Li-ion Batteries Research Articles

Vertical-channel hierarchically porous 3D printed electrodes with ultrahigh mass loading and areal energy density for Li-ion batteries

Lithium-ion batteries (LIBs) are renowned for their high energy density, long lifespan, and minimal self-discharge, making them a prominent power supply system. However, the persistent demand for improved energy density coupled with mechanical stability remains a significant challenge, as efforts to enhance electrode thickness or achieve geometric complexity through conventional ink-casting methods have yielded limited results. To tackle this challenge, we applied a three-dimensional (3D) printing technique to swiftly construct 3D thick electrodes with ultrahigh mass loading. Combined with unidirectional ice-templating process, high mass loading electrodes with hierarchically porous structures were successfully fabricated. The mass loading of the 3D electrodes can reach up to 73.83 mg cm−2, significantly enhancing the areal capacity. The low tortuosity and good mechanical resilience of these structures enable fast ion and charge transport, leading to significant improvements in areal energy density without sacrificing the power density. The assembled full cell exhibits an impressive areal capacity of 10.34 mAh cm⁻2 at 0.2 C and an excellent energy density of 18.41 mWh cm−2, surpassing other 3D printed lithium-ion batteries. This approach marks a significant advancement in electrode structural design towards higher areal capacity and energy density, showcasing the intriguing potential of 3D printed batteries for practical applications. Additionally, it also highlights the scalability and design versatility provided by 3D printing technique.

Innovative approaches to optimizing Li-Ion battery cooling performance using gas mixtures

This study investigates the critical issue of thermal management in lithium-ion batteries, a vital concern for enhancing battery performance, safety, and longevity. While more complex cooling systems like liquid cooling, phase change materials, and two-phase systems offer superior thermal performance due to their higher heat transfer capabilities, they come with significant drawbacks. These include increased system complexity, higher costs, added weight, and the potential for leaks or other failures that can compromise safety and reliability. Consequently, simpler air-based cooling systems are often preferred in many applications, despite their inherently lower h coefficient. To bridge the performance gap between air and liquid cooling without resorting to complex engineering solutions, this study focuses on enhancing the h coefficient of air-based systems using innovative refrigerant gas mixtures. The use of refrigerant gas mixtures, specifically a blend of R1234ze(E), nitrogen, and neon, as an alternative to traditional cooling methods was explored. The study employed a comprehensive FEM model and experimental validation to evaluate free and forced convection in a slender, vertical cylindrical configuration. To analyze the impact on convective heat transfer, the key parameters CRate, T0 and Tamb were systematically varied. A dimensionless analysis then evaluated how thermodynamic properties influence h coefficient. This analysis led to the derivation of a dimensionless heat transfer function h(ρ, Cp, k, μ). The study aimed to significantly improve the efficiency of h by optimizing the gas mixture properties. The “Mixture Study” identifies the optimal refrigerant composition, where a specific mixture α of 86 % R1234ze(E), and 14 % neon demonstrated the best balance between heat transfer efficiency and enhanced thermal capacity. The heat transfer coefficient increases by around 65 % during natural convection and by around 80 % during forced convection. The percentage reduction of the thermal difference in temperature reaches approximately 10 % with a maximum of 4 K in natural convection conditions and a maximum of 36.5 % and a reduction of approximately 10 K compared to air cooling alone, effectively maintaining the battery within the optimal operating range of 293.15 K to 333.15 K. Notably, this composition increased the thermal power absorbed by the mixture by over 100 % under the same thermal difference. This research therefore provides valuable insights for developing more effective gas cooling strategies that ultimately enhance the performance, safety, and durability of batteries in various applications. By integrating the benefits of both cooling methods, the study paves the way for innovative thermal management solutions in battery technology.

