ABSTRACT FROM AUTHOR]

High‐performance metal fluoride cathodes are crucial to design ultrahigh‐capacity lithium metal batteries for taking part in the next‐generation energy storage market. However, their insulating nature and sluggish reaction kinetics result in voltage hysteresis, low‐rate capability, and rapid capacity degradation. Herein, a generalizable one‐step melt synthesis approach is reported to construct hetero‐packing nanostructures of FeF3@C‐Asphalt nanocomposites, where ultrafine FeF3 nanoparticles are homogeneously covered by a high conductive carbon framework. By the electrochemical kinetics calculation and multiphysics simulations, this FeF3@C‐Asphalt nanocomposites consist of ultrafine nanoparticles and a constrained carbon framework, offering a high tap density (1.8 g cm−3), significantly improved conductivity, and enhanced charge pathways, and thereby enabling the fast electron transport, rapid ion migration, depressed electrode internal stress, and mitigated volume expansion. As a result, the optimized FeF3@C‐Asphalt cathode delivers a high capacity of 517 mAh g−1, high cyclic stability of 87.5% after 1000 cycles under 5 A g−1 (10 C), and excellent capacity retention of 77% from 0.5 A g−1 to 10 A g−1 (20 C, 250 mAh g−1). The work provides an easy‐to‐operate and low‐cost approach to accomplish high cyclic stability metal fluoride‐lithium batteries, which will guide the development of fast‐charging ultrahigh‐capacity cathode materials for the new energy industry. [ABSTRACT FROM AUTHOR]

The slow reaction kinetics and structural instability of organic electrode materials limit the further performance improvement of aqueous zinc‐organic batteries. Herein, we have synthesized a Z‐folded hydroxyl polymer polytetrafluorohydroquinone (PTFHQ) with inert hydroxyl groups that could be partially oxidized to the active carbonyl groups through the in situ activation process and then undertake the storage/release of Zn2+. In the activated PTFHQ, the hydroxyl groups and S atoms enlarge the electronegativity region near the electrochemically active carbonyl groups, enhancing their electrochemical activity. Simultaneously, the residual hydroxyl groups could act as hydrophilic groups to enhance the electrolyte wettability while ensuring the stability of the polymer chain in the electrolyte. Also, the Z‐folded structure of PTFHQ plays an important role in reversible binding with Zn2+ and fast ion diffusion. All these benefits make the activated PTFHQ exhibit a high specific capacity of 215 mAh g−1 at 0.1 A g−1, over 3400 stable cycles with a capacity retention of 92 %, and an outstanding rate capability of 196 mAh g−1 at 20 A g−1. [ABSTRACT FROM AUTHOR]

Alloying‐type bismuth with high volumetric capacity has emerged as a promising anode for sodium‐ion batteries but suffers from large volume expansion and continuous pulverization. Herein, a coordination constraint strategy is proposed, that is, chemically confining atomic Bi in an intercalation host framework via reconstruction‐favorable linear coordination bonds, enabling a novel quasi‐topological intercalation mechanism. Specifically, micron‐sized Bi0.67NbS2 is synthesized, in which the Bi atom is linearly coordinated with two S atoms in the interlayer of NbS2. The robust Nb−S host framework provides fast ion/electron diffusion channels and buffers the volume expansion of Na+ insertion, endowing Bi0.67NbS2 with a lower energy barrier (0.141 vs. 0.504 eV of Bi). In situ and ex situ characterizations reveal that Bi atom alloys with Na+ via a solid‐solution process and is constrained by the reconstructed Bi−S bonds after dealloying, realizing complete recovery of crystalline Bi0.67NbS2 phase to avoid the migration and aggregation of atomic Bi. Accordingly, the Bi0.67NbS2 anode delivers a reversible capacity of 325 mAh g−1 at 1 C and an extraordinary ultrahigh‐rate stability of 226 mAh g−1 at 100 C over 25 000 cycles. The proposed quasi‐topological intercalation mechanism induced by coordinated mode modulation is expected to be be conducive to the practical electrode design for fast‐charging batteries. [ABSTRACT FROM AUTHOR]

In this article BF3 etching is applied to fabricate basic SEI (B‐SEI) layers enriched with LiF and LixBFy. Artificial solid electrolyte interface (A‐SEI) with a "stromatolite" structure is formed on top of the B‐SEI growth during the charge‐discharge cycles. The structure of A‐SEI is characterized laterally and longitudinally by distribution of TEM elements and depth‐profile XPS, providing evidence for the elucidation of a new lattice‐tuning Li+ "layered" deposition‐type SEI structure. At the same time, the SEI is kept from electrolyte erosion fracturing during deposition, resulting in the growth of dendrites along the fracture and significantly enhanced cycling stability under high‐rate cycling conditions. In particular, A‐SEI endows significantly enhanced cycling capability to the full battery at high cycling rate and high current density. The full cell of A‐SEI@Li||LiPF6||LFP exhibits an extended lifetime after 2000 cycles at current densities up to 10 C, and still process a CE above 99.0%. [ABSTRACT FROM AUTHOR]

