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Coulombic efficiency of over 99 % is rarely achieved for Li metal anode below −40 °C, hindering the practical application of high‐energy‐density Li metal batteries under extreme conditions. Herein, limiting factors for Li metal reversibility are investigated utilizing ether‐based localized high‐concentration electrolytes of different solvent‐diluent combinations. We find that along with the desolvation barrier, bulk ion transport properties including ionic conductivity, transference number, and diffusivity are also crucial factors for low‐temperature Li deposition behavior. Superior Li metal reversibility was observed within the combination of the solvent with moderately weak solvating power and the diluent with minimal viscosity, highlighting the role of ion transport and the necessity for a trade‐off with desolvation. The optimized electrolyte composed of lithium bis(fluorosulfonyl)imide, methyl n‐propyl ether, and 1,1,2,2‐tetrafluoroethyl methyl ether delivers exceptional Coulombic efficiency of 99.34 % at −40 °C and 98.96 % at −60 °C under a current density of 0.5 mA cm−2. Furthermore, Li||LiCoO2 (2.7 mAh cm−2) cells demonstrate impressive reversible capacity and cycling stability at these temperatures. This work sheds light on the less‐recognized relevance of bulk ion transport to low‐temperature performance and provides guidelines for the electrolyte design of Li metal batteries operating in cold environments. [ABSTRACT FROM AUTHOR]

Improving the wide‐temperature operation of rechargeable batteries is crucial for boosting the adoption of electric vehicles and further advancing their application scope in harsh environments like deep ocean and space probes. Herein, recent advances in electrolyte solvation chemistry are critically summarized, aiming to address the long‐standing challenge of notable energy diminution at sub‐zero temperatures and rapid capacity degradation at elevated temperatures (>45°C). This review provides an in‐depth analysis of the fundamental mechanisms governing the Li‐ion transport process, illustrating how these insights have been effectively harnessed to synergize with high‐capacity, high‐rate electrodes. Another critical part highlights the interplay between solvation chemistry and interfacial reactions, as well as the stability of the resultant interphases, particularly in batteries employing ultrahigh‐nickel layered oxides as cathodes and high‐capacity Li/Si materials as anodes. The detailed examination reveals how these factors are pivotal in mitigating the rapid capacity fade, thereby ensuring a long cycle life, superior rate capability, and consistent high‐/low‐temperature performance. In the latter part, a comprehensive summary of in situ/operational analysis is presented. This holistic approach, encompassing innovative electrolyte design, interphase regulation, and advanced characterization, offers a comprehensive roadmap for advancing battery technology in extreme environmental conditions. [ABSTRACT FROM AUTHOR]

Lithium‐ion batteries are increasingly required to operate under harsh conditions, particularly at high temperatures above 55 °C. However, existing electrolytes suffer from inadequate thermal stability and significant interphasial side reactions. Moreover, there is a lack of clear guidelines for developing electrolytes that can withstand high temperatures. Here a solvent screening descriptor is introduced based on dual local softness and dielectric constant. The findings indicate that solvents with moderate dielectric constants and low reactivity are ideal candidates for high‐temperature electrolytes. Among the solvents evaluated, tetraethyl orthosilicate (TEOS) is identified as a suitable option and is utilized to formulate a localized high‐concentration electrolyte (TEOS‐based LHCE). Remarkably, the 1‐Ah LiNi0.8Co0.1Mn0.1||graphite pouch cell utilizing this TEOS‐based LHCE demonstrates 95.8% capacity retention after 300 cycles at 60 °C. Interphasial analysis reveals that the TEOS‐based LHCE promotes the formation of thin, uniform LiF‐rich interphases, effectively suppressing interfacial side reactions at elevated temperatures. This screening strategy not only enhances the understanding of electrolyte performance but also paves the way for high‐throughput screening of electrolytes suitable for wide‐temperature lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

Stabilizing the electrode interphases is urgently required to enhance the lifetime of high‐voltage sodium‐ion batteries (SIBs). However, the continuous anode solid–electrolyte interphase (SEI) growth associated with electron leakage and the fragile cathode–electrolyte interphase (CEI) lead to capacity fade at high voltage; and yet the solvation‐interphase‐performance relationship is inadequately addressed. Herein, a cooperative Na+‐solvation strategy is reported to stabilize the interphases by a holistic design of electrolytes combining soft and moderate co‐solvents. The rationally regulated Na+‐solvation leads to CEI/SEI with the desired thickness and component stability. As such, remarkable cycling stability is achieved for 4.3‐V Na3V2O2(PO4)2F (NVOPF) cathodes with 83.3% capacity retention over 3000 cycles at 1 C, significantly outperforming the carbonate counterpart (41.6% capacity retention). Meanwhile, the restrained SEI growth via reducing the formation of electron‐leaking Na2CO3 stabilizes the long‐term cycling of the hard carbon (HC) anode. The assembled NVOPF||HC full cells achieve superior rate capability (up to 15 C) and stable cycling stability over 500 cycles. The demonstrated engineering of electrolyte chemistry, Na+‐solvation, and interphase structure/component contributes toward the rational establishment of design rules for high‐voltage SIBs and possibly other similar chemistries. [ABSTRACT FROM AUTHOR]

The practical application of aqueous Zn‐ion batteries (AZIBs) is hindered by the crazy Zn dendrites growth and the H2O‐induced side reactions, which rapidly consume the Zn anode and H2O molecules, especially under the lean electrolyte and Zn anode. Herein, a natural disaccharide, d‐trehalose (DT), is exploited as a novel multifunctional co‐solvent to address the above issues. Molecular dynamics simulations and spectral characterizations demonstrate that DT with abundant polar −OH groups can form strong interactions with Zn2+ ions and H2O molecules, and thus massively reconstruct the coordination structure of Zn2+ ions and the hydrogen bonding network of the electrolyte. Especially, the strong H‐bonds between DT and H2O molecules can not only effectively suppress the H2O activity but also prevent the rearrangement of H2O molecules at low temperature. Consequently, the AZIBs using DT30 electrolyte can show high cycling stability even under lean electrolyte (E/C ratio = 2.95 µL mAh−1), low N/P ratio (3.4), and low temperature (−12 °C). As a proof‐of‐concept, a Zn||LiFePO4 pack with LiFePO4 loading as high as 506.49 mg can be achieved. Therefore, DT as an eco‐friendly multifunctional co‐solvent provides a sustainable and effective strategy for the practical application of AZIBs. [ABSTRACT FROM AUTHOR]

As a promising candidate for the flame‐retardant electrolyte, triethyl phosphate (TEP)/potassium bis(fluorosulfonyl)amide (KFSI)‐based electrolyte has drawn much attention in the K‐ion battery community. Although the TEP/KFSI formula at a moderate main salt concentration (normally, <3 m) enables the compatibility of the reactive K metal anode, the long‐standing oxidative instability of KFSI salt remains unsolved. Here, an additive strategy is reported to address the high‐voltage issue in the TEP/KFSI electrolyte, and generalize it to the other KFSI‐based electrolytes. The addition of potassium nitrate changes the surface charge distribution and effectively suppresses the decomposition of KFSI toward the high‐voltage cathode. The nitrate‐containing electrolyte enables superior stability of a 4.3 V‐class K‐ion battery, as evidenced by its 80% capacity retention over 2000 cycles (≈6 months) at the 1 C rate. Moreover, the long‐cycling stability of the graphite‐based full cell with Prussian Blue cathode is demonstrated. [ABSTRACT FROM AUTHOR]

