Lithium-ion batteries(LIBs)are an electrochemical energy storage technology that has been widely used for portable electrical devices,electric vehicles,and grid storage,etc.To satisfy the demand for user convenience e...Lithium-ion batteries(LIBs)are an electrochemical energy storage technology that has been widely used for portable electrical devices,electric vehicles,and grid storage,etc.To satisfy the demand for user convenience especially for electric vehicles,the development of a fast-charging technology for LIBs has become a critical focus.In commercial LIBs,the slow kinetics of Li+intercalation into the graphite anode from the electrolyte solution is known as the main restriction for fast-charging.We summarize the recent advances in obtaining fast-charging graphite-based anodes,mainly involving modifications of the electrolyte solution and graphite anode.Specifically,strategies for increasing the ionic conductivity and regulating the Li+solvation/desolvation state in the electrolyte solution,as well as optimizing the fabrication and the intrinsic activity of graphite-based anodes are discussed in detail.This review considers practical ways to obtain fast Li+intercalation kinetics into a graphite anode from the electrolyte as well as analysing progress in the commercialization of fast-charging LIBs.展开更多
In the context of rapid economic development,the pursuit of sustainable energy solutions has become a major challenge.Lithium-ion capacitors(LICs),which integrate the high energy density of lithium-ion batteries with ...In the context of rapid economic development,the pursuit of sustainable energy solutions has become a major challenge.Lithium-ion capacitors(LICs),which integrate the high energy density of lithium-ion batteries with the high power density of supercapacitors,have emerged as promising candidates.However,challenges such as poor capacity matching and limited energy density still hinder their practical application.Carbon nanofibers(CNFs),with their high specific surface area,excellent electrical conductivity,mechanical flexibility,and strong compatibility with active materials,are regarded as ideal electrode frameworks for LICs.This review summarizes key strategies to improve the electrochemical performance of CNF-based LICs,including structural engineering,heteroatom doping,and hybridization with transition metal oxides.The underlying mechanisms of each approach are discussed in detail,with a focus on their roles in improving capacitance,energy density,and cycling stability.This review aims to provide insights into material design and guide future research toward high-performance LICs for next-generation energy storage applications.展开更多
Energy storage is a key factor in the drive for carbon neutrality and carbon nanotubes(CNTs)may have an important role in this.Their intrinsic sp2 covalent structure gives them excellent electrical conductivity,mechan...Energy storage is a key factor in the drive for carbon neutrality and carbon nanotubes(CNTs)may have an important role in this.Their intrinsic sp2 covalent structure gives them excellent electrical conductivity,mechanical strength,and chemical stability,making them suitable for many uses in energy storage,such as lithium-ion batteries(LIBs).Currently,their use in LIBs mainly focuses on conductive networks,current collectors,and dry electrodes.The review outlines advances in the use of CNTs in the cathodes and anodes of LIBs,especially in the electrode fabrication and mechanical sensors,as well as providing insights into their future development.展开更多
Nowadays,new energy technologies are developing rapidly,energy storage systems are widely used,and lithium-ion batteries occupy a dominant position among them.Therefore,it is also very important to ensure their perfor...Nowadays,new energy technologies are developing rapidly,energy storage systems are widely used,and lithium-ion batteries occupy a dominant position among them.Therefore,it is also very important to ensure their performance,safety and service life through thermal management technology.In this paper,the causes of thermal runaway of lithium batteries are reviewed firstly,and three commonly used thermal management technologies,namely,air cooling,liquid cooling and phase change material cooling,are compared according to relevant literature in recent years.Air cooling technology has been widely studied because of its simple structure and low cost,but its temperature control effect is poor.Liquid cooling technology takes away heat through the circulation of liquid medium,which has a good cooling effect,but the system is relatively complex.Phase change material(PCM)cooling technology uses the high latent heat of PCM to absorb and re-lease heat,which can effectively reduce the peak temperature of a battery and improve the temperature uniformity,but the low thermal conductivity and liquid leakage are its main problems.To sum up,lithium-ion battery thermal management technology is moving towards a more efficient,safer and cost-effective direction.Coupled cooling systems,such as those combining liquid cooling and phase change material cooling,show great potential.Future research will continue to explore new materials and technologies to meet the growing demands of society and the market for lithium-ion battery perfor-mance and safety.展开更多
Metal-organic frameworks(MOFs)are import-ant as possible energy storage materials.Nitrogen-doped iron-cobalt MOFs were synthesized by a one-pot solvo-thermal method using CoCl_(3)·6H_(2)O and FeCl_(3)·6H_(2)...Metal-organic frameworks(MOFs)are import-ant as possible energy storage materials.Nitrogen-doped iron-cobalt MOFs were synthesized by a one-pot solvo-thermal method using CoCl_(3)·6H_(2)O and FeCl_(3)·6H_(2)O dis-solved in N,N-dimethylformamide,and were converted into Fe-Co embedded in N-doped porous carbon polyhedra by pyrolysis in a nitrogen atmosphere.During pyrolysis,the or-ganic ligands transformed into N-doped porous carbon which improved their structural stability and also their electrical contact with other materials.The Fe and Co are tightly bound together because of their encapsulation by the carbon nitride and are well dispersed in the carbon matrix,and improve the material’s conductivity and stability and provide additional capacity.When used as the anode for lithium-ion batteries,the material gives an initial capacity of up to 2230.7 mAh g^(-1)and a reversible capa-city of 1146.3 mAh g^(-1)is retained after 500 cycles at a current density of 0.5 A g^(-1),making it an excellent candidate for this purpose.展开更多
As a negative electrode material for lithium-ion batteries,silicon monoxide(SiO)suffers from dramatic volume changes during cycling,causing excessive stress within the electrode and resulting in electrode deformation ...As a negative electrode material for lithium-ion batteries,silicon monoxide(SiO)suffers from dramatic volume changes during cycling,causing excessive stress within the electrode and resulting in electrode deformation and fragmentation.This ultimately leads to a decrease in cell capacity.The trends of volume expansion and capacity change of the SiO/graphite(SiO/C)composite electrode during cycling were investigated via in situ expansion monitoring.First,a series of expansion test schemes were designed,and the linear relationship between negative electrode expansion and cell capacity degradation was quantitatively analyzed.Then,the effects of different initial pressures on the long-term cycling performance of the cell were evaluated.Finally,the mechanism of their effects was analyzed by scanning electron microscope.The results show that after 50 cycles,the cell capacity decreases from 2.556 mAh to 1.689 mAh,with a capacity retention ratio(CRR)of only 66.08%.A linear relationship between the capacity retention ratio and thickness expansion was found.Electrochemical measurements and scanning electron microscope images demonstrate that intense stress inhibits the lithiation of the negative electrode and that the electrode is more susceptible to irreversible damage during cycling.Overall,these results reveal the relationship between the cycling performance of SiO and the internal pressure of the electrode from a macroscopic point of view,which provides some reference for the application of SiO/C composite electrodes in lithium-ion batteries.展开更多