The research of electrochemical performance of Mg-doped NaNi1/3Mn1/3Fe1/3O2 positive electrode materials

Abstract The demand for Li-ion batteries is increasing year by year, which poses a great challenge to the scarce Li and Co resources. Na-ion batteries are considered to be one of the potential energy storage batteries because of their low raw material cost, wide source of sodium resources, and prices that are not susceptible to market fluctuations. The layered oxide positive electrode (such as NaNi1/3Mn1/3Fe1/3O2, NMF) is a potential replacement due to its high-capacity characteristics and low-cost advantages. However, the rate performance of NMF is compromised by the slow migration kinetics of Na+ ions. Here, we used the Mg doping strategy to realize the enhancement of the rates and cycling properties of NMF. Our research shows that the 2% Mg-doped cathode material has superior rate performance and cycling performance. The discharge-specific capacities are 120.5 mAh/g at 0.1C and 88.9 mAh/g for 100 cycles at 0.5C with a high retention rate (85.2%).

Carboxylic Acid Assisted Synthesis of Crystalline Silicon Derived from Coal Fly-Ash for Li-Ion Batteries Anode Material

Carboxylic Acid Assisted Synthesis of Crystalline Silicon Derived from Coal Fly-Ash for Li-Ion Batteries Anode Material

Achieving Passive Thermal Runaway Propagation Resistance in Li-ion Battery Packs

Achieving Passive Thermal Runaway Propagation Resistance in Li-ion Battery Packs

Environmental and Energy Applications of Graphene-Based Nanocomposites: A Brief Review

Chemically stable two-dimensional nanostructured graphene with huge surface area, high electrical conductivity and mechanical excellence has gained significant research attention in the past two decades. Its excellent characteristics make graphene one of the important materials in various applications such as environmental and energy storage devices. Graphene no doubt has been a top priority among the carbon nanomaterials owing to its structure and properties. However, the functionalization of graphene leads to various nanocomposites where its properties are tailored to be suited for various applications with more performance, environmental friendliness, efficiency, durability and cost effectiveness. Graphene nanocomposites are said to exhibit more surface area, conductivity, power conversion efficiency and other characteristics in energy devices like supercapacitors. This review was aimed to present some of the applications of graphene-based nanocomposites in energy conversion devices like supercapacitors and Li-ion batteries and some of the environmental applications. It was observed that the performance of supercapacitors was obstructed due to restacking and agglomeration of graphene layers. This was addressed by combining MO (metal oxide) or CP (conducting polymer) with graphene as material for electrodes. Electrodes with CP or MO/graphene composites are summarized. Heterogeneous catalysts were of environmental concern in recent years. In this context, graphene-based nanocomposites gained significance due to expansion in structural diversity. A minimum overview is presented in this paper in terms of structural aspects and properties of GO/rGO-based materials used in supercapacitors and environmental applications like dye removal. Continuous efforts towards synthesis of productive graphene-based nanocomposites might lead to significant output in applications related to environment and energy sectors.

LSTM-Based SOC Estimation for Hybrid Energy Pack Combining Li-ion Battery and Supercapacitor

LSTM-Based SOC Estimation for Hybrid Energy Pack Combining Li-ion Battery and Supercapacitor

EV battery soH, soC monitor on the edge of speed control and fire protection

Lithium batteries are the most common energy storage devices in items such as electric vehicles, portable devices, and energy storage systems. However, if lithium batteries are not continuously monitored, their performance could degrade, their lifetime become shortened, or severe damage or explosion could be induced. To prevent such accidents, we propose a lithium battery state of health monitoring method and state of charge estimation algorithm based on the state of health results. And also speed control in electric vehicles is mandatory as it is used to influence the rotational speed of motors and machinery. This has a direct effect on the operation of the machine and is crucial for the quality and outcome of the work. Li-ion batteries have a lot of energy in them, and thermal runaway accelerates quicker the more power is in the battery itself. If a battery is fully charged and something happened inside it, then thermal runaway would happen really quickly. To overcome this, fire protection of electric vehicle is necessary.

