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Building a multifunctional Li/Na-B-Mg-Si-O-F-rich hybrid ion/electron interface network on 4.65 V LCO enables reversible Co/O redox, excellent interface stability, and fast-charging Cyclability. [Display omitted] High-voltage and fast-charging LiCoO 2 (LCO) is key to high-energy/power-density Li-ion batteries. However, unstable surface structure and unfavorable electronic/ionic conductivity severely hinder its high-voltage fast-charging cyclability. Here, we construct a Li/Na-B-Mg-Si-O-F-rich mixed ion/electron interface network on the 4.65 V LCO electrode to enhance its rate capability and long-term cycling stability. Specifically, the resulting artificial hybrid conductive network enhances the reversible conversion of Co3+/4+/O2−/n− redox by the interfacial ion–electron cooperation and suppresses interface side reactions, inducing an ultrathin yet compact cathode electrolyte interphase. Simultaneously, the derived near-surface Na+/Mg2+/Si4+-pillared local intercalation structure greatly promotes the Li+ diffusion around the 4.55 V phase transition and stabilizes the cathode interface. Finally, excellent 3 C (1 C = 274 mA g−1) fast charging performance is demonstrated with 73.8% capacity retention over 1000 cycles. Our findings shed new insights to the fundamental mechanism of interfacial ion/electron synergy in stabilizing and enhancing fast-charging cathode materials. [ABSTRACT FROM AUTHOR]

Anionic and cationic redox chemistries boost ultrahigh specific capacities of Li‐rich Mn‐based oxides cathodes (LRMO). However, irreversible oxygen evolution and sluggish kinetics result in continuous capacity decay and poor rate performance, restricting the commercial fast‐charging cathodes application for lithium ion batteries. Herein, the local electronic structure of LRMO is appropriately modulated to alleviate oxygen release, enhance anionic redox reversibility, and facilitate Li+ diffusion via facile surface defect engineering. Concretely, oxygen vacancies integrated on the surface of LRMO reduce the density of states of O 2p band and trigger much delocalized electrons to distribute around the transition metal, resulting in less oxygen release, enhancing reversible anionic redox and the MnO6 octahedral distortion. Besides, partially reduced Mn and lattice vacancies synchronously stimulate the electrochemical activity and boost the electronic conductivity, Li+ diffusion rate, and fast charge transfer. Therefore, the modified LRMO exhibits enhanced cyclic stability and fast‐charging capability: a high discharging capacity of 212.6 mAh·g−1 with 86.98% capacity retention after 100 cycles at 1 C is obtained and to charge to its 80%, SOC is shortened to 9.4 min at 5 C charging rate. This work will draw attention to boosting the fast‐charging capability of LRMO via the local electronic structure modulation. [ABSTRACT FROM AUTHOR]

Highlights: The microstructure of graphite upon rapid Li+ intercalation is a mixture of differently staging structures in the macroscopic and microscopic scales due to the incomplete and inhomogeneous intercalation reactions hindered by the sluggish reaction kinetics. The Li+ interface diffusion dominates the reaction kinetics at high rates in thin graphite electrode, while Li+ diffusion through the electrode cannot to be neglected for thick graphite electrode. Fast-charging lithium-ion batteries are highly required, especially in reducing the mileage anxiety of the widespread electric vehicles. One of the biggest bottlenecks lies in the sluggish kinetics of the Li+ intercalation into the graphite anode; slow intercalation will lead to lithium metal plating, severe side reactions, and safety concerns. The premise to solve these problems is to fully understand the reaction pathways and rate-determining steps of graphite during fast Li+ intercalation. Herein, we compare the Li+ diffusion through the graphite particle, interface, and electrode, uncover the structure of the lithiated graphite at high current densities, and correlate them with the reaction kinetics and electrochemical performances. It is found that the rate-determining steps are highly dependent on the particle size, interphase property, and electrode configuration. Insufficient Li+ diffusion leads to high polarization, incomplete intercalation, and the coexistence of several staging structures. Interfacial Li+ diffusion and electrode transportation are the main rate-determining steps if the particle size is less than 10 μm. The former is highly dependent on the electrolyte chemistry and can be enhanced by constructing a fluorinated interphase. Our findings enrich the understanding of the graphite structural evolution during rapid Li+ intercalation, decipher the bottleneck for the sluggish reaction kinetics, and provide strategic guidelines to boost the fast-charging performance of graphite anode. [ABSTRACT FROM AUTHOR]