Electrospinning technology has emerged as a promising method for fabricating flexible lithium-ion batter-ies(FLIBs)due to its ability to create materials with desir-able properties for energy storage applications.FLIB...Electrospinning technology has emerged as a promising method for fabricating flexible lithium-ion batter-ies(FLIBs)due to its ability to create materials with desir-able properties for energy storage applications.FLIBs,which are foldable and have high energy densities,are be-coming increasingly important as power sources for wear-able devices,flexible electronics,and mobile energy applica-tions.Carbon materials,especially carbon nanofibers,are pivotal in improving the performance of FLIBs by increas-ing electrical conductivity,chemical stability,and surface area,as well as reducing costs.These materials also play a significant role in establishing conducting networks and im-proving structural integrity,which are essential for extend-ing the cycle life and enhancing the safety of the batteries.This review considers the role of electrospinning in the fabrication of critical FLIB components,with a particular emphasis on the integration of carbon materials.It explores strategies to optimize FLIB performance by fine-tuning the electrospinning para-meters,such as electric field strength,spinning rate,solution concentration,and carbonization process.Precise control over fiber properties is crucial for enhancing battery reliability and stability during folding and bending.It also highlights the latest research findings in carbon-based electrode materials,high-performance electrolytes,and separator structures,discussing the practical challenges and opportunities these materials present.It underscores the significant impact of carbon materials on the evolution of FLIBs and their potential to shape future energy storage technologies.展开更多
Rich-nickel layered ternary NCM811 has been widely used in the field of electric vehicles ascribed to its high theoretical specific capacity.However,poor cycling stability and rate-performance hindered its further dev...Rich-nickel layered ternary NCM811 has been widely used in the field of electric vehicles ascribed to its high theoretical specific capacity.However,poor cycling stability and rate-performance hindered its further development.Herein,different amounts of nitrogen-doped carbon were wrapped on the surface of NCM811 via a facile rheological phase method by regulating the amount of dopamine hydrochloride.The effects of the coating amounts on the structure and electrochemical performance are investigated.The DFT calculation,XRD,SEM and XPS reveal that an appropriate amount of nitrogen-doped carbon coating could uniformly form a protective layer on the NCM811 surface and the introduced N could anchor Ni atoms to inhibit the Li^(+)/Ni^(2+)mixing,but excessive amount would reduce Ni^(3+)to Ni^(2+)so as to conversely aggravate Li^(+)/Ni^(2+)mixing.Among the samples,the NCM811-CN0.75 sample exhibits the most excellent electrochemical performance,delivering a high-rate capacity of 151.6 mA·h/g at 10C,and long-term cyclability with 82.2%capacity retention after 300 cycles at 5C,exhibiting remarkable rate-performance and cyclability.展开更多
In view of the difference in coordination capacity of the glycine ion(Gly−),a selective leaching process for treating with spent lithium-ion batteries(LIBs)in the alkaline glycinate system was proposed.The effects of ...In view of the difference in coordination capacity of the glycine ion(Gly−),a selective leaching process for treating with spent lithium-ion batteries(LIBs)in the alkaline glycinate system was proposed.The effects of retention time,leaching temperature,concentration of glycine ligand,liquid-solid ratio(L/S),pH,stirring speed,and H_(2)O_(2) dosage on the leaching efficiency of valuable metals and the dissolution of impurities were investigated.When the spent LIBs were leached in 3 mol/L glycine aqueous solution with pH of 8,L/S of 5 mL:1 g and H_(2)O_(2) dosage of 5 vol.%at 90℃and stirring speed of 400 r/min for 3 h,lithium,cobalt,nickel,and manganese recoveries were 96.31%,83.18%,91.56%,and 31.16%,respectively,but Ca,Al,Fe,and Cu were almost insoluble.Meanwhile,the kinetic study showed that the activation energies for the leaching of Li,Co,Ni,and Mn were all in the range of 45−61 kJ/mol.The results indicate that the leaching process is all controlled by chemical reactions.展开更多
The degradation process of lithium-ion batteries is intricately linked to their entire lifecycle as power sources and energy storage devices,encompassing aspects such as performance delivery and cycling utilization.Co...The degradation process of lithium-ion batteries is intricately linked to their entire lifecycle as power sources and energy storage devices,encompassing aspects such as performance delivery and cycling utilization.Consequently,the accurate and expedient estimation or prediction of the aging state of lithium-ion batteries has garnered extensive attention.Nonetheless,prevailing research predominantly concentrates on either aging estimation or prediction,neglecting the dynamic fusion of both facets.This paper proposes a hybrid model for capacity aging estimation and prediction based on deep learning,wherein salient features highly pertinent to aging are extracted from charge and discharge relaxation processes.By amalgamating historical capacity decay data,the model dynamically furnishes estimations of the present capacity and forecasts of future capacity for lithium-ion batteries.Our approach is validated against a novel dataset involving charge and discharge cycles at varying rates.Specifically,under a charging condition of 0.25 C,a mean absolute percentage error(MAPE)of 0.29%is achieved.This outcome underscores the model's adeptness in harnessing relaxation processes commonly encountered in the real world and synergizing with historical capacity records within battery management systems(BMS),thereby affording estimations and prognostications of capacity decline with heightened precision.展开更多
