lithium ion battery

摘要： The particle morphology determined by the sintering process is the director factor affecting the electrochemical performance of Ni-rich NMC cathode materials.To prepare the ideal NMC particles,it is of great significance to understand the morphological changes during sintering process.In this work,the morphology evolution of LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)(NMC811)synthesis at temperature ranging from 300–1080°Cwere observed by in situ SEM.The uniform mixture of spherical Ni_(0.8)Mn_(0.1)Co_(0.1)(OH)_(2)precursor and lithium sources(LiOH)was employed by high temperature solid-state process inside the SEM,which enables us to observe morphology changes in real time.The results show that synthetic reaction of LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)usually includes three processes:the raw materials’dehydration,oxidation,and combination,accompanied by a significant reduction in particle size,which is important reference to control the synthesis temperature.As heating temperature rise,the morphology of mixture also changed from flake to brick-shaped.However,Ni nanoparticle formation is apparent at higher temperature~1000°C,suggesting a structural transformation from a layered to a rock-salt-like structure.Combining the in-situ observed changes in size and morphology,and with the premise of ensuring the morphology change from flakes to bricks,reducing the sintering temperature as much as possible to prevent excessive reduction in particle size and layered to a rock-salt structure transformation is recommended for prepare ideal NMC particles.

摘要： In 2011,a new class of 2D materials was discovered;after 2012,they began to be concerned;in 2017,the“gold rush”of the materials was triggered,and they are exactly MXenes.2D MXenes,a new class of transition metal carbides,carbonitrides and nitrides,have become the star and cutting-edge research materials in the field of emerging batteries systems due to their unique 2D structure,abundant surface chemistry,and excellent physical and electrochemical properties.This review focuses on the MXene materials and summarizes the recent advancements in the synthesis techniques and properties,in addition to a detailed discussion on the electrochemical energy storage applications,including alkali-ion(Li^(+),Na^(+),K^(+))storage,lithium-sulfur(Li–S)batteries,sodiumsulfur(Na–S)batteries,and metal anode protection.Special attentions are given to the elaborate design of nano-micro structures of MXenes for the various roles as electrodes,multifunctional components,S hosts,modified separators,and metal anode protective layers.The paper ends with a prospective summary of the promising research directions in terms of synthesis,structure,properties,analysis,and production on MXene materials.

摘要： The safety monitoring of lithium-ion batteries(LIBs) is of great significance for realizing all-climate and full-lifespan battery management. In-situ measurement of anode potential with implanted reference electrodes(REs) has proven to be effective to monitor and avoid the occurrence of severe side reactions like Li plating to ensure the safe and fast charging. However, the intrinsic measurement errors caused by local blocking effects, which also can be referred to as potential artefacts, are seldom taken into consideration in existing studies, yet they highly dominate the correctness of conclusions inferred from REs. In this study, aiming at exploring the physical origin of the measurement errors and ensure reliable potential monitoring, electrochemical and post-mortem tests are conducted using commercial pouch cells with implanted REs. Corresponding electrochemical model which describes the blocking effects, is established to validate the abnormal absence of lithium plating that predicted by measured anode potentials under various charging rates. Theoretical derivation is further presented to explain the error sources, which can be attributed to increased local liquid potential of the RE position. Most importantly, with the guidance of error analysis, a novel parameter-independent error correction method for RE measurements is proposed for the first time, which is proven to be adequate to estimate the real anode potentials and deduce the critical C-rate of Li plating with extra safety margin. After error correction, the resulting critical C-rates are all within the range of 0.55 ± 0.03 C, which is close to the C-rate of 0.6–0.7 C obtained from experiments. In addition, this error correction method can be performed conveniently with only some simple RE measurements of polarization voltages, totally independent of battery electrochemical and geometric parameters. This study provides highly practical error correction method for RE measurements in real LIBs, substantially facilitating the fast diagnosis and safety evaluation of Li plating during charging of LIBs.

摘要： Laser-structuring is an effective method to promote ion diffusion and improve the performance of lithium-ion battery(LIB)electrodes.In this work,the effects of laser structuring parameters(groove pitch and depth)on the fundamental characteristics of LIB electrode,such as interfacial area,internal resistances,material loss and electrochemical performance,are investigated,LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2) cathodes were structured by a femtosecond laser by varying groove depth and pitch,which resulted in a material loss of 5%-14%and an increase of 140%-260%in the in terfacial area between electrode surface and electrolyte.It is shown that the importance of groove depth and pitch on the electrochemical performance(specific capacity and areal discharge capacity)of laser-structured electrode varies with current rates.Groove pitch is more im porta nt at low current rate but groove depth is at high curre nt rate.From the mapping of lithium concentration within the electrodes of varying groove depth and pitch by laser-induced breakdown spectroscopy,it is verified that the groove functions as a diffusion path for lithium ions.The ionic,electronic,and charge transfer resistances measured with symmetric and half cells showed that these internal resistances are differently affected by laser structuring parameters and the changes in porosity,ionic diffusion and electronic pathways.It is demonstrated that the laser structuring parameters for maximum electrode performance and minimum capacity loss should be determined in consideration of the main operating conditions of LIBs.