Promoting homogeneous electrode reactions is crucial for mitigating premature electrode degradation and achieving enhanced cycle stability. This is particularly important for lithium‐metal electrodes that undergo drastic morphological change during electrochemical cycles, as their failure can result in dendritic lithium growth and safety hazards. Extensive prior studies have focused on managing the nano‐/micro‐scale dendritic lithium formations, and proposed the importance of the electrolyte engineering in tailoring the solid‐electrolyte interphase. Herein, this study demonstrates, for the first time, that the macroscale inhomogeneity during lithium plating, comparable to the size of electrode, is also governed by the electrolyte, but, strikingly, this phenomenon stands independent of the propensity of the electrolyte to promote growth of nano‐/micro‐scale lithium dendrites. In situ probe reveals that this electrode‐level inhomogeneity, which occurs irrespective of lithium dendrite formation, is triggered by gas‐generating reactions influenced by the electrolyte composition, and the subsequent gas‐phase (i.e., bubble) evolution causes localized lithium growth. The restricted lithium‐ion mass transport through these bubbles increases the overpotential, which exacerbates the macroscale inhomogeneity, as supported by experimental results and continuum model simulations. The observation of electrolyte‐dependent macroscale lithium inhomogeneity highlights the importance of adopting a multi‐scale perspective when considering control strategies for achieving homogeneity during lithium deposition/stripping processes. [ABSTRACT FROM AUTHOR]

Lithium batteries employing Li or silicon (Si) anodes hold promise for the next‐generation energy storage systems. However, their cycling behavior encounters rapid capacity degradation due to the vulnerability of solid electrolyte interphases (SEIs). Though anion‐derived SEIs mitigate this degradation, the unavoidable reduction of solvents introduces heterogeneity to SEIs, leading to fractures during cycling. Here, we elucidate how the reductive stability of solvents, dominated by the electrophilicity (EPT) and coordination ability (CDA), delineates the SEI formed on Li or Si anodes. Solvents exhibiting lower EPT and CDA demonstrate enhanced tolerance to reduction, resulting in inorganic‐rich SEIs with homogeneity. Guided by these criteria, we synthesized three promising solvents tailored for Li or Si anodes. The decomposition of these solvents is dictated by their EPTs under similar solvation structures, imparting distinct characteristics to SEIs and impacting battery performance. The optimized electrolyte, 1 M lithium bis(fluorosulfonyl)imide (LiFSI) in N‐Pyrrolidine‐trifluoromethanesulfonamide (TFSPY), achieves 600 cycles of Si anodes with a capacity retention of 81 % (1910 mAh g−1). In anode‐free Cu||LiNi0.5Co0.2Mn0.3O2 (NCM523) pouch cells, this electrolyte sustains over 100 cycles with an 82 % capacity retention. These findings illustrate that reducing solvent decomposition benefits SEI formation, offering valuable insights for the designing electrolytes in high‐energy lithium batteries. [ABSTRACT FROM AUTHOR]

Long duration storage batteries such as Redox Flow Batteries (RFBs) are promising storage system to address the energy storage requirement that our society will require in the years to come. Recent effort has been focused on the development of metal free and high energy density system such as all‐organic non‐aqueous redox flow batteries (NAORFBs). However high‐voltage NAORFBs currently use distinct anolytes and catholytes, which are separated by a membrane sensitive to osmotic pressure, resulting in rapid capacity and energy density degradation over time. To address this issue, symmetric organic redox flow batteries (SORFBs) have been proposed as an elegant solution. We have introduced dimethoxyquinacridiniums (DMQA+) ions as efficient bipolar redox molecules (BRMs) in static H‐cell conditions. In this study, we present the first application of DMQA+ ions in a complete flow RFB prototype, showcasing their ability to operate with polarity reversal. Key kinetic properties were evaluated through cyclic voltammetry and DFT calculations. While coulombic and energy efficiency metrics were moderate, pegylated DMQA+ demonstrated impressive capacity retention of over 99.99 % and the capability to operate under polarity inversion, making it a highly attractive choice for grid‐scale, long‐lifespan energy storage applications. [ABSTRACT FROM AUTHOR]

With its efficient nitrogen fixation kinetics, electrochemical lithium‐mediated nitrogen reduction reaction (LMNRR) holds promise for replacing Haber–Bosch process and realizing sustainable and green ammonia production. However, the general interface problem in lithium electrochemistry seriously impedes the further enhancement of LMNRR performance. Inspired by the development history of lithium battery electrolytes, here, we extend the ring‐chain solvents coupling law to LMNRR system to rationally optimize the interface during the reaction process, achieving nearly a two‐fold Faradaic efficiency up to 54.78±1.60 %. Systematic theoretical simulations and experimental analysis jointly decipher that the anion‐rich Li+ solvation structure derived from ring tetrahydrofuran coupling with chain ether successfully suppresses the excessive passivation of electrolyte decomposition at the reaction interface, thus promoting the mass transfer of active species and enhancing the nitrogen fixation kinetics. This work offers a progressive insight into the electrolyte design of LMNRR system. [ABSTRACT FROM AUTHOR]

Abstract The practical application of aqueous Zn‐ion batteries (AZIBs) is hindered by the crazy Zn dendrites growth and the H2O‐induced side reactions, which rapidly consume the Zn anode and H2O molecules, especially under the lean electrolyte and Zn anode. Herein, a natural disaccharide, d‐trehalose (DT), is exploited as a novel multifunctional co‐solvent to address the above issues. Molecular dynamics simulations and spectral characterizations demonstrate that DT with abundant polar −OH groups can form strong interactions with Zn2+ ions and H2O molecules, and thus massively reconstruct the coordination structure of Zn2+ ions and the hydrogen bonding network of the electrolyte. Especially, the strong H‐bonds between DT and H2O molecules can not only effectively suppress the H2O activity but also prevent the rearrangement of H2O molecules at low temperature. Consequently, the AZIBs using DT30 electrolyte can show high cycling stability even under lean electrolyte (E/C ratio = 2.95 µL mAh−1), low N/P ratio (3.4), and low temperature (−12 °C). As a proof‐of‐concept, a Zn||LiFePO4 pack with LiFePO4 loading as high as 506.49 mg can be achieved. Therefore, DT as an eco‐friendly multifunctional co‐solvent provides a sustainable and effective strategy for the practical application of AZIBs.

Highlights A critical assessment of electrolytes’ limiting factors, which affect the low-temperature performance of Li-metal batteries. Summary of emerging strategies to improve low-temperature performance from the aspects of electrolyte design and electrolyte/electrode interphase engineering. Perspectives and challenges on how to develop creative solutions in electrolytes and correlative materials for low-temperature operation.

Highlights The loss mechanisms of irreversible Li in electrolytes with various salts (e.g., lithium hexafluorophosphate (LiPF6), lithium difluoro(oxalato)borate (LiDFOB), and lithium bis(fluorosulfonyl)amide (LiFSI)) are systemically revealed. A universal procedure for the electrolyte design of Li metal batteries is proposed: (i) decouple and find the main reason for the irreversible Li loss; (ii) add the corresponding electrolyte additive.