Developing in situ spectroelectrochemistry methods,which can provide detailed information about species trans-formation during electrochemical reactions,is very important for studying electrode reaction mechanisms and...Developing in situ spectroelectrochemistry methods,which can provide detailed information about species trans-formation during electrochemical reactions,is very important for studying electrode reaction mechanisms and improving battery performance.Studying real-time changes in the surface of electrode materials during normal operation can be an effective way to assess and optimize the practical performance of electrode materials,thus,in situ and in operando characterization techniques are particularly important.However,batteries are hard to be studied by in situ characterization measurements due to their hermetically sealed shells,and there is still much room for battery characterizations.In this work,a specially designed battery based on the structure of coin cells,whose upper cover was transparent,was constructed.With such a device,acquisition of diffuse reflectance spectra of electrode materials during charging and discharging was realized.This not only provided a simple measurement accessory for diffuse reflectance spectroscopy(DRS),but also complemented in situ characterization techniques for batteries.Taking commonly used cathode materials in lithium-ion batteries(LIBs),including LiFePO_(4)(LFP),NCM811 and LiCoO_(2)(LCO)as examples,we managed tofind out the response relationships of different electrode materials to visible light of different wavelengths under ordinary reflectance illumination conditions.Heterogeneity of different cathode ma-terials on interaction relationships with the lights of different wavelengths was also revealed.This work demonstrated the capability of guiding wavelength selection for different materials and assessing electrochemical performances of in situ diffuse reflectance spectroelectrochemistry.By combining electrochemistry with diffuse reflectance spectroscopy,this work made an effective complementary for spectroelectrochemistry.展开更多
There is an urgent need for lithium-ion capacitors(LICs)that have both high energy and high power densities to meet the continuously growing energy storage demands.LICs effectively balance the high energy density of t...There is an urgent need for lithium-ion capacitors(LICs)that have both high energy and high power densities to meet the continuously growing energy storage demands.LICs effectively balance the high energy density of traditional rechargeable batteries with the superior power density and long life of supercapacitors(SCs).Nevertheless,the development of LICs is still hampered by limited kinetic processes and capacity mismatch between the cathode and anode.Metal-organic frameworks(MOFs)and their derivatives have received significant attention because of their extensive specific surface area,different pore structures and topologies,and customizable functional sites,making them compelling candidate materials for achieving high-performance LICs.MOF-derived carbons,known for their exceptional electronic conductivity and large surface area,provide improved charge storage and rapid ion transport.MOF-derived transition metal oxides contribute to high specific capacities and improved electrochemical stability.Additionally,MOF-derived metal compounds/carbons provide combined effects that increase both the capacitive and Faradaic reactions,leading to a superior overall performance.The review begins with an overview of the fundamental principles of LICs,followed by an exploration of synthesis strategies and ligand selection for MOF-based composite materials.It then analyzes the advantages of original MOFs and their derived materials,such as carbon materials and metal compounds,in enhancing LIC performance.Finally,the review discusses the major challenges faced by MOFs and their derivatives in LIC applications and offers future research directions and recommendations.展开更多
In the development of rechargeable lithium ion batteries(LIBs),silicon anodes have attracted much attention because of their extremely high theoretical capacity,relatively low Li-insertion voltage and the availability...In the development of rechargeable lithium ion batteries(LIBs),silicon anodes have attracted much attention because of their extremely high theoretical capacity,relatively low Li-insertion voltage and the availability of silicon resources.However,their large volume expansion and fragile solid electrolyte interface(SEI)film hinder their commercial application.To solve these problems,Si has been combined with various carbon materials to increase their structural stability and improve their interface properties.The use of different carbon materials,such as amorphous carbon and graphite,as three-dimensional(3D)protective anode coatings that help buffer mechanical strain and isolate the electrolyte is detailed,and novel methods for applying the coatings are outlined.However,carbon materials used as a protective layer still have some disadvantages,necessitating their modification.Recent developments have focused on modifying the protective carbon shells,and substitutes for the carbon have been suggested.展开更多
Silicon anodes are promising for use in lithium-ion batteries.However,their practical application is severely limited by their large volume expansion leading to irreversible material fracture and electrical disconnect...Silicon anodes are promising for use in lithium-ion batteries.However,their practical application is severely limited by their large volume expansion leading to irreversible material fracture and electrical disconnects.This study proposes a new top-down strategy for preparing microsize porous silicon and introduces polyacrylonitrile(PAN)for a nitrogen-doped carbon coating,which is designed to maintain the internal pore volume and lower the expansion of the anode during lithiation and delithiation.We then explore the effect of temperature on the evolution of the structure of PAN and the electrochemical behavior of the composite electrode.After treatment at 400℃,the PAN coating retains a high nitrogen content of 11.35 at%,confirming the presence of C—N and C—O bonds that improve the ionic-electronic transport properties.This treatment not only results in a more intact carbon layer structure,but also introduces carbon defects,and produces a material that has remarkable stable cycling even at high rates.When cycled at 4 A g^(-1),the anode had a specific capacity of 857.6 mAh g^(-1) even after 200 cycles,demonstrating great potential for high-capacity energy storage applications.展开更多
The aging characteristics of lithium-ion battery(LIB)under fast charging is investigated based on an electrochemical-thermal-mechanical(ETM)coupling model.Firstly,the ETM coupling model is established by COMSOL Multip...The aging characteristics of lithium-ion battery(LIB)under fast charging is investigated based on an electrochemical-thermal-mechanical(ETM)coupling model.Firstly,the ETM coupling model is established by COMSOL Multiphysics.Subsequently,a long cycle test was conducted to explore the aging characteristics of LIB.Specifically,the effects of charging(C)rate and cycle number on battery aging are analyzed in terms of nonuniform distribution of solid electrolyte interface(SEI),SEI formation,thermal stability and stress characteristics.The results indicate that the increases in C rate and cycling led to an increase in the degree of nonuniform distribution of SEI,and thus a consequent increase in the capacity loss due to the SEI formation.Meanwhile,the increases in C rate and cycle number also led to an increase in the heat generation and a decrease in the heat dissipation rate of the battery,respectively,which result in a decrease in the thermal stability of the electrode materials.In addition,the von Mises stress of the positive electrode material is higher than that of the negative electrode material as the cycling proceeds,with the positive electrode material exhibiting tensile deformation and the negative electrode material exhibiting compressive deformation.The available lithium ion concentration of the positive electrode is lower than that of the negative electrode,proving that the tensile-type fracture occurring in the positive material under long cycling dominated the capacity loss process.The aforementioned studies are helpful for researchers to further explore the aging behavior of LIB under fast charging and take corresponding preventive measures.展开更多
