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The escalating demand for sustainable energy storage solutions, driven by the depletion of fossil fuels has stimulated extensive research in advanced battery technologies. Over the past two decades, global primary energy consumption, initially satisfied by non‐renewables, has raised environmental concerns. Despite the availability of renewable sources like solar and wind, storage challenges propel innovation in batteries. Lithium‐ion batteries (LIBs) have gained recognition for their high energy density and cost‐effectiveness. However, issues such as safety concerns, dendrite formation, and limited operational temperatures necessitate alternative solutions. A promising approach involves replacing flammable liquid electrolytes with non‐flammable solid electrolytes (SEs). SEs represent a transformative shift in battery technology, offering stability, safety, and expanded temperature ranges. They effectively mitigate dendrite growth, enhancing battery reliability and lifespan. SEs also improve energy density, making them crucial for applications like portable gadgets, electric vehicles, and renewable energy storage. However, challenges such as ionic conductivity, chemical and thermal stability, mechanical strength, and manufacturability must be addressed. This review paper briefly identifies SE types, discusses their advantages and disadvantages, and explores ion transport fundamentals and all‐solid‐state batteries (ASSBs) production challenges. It comprehensively analyzes sulfide SEs (SSEs), focusing on recent advancements, chemical and electrochemical challenges, and potential future improvements. Electrochemical reactions, electrolyte materials, compositions, and cell designs are critically assessed for their impact on battery performance. The review also addresses challenges in ASSB production. The objective is to provide a comprehensive understanding of SSEs, laying the groundwork for advancing sustainable and efficient energy storage systems. [ABSTRACT FROM AUTHOR]

In scanning electrochemical microscopy (SECM), the addition of a redox active species plays an essential role. Those deliberately added mediators may alter results in SECM studies. In investigations of lithium‐ion battery (LIB) materials, especially of the positive electrode, the oxidation potentials of commonly used mediator substances such as ferrocene are located within the operation potential of the electrode. Thus, they possibly interfere with the regular charge/discharge processes. In situ studies are therefore in need of approaches reducing or eliminating the use of mediators. Within this publication, a novel mediator dosing (MD) concept is introduced. A capillary was closely positioned at the tip of the scanning probe. By gravity flow, stable flow rates of mediator solution of up to 32.4±0.6 μL h−1 were achieved. These low amounts were found to be sufficient to form a ferrocene zone at the probe tip enabling feedback mode SECM measurements with comparable quality to measurements directly in ferrocene solution. Proof of concept experiments were conducted by investigation of a thin‐film electrode with a micro‐structured surface. Furthermore, the MD concept was applied in imaging experiments of a commercially available LIB graphite electrode. [ABSTRACT FROM AUTHOR]

The Li‐rich antifluorite‐type oxides Li5FeO4, Li5.5Fe0.5Co0.5O4 and Li6CoO4 have been investigated as positive electrode materials for Li‐ion batteries in a combined operando XANES and XRD experiment. All materials show a similar two‐step behaviour upon initial charge (termed Stage I and Stage II), and reversibility of subsequent cycling depends upon whether the initial charge cycle is terminated following Stage I or allowed to proceed through Stage II. By tracking the energetic evolution of the XANES pre‐edge feature present in both Fe and Co K‐edge spectra, as well as the evolution of X‐ray diffractograms during charge and discharge, we correlate the changes in chemical coordination and oxidation states in both species and the structural changes to the electrochemical potential profile, and infer the role of anionic redox processes. [ABSTRACT FROM AUTHOR]

Conjugated sulfonamides (CSAs) stand out for their propitious electroactivity and notable stability in ambient conditions, making them suitable candidates for high‐potential cathode materials in lithium‐ion batteries (LIBs). This study employs a combination of machine learning, semi‐empirical quantum mechanics, and density functional theory methods to evaluate a large library of 11 432 CSA molecules, focusing on material properties crucial for application in batteries, such as synthetic complexity, redox potential, gravimetric charge capacity, and energy density. After applying the thresholds for the synthetic complexity score at 2.62 and the redox potential at 3.25 V versus Li/Li+, we identify 50 CSA molecules that are easy to synthesize and suitable for the positive electrode in LIBs. By ranking on the basis of redox potential, 13 CSA molecules having potentials greater than 3.50 V versus Li/Li+ are identified. Through further investigations using molecular dynamics simulations on these reactant molecules and their lithiated products, a molecule is singled out for synthesis and electrochemical evaluation. This molecule, lithium (2,5‐dicyano‐1,4‐phenylene)bis((methylsulfonyl)amide)(Li2‐DCN‐PDSA), demonstrates a redox potential surpassing those previously reported within the class of CSA molecules. Moreover, the study explores the quantitative structure‐property relations of CSAs, yielding insights for the development of CSA‐based LIB cathode materials, informed by the comprehensive data assembled. [ABSTRACT FROM AUTHOR]

The intermittent nature of renewable energy generation can be tackled by integrating them with electrochemical energy storage, which can also close the gap between supply and demand effectively. It has recently been demonstrated that Si3N4‐based negative electrodes are a promising option for lithium‐ion batteries due to their large theoretical capacity and appropriate working potential with extremely low polarization. In the present work, Si3N4 was utilized as anode material in all‐solid‐state lithium‐ion battery with lithium borohydride as a solid electrolyte and Li foil placed as a counter electrode. The electrochemical properties were investigated using galvanostatic charge/discharge profiling whereas the mechanism of lithiation delithiation was investigated in detail using x‐ray diffraction (XRD). The highest capacity of the composite materials was obtained as 1700 mAhg−1 at 0.05 C current rate in the first cycle, which is reduced to 370 in 5 cycles. However, a stability in the capacity was observed in subsequent cycles and a retention of almost 88% could be achieved in 150 cycles. The interfacial resistance before and after the electrochemical cycling was observed as 326 Ω and 13 kΩ, respectively which is also supported by the microstructural investigations where the cracks are observed because of thermochemical reactions. [ABSTRACT FROM AUTHOR]