Despite numerous research on new active materials for anodes, graphite remains the most commonly used material in Li-ion batteries. The spherical shape of the graphite particles has proven to be beneficial for application in electric vehicles, especially for fast charging. So far, the spheroidization of natural flake graphite is conducted by a rigid and inefficient cascade process. In this work, a scalable classifier system was used for spheroidization, and it was demonstrated that a spheroidization time of 15 min is sufficient to improve material properties and enhance electrochemical performance while maintaining high process yields of 55%. Insights into the influence of the morphology on the intrinsic and structural properties of the graphite particles and manufactured electrodes are provided. Spheroidization creates a more efficient pore network in the coating layer while reducing the internal resistance and increasing the surface area of the particles by a factor of 1.8. We demonstrate that the spherical shape improves the discharge rate capability by 1.8, and the specific charge capacity could be enhanced by more than 237% at a C-rate of 3. An additional carbon coating could significantly decrease the specific surface area and increase the specific capacity at high C-rates. [ABSTRACT FROM AUTHOR]

The difficulties to identify the rate‐limiting step cause the lithium (Li) plating hard to be completely avoided on graphite anodes during fast charging. Therefore, Li plating regulation and morphology control are proposed to address this issue. Specifically, a Li plating‐reversible graphite anode is achieved via a localized high‐concentration electrolyte (LHCE) to successfully regulate the Li plating with high reversibility over high‐rate cycling. The evolution of solid electrolyte interphase (SEI) before and after Li plating is deeply investigated to explore the interaction between the lithiation behavior and electrochemical interface polarization. Under the fact that Li plating contributes 40 % of total lithiation capacity, the stable LiF‐rich SEI renders the anode a higher average Coulombic efficiency (99.9 %) throughout 240 cycles and a 99.95 % reversibility of Li plating. Consequently, a self‐made 1.2‐Ah LiNi0.5Mn0.3Co0.2O2 | graphite pouch cell delivers a competitive retention of 84.4 % even at 7.2 A (6 C) after 150 cycles. This work creates an ingenious bridge between the graphite anode and Li plating, for realizing the high‐performance fast‐charging batteries. [ABSTRACT FROM AUTHOR]

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

The development of fast‐charging technologies is crucial for expediting the progress and promotion of electric vehicles. In addition to innovative material exploration, reduction in the tortuosity of electrodes is a favored strategy to enhance the fast‐charging capability of lithium‐ion batteries by optimizing the ion‐transfer kinetics. To realize the industrialization of low‐tortuosity electrodes, a facile, cost‐effective, highly controlled, and high‐output continuous additive manufacturing roll‐to‐roll screen printing technology is proposed to render customized vertical channels within electrodes. Extremely precise vertical channels are fabricated by applying the as‐developed inks, using LiNi0.6Mn0.2Co0.2O2 as the cathode material. Additionally, the relationship between the electrochemical properties and architecture of the channels, including the pattern, channel diameter, and edge distance between channels, is revealed. The optimized screen‐printed electrode exhibited a seven‐fold higher charge capacity (72 mAh g−1) at a current rate of 6 C and superior stability compared with that of the conventional bar‐coated electrode (10 mAh g−1, 6 C) at a mass loading of 10 mg cm−2. This roll‐to‐roll additive manufacturing can potentially be applied to various active materials printing to reduce electrode tortuosity and enable fast charging in battery manufacturing. [ABSTRACT FROM AUTHOR]

[Display omitted] High-energy-density lithium-ion batteries and sodium-ion batteries are two important rechargeable batteries in the large-scale electrochemical energy storage devices of modern society; however, the fast-charging of them, as one of the core technologies, is still not fully and adequately resolved, especially the correlated problems of the cathode side. This review highlights the key kinetically limiting factors in the process of fast-charging from the perspective of cathodic materials, and describes the various currently reported fast-charging cathode materials with improved rapid ions diffusion capability and fast reaction kinetics. Based on the energy-storage mechanism of cathode materials during fast-charging, a series of strategies, including nanostructure, doping and multiple-system, are discussed, while emphasis on the pseudocapacitive contribution in the battery type cathode materials for constructing the fast-charging lithium-ion batteries and sodium-ion batteries. [ABSTRACT FROM AUTHOR]