Recovering valuable metals from spent lithium-ion batteries(LIBs)for high value-added application is beneficial for global energy cycling and environmental protection.In this work,we obtain the high-performance N-dope...Recovering valuable metals from spent lithium-ion batteries(LIBs)for high value-added application is beneficial for global energy cycling and environmental protection.In this work,we obtain the high-performance N-doped Ni-Co-Mn(N-NCM)electrocatalyst from waste LIBs,for robust oxygen evolution application.Lithium-rich solution and NCM oxides are effectively separated from ternary cathode materials by sulfation roasting and low-temperature water leaching approach,in which the recovery efficiency of Li metal reaches nearly 100%.By facile NH_(3)treatment,the incorporation of N into NCM significantly increases the ratio of low-valence state Co^(2+)and Mn^(2+),and the formed Mn-N bond benefits the surface catalytic kinetics.Meanwhile,the N doping induces lattice expansion of the NCM,triggering tensile stress to favor the adsorption of the reactant.Thus,the optimized N-NCM electrocatalyst exhibits the superior overpotentials of 256 and 453 mV to achieve the current density of 10 and 100 mA/cm^(2),respectively,with a low Tafel slope of 37.3 mV/dec.This work provides a fresh avenue for recycling spent LIBs in the future to achieve sustainable development.展开更多
In this study,a roasting enhanced flotation process was proposed to recover LiMn_(2)O_(4) and grapite from waste lithium-ion batteries(LIBs).The effects of roasting temperature and time on the surface modification was...In this study,a roasting enhanced flotation process was proposed to recover LiMn_(2)O_(4) and grapite from waste lithium-ion batteries(LIBs).The effects of roasting temperature and time on the surface modification was investigated,and a series of analytical technologies were used to reveal process mechanism.The results indicate that LiMn_(2)O_(4) can be effectively separated from graphite via flotation after the roasting.The flotation grade of LiMn_(2)O_(4) was significantly increased from 63.10%to 91.36%after roasting at 550℃for 2 h.The TG-DTG analysis demonstrates that the difficulty in flotation separation of LiMn_(2)O_(4) from graphite is caused by the organic binder and electrolytes coating on their surfaces.The XRD,SEM,XPS,and contact angle analyses confirm that the organic films on the surfaces of those materials can be effectively removed by roasting,after which the wettability of LiMn_(2)O_(4) is regained and thus the surface wettability difference between the cathode and anode materials is increased significantly.The closed-circuit flotation test indicates that a LiMn_(2)O_(4) sample with high grade of 99.81%is obtained,while the recovery of LiMn_(2)O_(4) is as high as 99.40%.This study provides an economical and eco-friendly way to recycling waste LIBs.展开更多
Single cell temperature difference of lithium-ion battery(LIB) module will significantly affect the safety and cycle life of the battery. The reciprocating air-flow module created by a periodic reversal of the air flo...Single cell temperature difference of lithium-ion battery(LIB) module will significantly affect the safety and cycle life of the battery. The reciprocating air-flow module created by a periodic reversal of the air flow was investigated in an effort to mitigate the inherent temperature gradient problem of the conventional battery system with a unidirectional coolant flow with computational fluid dynamics(CFD). Orthogonal experiment and optimization design method based on computational fluid dynamics virtual experiments were developed. A set of optimized design factors for the cooling of reciprocating air flow of LIB thermal management was determined. The simulation experiments show that the reciprocating flow can achieve good heat dissipation, reduce the temperature difference, improve the temperature homogeneity and effectively lower the maximal temperature of the modular battery. The reciprocating flow improves the safety, long-term performance and life span of LIB.展开更多
Using low-cost FePO4·2H2O as iron source,Na2FePO4F/C composite is prepared by alcohol-assisted ball milling and solid-state reaction method.The XRD pattern of Na2FePO4F/C composite demonstrates sharp peaks,indica...Using low-cost FePO4·2H2O as iron source,Na2FePO4F/C composite is prepared by alcohol-assisted ball milling and solid-state reaction method.The XRD pattern of Na2FePO4F/C composite demonstrates sharp peaks,indicating high crystalline and phase purity.The SEM and TEM images reveal that diameter of the spherical-like Na2FePO4F/C particles ranges from 50 to 300 nm,and HRTEM image shows that the surface of Na2FePO4F/C composite is uniformly coated by carbon layer with a average thickness of about 3.6 nm.The carbon coating constrains the growth of the particles and effectively reduces the agglomeration of nanoparticles.Using lithium metal as anode,the composite delivers a discharge capacities of 102.8,96.4 and 90.3 mA·h/g at rates of 0.5C,1C and 2C,respectively.After 100 cycles at 0.5C,a discharge capacity of 98.9 mA·h/g is maintained with capacity retention of 96.2%.The Li+diffusion coefficient(D)of Na2FePO4F/C composite is calculated as 1.71×10^–9 cm^2/s.This study reveals that the simple solid state reaction could be a practical and effective synthetic route for the industrial production of Na2FePO4F/C material.展开更多
In order to characterize the voltage behavior of a lithium-ion battery for on-board electric vehicle battery management and control applications,a battery model with a moderate complexity was established.The battery o...In order to characterize the voltage behavior of a lithium-ion battery for on-board electric vehicle battery management and control applications,a battery model with a moderate complexity was established.The battery open circuit voltage (OCV) as a function of state of charge (SOC) was depicted by the Nernst equation.An equivalent circuit network was adopted to describe the polarization effect of the lithium-ion battery.A linear identifiable formulation of the battery model was derived by discretizing the frequent-domain description of the battery model.The recursive least square algorithm with forgetting was applied to implement the on-line parameter calibration.The validation results show that the on-line calibrated model can accurately predict the dynamic voltage behavior of the lithium-ion battery.The maximum and mean relative errors are 1.666% and 0.01%,respectively,in a hybrid pulse test,while 1.933% and 0.062%,respectively,in a transient power test.The on-line parameter calibration method thereby can ensure that the model possesses an acceptable robustness to varied battery loading profiles.展开更多
文摘Lithium-ion batteries(LIBs)are an electrochemical energy storage technology that has been widely used for portable electrical devices,electric vehicles,and grid storage,etc.To satisfy the demand for user convenience especially for electric vehicles,the development of a fast-charging technology for LIBs has become a critical focus.In commercial LIBs,the slow kinetics of Li+intercalation into the graphite anode from the electrolyte solution is known as the main restriction for fast-charging.We summarize the recent advances in obtaining fast-charging graphite-based anodes,mainly involving modifications of the electrolyte solution and graphite anode.Specifically,strategies for increasing the ionic conductivity and regulating the Li+solvation/desolvation state in the electrolyte solution,as well as optimizing the fabrication and the intrinsic activity of graphite-based anodes are discussed in detail.This review considers practical ways to obtain fast Li+intercalation kinetics into a graphite anode from the electrolyte as well as analysing progress in the commercialization of fast-charging LIBs.