Si has been considered as an appealing anode material for high-performance lithium-ion batteries due to its high theoretical capacity. However, the large volume variation limits its practical application. Herein, a binder-, conductive additive- and current collector-free Si/reduced graphene oxide film has been constructed via a simple thermal-reduction method. In the film, Si nanoparticles are encapsulated by reduced graphene oxide, which can accommodate the volume change of Si during cycling efficiently. When utilized as a negative electrode, the Si/reduced graphene oxide film has displayed a high reversible capacity of 1733.4 mAh g−1 after 50 cycles at 200 mA g−1. Importantly, the electrochemical impedance spectroscopy results suggest that the composite film possesses more efficient electrochemical reaction kinetics. The strategy reported in this work may supply a facile preparation route for other metal or metal oxides/reduced graphene oxide films. [ABSTRACT FROM AUTHOR]

For the purpose of predicting the state of health of already used lithium-ion batteries from 85 kWh electric vehicles, a simplified equivalent circuit model is utilized to estimate the electrochemical time constant from constant current discharge profiles. The grading process among as-obtained LIB cells is classified into three level types according to the remaining capacity and direct current resistance. Theoretically, the logarithmic equation describing cycling behavior is derived and utilized in the prediction of the state of health of the used cells. After the selection of the electrochemical time constant obtained from the best-fitting results in constant current discharge data, the suitable cycle number until the 20th cycle was selected for the prediction of the state of health after the 250th cycling data, which revealed that a narrow error range below 5% was for high and medium battery grades. Also, this error range became abruptly wider in lowest grade batteries, indicating that our proposed model for cycling behavior was highly useful in the prediction of the future state of health of the used batteries. [ABSTRACT FROM AUTHOR]

Separators are of significance in the thermal safety and energy‐storage performance of lithium‐ion batteries. Polyimide (PI) separators have great prospects as membrane candidate materials due to their high thermal and chemical stability. Here, a series of PI lithium‐ion battery membranes containing benzonorbornene and pyridine were prepared by using polyethylene glycol (PEG) or polyvinylpyrrolidone (PVP) as pore‐forming agents. The obtained porous polymer membrane PI‐PEG600 had excellent thermal stability (initial weight‐loss temperature up to 300°C and Tg of 278°C), satisfying liquid electrolyte uptakes (up to 132.65%), and admirable ionic conductivity (1.62 × 10−4 S cm−1). The battery with PI porous membranes showed greatly enhanced electrochemical performance with high C‐rate discharge capability (167.3–108.8 mAh g−1, 0.1–2 C) and excellent capacity of 155.6 mAh g−1 at 0.2 C after 55 cycles, meanwhile, it could work steadily at 180°C. This work offers a feasible and effective route to develop membranes of heat‐resistant PI separators for safe lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

Rechargeable aqueous Zn ion batteries (AZIBs) have attracted significant attention as a promising alternative to Li‐ion batteries due to the use of water‐based electrolytes, high energy density per volume, and cost‐effectiveness. However, various parasitic reactions relating to hydrogen evolution reaction, corrosion, and dendrite growth in the Zn anode can result in the degradation of the electrochemical performance of AZIBs. Therefore, understanding the mechanisms underlying these various phenomena and their role in the electrochemical performance of AZIBs provides valuable insights for the development of anode and cathode materials. In this study, we investigate the effect of the MnO2 cathode and Al2O3‐coated Zn anode on the electrochemical performance of the AZIBs. The experimental results show that Al2O3‐coated Zn anodes efficiently suppress the dendrite growth on the Zn. However, significant cycling fade of the full cell comprising of an Al2O3‐coated Zn anode and MnO2 cathode was observed during continuous charge/discharge cycles. The poor cycle performance can be mainly attributed to the phase transformation of MnO2–Mn2O3 and the formation of various byproducts, which highlights the importance of the electrochemical stability of cathode materials in AZIBs to improve the cycle performance. [ABSTRACT FROM AUTHOR]

With society's rapid progress, there is an increasing need for electricity among individuals, but the prevailing source of electricity is still mainly obtained through the burning of nonrenewable fossil fuels, which are not renewable and pose serious environmental hazards. Lithium-ion batteries are used widely for excellent rechargeable capabilities and high energy density. Recently, researchers have become increasingly interested in transition metal sulfides owing to their cost-effectiveness and remarkable specific capacity. However, their commercialization has been hindered by the expansion of material volume and low electrical conductivity during charging and discharging. We have successfully designed and synthesized MoS2 nanosheets loaded on carbon spheres with a 3D hollow structure starting from SiO2 as a template. Due to the doping of carbon materials and particular 3D hollow structures, the optimal C/MoS2-0.3 hollow nanocomposites exhibit excellent electrochemical performance. Following exposure to over 900 cycles at a 0.5 A g-1 ampere density, the materials exhibited an exceptional 958.50 mAh g-1 reversible capacity, demonstrating their remarkable performance. [ABSTRACT FROM AUTHOR]

Aluminum foil is a typical cathode collector in lithium‐ion batteries, yet it encounters various issues, including restricted contact with the active substance, poor adhesion, and regional corrosion associated with the electrolyte. Although conventional carbon‐coated aluminum foils partially alleviate such problems, they suffer from excess weight and thickness of their carbon layers. Here a simple casting method to prepare Ketjen Black/aqueous graphene dispersion slurry modified aluminum foil (KB‐AGD‐Al‐CCs) and graphene micro‐sheets/aqueous graphene dispersion slurry modified aluminum foil (GM‐AGD‐Al‐CCs). Our results indicate that batteries utilizing graphene‐modified aluminum foils exhibited superior electrochemical performance compared with that of carbon‐coated aluminum foils. The lithium‐ion battery employing GM‐AGD‐Al‐CCs as cathode current collectors exhibits reversible specific capacities of 155, 118, and 92.5 mAh/g at current densities of 0.1, 5, and 10 C. After cycling for 1800 cycles at 5 and 10 C, its specific capacities remain at 91 and 77.5 mAh/g. Combing contact angle measurement, electrical conductivity test with electrochemical impedance spectroscopy indicates that the graphene coating decreases the contact angle between the commercial LiFePO4 and current collector, increases the electrical conductivity of the electrode and adhesion. Moreover, the inclusion of GM and KB as conductive additives compensates for graphene's low interlayer conductivity by forming a conductive network. [ABSTRACT FROM AUTHOR]