Superior electrochemical performances of Lithium vanadium oxide with coconut shell-based porous carbon as the anode of the aqueous Li ion battery

Carbon materials, as the skeleton structure of electrode materials, are composited with lithium-ion anode materials, which not only increase the electrical conductivity of the materials, but also enhance the electrochemical performance of the electrode materials. In this paper, LiV3O8@C composites were prepared by using coconut shell-based porous carbon to structurally modulate aqueous lithium-ion anode materials. And three composites with different structures and sizes were successfully synthesized by hydrothermal method, hydrothermal stirring method and improved solid-phase method. After XRD and SEM analyses, it was found that all three composites maintained the monoclinic crystal system structure of LiV3O8, and the materials prepared by the hydrothermal method showed a smooth layer structure, while the materials prepared by the hydrothermal stirring method and the solid-phase method showed nanorods with different sizes. The prepared anode materials and LiFePO4 cathode materials were assembled into an aqueous lithium-ion full battery, and were subjected to charge/discharge tests, cyclic voltammetry and electrochemical impedance spectroscopy. The results indicate that the electrochemical performances of the three composites are significantly improved compared with the pure LiV3O8. Specifically, the discharge capacities of the two groups of nanorod-like composites were 112.2 mAh/g and 85.5 mAh/g at a rate of 0.2 C, which were improved by as much as two times compared with the pure LiV3O8. However, the composite material with layered structure not only reaches an initial discharge specific capacity of 148.39 mAh/g, which is 2.7 times higher than that of the pure LiV3O8, but also effectively slows down the dissolution effect of LiV3O8 by compositing with the carbon material, and at the same time, it shows excellent rate performance.

Numerical and experimental investigations on thermal performance of Li-ion battery during explosion

Electric vehicles (EVs) are eco-friendly alternative to internal combustion (IC) engine based vehicles to combat with global warming. Lithium-ion batteries (LIBs) are adopted in EVs and their performance and longevity depends on thermal environment. Inadequate thermal management results in suboptimal performance, thermal runaway and consequent explosion in extreme cases. The present study delves into the experimental investigation on catastrophic failure of a Lithium ion cell under abusive conditions. The temperature variations leading up to the point of explosion were meticulously monitored, revealing a critical temperature of 440 K just before the explosion. The pressure waves during the explosion gives the sound pressure levels from 46.2 dB to 83.85 dB within a 34 ms time window and the predominant portion of sound generated during the explosion lies in the range of 129 to 3488 Hz. The battery pack discharge experiments show a temperature rises above the critical limit of 313.15 K and sudden voltage drops to the cut of value of 20 V at t = 850 s during 1C discharge condition, which shows the warning of explosion. Numerical model was developed to simulate the complex conjugate heat transfer in the cell and simulation results are validated. To underscore the practical implications, a case study of fire accident during battery cooling experiment was presented. From the insights gained by explosion of single-cell and fire accident of battery, several recommendations are provided, which includes the orientation of cells within the EVs aiming at the safety of battery design and operation.

Analysis of hybrid solutions with Li-ion battery system for DP-2 vessels

An economical approach for incorporating Battery Energy Storage Systems (BESS) onto DP-2 vessels is presented in this research. The paper deals with developing a Battery Optimization for Optimal Sizing and Throughput Energy Regulation (BOOSTER) framework for putting research findings into practice by optimizing battery size, technology choice and power generation scheduling while considering battery degradation. Twelve battery sizes are analyzed based on three key performance metrics: return on investment, payback period, and years of profitability. A Mixed Integer Linear Programming (MILP) is developed to operate the energy and power management system of the vessel in a fuel and economically efficient manner. The study considers two load profiles of a DP-2 vessel operating near Taiwan and the North Sea. Our findings emphasize the significance of taking battery ownership costs in the form of energy throughput cost and fuel price into account, resulting in a longer battery lifetime and higher return on investment. The research also proposes a BESS operation matrix that provides vessel operators with valuable information on BESS usage for economic benefits. This matrix translates analytics and decision-making into tangible actions that can be implemented in real-time operations. Based on the findings, energy systems may be optimized for a sustainable future, which benefits vessel operators and industry stakeholders.