The discovery and design of versatile high-entropy electrolytes are instrumental in enabling advanced aqueous energy storage devices. Precisely regulating the intermolecular forces of anion-cation, ion-dipole and dipole-dipole, which enhance the microscopic disorder of electrolytes, is the core of high-entropy aqueous electrolyte research. In this perspective, the progress in reshaping the electrolyte structure and constructing high-entropy aqueous electrolytes via additional salt or/and solvent engineering is briefly outlined. Further, the next chapter of high-entropy aqueous electrolyte design and optimization is proposed to provide guidance for the development of future high-performing and multi-functional aqueous batteries.

Highlights: A critical assessment of electrolytes' limiting factors, which affect the low-temperature performance of Li-metal batteries. Summary of emerging strategies to improve low-temperature performance from the aspects of electrolyte design and electrolyte/electrode interphase engineering. Perspectives and challenges on how to develop creative solutions in electrolytes and correlative materials for low-temperature operation. Electrolyte design holds the greatest opportunity for the development of batteries that are capable of sub-zero temperature operation. To get the most energy storage out of the battery at low temperatures, improvements in electrolyte chemistry need to be coupled with optimized electrode materials and tailored electrolyte/electrode interphases. Herein, this review critically outlines electrolytes' limiting factors, including reduced ionic conductivity, large de-solvation energy, sluggish charge transfer, and slow Li-ion transportation across the electrolyte/electrode interphases, which affect the low-temperature performance of Li-metal batteries. Detailed theoretical derivations that explain the explicit influence of temperature on battery performance are presented to deepen understanding. Emerging improvement strategies from the aspects of electrolyte design and electrolyte/electrode interphase engineering are summarized and rigorously compared. Perspectives on future research are proposed to guide the ongoing exploration for better low-temperature Li-metal batteries. [ABSTRACT FROM AUTHOR]

Highlights: The loss mechanisms of irreversible Li in electrolytes with various salts (e.g., lithium hexafluorophosphate (LiPF6), lithium difluoro(oxalato)borate (LiDFOB), and lithium bis(fluorosulfonyl)amide (LiFSI)) are systemically revealed. A universal procedure for the electrolyte design of Li metal batteries is proposed: (i) decouple and find the main reason for the irreversible Li loss; (ii) add the corresponding electrolyte additive. Lithium (Li) metal electrodes show significantly different reversibility in the electrolytes with different salts. However, the understanding on how the salts impact on the Li loss remains unclear. Herein, using the electrolytes with different salts (e.g., lithium hexafluorophosphate (LiPF6), lithium difluoro(oxalato)borate (LiDFOB), and lithium bis(fluorosulfonyl)amide (LiFSI)) as examples, we decouple the irreversible Li loss (SEI Li+ and "dead" Li) during cycling. It is found that the accumulation of both SEI Li+ and "dead" Li may be responsible to the irreversible Li loss for the Li metal in the electrolyte with LiPF6 salt. While for the electrolytes with LiDFOB and LiFSI salts, the accumulation of "dead" Li predominates the Li loss. We also demonstrate that lithium nitrate and fluoroethylene carbonate additives could, respectively, function as the "dead" Li and SEI Li+ inhibitors. Inspired by the above understandings, we propose a universal procedure for the electrolyte design of Li metal batteries (LMBs): (i) decouple and find the main reason for the irreversible Li loss; (ii) add the corresponding electrolyte additive. With such a Li-loss-targeted strategy, the Li reversibility was significantly enhanced in the electrolytes with 1,2-dimethoxyethane, triethyl phosphate, and tetrahydrofuran solvents. Our strategy may broaden the scope of electrolyte design toward practical LMBs. [ABSTRACT FROM AUTHOR]

Alongside the pursuit of high energy density and long service life, the urgent demand for low-temperature performance remains a long-standing challenge for a wide range of Li-ion battery applications, such as electric vehicles, portable electronics, large-scale grid systems, and special space/seabed/military purposes. Current Li-ion batteries suffer a major loss of capacity and power and fail to operate normally when the temperature decreases to −20 ​°C. This deterioration is mainly attributed to poor Li-ion transport in a bulk carbonated ester electrolyte and its derived solid–electrolyte interphase (SEI). In this mini-review discussing the limiting factors in the Li-ion diffusion process, we propose three basic requirements when formulating electrolytes for low-temperature Li-ion batteries: low melting point, poor Li+ affinity, and a favorable SEI. Then, we briefly review emerging progress, including liquefied gas electrolytes, weakly solvating electrolytes, and localized high-concentration electrolytes. The proposed novel electrolytes effectively improve the reaction kinetics via accelerating Li-ion diffusion in the bulk electrolyte and interphase. The final part of the paper addresses future challenges and offers perspectives on electrolyte designs for low-temperature Li-ion batteries.

[Display omitted] As a promising cathode material for high-performance lithium-ion batteries, olivine LiFe 1-x Mn x PO 4 (0 < x < 1, LFMP) combines the high safety of LiFePO 4 and the high energy density of LiMnPO 4. During the charge-discharge process, poor interface stability of active materials leads to capacity decay, which prevents its commercial application. Here, to stabilize the interface, a new electrolyte additive potassium 2-thienyl tri-fluoroborate (2-TFBP) is developed to boost the performance of LiFe 0.3 Mn 0.7 PO 4 at 4.5 V vs. Li/Li+. Specifically, after 200 cycles, the capacity retention remains at 83.78% in the electrolyte containing 0.2% 2-TFBP while the capacity retention without 2-TFBP addition is only 53.94%. Based on the comprehensive measurements results, the improved cyclic performance is attributed to that 2-TFBP has a higher highest occupied molecular orbit (HOMO) energy and its thiophene group can be electropolymerized above 4.4 V vs. Li/Li+ for generating uniform cathode electrolyte interphase (CEI) with poly-thiophene, which can stable materials structure and suppress the decomposition of electrolytes. Meanwhile, 2-TFBP both promotes the deposition/exfoliation of Li+ at anode-electrolyte interfaces and regulates Li deposition by K+ cations through the electrostatic mechanism. This work presents that 2-TFBP has a great application prospect as a functional additive for high-voltage and high-energy-density lithium metal batteries. [ABSTRACT FROM AUTHOR]

Abstract Lithium‐ion batteries (LIBs) with fast‐charging capabilities have the potential to overcome the “range anxiety” issue and drive wider adoption of electric vehicles. The U.S. Advanced Battery Consortium has set a goal of fast charging, which requires charging 80% of the battery's state of charge within 15 min. However, the polarization effects under fast‐charging conditions can lead to electrode structure degradation, electrolyte side reactions, lithium plating, and temperature rise, which are highly linked to the thermodynamic and kinetic properties of electrolytes. The conventional nonaqueous electrolytes used in LIBs consist of carbonate and cannot support fast‐charging without compromising performance and lifespan. This review outlines the challenges of fast‐charging LIBs and the requirements of electrolytes suitable for fast‐charging. Additionally, recent developments in fast‐charging electrolytes from four key perspectives: electrolyte additives, low‐viscosity co‐solvents, high concentration or localized high‐concentration electrolytes, and advanced electrolytes are summarized. Furthermore, this review provides insights for the design of fast‐charging electrolytes based on the mechanism of charging process and offers an overview of the current state and future direction of the field.