Li–S batteries are positioned as a strong alternative for efficient energy storage due to their high theoretical energy density and their theoretical specific capacity (1675 mA h g−1) compared to current Li-ion batteries; however, their commercialization is affected by the rapid decay of the specific capacity as a consequence of the different species of lithium polysulfides that are generated during the charge–discharge processes. The use of nitrogen-doped mesoporous carbon materials has been shown to have the ability to confer electronic conductivity to sulfur and retain the lithium polysulfide species. However, there are not enough studies to help understand how the type of nitrogen precursor influences the development of specific nitrogen functionalities to favor the retention of lithium polysulfide species. This work seeks to determine the effect of the use of different nitrogen precursors on the structural changes of the mesoporous carbon materials prepared, and thus evaluate the electrochemical behavior of Li–S cells correlating the type of nitrogen functionality generated when the precursor is variated with the charge/discharge capacity developed during the cell operation. For this study, different carbon materials were prepared by the variation of the nitrogen source (melamine, ethylenediamine, and hexadecylamine) to obtain a N-doped mesoporous carbon with different distributions of nitrogen functionalities in its structure. The use of the primary amine ethylenediamine as a nitrogen precursor in the formation of structured carbon materials favored elemental sulfur infiltration into its pores, resulting in the maximum sulfur content within the pores and interacting with the carbonaceous matrix (78.8 wt.%). The carbon material prepared with this precursor resulted in a higher content of N-pyridinic functionality, which, combined with the high content of N-pyrrolic, resulted in the highest specific discharge capacity at 0.1 C after 100 cycles when compared to cells assembled with materials derived from the use of melamine and hexadecylamine precursors. The cell assembled with the electrode formed from ethylenediamine as a nitrogen precursor presented an initial discharge capacity of 918 mA h g−1 with a Coulombic efficiency of ~83.4% at 0.1 C after 100 cycles. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Electrochemistry is the property of Journal of Electrochemistry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract In scanning electrochemical microscopy (SECM), the addition of a redox active species plays an essential role. Those deliberately added mediators may alter results in SECM studies. In investigations of lithium‐ion battery (LIB) materials, especially of the positive electrode, the oxidation potentials of commonly used mediator substances such as ferrocene are located within the operation potential of the electrode. Thus, they possibly interfere with the regular charge/discharge processes. In situ studies are therefore in need of approaches reducing or eliminating the use of mediators. Within this publication, a novel mediator dosing (MD) concept is introduced. A capillary was closely positioned at the tip of the scanning probe. By gravity flow, stable flow rates of mediator solution of up to 32.4±0.6 μL h−1 were achieved. These low amounts were found to be sufficient to form a ferrocene zone at the probe tip enabling feedback mode SECM measurements with comparable quality to measurements directly in ferrocene solution. Proof of concept experiments were conducted by investigation of a thin‐film electrode with a micro‐structured surface. Furthermore, the MD concept was applied in imaging experiments of a commercially available LIB graphite electrode.

Carbonyl rich conjugated polymer electrode materials for lithium‐ion batteries possessed the advantages of strong molecular design ability, abundance and high theoretical capacity. In this work, a Co2+ coordinated conjugated polymer using 2,3,5,6‐tetraamino‐p‐benzoquinone (TABQ) as building block was constructed and developed as electrode material for all organic symmetric lithium‐ion batteries, outputting a specific capacity of over 100 mAh g−1 after 50 cycles at 50 mA g−1. Performances of Co‐TABQ in half cells were explored. The Co‐TABQ cathode delivered a capacity of 133.3 mAh g−1 after 150 cycles at 20 mA g−1. When cycled at higher current density of 500 mA g−1, the capacity gradually increased to 109.4 mAh g−1 after 4000 cycles. The Co‐TABQ anode displayed a stable capacity of 568.6 mAh g−1 at 1 A g−1. The charge transfer within the electrode was greatly reduced due to the metallic centers in the extended conjugated skeleton, and the reversible Li+ storage was achieved by the active C=O and imine groups. This work showed the great potential of metal mediated conjugated polymer in Lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

GeFe2O4 (GFO) is a germanium mineral whose spinel crystal structure determines its interesting functional properties. Recently, it was proposed for application as an anode for Sodium and Lithium-Ion Batteries (SIBs and LIBs) thanks to its combined conversion and alloying electrochemical mechanism. However, its entire potential is limited by the poor electronic conductivity and volumetric expansion during cycling. In the present paper, pure and Sn or Mg doped GFO samples obtained from mechano-chemical solid-state synthesis and properly carbon coated were structurally and electrochemically characterized and proposed, for the first time, as anodes for SIBs. The spinel cubic structure of pure GFO is maintained in doped samples. The expected redox processes, involving Fe and Ge ions, are evidenced in the electrochemical tests. The Sn doping demonstrated a beneficial effect on the long-term cycling (providing 150 mAh/g at 0.2 C after 120 cycles) and on the capacity values (346 mAh/g at 0.2 C with respect to 300 mAh/g of the pure one), while the Mg substitution was less effective. [ABSTRACT FROM AUTHOR]

This paper investigates the effect of water content on lithium-ion battery electrolytes with particular emphasis on the degradation of lithium hexafluorophosphate, a commonly used salt in commercial electrolytes. The study addresses various degradation mechanisms caused by water in a battery system. In addition, the research utilizes electrochemical techniques to detect water and associated changes in electrochemical performance of the cell. The electrochemical water detection method investigated is very fast. The lower detection limit was not tested, but contamination of 250 ppm can be reliably detected. It can be used, for example, in experimental research to determine the purity and quality of the electrolyte used. [ABSTRACT FROM AUTHOR]