Fast-charging (high-rate) is a critical need for lithium-ion batteries (LIBs). While superior rate performance can be achieved by nanostructured electrodes, their tap density is often low, which leads to low volumetric energy density and limits their practical applications. Here, we report nanosheet-assembled Li4Ti5O12 (LTO) hierarchical microspheres which can simultaneously achieve high tap density, high rate performance and long cycle life. These microspheres were prepared with high yield by facile solvothermal reaction followed by a short thermal annealing process. The formation mechanism of such LTO microspheres was systematically investigated to understand their morphology evolution and phase transformation process. These well-designed hierarchical microspheres with controlled features on both nanometer- and micrometer-scales enable dense particle packing, easy lithium-ion diffusion and high structure robustness. Optimal LTO microspheres can offer extremely high rate capability (e.g., 155 mAh g−1 at 50 C), and excellent cycling stability (99.5% capacity retention after 2000 cycles at 50 C, 95.4% capacity retention after 3000 cycles at 30 C) with a tap density of 1.32 g cm−3. Furthermore, their superior performance was also demonstrated with LiNi0.5Mn1.5O4 cathode in full cells, which showed 93.4% of capacity retention after 1000 cycles at 3C. These results suggest the great promise of using such high-volumetric-density LTO as an anode material for high-rate and long-life LIBs.

Li4Ti5-xYxO12 (x=0, 0.05, 0.10, 0.15, 0.20) anode materials were synthesized by ball milling assisted solid-state method used Li2CO3 and anatase TiO2 as raw materials and yttrium nitrate (Y(NO3)3·6H2O) as yttrium source. The phase and morphology of the materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS), respectively. The electrochemical performance and transport characteristics of the materials were tested and analyzed by an electrochemical workstation. The results show that there is no effect of Y3+ doping on the spinel structure of LTO material. When x=0.15, the ion and electronic conductivities of the Li4Ti4.85Y0.15O12 sample are 2.68×10-7 S·cm-1 and 1.49×10-9 S·cm-1, respectively, which are an order of magnitude higher than that of the intrinsic LTO, and present good transport characteristics. Electrochemical tests show that a first discharge capacity of Li4Ti4.85Y0.15O12 sample can reach 171 mAh·g-1 at 0.1 C rate. The sample still has a higher specific capacity of 102 mAh·g-1 and 79 mAh·g-1 at a high rate of 10 C and 20 C, respectively.After 200 cycles, the capacity retention rates are 92.6% and 89.1% respectively, showing good magnification characteristics.

Miniaturized energy storage devices with superior performance and compatibility with facile fabrication are highly desired in smart microelectronics. Typical fabrication techniques are generally based on powder printing or active material deposition, which restrict the reaction rate due to the limited optimization of electron transport. Herein, we proposed a new strategy for the construction of high-rate Ni-Zn microbatteries based on a 3D hierarchical porous nickel (Ni) microcathode. With sufficient reaction sites from the hierarchical porous structure as well as excellent electrical conductivity from the superficial Ni-based activated layer, this Ni-based microcathode is featured with fast-reaction capability. By virtue of facile electrochemical treatment, the fabricated microcathode realized an excellent rate performance (over 90% capacity retention when the current density increased from 1 to 20 mA cm−2). Furthermore, the assembled Ni-Zn microbattery achieved a rate current of up to 40 mA cm−2 with a capacity retention of 76.9%. Additionally, the high reactivity of the Ni-Zn microbattery is also durable in 2000 cycles. This 3D hierarchical porous Ni microcathode, as well as the activation strategy, provides a facile route for the construction of microcathodes and enriches high-performance output units for integrated microelectronics. [ABSTRACT FROM AUTHOR]

