Fast Charging Of Lithium-ion Batteries Research Articles

Introducing Ionic Transport Islands in Graphite Anode towards Fast-Charging Lithium-Ion Batteries

Abstract The development of lithium-ion batteries (LIBs) possessing excellent fast charging performance is particularly important for expanding the worldwide application market of LIBs. However, the grievous growth of lithium dendrites during high rate charging and discharging process occurring on the surface of the anode material still restricts the development of commercial fast charging LIBs, which raises capacity deterioration and even enormous safety risks. Herein, we developed simple physical mixing of active carbon (AC) powder into graphite negative slurry to generate the hybrid fast charging anode (called AS anode), which can realize unprecedented fast charging capability whether at room temperature or low temperature, along with greatly improved capacity retention cycling at high 2C rate. Importantly, the density functional theory calculation and combined characterizations including in-situ electrochemical confocal system spectroscopy and lithium ion (Li+) diffusion coefficient analysis can decipher that AC particles with rapid Li+ diffusion and adsorption can act as ion transport islands in graphite electrode to accelerate the transport process of lithium ion inside the whole negative electrode, leading to the faster charging performance. This work not only promotes the development of anode construction with fast charging capability for LIBs, but also deciphers the ion transport mechanism inside the electrode.

SiO with ZSM-5 to regulate interfacial stability for fast-charging lithium-ion batteries

Silicon monoxide (SiO) anodes hold great promise for the high-energy advanced battery systems. However, their rate and cycling behavior confront rapid capacity degradation due to the sluggish charge transfer kinetic and serious volume expansion. Though different tactics mitigate this degradation, the effective strategy is still needed to further improve the charge diffusion and mass shift. Here, it is suggested that the stable and fast ion transfer channels are established and dominated by the ZSM-5, combining with PEO, which depresses the volume expansion and leads to the enhanced tolerance during cycling for the SiO anodes. The different molar ratio of ZSM-5/PEO solid state electrolyte impacts greatly the battery performance. This study conducts the interface issues and proposes the integration of ZSM-5 molecular sieve to improve the contact between the solid electrolyte PEO and electrode active material SiO. This resulted in the enhanced ion conductivity and superior hardness in comparison to the pure SiO anodes, correspondingly, an increase in the diffusion coefficient and the electronic conductivity of the fabricated SiO electrode is realized. The optimized anodes, achieves 5.0 A/g rate property with 300 cycles stable cycling and a capacity retention ratio of 82%. This study offers valuable insights into the rational design of cost-effective and high specific energy SiO-based solid-state lithium-ion batteries.

An Implementation of Quasi-Newton Algorithm for Fast-charging Lithium-Ion Battery (LIB) Optimization in Electric Vehicle Application

Lithium-Ion Battery (LIB) is still an effective alternative technology in maximizing the efficiency of electric vehicles (EV). The application of EVs has had a significant impact in order to reduce the issue of global problems - reducing carbon gas emissions. The LIB charging mechanism with the fast-charging method is an alternative to the application of EVs on a more massive scale. However, the dynamics of the battery where the battery work function can decrease over time will affect battery performance. In addition, fast-charging efforts at LIB with maximum speed have the impact of increasing the risk of battery temperature and the existence of a larger gap in battery degradation. This paper proposes the application of Limited-Memory-Broyden-Fletcher-Goldfarb-ShannoBound Constrained (L-BFGS-B) algorithm for Lithium-Ion Battery (LIB) fast-charging optimization as an innovative solution approach in dealing with the complex LIB fastcharging dynamics. The results show that this approach is able to improve fast-charging speed and efficiency.

Investigation on heat generation in fast charging of lithium-ion batteries: Effect of charging rate and battery component thickness

Understanding heat generation mechanisms during fast charging is essential for designing and optimizing lithium-ion batteries. In this study, we have formulated a three-dimensional electrochemical-thermal coupling model for pouch lithium-ion batteries. The model is validated by the experimental results based on the distribution of temperature, current, and voltage. We investigate the effects of charging rate, active material coating thickness, and current collector thickness (each at three levels) on heat generation and temperature distribution. The electrodes account for most of the total heat generation (87.5% with a 2.5C charging rate), and the percentage decreases as the charging rate increases. The heat generated at the negative electrode is slightly higher than that at the positive electrode. Reversible heat is the main heat source at a low charging rate, and it decreases as the charging rate rises. The effects of battery component thicknesses on thermal behaviors under fast charging are significant. The overall battery temperature increases by 11.5 K as the positive electrode thickness increases from 40 to 70 µm due to the rise in ohmic resistance and polarization resistance within the electrode. The increased ohmic resistance in the separator and the current collector raises the temperature. Reducing the thickness of the current collector by 33% resulted in a doubling of heat generation from the current collectors. Yet, it had minimal impact on the overall temperature of the battery.