文摘In the context of rapid economic development,the pursuit of sustainable energy solutions has become a major challenge.Lithium-ion capacitors(LICs),which integrate the high energy density of lithium-ion batteries with the high power density of supercapacitors,have emerged as promising candidates.However,challenges such as poor capacity matching and limited energy density still hinder their practical application.Carbon nanofibers(CNFs),with their high specific surface area,excellent electrical conductivity,mechanical flexibility,and strong compatibility with active materials,are regarded as ideal electrode frameworks for LICs.This review summarizes key strategies to improve the electrochemical performance of CNF-based LICs,including structural engineering,heteroatom doping,and hybridization with transition metal oxides.The underlying mechanisms of each approach are discussed in detail,with a focus on their roles in improving capacitance,energy density,and cycling stability.This review aims to provide insights into material design and guide future research toward high-performance LICs for next-generation energy storage applications.
文摘Energy storage is a key factor in the drive for carbon neutrality and carbon nanotubes(CNTs)may have an important role in this.Their intrinsic sp2 covalent structure gives them excellent electrical conductivity,mechanical strength,and chemical stability,making them suitable for many uses in energy storage,such as lithium-ion batteries(LIBs).Currently,their use in LIBs mainly focuses on conductive networks,current collectors,and dry electrodes.The review outlines advances in the use of CNTs in the cathodes and anodes of LIBs,especially in the electrode fabrication and mechanical sensors,as well as providing insights into their future development.
基金supported by the National Natural Science Foundation of China(No.52001045).
文摘Nowadays,new energy technologies are developing rapidly,energy storage systems are widely used,and lithium-ion batteries occupy a dominant position among them.Therefore,it is also very important to ensure their performance,safety and service life through thermal management technology.In this paper,the causes of thermal runaway of lithium batteries are reviewed firstly,and three commonly used thermal management technologies,namely,air cooling,liquid cooling and phase change material cooling,are compared according to relevant literature in recent years.Air cooling technology has been widely studied because of its simple structure and low cost,but its temperature control effect is poor.Liquid cooling technology takes away heat through the circulation of liquid medium,which has a good cooling effect,but the system is relatively complex.Phase change material(PCM)cooling technology uses the high latent heat of PCM to absorb and re-lease heat,which can effectively reduce the peak temperature of a battery and improve the temperature uniformity,but the low thermal conductivity and liquid leakage are its main problems.To sum up,lithium-ion battery thermal management technology is moving towards a more efficient,safer and cost-effective direction.Coupled cooling systems,such as those combining liquid cooling and phase change material cooling,show great potential.Future research will continue to explore new materials and technologies to meet the growing demands of society and the market for lithium-ion battery perfor-mance and safety.
文摘Metal-organic frameworks(MOFs)are import-ant as possible energy storage materials.Nitrogen-doped iron-cobalt MOFs were synthesized by a one-pot solvo-thermal method using CoCl_(3)·6H_(2)O and FeCl_(3)·6H_(2)O dis-solved in N,N-dimethylformamide,and were converted into Fe-Co embedded in N-doped porous carbon polyhedra by pyrolysis in a nitrogen atmosphere.During pyrolysis,the or-ganic ligands transformed into N-doped porous carbon which improved their structural stability and also their electrical contact with other materials.The Fe and Co are tightly bound together because of their encapsulation by the carbon nitride and are well dispersed in the carbon matrix,and improve the material’s conductivity and stability and provide additional capacity.When used as the anode for lithium-ion batteries,the material gives an initial capacity of up to 2230.7 mAh g^(-1)and a reversible capa-city of 1146.3 mAh g^(-1)is retained after 500 cycles at a current density of 0.5 A g^(-1),making it an excellent candidate for this purpose.
基金supported by the Fundamental Research Funds for the Central Universities(WK2090000055)Anhui Provincial Natural Science Foundation of China(2308085QG231).