Deeper understanding of processes involved in operation of lithium‐ion batteries (LIBs) is necessary to further optimize them for future applications. Extensive research was conducted on the formation of a solid electrolyte interphase (SEI) on negative battery electrodes, still leaving several questions unanswered. Scanning probe microscopies (SPMs) enable in situ and operando investigations and have the potential to explain some phenomena. Scanning electrochemical microscopy (SECM) and scanning ion conductance microscopy (SICM) could be employed in LIB studies. A novel SICM method based on the redox couple ferrocene/ferrocenium is introduced for applications in carbonate solvents widely used in LIBs. Proof of concept measurements were conducted with a micro milled copper circuit board as model substrate. Furthermore, the proposed SICM approach was hyphenated with feedback mode SECM resulting in the simultaneous mapping of morphology and electrochemical activity. A flexible dual‐probe arrangement was developed enabling usage of both SPM techniques at the same time, and furthermore, an easy replacement of both individual probes if needed. The setup was applied in the characterisation of commercial graphite electrodes for LIBs before and after conducting a pre‐charging protocol. Changes in electrochemical activity and topography of the graphite electrode were resolved in simultaneously generated SECM/SICM recordings. [ABSTRACT FROM AUTHOR]

LiNi0.5Mn1.5O4 (LNMO) is a promising positive electrode material for high‐energy‐density lithium‐ion batteries (LIBs) because of its high working voltage; however, its practical application is hindered by the insufficient oxidation resistance of LIB electrolytes. In this study, we aimed to address this issue by evaluating two trifluoromethylated lithium borate compounds lithium difluoro (perfluoropinacolato) borate (PFP‐F2) and lithium difluoro(2‐hydroxy‐3,3,3,3′,3′,3′‐hexafluoroisobutylato) borate (HHIB‐F2) as electrolyte salts for high‐potential LIBs (4.8 V vs. Li/Li+) with LNMO positive electrodes. In full‐cell tests, the cyclability of LIBs containing these salts is superior (60 °C) to that of the cell with lithium tetrafluoroborate (LiBF4) as the reference electrolyte salt, which is ascribed to the formation of a positive electrode passivation layer that inhibits the oxidative decomposition of the electrolyte salt and solvent in the former case. Moreover, the oxidative decomposition of trifluoromethylated borates at 4.8 V affords a passivation layer on the negative electrode. Thus, the examined borates hold great promise for the commercialization of high‐energy‐density LNMO‐based LIBs, and the formation of a solid electrolyte interphase (SEI) at the negative electrode resulting from the oxidative decomposition products of electrolyte salts is a promising new way to enhance the performance of high‐potential positive electrode LIBs beyond existing levels. [ABSTRACT FROM AUTHOR]

The rapid uptake of lithium ion batteries (LIBs) for large scale electric vehicle and energy storage applications requires a deeper understanding of the degradation mechanisms. Capacity fade is due to the complex interplay between phase transitions, electrolyte decomposition and transition metal dissolution; many of these poorly understood parasitic reactions evolve gases as a side product. Here we present an on‐chip electrochemistry mass spectrometry method that enables ultra‐sensitive, fully quantified and time resolved detection of volatile species evolving from an operating LIB. The technique's electrochemical performance and mass transport is described by a finite element model and then experimentally used to demonstrate the variety of new insights into LIB performance. We show the versatility of the technique, including (a) observation of oxygen evolving from a LiNiMnCoO2 cathode and (b) the solid electrolyte interphase formation reaction on graphite in a variety of electrolytes, enabling the deconvolution of lithium inventory loss (c) the first direct evidence, by virtue of the improved time resolution of our technique, that carbon dioxide reduction to ethylene takes place in a lithium ion battery. The emerging insight will guide and validate battery lifetime models, as well as inform the design of longer lasting batteries. [ABSTRACT FROM AUTHOR]

Zinc-ion batteries (ZIBs) show incredible potential as an alternative to lithium-ion batteries (LIBs) in energy storage applications. ZIBs have multiple advantages, such as safety, environmental friendliness, low cost, and natural abundance, that could be a potential alternative to LIBs. This mini-review summarizes the basics of aqueous ZIBs (AZIBs). The current market for ZIBs is briefly discussed, along with the companies expected to take part in maximizing the benefits of AZIBs in the near future. In addition, the novel chemistry of ZIBs is presented based on the components of AZIBs, such as the cathode, anode, and electrolyte materials. Despite the advantages of AZIBs, they still face some challenges, such as finding a suitable cathode material with better structural stability and excellent electrochemical performance. Finally, the challenges and possible future outlooks are summarized. [ABSTRACT FROM AUTHOR]

The use of graphene oxide (GO) has shown potential in improving the performance of redox flow lithium‐ion batteries (RFLIBs). These types of batteries use a liquid electrolyte containing redox‐active species to store and release energy. Despite being scalable, RFLIBs face limitations, namely, low energy density of the electrolyte and reduced cycling stability of the electrodes. However, GO's unique properties, such as its high conductivity as well as large surface area, create an attractive option for enhancing the electrochemical properties of both the electrolyte and electrodes in RFLIBs. When used as an electrode, GO improves the kinetic reversibility reactions, leading to increased electrochemical activity towards redox couples. Charge transfer resistances of positive and negative reactions are reduced, leading to increased voltage energy and efficiency of lithium batteries in terms of energy usage. As redox flow batteries made of lithium ions are an established subsystem and a growing research and development field, there is potential to enhance their performance and reduce costs through the use of GO. The objective of this review is to provide an overview of the chemistry of GO as it pertains to RFLIBs use, covering topics such as its surface chemistry, functionalization, and interactions with redox‐active species, as well as its potential for enhancing high‐density storage of electricity in batteries. Specifically, it will discuss the impact of GO on redox reactions in the electrolyte, including its ability to raise the redox‐active species concentration as well as enhance their stability. The review will also examine how GO impacts the electrodes, including its potential to increase their surface area and conductivity and promote cycling stability. Additionally, the review will address the importance of optimizing the quantity and distribution of GO in both the electrolyte and electrodes of RFLIBs. [ABSTRACT FROM AUTHOR]