Abstract The thermal stability window of current commercial carbonate-based electrolytes is no longer sufficient to meet the ever-increasing cathode working voltage requirements of high energy density lithium-ion batteries. It is crucial to construct a robust cathode–electrolyte interphase (CEI) for high-voltage cathode electrodes to separate the electrolytes from the active cathode materials and thereby suppress the side reactions. Herein, this review presents a brief historic evolution of the mechanism of CEI formation and compositions, the state-of-art characterizations and modeling associated with CEI, and how to construct robust CEI from a practical electrolyte design perspective. The focus on electrolyte design is categorized into three parts: CEI-forming additives, anti-oxidation solvents, and lithium salts. Moreover, practical considerations for electrolyte design applications are proposed. This review will shed light on the future electrolyte design which enables aggressive high-voltage cathodes.

Renewable energy sources have been a topic of ever-increasing interest, not least due to escalating environmental changes. The significant rise of research into energy harvesting and storage over the years has yielded a plethora of approaches and methodologies, and associated reviews of individual aspects thereof. Here, we aim at highlighting a rather new avenue within the field of batteries, the (noaqueous) all-organic redox-flow battery, albeit seeking to provide a comprehensive and wide-ranging overview of the subject matter that covers all associated aspects. This way, subject matter on a historical perspective, general types of redox-flow cells, electrolyte design and function, flow kinetics, and cell design are housed within one work, providing perspective on the all-organic redox-flow battery in a broader sense. [ABSTRACT FROM AUTHOR]

[Display omitted] • A firm and dense SEI layer which can effectively suppress corrosion and hydrogen evolution is successfully in situ constructed on the zinc anode without using organic additive. • The inevitable passivation byproducts are utilized and transformed into the dense in-situ SEI protection layer with superior stability and excellent wettability. • A dynamic electrostatic shielding layer is formed on the uneven and sharp locations of the zinc anode by Y3+ which endows the static in-situ SEI layer with dynamic self-repairing function. The practical application of aqueous Zn-ion batteries (AZIBs) is significantly hindered by the short lifespan and low utilization of zinc metal anodes caused by the notorious hydrogen evolution reaction (HER), corrosion, and dendritic growth. The in-situ formation of a dense Zn-ion conducting solid electrolyte interphase (SEI) is an ideal approach to handle these problems. Herein, we present a twofold-protective strategy involving the dense in-situ SEI layer and the electrostatic shielding layer by incorporating 0.01 M yttrium nitrate (YN) additive into 2 M zinc sulfate electrolyte. The robust oxidizing characteristic of the nitrate induces rapid passivation on the surface of Zn anodes, by which these inevitable passivation byproducts are utilized for in-situ fabricating a dense SEI protection layer with excellent wettability. Besides, the infusion of high-valence rare-earth Y3+ forms a durable, dynamic electrostatic shielding layer around the growth tip of the protuberances. This can regulate Zn2+ deposition and aid in rectifying the irregular and sharp surface on zinc anodes. Benefiting from the synergistic effect of the static film protection and the dynamic electrostatic rectification, zinc anodes exhibit outstanding stability, as evidenced by remarkable cycling lifespan of exceeding 2000 h at 1 mAh cm−2 and 600 h at 10 mAh cm−2 in Zn symmetric cells and the preeminent CE of 99.83 % with stably cycling over 2200 times in half-cells at 4 mA cm−2. This study reveals a straightforward yet pragmatic avenue of synergistic dual-protection effect to achieve anti-corrosion and dendrite-free Zn anodes. [ABSTRACT FROM AUTHOR]

Olivine-type lithium iron manganese phosphate (LFMP) combines the high energy density of LiMnPO 4 with the high safety of LiFePO 4 , is considered to be one of the most promising cathode materials for the next generation. However, the Mn dissolution behavior due to the Jahn-Teller effect of Mn3+ irreversibly causes loss of active material during electrochemical cycling, accompanied by severe capacity decay and structural degradation, which is more severe at elevated temperature. Herein, in order to enhance the cycling performance of LFMP cathode material, the cathode-electrolyte interface is stabilized by inducing bis(oxalate)borate (LiBOB) decomposition electrochemically to form a CEI layer. Specifically, the capacity retention of the battery in the electrolyte containing 0.75 wt% LiBOB is 95.37 % after 200 cycles at 25 °C and 1C. (1C = 170 mA g−1) The capacity retention is 89.17 % after 200 cycles at 55 °C and 1C, compared to only 72 % in the electrolyte without LiBOB. The superior cycling performance is attributed to the formation of a uniform CEI layer induced by LiBOB electrochemically, which inhibits the parasitic reaction between the cathode and electrolyte, reduces the dissolution of Mn in the active substance, enabling superior and safer cycling performance even at elevated temperature. [Display omitted] • Rational use of molecular structural features to design electrode interfaces. • The CEI layer is formed on the surface of cathode by electrochemically induced. • The CEI layer suppresses parasitic reaction at the cathode-electrolyte interface. • The presence of the CEI layer enhances high temperature performance. [ABSTRACT FROM AUTHOR]

• 0-D and 1-D electrochemical models for the Li-S battery are offered. • The effect of the E/S ratio on discharge performance is predicted. • The impact of electrolyte properties on discharge performance is projected. • 0-D model is less sensitive than 1-D model in terms of the predicted capacity. Herein, we offer two electrochemical models, a zero-dimensional (0-D) and a one-dimensional (1-D) model, to mechanistically explore the impact of the electrolyte-to-sulfur (E/S) ratio and electrolyte properties on the discharge behavior of a lithium-sulfur (Li-S) cell. The electrochemically active area in both models is defined based on the carbon weight fraction and reference porosity, so the influence of the carbon loading and E/S ratio on the reaction kinetics is included. Mass transfer of the species must be considered to model the reliance of the discharge capacity on the current density. Instead, the 0-D model is more responsive to the influence of the E/S ratio on the discharge capacity. The effect of electrolyte properties can be modeled implicitly through model parameters. The 0-D model is less sensitive to the variance in model parameters than the 1-D model in terms of the predicted capacity. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • VO 2 (B), VO 2 (M), and VO 2 (A) are synthesized and their properties are investigated. • ZnSO 4 -based aqueous electrolyte with various concentrations of LiTFSI is developed. • Solvation structures of electrolytes are studied using wide-angle X-ray scattering. • The correlation between solution structures and electrolyte properties is examined. • Operando TXM observations confirm high dimensional stability of VO 2 during cycling. Three VO 2 polymorphs, namely monoclinic VO 2 (B), monoclinic VO 2 (M), and tetragonal VO 2 (A), are synthesized, and their microstructures and electrochemical properties are studied for application in Zn-ion batteries (ZIBs). A cost-effective ZnSO 4 -based aqueous electrolyte with various concentrations (3 − 7 m) of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) additive is developed. The optimal ZnSO 4 /LiTFSI ratio in the electrolyte for superior Zn//VO 2 battery properties is examined. The coordination structures of various electrolytes are investigated using wide-angle X-ray scattering. The incorporation of LiTFSI impairs the hydrogen-bonded network of H 2 O molecules and causes solvated-TFSI and TFSI‧‧‧TFSI structures to form, altering the electrolyte properties (such as electrochemical stability window, ionic conductivity, and Zn(OH) 2) 3 (ZnSO 4)· x H 2 O byproduct formation tendency). It is found that an excessive LiTFSI concentration leads to the formation of ion aggregates in the electrolyte and thus deterioration of electrode specific capacity and rate capability. Operando transmission X-ray microscopy observations confirm the high dimensional stability of the VO 2 cathode during charging and discharging; the length variation of the VO 2 (B) rods is approximately 10 %. The electrolyte composition also affects the Zn2+/Zn redox behavior at the anode side. The incorporation of LiTFSI into the electrolyte affects the Zn plating/stripping Coulombic efficiency, morphology of the deposited Zn, dead Zn amount, and anode cycle life. The constructed Zn//VO 2 (B) cell with 1 m ZnSO 4 /5 m LiTFSI dual-salt electrolyte shows 90 % capacity retention after 1000 cycles. The proposed electrode material and electrolyte composition have great potential for applications in high-performance and high-stability rechargeable ZIBs. [ABSTRACT FROM AUTHOR]