文摘As a negative electrode material for lithium-ion batteries,silicon monoxide(SiO)suffers from dramatic volume changes during cycling,causing excessive stress within the electrode and resulting in electrode deformation and fragmentation.This ultimately leads to a decrease in cell capacity.The trends of volume expansion and capacity change of the SiO/graphite(SiO/C)composite electrode during cycling were investigated via in situ expansion monitoring.First,a series of expansion test schemes were designed,and the linear relationship between negative electrode expansion and cell capacity degradation was quantitatively analyzed.Then,the effects of different initial pressures on the long-term cycling performance of the cell were evaluated.Finally,the mechanism of their effects was analyzed by scanning electron microscope.The results show that after 50 cycles,the cell capacity decreases from 2.556 mAh to 1.689 mAh,with a capacity retention ratio(CRR)of only 66.08%.A linear relationship between the capacity retention ratio and thickness expansion was found.Electrochemical measurements and scanning electron microscope images demonstrate that intense stress inhibits the lithiation of the negative electrode and that the electrode is more susceptible to irreversible damage during cycling.Overall,these results reveal the relationship between the cycling performance of SiO and the internal pressure of the electrode from a macroscopic point of view,which provides some reference for the application of SiO/C composite electrodes in lithium-ion batteries.
文摘Electrospinning technology has emerged as a promising method for fabricating flexible lithium-ion batter-ies(FLIBs)due to its ability to create materials with desir-able properties for energy storage applications.FLIBs,which are foldable and have high energy densities,are be-coming increasingly important as power sources for wear-able devices,flexible electronics,and mobile energy applica-tions.Carbon materials,especially carbon nanofibers,are pivotal in improving the performance of FLIBs by increas-ing electrical conductivity,chemical stability,and surface area,as well as reducing costs.These materials also play a significant role in establishing conducting networks and im-proving structural integrity,which are essential for extend-ing the cycle life and enhancing the safety of the batteries.This review considers the role of electrospinning in the fabrication of critical FLIB components,with a particular emphasis on the integration of carbon materials.It explores strategies to optimize FLIB performance by fine-tuning the electrospinning para-meters,such as electric field strength,spinning rate,solution concentration,and carbonization process.Precise control over fiber properties is crucial for enhancing battery reliability and stability during folding and bending.It also highlights the latest research findings in carbon-based electrode materials,high-performance electrolytes,and separator structures,discussing the practical challenges and opportunities these materials present.It underscores the significant impact of carbon materials on the evolution of FLIBs and their potential to shape future energy storage technologies.
基金Project(2021H0028) supported by the Natural Scienceof Fujian Province,ChinaProject(JAT200455) supported by the Fujian Provincial Young and Middle-aged Teacher Education Project,ChinaProject(fma2023003) supported by the Open Fund of Fujian Provincial Key Laboratory of Functional Materials and Applications,China。
文摘Rich-nickel layered ternary NCM811 has been widely used in the field of electric vehicles ascribed to its high theoretical specific capacity.However,poor cycling stability and rate-performance hindered its further development.Herein,different amounts of nitrogen-doped carbon were wrapped on the surface of NCM811 via a facile rheological phase method by regulating the amount of dopamine hydrochloride.The effects of the coating amounts on the structure and electrochemical performance are investigated.The DFT calculation,XRD,SEM and XPS reveal that an appropriate amount of nitrogen-doped carbon coating could uniformly form a protective layer on the NCM811 surface and the introduced N could anchor Ni atoms to inhibit the Li^(+)/Ni^(2+)mixing,but excessive amount would reduce Ni^(3+)to Ni^(2+)so as to conversely aggravate Li^(+)/Ni^(2+)mixing.Among the samples,the NCM811-CN0.75 sample exhibits the most excellent electrochemical performance,delivering a high-rate capacity of 151.6 mA·h/g at 10C,and long-term cyclability with 82.2%capacity retention after 300 cycles at 5C,exhibiting remarkable rate-performance and cyclability.
基金Projects(51974137,52274299)supported by the National Natural Science Foundation of ChinaProject(2023M733190)supported by the China Postdoctoral Science Foundation。
文摘In view of the difference in coordination capacity of the glycine ion(Gly−),a selective leaching process for treating with spent lithium-ion batteries(LIBs)in the alkaline glycinate system was proposed.The effects of retention time,leaching temperature,concentration of glycine ligand,liquid-solid ratio(L/S),pH,stirring speed,and H_(2)O_(2) dosage on the leaching efficiency of valuable metals and the dissolution of impurities were investigated.When the spent LIBs were leached in 3 mol/L glycine aqueous solution with pH of 8,L/S of 5 mL:1 g and H_(2)O_(2) dosage of 5 vol.%at 90℃and stirring speed of 400 r/min for 3 h,lithium,cobalt,nickel,and manganese recoveries were 96.31%,83.18%,91.56%,and 31.16%,respectively,but Ca,Al,Fe,and Cu were almost insoluble.Meanwhile,the kinetic study showed that the activation energies for the leaching of Li,Co,Ni,and Mn were all in the range of 45−61 kJ/mol.The results indicate that the leaching process is all controlled by chemical reactions.
文摘The degradation process of lithium-ion batteries is intricately linked to their entire lifecycle as power sources and energy storage devices,encompassing aspects such as performance delivery and cycling utilization.Consequently,the accurate and expedient estimation or prediction of the aging state of lithium-ion batteries has garnered extensive attention.Nonetheless,prevailing research predominantly concentrates on either aging estimation or prediction,neglecting the dynamic fusion of both facets.This paper proposes a hybrid model for capacity aging estimation and prediction based on deep learning,wherein salient features highly pertinent to aging are extracted from charge and discharge relaxation processes.By amalgamating historical capacity decay data,the model dynamically furnishes estimations of the present capacity and forecasts of future capacity for lithium-ion batteries.Our approach is validated against a novel dataset involving charge and discharge cycles at varying rates.Specifically,under a charging condition of 0.25 C,a mean absolute percentage error(MAPE)of 0.29%is achieved.This outcome underscores the model's adeptness in harnessing relaxation processes commonly encountered in the real world and synergizing with historical capacity records within battery management systems(BMS),thereby affording estimations and prognostications of capacity decline with heightened precision.