Enhanced Li-ion battery performance based on multisite oxygen vacancies in WO3-x@rGO negative electrode

While transition-metal oxides have emerged as promising candidates for lithium energy storage, several issues are remained to be addressed such as low conductivity, rate performance, and recyclability. In this study, a three-dimensional interconnected sheet-like heterostructure of WO3-x coated with reduced graphene oxide (rGO) was synthesized using the hydrothermal method. This structure significantly enhanced the conductivity of WO3-x. By combining the heterojunction with oxygen vacancies (OV), the active sites are enlarged, promoting the effective movement of ions and electrons at the interface between the WO3-x and rGO. The prepared anode exhibits a high specific capacity of 1202.6 mAh/g at 0.1 A g−1, with a cycling retention rate of 96 % after 100 cycles. Meanwhile, even at 5 A g−1, it still maintains a capacity of 305 mAh/g after 500 cycles. Theoretical calculations reveal that the presence of the composite heterogeneous structure enables WO3-x@rGO to possess appropriate adsorption energy, lower work function, and reduced barriers. This arrangement provides abundant active sites, promoting the rapid penetration of the electrolyte and enhancing the interface reaction kinetics, which is consistent with the experimental results. This study offers a new strategy for Li-ion anode materials.

Defect-driven ion storage on hexagonal boron nitride for fire-safe and high-performance lithium-ion batteries

The mass market adoption of electric vehicles has increased the risk of safety concerns, such as overheating and flammability. Rational design of fire-safe and high-capacity anodes with thermal tolerance, capable of fast-charging and long cycle-life, is crucial for the development of next generation Li-ion batteries operating under extreme conditions. Here we report a defect engineered hexagonal boron nitride (hBN) anode to mediate the safety dilemma. We demonstrate that the defects generated via cryomilling catalyze the reversible LiF formation and enable the pseudocapacitive type Li-ion storage on hBN. The non-flammability and excellent thermal tolerance of hBN allows high specific capacity (880 mAh/g @ 25 mA/g), rate performance (480 mAh/g @ 5 A/g) and stable cycling (5000 cycles) at 60 °C. The Li-ion full-cell with the defective hBN anode and the conventional cathode (LiNiMnCoO2) delivers significantly higher energy (400 Wh kg−1) and power density (1 kW kg−1) when compared to graphite/LiNiMnCoO2 full-cells (121 Wh kg−1 and 250 W kg−1). First-principles calculations confirm that nitrogen antisite (NBVN) defects are responsible for the electrochemical activation of otherwise inactive hBN. The strategy of defect-induced electrochemical activation opens up new avenues in the design of high-performance electrode materials for numerous secondary batteries.

Theoretical approaches to study degradation in Li-ion battery cathodes: Crucial role of exchange and correlation

Abstract Li-ion batteries have become essential in energy storage, with demand rising steadily. Cathodes, crucial for determining capacity and voltage, face challenges like degradation in the form of thermal runaway and battery failure. Understanding these degradation phenomena is vital for developing mitigation strategies. Experimental techniques such as XAS, XPS, PES, UV–Vis, RIXS, NMR, and OEMS are commonly used, but theoretical modelling, particularly atomistic modelling with density-functional theory (DFT), provides key insights into the microscopic electronic behaviours causing degradation. While DFT offers a precise formulation, its approximations in the exchange-correlation functional and its ground-state, 0K limitations necessitate additional methods like ab initio molecular dynamics. Recently, many-body electronic structure methods have been used alongside DFT to better explain electron–electron interactions and temperature effects. This review emphasizes material-specific methods and the importance of electron–electron interactions, highlighting the role of many-body methods in addressing key issues in cathode degradation and future development in electron–phonon coupling methods. Graphical abstract

A design guideline of graphite/silicon composite electrode for extremely fast charging Li ion batteries