Highlights: A critical assessment of cathode–electrolyte interphase (CEI) for high-voltage cathode electrodes in Li-ion cells. Fundamental understanding of why interfacial interphase is important to electrochemical performance and further elaboration on how to design robust CEI interphase. Emerging theoretical simulations and advanced in situ characterizations helps to unveil the mystery of CEI are summarized.The thermal stability window of current commercial carbonate-based electrolytes is no longer sufficient to meet the ever-increasing cathode working voltage requirements of high energy density lithium-ion batteries. It is crucial to construct a robust cathode–electrolyte interphase (CEI) for high-voltage cathode electrodes to separate the electrolytes from the active cathode materials and thereby suppress the side reactions. Herein, this review presents a brief historic evolution of the mechanism of CEI formation and compositions, the state-of-art characterizations and modeling associated with CEI, and how to construct robust CEI from a practical electrolyte design perspective. The focus on electrolyte design is categorized into three parts: CEI-forming additives, anti-oxidation solvents, and lithium salts. Moreover, practical considerations for electrolyte design applications are proposed. This review will shed light on the future electrolyte design which enables aggressive high-voltage cathodes. [ABSTRACT FROM AUTHOR]

Zinc–iron redox flow batteries (ZIRFBs) possess intrinsic safety and stability and have been the research focus of electrochemical energy storage technology due to their low electrolyte cost. This review introduces the characteristics of ZIRFBs which can be operated within a wide pH range, including the acidic ZIRFB taking advantage of Fen+ with high solubility, the alkaline ZIRFB operating at a relatively high open-circuit potential and current densities, and the neutral ZIRFB providing a non-toxic, harmless, and mild environment. No matter what kind of ZIRFB, there are always zinc dendrites limiting areal capacity on the anode, which has become an obstacle that must be considered in zinc-based RFBs. Therefore, we focus on the current research progress, especially the summarizing and analysis of zinc dendrites, Fe(III) hydrolysis, and electrolytes. Given these challenges, this review reports the optimization of the electrolyte, electrode, membrane/separator, battery structure, and numerical simulations, aiming to promote the performance and development of ZIRFBs as a practical application technology. Based on these investigations, we also provide the prospects and development direction of ZIRFBs. [ABSTRACT FROM AUTHOR]

Solid-state polyether electrolytes formed by in-situ ring-opening polymerization (ROP) of 1,3-dioxolane (DOL) have attracted great attention due to their high lithium-ion conductivity, and good interface compatibility. However, DOL ring-opening polymerization is difficult to control, resulting in the formation of poly(1,3-dioxolane) (PDOL) with high molecular weight and high crystallinity, which hinder Li + diffusion and deteriorate the interfacial contact. Herein, trimethylsilyl isocyanate (IPTS) was introduced into DOL ring-opening system as a moisture eliminating agent to weaken the Li salt-based initiating system and regulate the polymerization process. Based on this, the resultant PDOL electrolytes with 3 wt.% IPTS exhibit ionic conductivity of 2.8×10 -4  S cm -1 , a high Li + transference number (0.68) and excellent stability with Li anode. The Li|PDOL-3 %IPTS|Li battery exhibits a stable cycling performance for more than 1100 h under 0.5 mA cm -2 and 0.5 mAh cm -2 . Furthermore, the LiFePO 4 |PDOL-3 %IPTS|Li cell shows a capacity retention rate of 89.2 % after 200 cycles (25 °C, 1 °C) and 94.5 % (60 °C, 1 °C) after 500 cycles, which is much higher than that of PDOL (6.6 %) after 70 cycles (25 °C, 1 °C). This work provides guidance for the manipulation of ROP process further to enhance the performance of solid-state lithium metal batteries., (© 2024 Wiley-VCH GmbH.)

Lithium metal batteries paired with high-voltage LiNi 0.5 Mn 1.5 O 4 (LNMO) cathodes are a promising energy storage source for achieving enhanced high energy density. Forming durable and robust solid-electrolyte interphase (SEI) and cathode-electrolyte interface (CEI) and the ability to withstand oxidation at high potentials are essential for long-lasting performance. Herein, advanced electrolytes are designed via trio-functional additives to carbonate-based electrolytes for 5 V Li||LNMO and graphite||LNMO cells achieving 88.3% capacity retention after 500 charge-discharge cycles. Theoretical calculations reveal that adding adiponitrile facilitates the presence of more hierarchical DFOB - and PF 6 - dual anion structure in the solvation sheath, leading to a faster de-solvation of the Li cation. By combining both fluorine and nitrile additives, an efficient synergistic effect is obtained, generating robust thin inorganic SEI and CEI films, respectively. These films enhance microstructural stability; Li dendrite growth on the Li electrode is being suppressed at the anode side and transition-metals dissolution from the cathode is being mitigated, as evidenced by cryo-transmission electron microscopy and synchrotron studies., (© 2024 The Author(s). Advanced Materials published by Wiley‐VCH GmbH.)

Advancing grid-scale energy storage technologies is crucial for realizing a fully renewable energy landscape, with non-aqueous redox flow batteries (NRFBs) presenting a promising solution. One of the current challenges in NRFBs stems from the low energy density of redox active materials, primarily due to their limited solubility in non-aqueous solvents. Herein, this study explores the solubility of vanadium(IV/V) bis-hydroxyiminodiacetate (VBH) crystals in acetonitrile, aiming to use them as anionic catholytes in NRFBs. We focused on enhancing VBH solubility by modifying the structure of the alkylammonium cation. Employing periodic density functional theory and a solvation model, we calculated the dissolution free energy ([[EQUATION]]), which includes sublimation ([[EQUATION]]) and solvation ([[EQUATION]]) energies. Our results indicate that neither elongating straight-chain alkyl groups beyond a tetrabutylammonium baseline nor introducing bulky substituents at the nitrogen center significantly enhances solubility. However, the introduction of carbon spacers combined with terminal bulky substituents markedly improves solubility by favorably altering both [[EQUATION]] and [[EQUATION]]. These findings underline the nuanced impact of cation structure on solubility and suggest a viable approach to optimize VBH-based anionic catholytes. This advancement promises to enhance NRFB efficiency and sustainability, marking a significant step forward in energy storage technology., (© 2024 Wiley‐VCH GmbH.)