In recent years, the driving range of electric vehicles (EVs) has been dramatically improved. But the large‐scale adoption of EVs still is hindered by long charging time. The high‐energy LIBs are unable to be safely fast‐charged due to their electrode materials with unsatisfactory rate performance. Thus it is necessary to summarize the properties of cathode and anode materials of fast‐charging LIBs. In this review, we summarize the background, the fundamentals, electrode materials and future development of fast‐charging LIBs. First, we introduce the research background and the physicochemical basics for fast‐charging LIBs. Second, typical cathode materials of LIBs and the method to enhancing their fast‐charging properties are discussed. Third, the anode materials of LIBs and the strategies for improving their fast‐charging performance are analyzed. Finally, the future development of the cathode materials in fast‐charging LIBs is prospected. [ABSTRACT FROM AUTHOR]

Highlights: The Li+ diffusion coefficient of Co2VO4 is evaluated by theoretical calculation to be as high as 3.15 × 10–10 cm2 s−1, theoretically proving Co2VO4 a promising anode in fast-charging lithium-ion batteries. A hexagonal porous Co2VO4 nanodisk (PCVO ND) structure is designed, featuring a high specific surface area of 74.57 m2 g−1 and numerous pores with a pore size of 14 nm. The PCVO ND shows excellent fast-charging performance (a high average capacity of 344.3 mAh g−1 at 10 C for 1000 cycles with only 0.024% capacity loss per cycle for 1000 cycles). High-energy–density lithium-ion batteries (LIBs) that can be safely fast-charged are desirable for electric vehicles. However, sub-optimal lithiation potential and low capacity of commonly used LIBs anode cause safety issues and low energy density. Here we hypothesize that a cobalt vanadate oxide, Co2VO4, can be attractive anode material for fast-charging LIBs due to its high capacity (~ 1000 mAh g−1) and safe lithiation potential (~ 0.65 V vs. Li+/Li). The Li+ diffusion coefficient of Co2VO4 is evaluated by theoretical calculation to be as high as 3.15 × 10–10 cm2 s−1, proving Co2VO4 a promising anode in fast-charging LIBs. A hexagonal porous Co2VO4 nanodisk (PCVO ND) structure is designed accordingly, featuring a high specific surface area of 74.57 m2 g−1 and numerous pores with a pore size of 14 nm. This unique structure succeeds in enhancing Li+ and electron transfer, leading to superior fast-charging performance than current commercial anodes. As a result, the PCVO ND shows a high initial reversible capacity of 911.0 mAh g−1 at 0.4 C, excellent fast-charging capacity (344.3 mAh g−1 at 10 C for 1000 cycles), outstanding long-term cycling stability (only 0.024% capacity loss per cycle at 10 C for 1000 cycles), confirming the commercial feasibility of PCVO ND in fast-charging LIBs. [ABSTRACT FROM AUTHOR]

The diffusion of lithium ions and sodium ions in the anode materials is the main factor limiting the fast-charging performance of lithium and sodium-ion batteries. Due to the slow diffusion kinetics, taking lithium-ion batteries as an example, lithium ions and electrons accumulate locally in and on the surface of anode materials, especially in the process of fast-charging, resulting in uneven lithiation reaction and enormous transient stress, which leads to poor fast-charging performance. In this work, from the aspect of solving the ion diffusion rate, a capacitive type of energy storage is introduced by designing MoS 2 /rGO composite materials with pinned structures as fast-charging and stable anode materials for lithium-ion batteries and sodium-ion batteries. Combining the high ion conductivity and structural rigidity of the rGO conductive network with a few-layer MoS 2 provides a high ion diffusion rate and capacity. As expected, it can charge to 69 % in 25 min and 44 % in 3.2 min, respectively, providing a high capacity of 214.2 mAh g−1 at 10 A g−1 and a high-capacity retention of 85.31 % after 1, 000 cycles at the current density of 3 A g−1 in sodium-ion batteries. Similarly, the high reversible capacity of 910.5 mAh g−1 is achieved in the lithium-ion batteries, and there is almost no capacity loss after 1, 000 cycles at a high current density of 2 A g−1. This work may provide a reference for designing more fast-charging anode materials with high capacity. [Display omitted] • A stable structure in which MoS 2 with an interlayer spacing of 6.75 Å is uniformly dispersed on graphene. • By amino modification of MoS 2 stripped by lithium ion intercalation and the action of oxygen-containing functional groups of graphene. • MoS 2 /rGO composite materials can charge to 69 % in 25 min and 44 % in 3.2 min. • A high fast-charging capacity of 214 mAh g−1 at 10 A g−1 in SIBs, and 910 mAh g−1 in LIBs. [ABSTRACT FROM AUTHOR]