Achieving extremely fast charging (XFC) capabilities is critical for the development of lithium-ion batteries (LIBs) for electric vehicles (EVs). However, conventional LIBs with graphite anodes face challenges with lithiation at high charging rates, often resulting in Li plating. Incorporating silicon (Si) with graphite to form graphite/Si composite electrodes presents a potential solution, but the detailed design rules for these composite electrodes are not yet well understood. Here, we systematically investigate the impact of varying Si content on the fast-charging behaviors of graphite/Si composite electrodes. Through electrochemical analysis, in-situ X-ray diffraction (XRD), and a newly developed reaction dynamics analysis cell, our research demonstrates that the lithiation reaction proceeds inhomogeneously and becomes increasingly concentrated on the Si component as the charging rate increases. Based on these findings, a physics-based model further explores the effects of Si properties and electrode design on XFC ability, proposing guidelines for designing advanced graphite/Si composite electrodes to achieve robust XFC abilities in LIBs.

Dual-active sites and reversible-structural covalent organic framework for highly stable alkali metal-ion batteries

Organic materials are promising candidates for energy storage due to their sustainability, environmental friendliness, and structural designability. However, their application is severely limited due to short lifespan and sluggish kinetics caused by low redox stability, solubility, and low electronic conductivity. Here, we designed a polyimide-conjugated covalent organic framework (NAA-COF). Its highly covalent framework cannot only endow the organic material with strong π–π interactions and robust network ensuring its structure stability, but also offer open channels for rapid ions/electrons transfer inside. Additionally, the introduction of multiple redox-active sites can significantly enhance ion-storage capacity. Consequently, when evaluated as a cathode for Li-ion batteries, NAA-COF exhibits large capacity of 220mAh/g, superb initial coulombic efficiency (90 %), good voltage platform, long lifespan (10000 cycles), and high-rate performance (110 mAh/g at 10 A/g). More importantly, even for Na-/K-ion batteries, the exceptional electrochemical performances can still be maintained. In situ transmission electron microscopy (TEM) and in/ex situ spectroscopy further elucidate the low volume expansion (12.2 %) during the lithiation process and 8-electron reaction mechanism for the NAA-COF cathode. This work provides a high-performance universal COF cathode material that can simultaneously satisfy the requirements of alkali metal-ion batteries.

Investigation of hydrohalic acids as lixiviants for the leaching of cathode metals from spent lithium-ion batteries

The exploration of alternative energy sources is inextricably linked with energy storage considerations. Current high density energy storage options on the market rely heavily on lithium (Li)-based technologies. A projected increase in energy storage technology demand has sounded the alarm on a need to develop suitable approaches for the recovery of the various constituent metals from spent Li-ion batteries (LIBs). This, coupled with urgent consideration for the environment has necessitated the investigation of various LIB metal recovery techniques. In this work, we explore the novel application of the hydrohalic acids, hydrobromic (HBr) and hydroiodic (HI) acid, as lixiviants in a series of leaching experimental investigations on LIB cathode powder. A methodology for battery disassembly and cell cathode material recovery is presented leading up to the metal leaching. Our results indicate that the lixiviants can be utilized in the absence of a reducing agent which is typically present in conventional LIB leaching systems. The highest recoveries of the constituent metals, Co, Li, Mn and Ni in the HI system were 92.9 %, 93.6 %, 93.1 % and 94.5 % respectively, at an operating temperature of 60 ℃ and with a 1.5 M HI concentration. The HBr system achieved metal recoveries of 90.6 %, 89.1 %, 83.1 % and 96.4 % for Co, Li, Mn and Ni respectively, at 60 ℃ and using 2 M HBr. Kinetic studies showed that the leaching mechanism for both acids follow a chemical reaction-controlled model.