Silicon (Si) is one of the most promising anode materials for high-energy lithium-ion batteries. However, the widespread application of Si-based anodes is inhibited by large volume change, unstable solid electrolyte interphase, and poor electrical conductivity. During the past decade, significant efforts have been made to overcome these major challenges toward industrial applications. This review summarizes the recent development of microscale Si-based electrodes fabricated by Si microparticles or other industrial bulk materials from the perspective of industrialization. First, the challenges for microscale Si anodes are clarified. Second, structural design strategies of stable micro-sized Si materials are discussed. Third, other critical practical metrics, such as robust binder construction and electrolyte design, are also highlighted. Finally, future trends and perspectives on the commercialization of Si-based anodes are provided.

Aqueous zinc‐ion batteries (ZIBs) are promising next‐generation battery system which can mitigate the prevailing issues on the conventional lithium‐ion batteries. However, insufficient energy density with low operating voltage prevents the practical utilization of the aqueous system. Notably, aqueous ZIBs suffer from electrolyte decomposition due to its narrow electrochemical stability window (ESW) for 1.23 V. Also, studies on cathode active materials that store charge at an elevated voltage region is still in the initial stage. In this perspective, we cover the recent strategies for developing high‐voltage aqueous ZIBs. First, electrolyte designs for expanding the ESW of an aqueous electrolyte are introduced based on their characterization, materials, and working mechanisms. Next, we propose the cathode active materials with high‐working voltage. Furthermore, studies on zinc anodes are also briefly presented. Lastly, we summarize the as‐reported strategies and provide insight for developing future ZIBs. [ABSTRACT FROM AUTHOR]

Lithium metal is considered as an ideal anode material for next-generation high energy density batteries with its high specific capacity and low electrode potential. However, the high activity of lithium metal can lead to a series of safety issues. For example, lithium metal will continuously react chemically with the electrolyte, forming unstable the solid electrolyte (SEI) films. In addition, lithium dendrites can be formed during cycling, which can puncture the SEI film and cause short circuits in the battery. These drawbacks greatly hinder the commercial application of lithium metal. To solve the above problems, it is important to understand the structure of SEI and the underlying mechanism of its formation as a guide for rational design. Quantum mechanics (QM) has been demonstrated as an effective tool to investigate the chemical reactions and microscopic atomic structures of SEI. However, QM is computationally too expensive to be used for large-scale and long-term theoretical simulations. Instead, the molecular mechanics (MM) method has much orders higher computational efficiency than QM, and can be used for large-scale and long-time theoretical simulations. However, the accuracy of MM is usually not guaranteed, especially for complex SEI. Therefore, a practical solution is to combine the advantages of both. In this work, we use the hybrid ab initio and reactive molecule dynamics (HAIRs) approach to describe chemical reactions with the accuracy of quantum chemistry and improve the computational efficiency by more than 10 times with mixing QM and MM. Using this method, we have investigated the interfacial reaction mechanism of two electrolyte solutions, 1 mol⋅-1 LiTFSI-DME (dimethoxyethane) and 1 mol⋅-1 LiTFSI-EC (ethylene carbonate) with the lithium metal anode. The simulation results show that TFSI anion prefers to be decomposed, while DME does not, thus, TFSI plays the vital role of protecting DME. However, in the LiTFSI-EC system, both TFSI anion and EC are decomposed, indicating that EC is less stable and not suitable to the formation of stable SEI. Thanks to the computational efficiency of the HAIRs method, we have completed the 1 ns simulation in a few days. Using the hardware, the above calculation would take at least one to two months if only the QM method was employed. Meanwhile the long HAIRs calculation shows that for the simulation of chemical reactions in SEI, at least 1 ns is essential. Instead, previous molecular dynamics (MD) simulations with a few ps, or tens of ps, are insufficient to fully capture the critical chemical reactions. The above simulation results provide reliable experience for the computational simulation study of SEI formation, and lay the theoretical foundation for the rational design of electrolytes and the development of high-performance electrolyte solution systems. [ABSTRACT FROM AUTHOR]

Governments and research & development (R&D) organizations are actively initiating various programs and research strategies for CO 2 capture, its utilization, and integration with long duration energy storage from renewable sources worldwide. In line with the carbon capture goals, here we report a novel electrochemical Al-CO 2 battery cell, that can simultaneously capture CO 2 and convert it into value-added products, in addition to long-duration energy generation and storage. This innovative approach employs cost-effective Al metal as an anode and an in-house synthesized Ni–Fe based bimetallic double hydroxide catalyst as the cathode, with meticulously optimized compositions and morphologies. We explore the impact of different aqueous electrolyte solutions compositions on the cell performance, demonstrating up to 10 h of stable long duration energy storage with a stable voltage profile. The cell exhibits low polarization even at high current densities of up to 12 mA cm−2 and maintains stable cycling over 500 h. Through Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray Diffraction and X-ray photoelectron spectroscopy (XPS) analysis, we determined that the discharge product is either NaAlCO 3 (OH) 2 or KAlCO 3 (OH) 2 , distinct from the Al 2 (CO 3) 3 typically reported in conventional Al–CO 2 batteries. [Display omitted] • Sequestration of CO 2 and energy generation in aqueous single chamber battery system. • Metal-CO 2 battery for long duration energy system. • Aqueous Al–CO 2 battery is different than the nonaqueous Al–CO 2 system. • Aluminum salt solution is very much pH sensitive for precipitation production. [ABSTRACT FROM AUTHOR]

Redox flow batteries have received wide attention for electrochemical energy conversion and storage devices due to their specific advantage of uncoupled power and energy devices, and therefore potentially to reduce the capital costs of energy storage. Terrific structural features of polyoxometalates exhibit unique advantages in redox flow batteries, such as, stable chemical properties, multi-electron reaction, good redox reversibility, low permeability, etc, which furnishes a novel perspective for settling various problems of redox flow batteries. This was a comprehensive and critical review of this type of batteries, focusing mainly on the chemistry of polyoxometalate electrolyte materials and introducing a systematic classification. Finally, challenges and perspectives of polyoxometalate electrolyte materials and polyoxometalate redox flow batteries are discussed.

Entropy, once overlooked, is an essential aspect of electrolytes. Recently emerged high-entropy electrolytes with multiple components provide vast compositional space and interfacial chemistry possibilities for electrolyte design. It is noteworthy that high-entropy electrolytes exhibit extraordinarily high ionic conductivity at low temperatures, thereby creating a new direction for batteries to operate at ultra-low temperatures. This commentary discusses the underlying mechanism, challenges encountered, and potential solutions of high-entropy electrolyte design in the hope of sparking future research in this subject.

In situ polymerized solid-state electrolytes have attracted much attention due to high Li-ion conductivity, conformal interface contact, and low interface resistance, but are plagued by lithium dendrite, interface degradation, and inferior thermal stability, which thereby leads to limited lifespan and severe safety hazards for high-energy lithium metal batteries (LMBs). Herein, an in situ polymerized electrolyte is proposed by copolymerization of 1,3-dioxolane with 1,3,5-tri glycidyl isocyanurate (TGIC) as a cross-linking agent, which realizes a synergy of battery thermal safety and interface compatibility with Li anode. Functional TGIC enhances the electrolyte polymeric level. The unique carbon-formation mechanism facilitates flame retardancy and eliminates the battery fire risk. In the meantime, TGIC-derived inorganic-rich interphase inhibits interface side reactions and promotes uniform Li plating. Intrinsically safe LMBs with nonflammability and outstanding electrochemical performances under extreme temperatures (130 °C) are achieved. This functional polymer design shows a promising prospect for the development of safe LMBs., (© 2024 Wiley‐VCH GmbH.)