• Solvent-free electrode manufacturing process using polytetrafluoroethylene binder. • Dry-processed graphite anodes with high loading of active material. • Low tortuosity of dry-processed anode to enable better C-rate capability. • Excellent capacity retention during cycle life. • Preventing the lithium metal deposition during high C-rate charging. The electric vehicle (EV) market now requires advanced graphite anodes that can enable both high loading and quick charging. However, meeting these requirements simultaneously is challenging because of uneven electrochemical reactions and Li-plating on the surface of graphite anodes during fast-charging. In this study, high current density graphite anodes (≈6 mA cm−2) were fabricated through a solvent-free dry-electrode process using homogeneously dispersed polytetrafluoroethylene fibrils (2.0 wt% in electrode). This approach significantly improved the mechanical properties and electrochemical performance of graphite anodes during charge/discharge cycles. Dry-processed graphite anodes outperformed conventional wet-processed electrodes in terms of rate performance and capacity retention. Furthermore, LiNi 0.6 Co 0.2 Mn 0.2 O 2 (NCM)/graphite coin-type full cells are rapidly charged at a 3C-rate to induce Li-plating on the graphite surface. Thus, dry-processed graphite anodes exhibited less Li-plating than wet-processed anodes, implying that dry-processed electrodes are capable of fast-charging even under high-loading conditions. In addition, dry-processed graphite anodes retain 88.2 % capacity retention after 300 cycles, indicating a stable full-cell operation. Consequently, this research highlights the dry-electrode process as an innovative technique for electrode manufacturing, with the potential to reduce battery production costs while improving electrochemical performance during fast-charging. [ABSTRACT FROM AUTHOR]

Fast charging is one of the most important features to be accomplished for the improvement of electric vehicles. In the search for optimal use of active materials for this aim, we present a recipe to find the conditions for fast charging, fifteen minutes for 80 % of the State-of-Charge, of lithium-ion battery's single particle electrodes, thus taking advantage of the maximum possible capacity. A guide based on a general model that considers diffusion and charge transfer limitations under constant current is proposed. This guide was constructed on the basis of our previous theoretical development. A Python free and user-friendly package is provided to handle all experimental data processing and estimations. [ABSTRACT FROM AUTHOR]

In the past few decades, electrochemical energy storage systems, represented by alkali metal ion batteries and supercapacitors, have developed rapidly against the background of sustainable development. However, supercapacitors and alkali metal ion batteries, known for the high power density and high energy density, respectively, have struggled to meet the demand of high both power and energy densities energy storage devices. Therefore, integrating both energy storage mechanisms of supercapacitors and alkali metal ion batteries in the same system to attain device with comparatively high both power and energy densities has become the preferred approach for most researchers, and the representatives are assembling hybrid ion capacitors or introducing capacitive contribution into alkali metal ion batteries materials for fast-charging alkali metal ion batteries. For the former, many good quality publications have summarized and evaluated it, while the latter has not. In this review, we systematically summarize and insightfully discuss the phenomenon of introducing capacitive contribution into electrode materials of alkali metal ion batteries. Different methods of identifying capacitive and diffusive behaviors are reviewed, and the origin of the capacitive contribution in the battery materials combining the charge storage mechanism are explained, the influences of electrode materials' capacitive contribution on battery's energy and power densities are discussed in detail. Finally, we propose a design idea of electrode materials for battery with high both power and energy densities based on accurately understanding the rational capacitive contribution. [Display omitted] [ABSTRACT FROM AUTHOR]

Various automobile manufacturers have announced utilization of large-format cylindrical lithium-ion cells with innovative tab design for future vehicle generations. In this study, a cylindrical lithium-ion cell with novel full-tab design, state-of-the-art Ni-rich cathode and SiO x -C anode made specifically for automotive high-performance applications is used to parameterize a modeling framework and investigate the performance of large-format cylindrical cells. Much attention is paid to accurately modeling and validating the internal heat path of the enhanced tab design that is crucial for effective thermal management and is one of the biggest advantages compared to former single-tab cells. The spatially-resolved physico-chemical model is extensively validated within the temperature range of −20 °C to 65 °C with experimental data from multiple different test setups. The validated model is used to investigate optimal fast-charging times and thermal management strategies based on local anode voltage and plating risk under varying environmental condition. The findings are summarized in a generalized cooling-and-heating-map that provides an outlook on the fast-charging performance of less than 12 minutes from 10 % to 80 % state of charge for large-format cylindrical cells. • Flexible spatially-resolved modeling framework. • Extensive experimental validation with large-format full-tab cylindrical cells. • Calculation of fast-charging profiles based on local plating risk. • Investigation of optimal cooling and heating for best fast-charging times. • Towards a deep understanding of large-format cylindrical cells. [ABSTRACT FROM AUTHOR]