基金the financial support from the National Natural Science Foundation of China (No. 21925403)the Excellent Research Program of Nanjing University (Grant No. ZYJH004)。
文摘Developing in situ spectroelectrochemistry methods,which can provide detailed information about species trans-formation during electrochemical reactions,is very important for studying electrode reaction mechanisms and improving battery performance.Studying real-time changes in the surface of electrode materials during normal operation can be an effective way to assess and optimize the practical performance of electrode materials,thus,in situ and in operando characterization techniques are particularly important.However,batteries are hard to be studied by in situ characterization measurements due to their hermetically sealed shells,and there is still much room for battery characterizations.In this work,a specially designed battery based on the structure of coin cells,whose upper cover was transparent,was constructed.With such a device,acquisition of diffuse reflectance spectra of electrode materials during charging and discharging was realized.This not only provided a simple measurement accessory for diffuse reflectance spectroscopy(DRS),but also complemented in situ characterization techniques for batteries.Taking commonly used cathode materials in lithium-ion batteries(LIBs),including LiFePO_(4)(LFP),NCM811 and LiCoO_(2)(LCO)as examples,we managed tofind out the response relationships of different electrode materials to visible light of different wavelengths under ordinary reflectance illumination conditions.Heterogeneity of different cathode ma-terials on interaction relationships with the lights of different wavelengths was also revealed.This work demonstrated the capability of guiding wavelength selection for different materials and assessing electrochemical performances of in situ diffuse reflectance spectroelectrochemistry.By combining electrochemistry with diffuse reflectance spectroscopy,this work made an effective complementary for spectroelectrochemistry.
文摘There is an urgent need for lithium-ion capacitors(LICs)that have both high energy and high power densities to meet the continuously growing energy storage demands.LICs effectively balance the high energy density of traditional rechargeable batteries with the superior power density and long life of supercapacitors(SCs).Nevertheless,the development of LICs is still hampered by limited kinetic processes and capacity mismatch between the cathode and anode.Metal-organic frameworks(MOFs)and their derivatives have received significant attention because of their extensive specific surface area,different pore structures and topologies,and customizable functional sites,making them compelling candidate materials for achieving high-performance LICs.MOF-derived carbons,known for their exceptional electronic conductivity and large surface area,provide improved charge storage and rapid ion transport.MOF-derived transition metal oxides contribute to high specific capacities and improved electrochemical stability.Additionally,MOF-derived metal compounds/carbons provide combined effects that increase both the capacitive and Faradaic reactions,leading to a superior overall performance.The review begins with an overview of the fundamental principles of LICs,followed by an exploration of synthesis strategies and ligand selection for MOF-based composite materials.It then analyzes the advantages of original MOFs and their derived materials,such as carbon materials and metal compounds,in enhancing LIC performance.Finally,the review discusses the major challenges faced by MOFs and their derivatives in LIC applications and offers future research directions and recommendations.
文摘In the development of rechargeable lithium ion batteries(LIBs),silicon anodes have attracted much attention because of their extremely high theoretical capacity,relatively low Li-insertion voltage and the availability of silicon resources.However,their large volume expansion and fragile solid electrolyte interface(SEI)film hinder their commercial application.To solve these problems,Si has been combined with various carbon materials to increase their structural stability and improve their interface properties.The use of different carbon materials,such as amorphous carbon and graphite,as three-dimensional(3D)protective anode coatings that help buffer mechanical strain and isolate the electrolyte is detailed,and novel methods for applying the coatings are outlined.However,carbon materials used as a protective layer still have some disadvantages,necessitating their modification.Recent developments have focused on modifying the protective carbon shells,and substitutes for the carbon have been suggested.
文摘Silicon anodes are promising for use in lithium-ion batteries.However,their practical application is severely limited by their large volume expansion leading to irreversible material fracture and electrical disconnects.This study proposes a new top-down strategy for preparing microsize porous silicon and introduces polyacrylonitrile(PAN)for a nitrogen-doped carbon coating,which is designed to maintain the internal pore volume and lower the expansion of the anode during lithiation and delithiation.We then explore the effect of temperature on the evolution of the structure of PAN and the electrochemical behavior of the composite electrode.After treatment at 400℃,the PAN coating retains a high nitrogen content of 11.35 at%,confirming the presence of C—N and C—O bonds that improve the ionic-electronic transport properties.This treatment not only results in a more intact carbon layer structure,but also introduces carbon defects,and produces a material that has remarkable stable cycling even at high rates.When cycled at 4 A g^(-1),the anode had a specific capacity of 857.6 mAh g^(-1) even after 200 cycles,demonstrating great potential for high-capacity energy storage applications.
基金funded by the National Natural Science Foundation of China(Grant No.12272217)。
文摘The aging characteristics of lithium-ion battery(LIB)under fast charging is investigated based on an electrochemical-thermal-mechanical(ETM)coupling model.Firstly,the ETM coupling model is established by COMSOL Multiphysics.Subsequently,a long cycle test was conducted to explore the aging characteristics of LIB.Specifically,the effects of charging(C)rate and cycle number on battery aging are analyzed in terms of nonuniform distribution of solid electrolyte interface(SEI),SEI formation,thermal stability and stress characteristics.The results indicate that the increases in C rate and cycling led to an increase in the degree of nonuniform distribution of SEI,and thus a consequent increase in the capacity loss due to the SEI formation.Meanwhile,the increases in C rate and cycle number also led to an increase in the heat generation and a decrease in the heat dissipation rate of the battery,respectively,which result in a decrease in the thermal stability of the electrode materials.In addition,the von Mises stress of the positive electrode material is higher than that of the negative electrode material as the cycling proceeds,with the positive electrode material exhibiting tensile deformation and the negative electrode material exhibiting compressive deformation.The available lithium ion concentration of the positive electrode is lower than that of the negative electrode,proving that the tensile-type fracture occurring in the positive material under long cycling dominated the capacity loss process.The aforementioned studies are helpful for researchers to further explore the aging behavior of LIB under fast charging and take corresponding preventive measures.