Path dependency in ageing of Lithium‐ion batteries (LIBs) still needs to be fully understood, and gaps remain. For realistic operational scenarios that involve dynamic load profiles, understanding this path dependency is essential for effective monitoring and accurate modelling of LIBs‐ageing. Our research investigates the impact of different ageing sequences on capacity reduction and resistance increase, key metrics for determining the state of health (SOH). Moreover, we argue that relying solely on SOH‐based monitoring is insufficient for predicting the ongoing ageing trajectory. Our findings underscore that recent operational history influences subsequent degradation. This degradation is attributed to the emergence of uneven lithium distribution, which can both induce capacity recovery and amplify degradation during cycling phases. Such insights are particularly interesting for ageing studies where accelerated battery degradation is achieved through continuous cycling, a common approach in most cyclic ageing investigations. We demonstrate that capacity difference analysis (CDA) holds promise in tracking this unevenness and the potential for capacity restoration through re‐homogenisation. In conclusion, our work highlights the importance of utilising advanced tools, such as CDA and degradation mode (DM) analysis, to ensure accurate conclusions are drawn in accelerated LIB‐ageing experiments. [ABSTRACT FROM AUTHOR]

Heteroatom‐doped porous carbons have stable structures, high electron/ion transport efficiencies, and rich electroactive sites, which are of great significance to energy storage devices. The potential synergistic effects arising from the multi‐element doping benefit to improve the electrochemical behavior of porous carbon. In this paper, a facile doping strategy has been proposed to prepare the (N, Co, Zr, P) tetra‐doped porous carbon spheres (PCS) for enhanced lithium‐ion batteries (LIBs). The metal‐organophosphine framework (MOPF) as precursor is synthesized by utilizing riboflavin sodium phosphate as organic ligand coordinating with cobalt and zirconium ions. Through carbonizing MOPF, the (N, Co, Zr, P) tetra‐doped PCS can be obtained. As the anode for LIBs, the (N, Co, Zr, P) tetra‐doped PCS exhibits highly reversible capacity of 761 mAh g−1 at 0.1 A g−1 after 100 cycles, excellent rate performance of 126 mAh g−1 even at a high current density of 2 A g−1. The results feature that the unique 3D structure and superior local electron transport properties of (N, Co, Zr, P) tetra‐doped PCS promote the Li+ diffusion and adsorption, which improve the electrochemical properties. Moreover, the mechanism analysis realizes that the Li+ storage of (N, Co, Zr, P) tetra‐doped PCS is determined by the capacitive behavior at high scan rate, highlighting the significance of the heteroatom doping. Therefore, the (N, Co, Zr, P) tetra‐doped PCS should be considered as prominent candidate for high‐performance LIBs anodes. [ABSTRACT FROM AUTHOR]

Abstract Deeper understanding of processes involved in operation of lithium‐ion batteries (LIBs) is necessary to further optimize them for future applications. Extensive research was conducted on the formation of a solid electrolyte interphase (SEI) on negative battery electrodes, still leaving several questions unanswered. Scanning probe microscopies (SPMs) enable in situ and operando investigations and have the potential to explain some phenomena. Scanning electrochemical microscopy (SECM) and scanning ion conductance microscopy (SICM) could be employed in LIB studies. A novel SICM method based on the redox couple ferrocene/ferrocenium is introduced for applications in carbonate solvents widely used in LIBs. Proof of concept measurements were conducted with a micro milled copper circuit board as model substrate. Furthermore, the proposed SICM approach was hyphenated with feedback mode SECM resulting in the simultaneous mapping of morphology and electrochemical activity. A flexible dual‐probe arrangement was developed enabling usage of both SPM techniques at the same time, and furthermore, an easy replacement of both individual probes if needed. The setup was applied in the characterisation of commercial graphite electrodes for LIBs before and after conducting a pre‐charging protocol. Changes in electrochemical activity and topography of the graphite electrode were resolved in simultaneously generated SECM/SICM recordings.

For the purpose of predicting the state of health of already used lithium-ion batteries from 85 kWh electric vehicles, a simplified equivalent circuit model is utilized to estimate the electrochemical time constant from constant current discharge profiles. The grading process among as-obtained LIB cells is classified into three level types according to the remaining capacity and direct current resistance. Theoretically, the logarithmic equation describing cycling behavior is derived and utilized in the prediction of the state of health of the used cells. After the selection of the electrochemical time constant obtained from the best-fitting results in constant current discharge data, the suitable cycle number until the 20th cycle was selected for the prediction of the state of health after the 250th cycling data, which revealed that a narrow error range below 5% was for high and medium battery grades. Also, this error range became abruptly wider in lowest grade batteries, indicating that our proposed model for cycling behavior was highly useful in the prediction of the future state of health of the used batteries.

The prosperity of the lithium‐ion battery market is dialectically accompanied by the depletion of corresponding resources and the accumulation of spent batteries. It is an urgent priority to develop green and efficient battery recycling strategies for helping ease resources and environmental pressures at the current stage. Here, we propose a mild and efficient lithium extracting strategy based on potential controllable redox couples. Active lithium in the spent battery without discharging is extracted using a series of tailored aprotic solutions comprised of polycyclic aromatic hydrocarbons and ethers. This ensures a safe yet efficient recycling process with nearly ≈100 % lithium recovery. We further investigate the Li+‐electron concerted redox reactions and the effect of solvation structure on kinetics during the extraction, and broaden the applicability of the Li‐PAHs solution. This work can stimulate new inspiration for designing novel solutions to meet efficient and sustainable demands in recycling batteries. [ABSTRACT FROM AUTHOR]

Niobium tungsten oxide is a potential replacement for graphite in fast‐charge lithium‐ion batteries due to its high rate performance and high stability. Herein, Nb14W3O44 anode was synthesized by hydrothermal reaction of niobium oxalate and ammonium tungstate and sequent calcination of niobium tungsten oxide precursors. Compared with the traditional solid‐state method, the particle size and calcination time of Nb14W3O44 obtained by the modified method are greatly reduced. Through orthogonal experiments, the optimal synthesis conditions were determined, and it was found that hydrothermal conditions have an important influence on the particle size of the final product, while the calcination temperature and time greatly affect the purity of the product and thus influence its specific capacity during cycles. [ABSTRACT FROM AUTHOR]