Porous current collector for fast-charging lithium-ion batteries

Porous current collector for fast-charging lithium-ion batteries

Reconstructable Carbon Monolayer-MoS2 Intercalated Heterostructure Enabled by Atomic Layers-Confined Topotactic Transformation for Ultrafast Lithium Storage.

The intercalation structure of two-dimensional materials with expanded interlayer distance can facilitate mass transport, which is promising in fast-charging lithium-ion batteries (LIBs). However, the designed intercalation structures will be pulverized and destroyed under tough working conditions, causing overall performance deterioration of the batteries. Here, we present that an intercalated heterostructure made of the typical layered material of MoS2 intercalated by N-doped graphene-like carbon monolayer (MoS2/g-CM) through a polymer intercalation strategy exhibits a unique behavior of reversible reconstructability as an LIB anode during cycling. A mechanism of "carbon monolayers-confined topotactic transformation" is proposed, which is evidenced by substantial in/ex situ characterizations. The intercalated heterostructure of MoS2/g-CM featuring a reconstructable property and efficient interlayer electron/ion transport exhibits an unprecedented rate capability up to 50 A g-1 and outstanding long cyclability. Moreover, the proposed strategy based on g-CM intercalation has been extended to the MoSe2 system, also realizing reconstructability of the intercalated heterostructure and improved LIB performance, demonstrating its versatility and great potential in applications.

One-step pore diffusion mechanism of Li+ in solid electrolyte interphase for fast-charging lithium-ion battery

One-step pore diffusion mechanism of Li+ in solid electrolyte interphase for fast-charging lithium-ion battery

Electrochemical-Thermal-Mechanical Coupling Analysis of Lithium-Ion Batteries under Fast Charging

Thermal runaway and volume expansion caused by temperature rise under fast charging of lithium-ion batteries (LIBs) are the major reasons of battery explosion and cycle performance degradation. In this work, considering the radiation heat transfer on the battery surface, an electrochemical-thermal-mechanical coupling model of cylindrical LIBs under fast charging (state of charge (SOC) ≤80%) is developed in order to investigate the distributions of the temperature and stress. Then, choosing 18650 LIBs as the object, the charge efficiency, temperature, and stress distributions are compared between fast charging and galvanostatic operation under SOC≤80%, respectively. Finally, the influences of the thickness, particle radius, the maximum lithium-ion concentration of the cathode, and initial electrolyte concentration on the temperature, radial stress, and hoop stress of LIB during charge are explored, respectively. Numerical results show that fast charging improves 20.8% of the charge efficiency. Increasing the cathodic thickness and decreasing the cathodic maximum lithium-ion concentration or initial electrolyte concentration can reduce the temperature of LIB during the charge. The results of this work will provide some reference value for the design of LIBs under fast charging.

FeNb11O29 and related niobate anodes for fast-charging lithium-ion batteries: a review

AbstractThe main request to be fulfilled for the wide distribution of electric vehicles is the availability of fast-charging lithium-ion batteries (LIBs). However, fast charging accelerates the degradation of a battery, particularly at ambient temperature, and the main responsible one is the anode compartment. The research is indeed devoted to developing new anode materials for LIBs with outstanding performances at high rates. FeNb11O29 (FNO), a double shear phase, also known as a Wadsley–Roth phase, with an intrinsic pseudocapacitance, was recently proposed as anode in LIBs, thanks to its high theoretical capacity (400 mAh g−1), high operating voltage (~ 1.6 V vs Li+/Li) and an amazing structural stability. In this review, after the discussion of strengths and weaknesses of FNO, the structural features of both its polymorphic forms, with a particular focus on the niobium and iron neighbourhoods, will be described. Then, the working mechanism and the structure-electrochemistry relationships will be treated, with an in-depth analysis of the pseudo-capacitive behaviour, i.e., the key to understand its electrochemical performances. The strategies to mitigate its main drawbacks, i.e., the poor electronic conductivity and the limited lithium diffusion, will be also dealt with. In the final paragraph, the electrochemical performances of some other analogues niobates will be briefly described.