Zn metal anodes, the key to aqueous zinc‐based energy storage, are plagued by dendrites and sluggish kinetics, which are closely related to the Zn plating process and restricted charge carriers exchange. Herein, a strategy of charge carriers enrichment during Zn plating by employing zincophilic carbon nanotubes (CNTs) on Zn electrodes for dendrite‐free Zn anodes under ultrahigh current density is reported. The CNTs enable an electric double layer to effectively facilitate the enrichment of charge carriers and the refinement of the electric field distribution at the CNTs–Zn interface, displaying unique advantages in enhancing Zn2+ transfer dynamics and planar Zn deposition. The extra capacitive interfacial process boosts Zn deposition kinetics to afford ultrahigh‐rate Zn plating and stripping by decreasing both electrochemical polarization and concentration polarization. As a consequence, reversible Zn stripping and plating at an ultrahigh current density of 50 mA cm−2 and a remarkable discharging depth of 97% are reached. Zn ion hybrid supercapacitors achieve stable cycling at 50 mA cm−2 for 10 000 cycles. This paper offers mechanistic insight for advanced Zn anodes supporting high‐rate charge/discharge with large capacities and enlightens the design of metal anodes. [ABSTRACT FROM AUTHOR]

Li‐metal battery (LMB) suffers from the unexpected Li dendrite growth and unstable solid‐electrolyte interphase (SEI), especially in the extreme conditions, such as high rates and low temperatures (LT). Herein, a high‐rate and stable LT LMB is realized by regulating electrolyte chemistry. A weak Li+‐solvating solvent 2‐methyltetrahydrofuran is used as electrolyte solvent to mitigate the kinetic barrier for Li+ de‐solvation. Moreover, a co‐solvent tetrahydrofuran with a high donor number is incorporated to improve the LT solubility of Li salts, achieving an improved ionic conductivity while maintaining the weak Li+‐solvation effect. Furthermore, abundant FSI‐ anions in contact‐ion pairs are presented, facilitating the formation of a stable LiF‐enriched SEI. Consequently, the Li||Li battery can be operated at 10 mA cm‐2 with a small polarization of 154 mV at −40 °C. Meanwhile, an outstanding cumulative cycling capacity of 4000 mAh cm‐2 at 8.0 mA cm‐2 is achieved, reaching a record high level in LT alkali metal symmetric batteries. Also, rechargeable high‐rate and stable full batteries are achieved at −40 °C. This work demonstrates the superiority of electrolyte chemistry for synergistic regulation of both ion transfer kinetics and SEI toward ultrafast and stable rechargeable LMBs at LT. [ABSTRACT FROM AUTHOR]

Vanadium nitride film made using a thin film deposition technique is a promising electrode material for micro‐supercapacitor applications owing to its high electrical conductivity and high volumetric and surface capacitance values in aqueous electrolyte. Nevertheless, the cycling stability has to be improved to deliver good capacitance during a large number of cycles. Here, it is shown that vanadium nitride films made by a magnetron sputtering deposition method exhibit remarkable cycling stability (high capacitance retention value after 150 000 cycles), ultra‐high rate capability (75% of the initial capacitance at 1.6 V s−1), while providing high surface capacitance values (≈1.4 F cm−2) and very low ageing of the VN electrodes (no loss of performance after 13 months). Additionally, new findings regarding the location of vanadium oxides species responsible for the charge storage mechanism in pseudocapacitive VN films are revealed by transmission electron microscopy electron energy‐loss spectroscopy analyses at the nanoscale. [ABSTRACT FROM AUTHOR]

The cathode materials work as the host framework for both Li+ diffusion and electron transport in Li‐ion batteries. The Li+ diffusion property is always the research focus, while the electron transport property is less studied. Herein, we propose a unique strategy to elevate the rate performance through promoting the surface electric conductivity. Specifically, a disordered rock‐salt phase was coherently constructed at the surface of LiCoO2, promoting the surface electric conductivity by over one magnitude. It increased the effective voltage (Veff) imposed in the bulk, thus driving more Li+ extraction/insertion and making LiCoO2 exhibit superior rate capability (154 mAh g−1 at 10 C), and excellent cycling performance (93 % after 1000 cycles at 10 C). The universality of this strategy was confirmed by another surface design and a simulation. Our findings provide a new angle for developing high‐rate cathode materials by tuning the surface electron transport property. [ABSTRACT FROM AUTHOR]

The cathode materials work as the host framework for both Li+ diffusion and electron transport in Li‐ion batteries. The Li+ diffusion property is always the research focus, while the electron transport property is less studied. Herein, we propose a unique strategy to elevate the rate performance through promoting the surface electric conductivity. Specifically, a disordered rock‐salt phase was coherently constructed at the surface of LiCoO2, promoting the surface electric conductivity by over one magnitude. It increased the effective voltage (Veff) imposed in the bulk, thus driving more Li+ extraction/insertion and making LiCoO2 exhibit superior rate capability (154 mAh g−1 at 10 C), and excellent cycling performance (93 % after 1000 cycles at 10 C). The universality of this strategy was confirmed by another surface design and a simulation. Our findings provide a new angle for developing high‐rate cathode materials by tuning the surface electron transport property. [ABSTRACT FROM AUTHOR]