In‐depth analyses, including discharge behaviour, electrochemical impedance analysis, and for the first time, nonlinear frequency response analysis, are conducted on the ageing of negative electrodes with varying particle size distribution. The electrode‐resolved analysis is used to distinguish the kinetic and transport losses at the respective electrodes. For fine to medium‐sized particles at the negative electrode, ageing impacts are found more on the positive electrode: the impedance and nonlinear responses increase, suggesting that the charge transfer process at the positive electrode is worsened. Meanwhile, for coarse and broad negative particles, the impedance and nonlinear responses at negative electrodes decrease due to improved kinetics from micro‐cracking. The second harmonic reveals a change in the nature of the charge transfer during ageing: the charge transfer process at the positive electrode becomes asymmetric for fine and medium‐sized negative particles. Vice versa, the charge transfer process at the negative electrode becomes symmetric for coarse and broad negative particles. [ABSTRACT FROM AUTHOR]

Tin (Sn) is an emerging anode candidate for Li-ion batteries. Due to its high availability and low cost, researchers are studying Sn anode as a next-generation anode alternative for Li-ion batteries (LIB). In this study, we have investigated the electroplated Sn anode obtained from the aqueous media. We have utilized the electrodeposition method for synthesizing pure tin anode on the copper current collector. Aqueous media comprised of tin salt, surface activator, adhesive agent, buffering, and the complexing agent was utilized for obtaining pure tin without using any binder and a conductive agent. Deposition potentials and their effect on the particle morphology and crystal structure were investigated. To enhance the electrochemical performance, we coated the tin anode with the conducting polymer coating and further analyzed the effect of the heat treatment on the polymer-coated tin anodes. The electrochemical performance and physicochemical properties of the electrodeposited Sn electrode were characterized by, Scanning electron microscopy, X-ray Diffraction, and electrochemical techniques. As the voltage of the coating potential increases, it has been observed that the tin particles further enlarge. No difference is observed in X-ray diffraction results for the tin electrodes obtained at different voltages. Coating voltage values of -0.8V and - 0.9V have provided ideal electrochemical results. Although polymer coating has a positive effect on the initial capacity value, it has been observed that it does not have sufficient improvement in cycle life. [ABSTRACT FROM AUTHOR]

An accurate estimation of the residual energy, i. e., State of Energy (SoE), for lithium‐ion batteries is crucial for battery diagnostics since it relates to the remaining driving range of battery electric vehicles. Unlike the State of Charge, which solely reflects the charge, the SoE can feasibly estimate residual energy. The existing literature predominantly focuses on showcasing diverse methods with a gap in conducting in‐depth analysis and comparison of the SoE. The scope of this work is to provide a comprehensive understanding of the SoE by discussing the feasibility and applicability of various definitions and estimation approaches from the literature. For the first time, we classify existing SoE definitions, considering the differences between the inherent stored and usable energy. In the absence of a unified definition in the literature, we propose two physically feasible definitions. Based on the proposed definitions, we critically analyze the practical challenges of SoE estimation. Additionally, to examine the accuracy of the most suitable SoE definition, we conduct an experimental evaluation using a commercial NCA/C+Si cell. Compared to the State of stored Energy, we demonstrate that the State of Charge underestimates the residual energy by more than 3 %, highlighting the importance of adequate SoE estimation. [ABSTRACT FROM AUTHOR]

The use of reference electrodes (REs) in lithium‐ion batteries allows enhanced electrochemical analysis of individual electrodes via potential monitoring or electrochemical impedance spectroscopy (EIS). The previous publication presents a concept for a laser‐perforated RE (PRE). Herein, this PRE is applied in ≈60 mAh graphite/NMC811 pouch cells. Despite more than 17% of the electrode surface being covered by the PRE, only negligible capacity differences are observed for charge rates up to 2C compared to cells without PRE. At higher rates up to 5C, the blocking effect is present but stable. Reproducible and plausible anode voltage curves are obtained and the beginning of Li plating is detected. Cell EIS spectra are in good agreement with comparison cells without RE. The impedance spectra of the individual electrodes recorded by the PRE are confirmative and, with one exception, artifact‐free. The results demonstrate that our PRE can be reliably applied for investigating lab‐scale electrode coatings in small pouch cell formats. [ABSTRACT FROM AUTHOR]

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Aqueous cells have gained widespread attention for their low‐cost and safety. However, the 1.23 V thermodynamic stability window of water severely limits their development and application. To solve this issue, this study proposes and demonstrates that regulators can enhance and protect water molecules through hydrogen bond reconstruction and assist in solid electrolyte interface generation. The expanded electrochemical window enables the construction of aqueous symmetric capacitors and Nb18W16O93||LiMn2O4 aqueous lithium‐ion batteries with voltages both up to 2.6 V, while exhibiting considerable Coulombic efficiency and high cycle stability. It is shown that efficient regulation of interaction and electrochemical window can also be achieved by a regulator alone, without relying on the effect of salt itself or the extreme reduction of water content. This not only provides a simple and effective way to develop aqueous cells, but also provides a new understanding for the research and utilization of H‐bonds and intermolecular interactions in water. [ABSTRACT FROM AUTHOR]

Dual‐ion batteries (DIBs) with graphite as cathode material, show superiority in terms of sustainability, affordability, and environmental impact over Li‐ion batteries that rely on transition‐metal based cathodes. However, graphite cathodes severely suffer from poor structural stability during anion storage at high potentials because of the co‐intercalation and oxidative decomposition of electrolytes. This work presents an in situ electrochemistry‐driven route to create a bifunctional interphase through implantation of diethylenetriaminepenta(methylene‐phosphonic acid) (DTPMP) on the surface of graphite particles. The reaction mechanisms and functions of DTPMP are investigated both experimentally and theoretically. The DTPMP‐derived interphase not only improves the antioxidative stability of electrolytes but also benefits the desolvation of PF6− anions, which doubly protect the graphitic structure and give rise to fast‐charge and ultralong cycling performance of graphite cathodes in DIBs. [ABSTRACT FROM AUTHOR]