Ultrasonic Non-Destructive Testing on Fast-Charging Lithium-Ion Battery’s Capacity Fading

Fast charging technology provides a solution to the issue of charging time for power supplies with long life requirements. However, it will shorten the charging period while also hastening the power battery’s capacity degradation, reducing its service life. The ultrasonic inspection technique has been widely used for the internal structure detection and reaction process characterisation of lithium-ion batteries because of its nondestructive testing properties. This paper presents a method for monitoring the capacity attenuation of a fast-charging battery by calculating the ultrasonic attenuation coefficient α. The experimental findings indicate that the battery’s capacity is more vulnerable to lithium plating during high-rate charging. The parameter α can be employed to illustrate the energy dissipation characteristics of sound as it propagates through the electrode. Moreover, the inhomogeneous ageing of battery electrode material is observed and quantified based on the differences in acoustic signals, which provides new insights into battery health management and uneven ageing assessment.

Interfacial carbon tailoring of porous SiOx/carbon nanotube hybrids towards high-rate lithium storage

Fast charging Lithium-ion batteries (LIBs) is highly required with the massive development of the electric vehicle market. Integrating silicon with carbon nanotubes (CNTs) has shown great promise for constructing high-rate anodes of LIBs. However, current reported silicon axially coated CNTs electrodes fail to provide a robust conductive connection within the interfacial layer, causing unsatisfactory rate performance. In this paper, a series of novel coaxial hollow nanocables of SiOx/C coated CNTs composite were presented based on a simple sol–gel method and subsequent calcination. Due to the uniform composition of carbon and SiOx at sub-nanometer scale in the coating layer, a strong 3D conductive network is formed between the internal carbon nanotubes and the neighboring electrode particles. When utilized as LIBs anodes, such novel hybrids manifest high reversible capacity (511 mA h g−1 remained after 500 cycles at 0.5 A g−1), high-rate capability (232 mA h g−1 at 5 A g−1) and ultra-long high-current cycling stability (396 mA h g−1 remained after 1000 cycles at 1.0 A g−1). The structural characterization and electrochemical dynamics analysis show that the synergistic effect of abundant mesoporous channels in the coating layer and strong carbon 3D conductive network makes this unique composite structure exhibit excellent electrochemical performance. This work sheds novel light on the wisely design of advanced Si-based anodes with enhanced fast charging performance.

Balancing the Ion/Electron Transport of Graphite Anodes by a La-Doped TiNb2O7 Functional Coating for Fast-Charging Li-Ion Batteries.

A functional coating layer (FCL) is widely applied in fast-charging lithium-ion batteries to improve the sluggish Li+ transport kinetics of traditional graphite anodes. However, blindly increasing the Li+ conductivity for FCL reduces the overall electron conductivity of the anodes. Herein, we decoupled the effect of La-doping on TiNb2O7 (TNO) in terms of the phase evolution, Li+/electron transport, and lithiation behavior, and then proposed a promising La0.1TNO FCL with balanced Li+/electron transport for a fast-charging graphite anode. By optimizing the doping concentration of La, more holes are introduced into the TNO as electron carriers without causing lattice distortion, thus maintaining the fast Li+ diffusion channel in TNO. As a result, the graphite with La0.1TNO FCL delivers an excellent capacity of 220.2 mAh g-1 (96.3% retention) after 450 cycles at 3 C, nearly twice that of the unmodified one.

High Voltage Electrolyte Design Mediated by Advanced Solvation Chemistry Toward High Energy Density and Fast Charging Lithium‐Ion Batteries

AbstractElectrolyte is critical for transporting lithium‐ion (Li+) in lithium‐ion batteries (LIBs). However, there is no universally applicable principle for designing an optimal electrolyte. In most cases, the design process relies on empirical experiences and is often treated as highly confidential proprietary information. Herein, a solvation structure‐related model for the quantitative design of electrolytes is introduced, focusing on the principles of coordination chemistry. As a paradigmatic example, a high‐voltage electrolyte (i.e., 4.5 V vs anode) aimed at achieving a high energy density and fast charging LIB, which is specifically composed of an emerging, well‐constructed hybrid hard carbon‐silicon/carbon‐based anode, and lithium cobalt oxide cathode, is developed. Not only the functions of each electrolyte component at the molecular scale within the Li+ solvation structure are analyzed but also an interfacial model is introduced to elucidate their relationship with the battery performance. This study represents a pioneering effort in developing a methodology to guide electrolyte design, in which the mutual effects of the Li+ de‐solvation process and solid electrolyte interface (SEI) on the electrode surface are explored concurrently to understand the root cause of superior performance. This innovative approach establishes a new paradigm in electrolyte design, providing valuable insights at the molecular level.