Given the limitations inherent in current intercalation‐based Li‐ion batteries, much research attention has focused on potential successors to Li‐ion batteries such as lithium–sulfur (Li‐S) batteries and lithium–oxygen (Li‐O2) batteries. In order to realize the potential of these batteries, the use of metallic lithium as the anode is essential. However, there are severe safety hazards associated with the growth of Li dendrites, and the formation of "dead Li" during cycles leads to the inevitable loss of active Li, which in the end is undoubtedly detrimental to the actual energy density of Li‐metal batteries. For Li‐metal batteries under practical conditions, a low negative/positive ratio (N/P ratio), a electrolyte/cathode ratio (E/C ratio) along with a high‐voltage cathode is prerequisite. In this Review, we summarize the development of new electrolyte systems for Li‐metal batteries under practical conditions, revisit the design criteria of advanced electrolytes for practical Li‐metal batteries and provide perspectives on future development of electrolytes for practical Li‐metal batteries. [ABSTRACT FROM AUTHOR]

Electrolyte recipes and Li metal anode host materials are developed for lithium-metal batteries. 1,2-dimethoxyethane/ethylene carbonate mixed solvent with 1 M lithium bis(fluorosulfonyl)imide and 1 wt% LiNO 3 is shown to form a robust solid electrolyte interphase and improve Coulombic efficiency and cyclability during Li metal plating/stripping. This electrolyte can withstand high potential, allowing the operation of a LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NMC-811) cathode. One-dimensional carbon nanotubes, two-dimensional graphene nanosheets, and three-dimensional ordered mesoporous carbon CMK-8 are used as the host materials for the accommodation of Li metal. The strong and continuous conducting network of CMK-8 with interpenetrating open channels is found to be a promising scaffold for Li metal. With the proposed electrolyte, the CMK-8 electrode enables uniform Li plating/stripping with a high Coulombic efficiency of 99.2% under a practical current density of 1 mA cm−2. Moreover, a long life of >550 charge-discharge cycles is achieved. The high structural stability of CMK-8 upon cycling is confirmed using electron microscopy and Raman spectroscopy. Finally, we use a Li-free CMK-8 electrode, an NMC-811 cathode, and the proposed electrolyte to construct a full cell. The electrochemical properties are evaluated. [Display omitted] • Electrolyte and anode host materials are developed for lithium-metal batteries. • The proposed electrolyte induces a robust SEI and withstands high potential. • 1-D CNT, 2-D graphene, and 3-D CMK-8 carbon host materials are examined. • CMK-8 structure can minimize the dead Li amount and suppress Li dendrite formation. • Superior CE of 99.2% and great stability of up to 550 cycles are found for CMK-8. [ABSTRACT FROM AUTHOR]

Renewable energy sources have been a topic of ever-increasing interest, not least due to escalating environmental changes. The significant rise of research into energy harvesting and storage over the years has yielded a plethora of approaches and methodologies, and associated reviews of individual aspects thereof. Here, we aim at highlighting a rather new avenue within the field of batteries, the (noaqueous) all-organic redox-flow battery, albeit seeking to provide a comprehensive and wide-ranging overview of the subject matter that covers all associated aspects. This way, subject matter on a historical perspective, general types of redox-flow cells, electrolyte design and function, flow kinetics, and cell design are housed within one work, providing perspective on the all-organic redox-flow battery in a broader sense.

Zinc–iron redox flow batteries (ZIRFBs) possess intrinsic safety and stability and have been the research focus of electrochemical energy storage technology due to their low electrolyte cost. This review introduces the characteristics of ZIRFBs which can be operated within a wide pH range, including the acidic ZIRFB taking advantage of Fen+ with high solubility, the alkaline ZIRFB operating at a relatively high open-circuit potential and current densities, and the neutral ZIRFB providing a non-toxic, harmless, and mild environment. No matter what kind of ZIRFB, there are always zinc dendrites limiting areal capacity on the anode, which has become an obstacle that must be considered in zinc-based RFBs. Therefore, we focus on the current research progress, especially the summarizing and analysis of zinc dendrites, Fe(III) hydrolysis, and electrolytes. Given these challenges, this review reports the optimization of the electrolyte, electrode, membrane/separator, battery structure, and numerical simulations, aiming to promote the performance and development of ZIRFBs as a practical application technology. Based on these investigations, we also provide the prospects and development direction of ZIRFBs.

Machine learning (ML) approaches have the potential to create a paradigm shift in science, especially for multi‐variable problems at different levels. Modern battery R&D is an area intrinsically dependent on proper understanding of many different molecular level phenomena and processes alongside evaluation of application level performance: energy, power, efficiency, life‐length, etc. One very promising battery technology is Li−S batteries, but the polysulfide solubility in the electrolyte must be managed. Today, many different electrolyte compositions and concepts are evaluated, but often in a more or less trial‐and‐error fashion. Herein, we show how supervised ML can be applied to accurately classify different Li−S battery electrolytes a priori based on predicting polysulfide solubility. The developed framework is a combined density functional theory (DFT) and statistical mechanics (COSMO‐RS) based quantitative structure‐property relationship (QSPR) model which easily can be extended to other battery technologies and electrolyte properties. [ABSTRACT FROM AUTHOR]

High-concentration KFSI EC/DEC electrolyte enables great rate performance of graphite anode and KMO cathode. The electrolyte constructs a unique anion-solvent co-derived SEI. [Display omitted] • High-concentration KFSI EC/DEC electrolyte enables great rate performance of KMO and graphite. • The electrolyte constructs a unique anion-solvent co-derived SEI. • The reconstructed cell tests demonstrate the importance of solvation structure and SEI to the rate performance of graphite anode. The system of layered-metal-oxide||carbon-anode cells with carbonate electrolytes is highly promising for constructing potassium-ion batteries (PIBs). However, this system faces serious issues of poor compatibility between the electrolyte and electrode, particularly with conventional ethylene carbonate (EC)-based electrolytes. Herein, owing to the regulated coordination environment of cation–anion-solvent and the formed KF-rich interface, a superior rate performance of graphite anode was achieved. The designed 4 M KFSI EC/DEC electrolyte demonstrates superior performance in graphite||K cells, exhibiting a high reversible capacity of approximately 200 mAh g−1 at a high current density of 700 mA g−1, surpassing many reported high-concentration and weak solvation PIB electrolytes. Meanwhile, it exhibits low polarization and maintains stable contact stability with active K metal. Furthermore, it demonstrates great compatibility with Mn-based layered metal oxide cathodes. Remarkably, we reveal a unique formation mechanism of the solvent-anion co-derived solid electrolyte interface (SEI) through a two-stage XPS deep analysis, which has the KF-deficient inorganic inner and KF-rich outer. This SEI can protect the graphite structure and enable great rate performance of graphite anode. This work holds significant reference value for the design of commercial electrolytes. [ABSTRACT FROM AUTHOR]