Nickel‐rich layered oxides have attracted many attentions for their superior specific capacity and low cost, but they are subjected to fast structural degradation during cycling. Herein, the Al and Sm co‐doped LiNi0.83Co0.07Mn0.10O2 (SC‐NCM‐AS) single‐crystal is demonstrated to overcome their cycling instability issue, and its mechanistic origin for improved structural stability is investigated. It is found that soluble Al ions are homogenously incorporated in the LiNi0.83Co0.07Mn0.10O2 (SC‐NCM) lattice, while Sm ions tends to aggregate in the SC‐NCM outer surface layer. The Li/Ni cation disordering is greatly suppressed through the pillaring effect of stronger AlO bond in SC‐NCM single crystals. Sm‐concentrated outer surface layer can effectively prevent the dissolution of transition metals from SC‐NCM‐AS and inhibit undesirable side reactions induced by the organic electrolyte. This synergistic effect facilitates to suppress the formation of LiOH/Li2CO3 and oxygen vacancies, resulting in released the internal strain, decreased in‐plane transition metals migration and gliding, and eventually preventing formation of nanocracks in SC‐NCM‐AS single crystals upon cycling at high cut‐off voltage. Consequently, Al and Sm co‐doped SC‐NCM exhibits a high specific capacity of 222.4 mAh g−1 and remarkable cycling performance with a capacity retention of 91.1% for 100 cycles. [ABSTRACT FROM AUTHOR]

Cobalt‐free cathode materials have garnered increased attention for applications in next‐generation batteries for electric vehicles, as cobalt is considered to have at a high supply chain risk. Here, the use of a localized saturated electrolyte (LSE) to enable stable cycling of a cobalt‐free, low‐nickel layered‐oxide cathode LiNi0.7Mn0.25Al0.05O2 (NMA‐70) to higher voltages (4.6 V) in a lithium‐metal battery is demonstrated. Compared to the baseline LP57 electrolyte, the LSE extends the cycle life from ≈100 cycles to ≈400 cycles before reaching 80% capacity retention. Visual indicators of cell degradation, such as product deposition, are observed on electrodes cycled in LP57. It is shown that cycling NMA‐70 in LSE reduces the overall active material loss and overpotential growth during extended cycling. This is attributed to the formation of a beneficial fluorinated interphase layer, a lower degree of rock‐salt phase formation, and a reduction in the gas evolution from the cathode surface. The decrease in gas evolution from the cathode cycled in LSE reflects a lower degree of electrolyte reactivity and an overall improvement in the safety characteristics of the cell. This study highlights the importance of a stable electrolyte to enable the high‐voltage cycling of alternative, lower nickel, and cobalt‐free cathodes. [ABSTRACT FROM AUTHOR]

Redox reactions of oxygen have been considered critical in controlling the electrochemical properties of lithium-excessive layered-oxide electrodes. However, conventional electrode materials without overlithiation remain the most practical. Typically, cationic redox reactions are believed to dominate the electrochemical processes in conventional electrodes. Herein, we show unambiguous evidence of reversible anionic redox reactions in LiNi1/3 Co1/3 Mn1/3 O2 . The typical involvement of oxygen through hybridization with transition metals is discussed, as well as the intrinsic oxygen redox process at high potentials, which is 75 % reversible during initial cycling and 63 % retained after 10 cycles. Our results clarify the reaction mechanism at high potentials in conventional layered electrodes involving both cationic and anionic reactions and indicate the potential of utilizing reversible oxygen redox reactions in conventional layered oxides for high-capacity lithium-ion batteries.

Redox reactions of oxygen have been considered critical in controlling the electrochemical properties of lithium-excessive layered-oxide electrodes. However, conventional electrode materials without overlithiation remain the most practical. Typically, cationic redox reactions are believed to dominate the electrochemical processes in conventional electrodes. Herein, we show unambiguous evidence of reversible anionic redox reactions in LiNi1/3 Co1/3 Mn1/3 O2 . The typical involvement of oxygen through hybridization with transition metals is discussed, as well as the intrinsic oxygen redox process at high potentials, which is 75 % reversible during initial cycling and 63 % retained after 10 cycles. Our results clarify the reaction mechanism at high potentials in conventional layered electrodes involving both cationic and anionic reactions and indicate the potential of utilizing reversible oxygen redox reactions in conventional layered oxides for high-capacity lithium-ion batteries.

The fast capacity degradation of silicon‐based anodes significantly limits the application in lithium‐ion battery (LIB) industries. Recently, Si−CuO composites have been reported as promising anodes in terms of being cost‐effective and technically feasible, but improved cycle stability is still desired. This work introduces a proper amount of NiO into the Si−CuO composites via a facile high‐energy ball‐milling method. The study reveals that compared to the binary Si‐CuO composites, Si−CuO−NiO samples have less pronounced volume change during the cycles due to the formation of rich‐Si NiSi2. More specifically, Si87.5(CuO)3.4(NiO)9.1 shows the highest 100‐cycle capacity retention of ∼86.9 % at 0.2 C with an average coulombic efficiency of ∼99.4 %. Moreover, the thermal stability investigation demonstrates that the temperature of 600 °C is suitable to coat a carbon layer on Si87.5(CuO)3.4(NiO)9.1, where the microstructure and the uniform element distribution produced in the milling process as well as the suppression to the cr‐Li3.75Si formation can be maintained to the maximum extent, thus with further enhanced electrochemical performance. [ABSTRACT FROM AUTHOR]

Silicon‐based anodes composed of micrometric Si, graphite (MAG), LiI−Li3PS4 solid electrolyte (LPSI), and carbon nanofiber (CNF), which can be prepared by straightforward manual grinding, are proposed in this study. The relation between composition and performance of the anodes is investigated through the mixture design approach, which allows discrimination of the effect of each component and also the combined effect of the components on the end performance. By increasing the fraction of LPSI in the anode, the capacity of the electrode is improved, and the best performance is obtained when the Si/MAG/LPSI ratio is 15 : 15 : 70. This composite integrated with 5 wt % CNF exhibits a capacity above 1200 mAh g−1 throughout 50 cycles in a bulk‐type all‐solid‐state battery with LPSI as the electrolyte. Scanning electron microscopy (SEM) confirms that the presence of LPSI suppresses the aggregation of Si and improves the ratio of Si available for lithiation/delithiation. [ABSTRACT FROM AUTHOR]