Amorphous Anode Materials for Fast-charging Lithium-ion Batteries.

Fast-charging technology is set to revolutionize the field of lithium-ion batteries (LIBs), driving the creation of next-generation devices with the ability to get charged within a short span of time. From the anode perspective, it is of paramount importance to design materials that can withstand continuous Li+ insertion/deinsertion at high charging rates and still remain unaffected by factors such as mechanical fractures, electrolyte side reactions, polarisation, lithium plating and heat generation. Herein, the recent advancements in the design of amorphous materials as anodes for fast-charging LIBs have been discussed. While the development of this particular class of materials for application in high-rate anodes has been paid limited attention in recent literature, it holds immense promise for improving the fast-charging capabilities. This concept summarizes the recent strides made in this emerging field, outlining the strategies employed in the design of amorphous anodes and emphasizing the crucial role played by the amorphous nature in achieving fast-charging performance. Further, the successive initiatives that can be undertaken to drive the progress of amorphous materials for fast charging LIBs have also been detailed, which could potentially improve their commercial viability.

Surface Decoration of TiC Nanocrystals onto the Graphite Anode Enables Fast-Charging Lithium-Ion Batteries.

To significantly reduce the charging time of commercial lithium-ion batteries (LIBs), it is essential to control the surface properties of graphite anodes because the charging process involves sluggish interfacial kinetics between graphite and the electrolyte. For the effective surface modification of graphite, herein we demonstrate the surface decoration with titanium carbide (TiC) nanocrystals onto graphite particles via a simple wet-coating process. The high electrical conductivity, low Li+ adsorption energy, and small surface diffusion barrier of the TiC nanocrystals facilitate fast Li+ adsorption and migration in the graphite surface by reducing the overpotential upon the charging process. The feasibility of the TiC nanocrystal-decorated graphite (TiC@AG) anode is thoroughly examined with an in-depth understanding of the interfacial reaction mechanism. Furthermore, the full-cell with a commercial cathode (LiNi0.8Co0.1Mn0.1O2) and TiC@AG anode demonstrates an impressive capacity retention (94.5%) after 300 cycles under fast-charging condition (3 C-charging and 1 C-discharging) without any sign of Li plating. The charging time of the TiC@AG full-cell was estimated at 16.2 min (80% of state of charge), which is substantially shorter than that of the artificial graphite full-cell. Our findings offer practical insights into the design principles of advanced graphite anodes, contributing to the realization of fast-charging LIBs.

High-Rate SiO Lithium-Ion Battery Anode Enabled by Rationally Interfacial Hybrid Encapsulation Engineering.

The development of a high-rate SiO lithium-ion battery anode is seriously limited by its low intrinsic conductivity, sluggish interfacial charge transfer (ICT), and unstable dynamic interface. To tackle the above issues, interfacial encapsulation engineering for effectively regulating the interfacial reaction and thus realizing a stable solid electrolyte interphase is significantly important. Hybrid coating, which aims to enhance the coupled e-/Li+ transport via the employment of dual layers, has emerged as a promising strategy. Herein, we construct a hybrid MXene-graphene oxide (GO) coating layer on the SiO microparticles. In the design, Ti3C2Tx MXene acts as a "bridge", which forms a close covalent connection with SiO and GO through Ti-O-Si and Ti-O-C bonds, respectively, thus greatly reducing the ICT resistance. Moreover, the Ti3C2Tx with rich surface groups (e.g., -OH, -F) and GO outer layers with an intertwined porous framework synergistically enable the pseudocapacitance dominated behavior, which is beneficial for fast lithium-ion storage. Accordingly, the as-made Si@MXene@GO anode exhibits considerably reinforced lithium-ion storage performance in terms of superior rate performance (1175.9 mA h g-1 at 5 A g-1) and long cycling stability (1087.6 mA h g-1 capacity retained after 1000 cycles at 2.0 A g-1). In-depth interfacial chemical composition analysis further reveals that an inorganically rich interphase with a gradient distribution of LiF and Li2O formed at the electrolyte/anode interface ensures mechanical stability during repeated cycles. This work paves a feasible way for maximizing the potential of SiO anodes toward fast-charging lithium-ion batteries.

Fluorine-Terminated Self-Assembled Monolayers Grafted Graphite Anode Inducing a LiF-Dominated SEI Inorganic Layer for Fast-Charging Lithium-Ion Batteries.