A resource reuse strategy for recycling discarded zinc fragments from zinc-ion battery manufacturing is proposed to obtain carbon-free ZnSe anode material for sodium-ion batteries (SIBs), which are currently regarded as the solutions for future large-scale energy storage devices and distributed generation. Carbon-free ZnSe with micro-structure is conveniently prepared by calcining the discarded zinc fragment and selenium powder. ZnSe at optimal condition has an impressive initial Coulombic efficiency of up to 95.8% and a high capacity of 387.0 mAh g−1 at 0.1 A g−1. Providing a capacity of 142.5 mAh g−1 at 30 A g−1 shows the superb rate capability. Attractively, only 17.1 s is taken to complete a single charge, proving its application potential in fast-charging SIBs. Meanwhile, it also exhibits a conspicuous cyclability, corresponding to a capacity of 386.6 mAh g−1 at 2 A g−1 over 1600 cycles. Additionally, the full cell assembled Na 3 V 2 (PO 4) 2 F 3 @reduced graphene oxide (rGO) cathode and ZnSe anode can light up 36 LEDs continuously with an ultimate energy density of 153.4 Wh Kg−1 and a maximum power density of 1108.5 W kg−1. This work aims to provide an available strategy for the synthesis of anode with high-rate performance and long cyclability for fast-charging SIBs. • Carbon-free ZnSe is derived from disused zinc foils as an anode for SIBs. • ZnSe exhibits excellent cycling stability and favorable rate performance. • The full battery can deliver an energy density of 153.4 Wh kg−1. [ABSTRACT FROM AUTHOR]

Electric vehicles (EVs) are being endorsed as the uppermost successor to fuel-powered cars, with timetables for banning the sale of petrol-fueled vehicles announced in many countries. However, the range and charging times of EVs are still considerable concerns. Fast charging could be a solution to consumers' range anxiety and the acceptance of EVs. Nevertheless, it is a complicated and systematized challenge to realize the fast charging of EVs because it includes the coordinated development of battery cells, including electrode materials, EV battery power systems, charging piles, electric grids, etc. This paper aims to serve as an analysis for the development of fast-charging technology, with a discussion of the current situation, constraints and development direction of EV fast-charging technologies from the macroscale and microscale perspectives of fast-charging challenges. If the problem of fast-charging can be solved, it will satisfy consumers' demand for 10-min charging and accelerate the development of electric vehicles. This paper summarized the development statuses, issues, and trends of the macro battery technology and micro battery technology. It is emphasized that to essentially solve the problem of fast charging, the development of new battery materials, especially anode materials with improved lithium ion diffusion coefficients, is the key. Finally, it is highlighted that red phosphorus is one of the most promising anodes that can simultaneously satisfy the double standards of high-energy density and fast-charging performance to a maximum degree. [ABSTRACT FROM AUTHOR]

Fast charging is an exciting topic in the field of electric and hybrid electric vehicles (EVs/HEVs). In order to achieve faster charging times, fast-charging applications involve high-current profiles which can lead to high cell temperature increase, and in some cases thermal runaways. There has been some research on the impact caused by fast-charging profiles. This research is mostly focused on the electrical, thermal and aging aspects of the cell individually, but these factors are never treated together. In this paper, the thermal progression of the lithium-ion battery under specific fast-charging profiles is investigated and modeled. The cell is a Lithium Nickel Manganese Cobalt Oxide/graphite-based cell (NMC) rated at 20 Ah, and thermal images during fast-charging have been taken at four degradation states: 100%, 90%, 85%, and 80% State-of-Health (SoH). A semi-empirical resistance aging model is developed using gathered data from extensive cycling and calendar aging tests, which is coupled to an electrothermal model. This novel combined model achieves good agreement with the measurements, with simulation results always within 2 °C of the measured values. This study presents a modeling methodology that is usable to predict the potential temperature distribution for lithium-ion batteries (LiBs) during fast-charging profiles at different aging states, which would be of benefit for Battery Management Systems (BMS) in future thermal strategies. [ABSTRACT FROM AUTHOR]