基金Project(2022YFC3900804)supported by the National Key Research and Development Program,ChinaProjects(2021JJ10058,2022JJ10074)supported by the Natural Science Foundation of Hunan Province of China。
文摘Recovering valuable metals from spent lithium-ion batteries(LIBs)for high value-added application is beneficial for global energy cycling and environmental protection.In this work,we obtain the high-performance N-doped Ni-Co-Mn(N-NCM)electrocatalyst from waste LIBs,for robust oxygen evolution application.Lithium-rich solution and NCM oxides are effectively separated from ternary cathode materials by sulfation roasting and low-temperature water leaching approach,in which the recovery efficiency of Li metal reaches nearly 100%.By facile NH_(3)treatment,the incorporation of N into NCM significantly increases the ratio of low-valence state Co^(2+)and Mn^(2+),and the formed Mn-N bond benefits the surface catalytic kinetics.Meanwhile,the N doping induces lattice expansion of the NCM,triggering tensile stress to favor the adsorption of the reactant.Thus,the optimized N-NCM electrocatalyst exhibits the superior overpotentials of 256 and 453 mV to achieve the current density of 10 and 100 mA/cm^(2),respectively,with a low Tafel slope of 37.3 mV/dec.This work provides a fresh avenue for recycling spent LIBs in the future to achieve sustainable development.
基金Project(2021JJ20062) supported by the Natural Science Foundation of Hunan Province,ChinaProject(2019XK2304) supported by Landmark Innovation Demonstration Project of Hunan Province,China+3 种基金Project(2022GK4058) supported by High-tech Industry Science and Technology Innovation Leading Project of Hunan Province,ChinaProject(2020CX038) supported by the Innovation Driven Project of Central South University,ChinaProject(2019YFC1907301) supported by the National Key R&D Program of ChinaProject(202006375018) supported by the China Scholarship Council。
文摘In this study,a roasting enhanced flotation process was proposed to recover LiMn_(2)O_(4) and grapite from waste lithium-ion batteries(LIBs).The effects of roasting temperature and time on the surface modification was investigated,and a series of analytical technologies were used to reveal process mechanism.The results indicate that LiMn_(2)O_(4) can be effectively separated from graphite via flotation after the roasting.The flotation grade of LiMn_(2)O_(4) was significantly increased from 63.10%to 91.36%after roasting at 550℃for 2 h.The TG-DTG analysis demonstrates that the difficulty in flotation separation of LiMn_(2)O_(4) from graphite is caused by the organic binder and electrolytes coating on their surfaces.The XRD,SEM,XPS,and contact angle analyses confirm that the organic films on the surfaces of those materials can be effectively removed by roasting,after which the wettability of LiMn_(2)O_(4) is regained and thus the surface wettability difference between the cathode and anode materials is increased significantly.The closed-circuit flotation test indicates that a LiMn_(2)O_(4) sample with high grade of 99.81%is obtained,while the recovery of LiMn_(2)O_(4) is as high as 99.40%.This study provides an economical and eco-friendly way to recycling waste LIBs.
基金Project(50803008)supported by the National Natural Science Foundation of ChinaProjects(14JJ4035,2011RS4067)supported by the Natural Science Foundation of Hunan Province,China+1 种基金Project(2013-sdllmd-08)supported by the State Key Laboratory of Luminescent Materials and Devices(South China University of Technology),ChinaProjects(20100480946,201104508)supported by the China Postdoctoral Science Foundation,China
文摘Single cell temperature difference of lithium-ion battery(LIB) module will significantly affect the safety and cycle life of the battery. The reciprocating air-flow module created by a periodic reversal of the air flow was investigated in an effort to mitigate the inherent temperature gradient problem of the conventional battery system with a unidirectional coolant flow with computational fluid dynamics(CFD). Orthogonal experiment and optimization design method based on computational fluid dynamics virtual experiments were developed. A set of optimized design factors for the cooling of reciprocating air flow of LIB thermal management was determined. The simulation experiments show that the reciprocating flow can achieve good heat dissipation, reduce the temperature difference, improve the temperature homogeneity and effectively lower the maximal temperature of the modular battery. The reciprocating flow improves the safety, long-term performance and life span of LIB.
基金Projects(51472211,51502256)supported by the National Natural Science Foundation of ChinaProjects(2016GK4005,2016GK4030)supported by the Strategic New Industry of Hunan Province,ChinaProject(13C925)supported by the Research Foundation of Education Bureau of Hunan Province,China
文摘Using low-cost FePO4·2H2O as iron source,Na2FePO4F/C composite is prepared by alcohol-assisted ball milling and solid-state reaction method.The XRD pattern of Na2FePO4F/C composite demonstrates sharp peaks,indicating high crystalline and phase purity.The SEM and TEM images reveal that diameter of the spherical-like Na2FePO4F/C particles ranges from 50 to 300 nm,and HRTEM image shows that the surface of Na2FePO4F/C composite is uniformly coated by carbon layer with a average thickness of about 3.6 nm.The carbon coating constrains the growth of the particles and effectively reduces the agglomeration of nanoparticles.Using lithium metal as anode,the composite delivers a discharge capacities of 102.8,96.4 and 90.3 mA·h/g at rates of 0.5C,1C and 2C,respectively.After 100 cycles at 0.5C,a discharge capacity of 98.9 mA·h/g is maintained with capacity retention of 96.2%.The Li+diffusion coefficient(D)of Na2FePO4F/C composite is calculated as 1.71×10^–9 cm^2/s.This study reveals that the simple solid state reaction could be a practical and effective synthetic route for the industrial production of Na2FePO4F/C material.
基金Project(50905015) supported by the National Natural Science Foundation of China
文摘In order to characterize the voltage behavior of a lithium-ion battery for on-board electric vehicle battery management and control applications,a battery model with a moderate complexity was established.The battery open circuit voltage (OCV) as a function of state of charge (SOC) was depicted by the Nernst equation.An equivalent circuit network was adopted to describe the polarization effect of the lithium-ion battery.A linear identifiable formulation of the battery model was derived by discretizing the frequent-domain description of the battery model.The recursive least square algorithm with forgetting was applied to implement the on-line parameter calibration.The validation results show that the on-line calibrated model can accurately predict the dynamic voltage behavior of the lithium-ion battery.The maximum and mean relative errors are 1.666% and 0.01%,respectively,in a hybrid pulse test,while 1.933% and 0.062%,respectively,in a transient power test.The on-line parameter calibration method thereby can ensure that the model possesses an acceptable robustness to varied battery loading profiles.