Climate-adaptive battery solutions for renewable microgrids: A case study in Indian coastal and inland regions

The utilization of renewable energy has the potential to alleviate global warming, reduce carbon emissions in the environment, and offer sustainable energy solutions to remote regions. Presently, 13 % of the worldwide population resides in isolated inland and coastal areas where electricity remains inaccessible. Consequently, implementing microgrids powered by renewable energy sources becomes essential to enhance electricity accessibility in these remote locations. This study aims to identify efficient and cost-effective renewable energy technologies suitable for deployment inland and coastal areas. The techno-economic feasibility of renewable energy systems is being evaluated in two distinct locations: Yadavole (inland) and Uppada (coastal) villages in the Indian state of Andhra Pradesh. The energy analysis encompasses various sources, including photovoltaic, diesel generators, wind turbines, flywheels, and batteries (Li-ion and lead-acid). The HOMER software conducts all necessary modeling and simulations for economic analysis and optimal system sizing. According to the simulation results, the most viable microgrid configurations for the inland region, Yadavole, are photovoltaic/diesel and generator/Li-ion. In contrast, for the coastal region, Uppada, photovoltaic/diesel, and generator/lead-acid configurations prove to be the most promising configurations. Moreover, a MATLAB model of the proposed system is created to analyze energy quality. Given the superior performance of Li-ion batteries in elevated temperatures typically found inland, this study recommends a diversified range of battery solutions. Specifically, Li-ion batteries are recommended for inland areas, while lead-acid batteries are recommended for coastal regions. This approach aims to efficiently store renewable power by the specific climatic conditions of each area. It is crucial to systematically analyze region-specific renewable energy technologies to provide valuable insight to stakeholders involved in investment and energy policy decisions.

Cargo E-Bike Robust Speed Control Using an MPC Battery Thermal Lumped Model Approach

Cargo e-bikes are expected to convey heavy loads in all aspects of daily life. Also, these vehicles are expected to maintain a consistent speed to meet mobility needs while optimizing the battery design. In this paper, a control model is developed to improve rotational speed motor control via the battery model predictive controller (MPC) thermal model designed based on experimental field test data. Experimental field tests are performed to provide the relation between battery surface and ambient temperatures in different road types and weight conditions. For this purpose, in different slope ranges, the pedal load/activity and voltage-current data are logged to use as experimental input in an MPC-integrated 1D model. To obtain the desired thermal conditions in the Li-Ion battery, the MPC battery thermal model is defined based on the thermal lumped model approach. In the next step, the generated MPC model is used as a function for longitudinal speed control in the MPC motor torque control model subjected to uncertain road disturbances. Then, the outputs of the control models are compared using the MPC parameters oc weight factors and prediction horizon. Thus, the speed control model for cargo e-bikes is presented with increased robustness using the MPC battery thermal lumped model approach considering energy and Li-Ion battery life-cycle efficiency methods regardless of driving performance needs.

Accelerated aging protocols design for Li-ion batteries based on equivalence of the degradation mechanisms

A reasonable and efficient accelerated aging protocol is crucial for the design and application of Li-ion batteries. Most of the current research on accelerated aging protocols simply apply higher level of stress to raise the acceleration rate, without considering the aging mechanism. However, the same capacity attenuation doesn't mean the same state of health, considering the nonequivalence of mechanism. For the first time, this study proposes a method to design the accelerated aging protocols completely equivalent to the normal aging state and have a high acceleration ratio. Firstly, two degradation mechanisms, loss of lithium inventory (LLI) and active materials of positive electrode (LAM_PE), are decoupled quantitatively for the normal aging process. The LLI accelerated protocol: The protocol involves two parts: first is charging at low-temperature. Charging with low rate under low temperature can generate large amount of plated lithium metal, second is resting at high-temperature(60 °C) after charging, which leads to transformation of the deposited lithium into SEI film faster because of Arrhenius formula. The resting temperature is not designed to be too high to avoid thermal runaway of battery.Secondly, different cycle protocols are designed to specifically accelerate single mechanism. The equivalence of these mechanisms is experimentally verified through CP-SEM, SEM-EDS, HRTEM and XPS. Finally, combined accelerated protocols are designed by combining and matching single accelerated protocols based on the proportions of degradation mechanisms during normal aging. Under these protocols, cells experience the same aging pathway as the normal aging ones. The proposed aging protocols could accelerate the battery aging experiment by 62 times and 39 times under the extreme and gentle conditions respectively.