The electrochemical kinetic processes of Li+ ions, including the desolvation of the Li+ ions from the electrolyte to the solid electrolyte interphase (SEI), the transportation of desolvated Li+ ions across the SEI, and the charge transfer at the interface between the SEI and graphite, determine the rate performance and cycling stability of the graphitic anode in lithium-ion batteries (LIBs). In this work, fluorine-terminated self-assembled monolayers were grafted on the surface of spherical graphite particles to regulate the chemical composition and structure of SEI formed on the graphite surface in the presence of conventional ester electrolytes. The comprehensive characterization and first-principles calculation results illustrate that a uniform LiF-dominated SEI film can be generated on the as-functionalized graphite anode due to the carbon-fluorine bonds' cleavage of fluorine-terminated self-assembled monolayers. The LiF-dominated SEI film is particularly beneficial for desolvated lithium-ion transport across the SEI, affording LiCoO2//graphite full cells with substantially enhanced fast-charging capability and cycle stability. This strategy should be potentially useful for modifying other anode materials to regulate the interfacial chemistry between the anode and electrolyte in lithium-ion batteries.

Fast-charging graphite anode for lithium-ion batteries: Fundamentals, strategies, and outlooks

The basic requirements for lithium-ion batteries in the field of electric vehicles are fast charging and high energy density. This will enhance the competitiveness of electric vehicles in the market while reducing greenhouse gas emissions and effectively preventing environmental pollution. However, the current lithium-ion batteries using graphite anodes cannot achieve the goal of fast charging without compromising electrochemical performance and safety issue. This article analyzes the mechanism of graphite materials for fast-charging lithium-ion batteries from the aspects of battery structure, charge transfer, and mass transport, aiming to fundamentally understand the failure mechanisms of batteries during fast charging. In addition, we review and discuss recent advances in strategies for optimizing fast-charging performance and summarize current improvement methods in graphite electrodes, electrolytes, battery structures, and charging algorithms. Moreover, the challenges and promising concepts for developing future fast-charging graphite anode are emphasized. This review is of great significance for better designing and optimizing graphite materials for high-safety and fast-charging lithium-ion batteries.

3D Pathways Enabling Highly-Efficient Lithium Reservoir for Fast-Charging Batteries.

Enhancing the mobility of lithium-ions (Li+) through surface engineering is one of major challenges facing fast-charging lithium-ion batteries (LIBs). In case of demanding charging conditions, the use of a conventional artificial graphite (AG) anode leads to an increase in operating temperature and the formation of lithium dendrites on the anode surface. In this study, a biphasic zeolitic imidazolate framework (ZIF)-AG anode, designed strategically and coated with a mesoporous material, is verified to improve the pathways of Li+ and electrons under a high charging current density. In particular, the graphite surface is treated with a coating of a ZIF-8-derived carbon nanoparticles, which addresses sufficient surface porosity, enabling this material to serve as an electrolyte reservoir and facilitate Li+ intercalation. Moreover, the augmentation in specific surface area proves advantageous in reducing the overpotential for interfacial charge transfer reactions. In practical terms, employing a full-cell with the biphasic ZIF-AG anode results in a shorter charging time and improved cycling performance, demonstrating no evidence of Li plating during 300 cycles under 3.0C-charging and 1.0C-discharging. The research endeavors to contribute to the progress of anode materials by enhancing their charging capability, aligning with the increasing requirements of the electric vehicle applications.

In-Operando Detection Method for Lithium Metal Deposition during Fast Charging of Lithium-Ion Batteries Derived from Impedance Modeling

Lithium-ion batteries play a key role in the electrification of the transport sector. However, to replace combustion engines with battery-powered electric drive trains, the fast charging capability is essential. Therefore, it is necessary to identify the optimum operating window for lithium-ion cells. A strict criterion for optimization is to prevent lithium metal deposition at the anode, as this undesired side reaction can pose serious safety risks. An efficient technique to optimize charging strategies while tracking lithium plating is needed, as existing approaches have limitations such as a lack of in-line capability, low time precision, or complex experimental setups. In this study, a simple lithium metal deposition detection method is derived from a three-electrode setup. This in-operando method is applied during fast charging using dynamic electrochemical impedance spectroscopy. To model the acquired impedance spectra, a novel equivalent circuit is developed. The model is used to elucidate characteristic impedance features of anodes with deposited lithium metal. These observed characteristic features are then applied to a simplified measurement method in full cells using a single-frequency signal. The precision and high temporal resolution of both methods are demonstrated through validation. Furthermore, the simplified method can be applied in in-operando applications, making it suitable for diverse research and industrial contexts.