All‐solid‐state batteries with solid ionic conductors packed between solid electrode films can release the dead space between them, enabling a greater number of cells to stack, generating higher voltage to the pack. This Review is focused on using high‐voltage cathode materials, in which the redox peak of the components is extended beyond 4.7 V. Li−Ni−Mn−O systems are currently under investigation for use as the cathode in high‐voltage cells. Solid electrolytes compatible with the cathode, including halide‐ and sulfide‐based electrolytes, are also reviewed. Discussion extends to the compatibility between electrodes and electrolytes at such extended potentials. Moreover, control over the thickness of the anode is essential to reduce solid‐electrolyte interphase formation and growth of dendrites. The Review discusses routes toward optimization of the cell components to minimize electrode‐electrolyte impedance and facilitate ion transportation during the battery cycle. [ABSTRACT FROM AUTHOR]

Having a high theoretical capacity density of 4200 mAh g−1, silicon has been highlighted as one of the most promising anode materials for lithium-ion batteries. Countless silicon-based materials have been proposed and reported in research articles, mostly synthesized using bottom-up methods. While the infamous volume expansion issue can be settled with the bottom-up processes, the complicated protocols and high cost leave a non-neglectable gap between laboratory-scale and mass production. The top-down ball-milling method is still favored by industrial suppliers because of its simplicity and cost-effectiveness, even with compromised electrochemical performances. This paper reviews the latest development of ball-milling-based silicon anode materials. Although the ball-milling process seems straightforward, the procedures and parameters influencing the product have hardly been discussed in research papers compared to the bottom-up ones. This paper reviews recent advances in ball-milling-based silicon anode materials, provides a material comparison, and discusses how ball milling can provide lithium-ion batteries with greater possibilities at a larger scale. [ABSTRACT FROM AUTHOR]

This article is a brief introduction to lithium-ion batteries. People may be curious about lithium-ion batteries because they have the same in their mobile phones, laptops, etc. Definitely, the 2019 Nobel Prize in Chemistry makes them more inquisitive. Therefore, this article depicts the basic concept of lithium-ion batteries, their diverse applications, and commercial prospects. Lithium-ion electrochemistry, including working principle, battery materials, challenges in real-life operations and their mitigation pathways, are vividly discussed herein. [ABSTRACT FROM AUTHOR]

The mixing of [V10O28]6− decavanadate anions with a dicationic gemini surfactant (gem) leads to the spontaneous self‐assembly of surfactant‐templated nanostructured arrays of decavanadate clusters. Calcination of the material under air yields highly crystalline, sponge‐like V2O5 (gem‐V2O5). In contrast, calcination of the amorphous tetrabutylammonium decavanadate allows isolation of a more agglomerated V2O5 consisting of very small crystallites (TBA‐V2O5). Electrochemical analysis of the materials' performance as lithium‐ion intercalation electrodes highlights the role of morphology in cathode performance. The large crystallites and long‐range microstructure of the gem‐V2O5 cathode deliver higher initial capacity and superior capacity retention than TBA‐V2O5. The smaller crystallite size and higher surface area of TBA‐V2O5 allow faster lithium insertion and superior rate performance to gem‐V2O5. [ABSTRACT FROM AUTHOR]

We classify the dynamic patterns that emerge in charging or discharging of Li‐ion batteries, under galvanostatic conditions, using simulations of the two‐phase one‐dimensional (1D) porous electrode model. This work examines the effect of the exchange current function, R0(X), which expresses the nature of kinetics. This extends our previous study with R0 = 1 where the same pattern emerges in charging or discharging, whether as a homogeneous or a step‐wise process made of multiple symmetry breaking events. With commonly‐used asymmetric R0(X), the emerging patterns may be one of the two above or as fronts that follow single SB event and the lithiation/delithiation behaviors are different. These effects are clear when parameters are uniform; nonuniformity leads to noise that mask the behavior. The full four‐variable model exhibits SB, even in absence of noise, since the liquid potential gradient (ϕl) works like a perturbation. This similarity allows us to derive approximations to the full model behavior. [ABSTRACT FROM AUTHOR]

As the research on lithium‐ion battery cathode materials gradually breaks through the saturation, the anode materials for lithium‐ion batteries have received wide attention because of their promising future. Silicon electrodes, in particular, are attracting increasing attention. In this paper, the Si/G precursor was achieved by simple mechanical ball milling. Two silicon based composite electrode materials Si@TA and Si@TA‐G were synthesized by spontaneous polymerization of tannic acid on precursor surface in Tris buffer solution. For the poor electrical conductivity of silicon, graphite was added as a carbon source to avoid the direct contact between silicon and electrolyte during charge/discharge process by forming tannic acid coating on silicon surface.The Si@TA composites achieve a discharge specific capacity of 927.4 mAh g−1 at 100 mA g−1 current density after 50 cycles with a retention rate of 87.1 % while the reversible capacity of Si@TA‐G is 1249.8 mAh g−1 with a retention rate is 93.6 %. This unique composite method provides new insights into the modification of silicon anode materials. [ABSTRACT FROM AUTHOR]

NASICON type NaSn2(PO4)3 (NSP) microspheres and nanorods were developed using a modified Pechini method and tested as anode materials for Lithium/Sodium storage applications. According to cyclic voltammetry investigation, NSP is associated with the conversion process between Sn and Sn (PO4)3 and the alloy reaction between Sn and NaxSn as an anode material for sodium-ion batteries, similar to lithium-ion batteries. The electrochemistry results revealed that NSPnr (nanorod) performs better in terms of capacity, cyclic stability, and rate capability than microspheres for sodium-ion batteries (for example, the specific capacity of NSPnr: 358 mAh g−1 and NSPms: 301 mAh g−1 at 200 mAg−1 over 200 cycles). The higher capacity of the NSPnr was derived from the large interlayer distance of nanorods, and the crystalline nature of the material resulted in increased kinetics of Na-ions and improved electrochemistry performances. However, in lithium-ion batteries, the NSP microsphere exhibits superior specific capacity and excellent cycling stability than NSP nanorods. This could be attributed to their spherical morphology, smaller crystallite size, and higher oxygen vacancy when processed by air. The excellent electrochemical performance of the NSPms electrode could be attributed to the well-dispersed spherical-shaped particle morphology, which allows fast Li+-ion migration during the electrochemical lithiation/delithiation process, particularly at high current density. The maximum capacity of 361 mAh g−1 and 227 mAh g−1 was observed when tested at high current densities of 2 A g−1 and 3 A g−1. [ABSTRACT FROM AUTHOR]