[Display omitted] By introducing a minute quantity of phytate ammonium into the conventional dilute zinc sulfate electrolyte, a static physical barrier is established by the phytic anion. Simultaneously, a dynamic electrostatic shield layer collaborates, yielding superior electrochemical performance. This addition facilitates an accelerated de-solvation process, effectively suppressing the so-called "tip effect" and mitigating dendrite growth. • Developed facile and effective additives for aqueous zinc-ion batteries. • Utilized both cation and anion for a multi-functional additive. • Physical barrier and dynamic electrostatic-field shield layer enhance performance. • Realized a dual protection mechanism for high performance. Corrosion and the formation of by-products resulting from parasitic side reactions, as well as random dendrite growth, pose significant challenges for aqueous zinc-ion batteries (AZIBs). In this study, phytate ammonium is introduced into the traditional dilute Zinc sulfate electrolyte as a multi-functional additive. Leveraging the inherent zincophilic nature of the phytic anion, a protective layer is formed on the surface of the zinc anode. This layer can effectively manipulate the deposition process, mitigate parasitic reactions, and reduce the accumulation of detrimental by-products. Additionally, the competitive deposition between dissociated ammonium ions and Zn2+ promotes uniform deposition, thereby alleviating dendrite growth. Consequently, the modified electrolyte with a lower volume addition exhibits superior performance. The zinc symmetric battery demonstrates much more reversible plating/stripping, sustaining over 2000 h at 5 mA cm−2 and 1 mA h cm−2. A high average deposition/stripping efficiency of 99.83 % is achieved, indicating the significant boosting effect and practical potential of our strategy for high-performance aqueous zinc-ion batteries. [ABSTRACT FROM AUTHOR]

The implementation of Li-based liquid metal batteries (LMBs) for grid-scale energy storage has been limited by the high cost of materials, especially for fabrication of Li-halide based molten salt electrolytes (e.g., LiCl, LiBr, LiF, LiI). This study aims to determine the impact of incorporating lower cost alkali/alkaline earth halide salts with foreign cations (e.g., Sr2+, K+) into a Li-based molten salt electrolyte to build a foundation for continued LMB electrolyte design and development. The widely reported LiF–LiCl–LiBr (22-31-47 mol%, T m = 430–443 °C) electrolyte is used within the Li || Sb–Sn LMB system as a baseline from which to compare the performance of similar systems with eutectic salts of LiCl–SrCl 2 (64.3–35.7 mol%, T m = 489 °C) and LiCl–KCl (59.2–40.8 mol%, T m = 352 °C) with a specific focus on the positive Sb–Sn electrode in a 3-electrode cell. While good chemical reversibility was maintained for the Li || Sb–Sn systems with mixed-cation molten salts, a shift in the electroactive species from Li + to Sr2+ limited the capacity of the LMB system with a LiCl–SrCl 2 electrolyte and reduced rate capability was observed for the LiCl–KCl containing system. • Studied the impact of mixed-cation electrolytes on Sb–Sn electrode performance. • Performance maintained for LiCl–KCl system at low current density. • Limited rate capability observed for LiCl–KCl system at high current density. • LiCl–SrCl 2 electrolyte resulted in Sr as the dominant electroactive species. [ABSTRACT FROM AUTHOR]

High-energy-density lithium-metal batteries (LMBs) coupling lithium-metal anodes and high-voltage cathodes are hindered by unstable electrode/electrolyte interphases (EEIs), which calls for the rational design of efficient additives. Herein, we analyze the effect of electron structure on the coordination ability and energy levels of the additive, from the aspects of intramolecular electron cloud density and electron delocalization, to reveal its mechanism on solvation structure, redox stability, as-formed EEI chemistry, and electrochemical performances. Furthermore, we propose an electron reconfiguration strategy for molecular engineering of additives, by taking sorbide nitrate (SN) additive as an example. The lone pair electron-rich group enables strong interaction with the Li ion to regulate solvation structure, and intramolecular electron delocalization yields further positive synergistic effects. The strong electron-withdrawing nitrate moiety decreases the electron cloud density of the ether-based backbone, improving the overall oxidation stability and cathode compatibility, anchoring it as a reliable cathode/electrolyte interface (CEI) framework for cathode integrity. In turn, the electron-donating bicyclic-ring-ether backbone breaks the inherent resonance structure of nitrate, facilitating its reducibility to form a N-contained and inorganic Li 2 O-rich solid electrolyte interface (SEI) for uniform Li deposition. Optimized physicochemical properties and interfacial biaffinity enable significantly improved electrochemical performance. High rate (10 C), low temperature (-25 °C), and long-term stability (2700 h) are achieved, and a 4.5 Ah level Li||NCM811 multilayer pouch cell under harsh conditions is realized with high energy density (462 W h/kg). The proof of concept of this work highlights that the rational ingenious molecular design based on electron structure regulation represents an energetic strategy to modulate the electrolyte and interphase stability, providing a realistic reference for electrolyte innovations and practical LMBs.

Many studies are focused on the development of materials for converting carbon dioxide into multicarbon oxygenates such as methanol and ethanol, because of their higher energy density and wider applicability. In this work, TiO2 nanotubes (NT/TiO2) were modified with CuxO nanoparticles in order to investigate the contribution of different ratio of Cu2O/CuO and its distribution over NT/TiO2 for CO2 photoelectro-conversion to methanol. The photoelectrodes were built by anodization process to obtain NT/TiO2 layer, and the decoration with CuxO hybrid system was carried out by electrodeposition process, using Na2SO4 or acid lactic as electrolyte, followed by annealing at different temperatures. X-ray photoelectron spectroscopy analysis revealed the predominance of Cu+1 and Cu+2 at 150 °C and 300 °C, respectively. X-ray diffraction and scanning electron microscopy indicated that under lactic acid solution, the oxide nanoparticles exhibited small size, cubic shape, and uniform distribution on the nanotube wall. While under Na2SO4 electrolyte, large nanoparticles with two different morphologies, octahedral and cubic shapes, were deposited on the top of the nanotubes. All modified electrodes converted CO2 in methanol in different quantities, identified by gas chromatograph. However, the NT/TiO2 modified with CuO/Cu2O (80:20) nanoparticles using lactic acid as electrolyte showed better performance in the CO2 reduction to methanol (0.11 mmol L−1) in relation to the other electrodes. In all cases, a blend among the structures and nanoparticle morphologies were achieved and essential to create new site of reactions what improved the use of light irradiation, minimization of charge recombination rate and promoted high selectivity of products. [ABSTRACT FROM AUTHOR]

Rechargeable aluminum batteries (RABs) are extensively developed due to their cost‐effectiveness, eco‐friendliness, and low flammability and the earth abundance of their electrode materials. However, the commonly used RAB ionic liquid (IL) electrolyte is highly moisture‐sensitive and corrosive. To address these problems, a 4‐ethylpyridine/AlCl3 IL is proposed. The effects of the AlCl3 to 4‐ethylpyridine molar ratio on the electrode charge–discharge properties are systematically examined. A maximum graphite capacity of 95 mAh g−1 is obtained at 25 mA g−1. After 1000 charge–discharge cycles, ≈85% of the initial capacity can be retained. In situ synchrotron X‐ray diffraction is employed to examine the electrode reaction mechanism. In addition, low corrosion rates of Al, Cu, Ni, and carbon‐fiber paper electrodes are confirmed in the 4‐ethylpyridine/AlCl3 IL. When opened to the ambient atmosphere, the measured capacity of the graphite cathode is only slightly lower than that found in a N2‐filled glove box; moreover, the capacity retention upon 100 cycles is as high as 75%. The results clearly indicate the great potential of this electrolyte for practical RAB applications. [ABSTRACT FROM AUTHOR]