摘要： The 3d transition-metal nickel(Ni)-based cathodes have long been widely used in rechargeable batteries for over 100 years,from Ni-based alkaline rechargeable batteries,such as nickel-cadmium(Ni-Cd)and nickel-metal hydride(Ni-MH)batteries,to the Ni-rich cathode featured in lithium-ion batteries(LIBs).Ni-based alkaline batteries were first invented in the 1900s,and the well-developed Ni-MH batteries were used on a large scale in Toyota Prius vehicles in the mid-1990s.Around the same time,however,Sony Corporation commercialized the first LIBs in camcorders.After temporally fading as LiCoO_(2) dominated the cathode in LIBs,nickel oxide-based cathodes eventually found their way back to the mainstreaming battery industry.The uniqueness of Ni in batteries is that it helps to deliver high energy density and great storage capacity at a low cost.This review mainly provides a comprehensive overview of the key role of Ni-based cathodes in rechargeable batteries.After presenting the physical and chemical properties of the 3d transition-metal Ni,which make it an optimal cationic redox center in the cathode of batteries,we introduce the structure,reaction mechanism,and modification of nickel hydroxide electrode in Ni-Cd and Ni-MH rechargeable batteries.We then move on to the Ni-based layered oxide cathode in LIBs,with a focus on the structure,issues,and challenges of layered oxides,LiNiO_(2),and LiNi_(1−x−y)Co_(x)Mn_(y)O_(2).The role of Ni in the electrochemical performance and thermal stability of the Ni-rich cathode is highlighted.By bridging the“old”Ni-based batteries and the“modern”Ni-rich cathode in the LIBs,this review is committed to providing insights into the Ni-based electrochemistry and material design,which have been under research and development for over 100 years.This overview would shed new light on the development of advanced Ni-containing batteries with high energy density and long cycle life.

摘要： Tris(trimethylsilyl)borate(TMSB) has been intensively studied to improve the performances of lithiumion batteries. However, it is still an interesting issue needed to be resolved for the research on the Li^(+) solvation structure affected by TMSB additive. Herein, the electrochemical tests, quantum chemistry calculations, potential-resolved in-situ electrochemical impedance spectroscopy measurements and surface analyses were used to explore the effects of Li^(+) solvation structure with TMSB additive on the formation of the cathode electrolyte interface(CEI) film in LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)/Li half cells. The results reveal that the TMSB additive is easy to complex with Li^(+) ion, thus weaken the intermolecular force between Li^(+) ions and ethylene carbonate solvent, which is benefit for the cycle performance. Besides, the changed Li^(+) solvation structure results in a thin and dense CEI film containing compounds with Si–O and B–O bonds which is favorable to the transfer of Li^(+) ions. As a result, the performances of the LNCM811/Li half cells are effectively improved. This research provides a new idea to construct a high-performance CEI film by adjusting the Li^(+) solvation structures.

摘要： A flexible anode composite,carbon cloth@SiO_(2)composite(CC@SiO_(2)),was synthesized by a one-step solution method using tetraethyl orthosilicate(TEOS)as the silica source.CC@SiO_(2)can be directly used as the negative electrode material for lithium-ion battery,and its initial reversible deintercalation capacity reaches 1358.7 mA·h·g^(-1).The electrode shows a capacity of 863.8 mA·h·g^(-1)up to 130 cycles at 0.5 A·g^(-1),displaying excellent rate performance and cycle stability.

摘要： A facile injected pyrolysis strategy to synthesize heteroatom-doped carbon spheres(CSs) with good conductivity is proposed by using the fluid catalytic cracking slurry oil(FCCSO) as the carbon source through a pyrolysis reaction process at 700-1000°C.The structures of CSs are characterized by scanning electron microscopy(SEM),transmission electron microscopy(TEM),X-ray diffraction(XRD),Raman spectroscopy,Fourier transform infrared spectroscopy(FT-IR) and X-ray photoelectron spectroscopy(XPS).The effect of preparation conditions on the morphology and its electrochemical properties of CSs acting as the anode material for lithium-ion battery(LIBs) are investigated.The XPS measurement results show that the CSs mainly contain C,N,O,and S elements.With the increase of pyrolysis temperature,the particle size of CSs decreases but the graphitization degree of CSs increases.As the anode material for LIBs,CSs show excellent electrochemical performance with a maximum reversible capacity of 365 mAh/g and an initial coulombic efficiency of 73.8% at a low current density of 50 mA/g.The CSs exhibit excellent cycling stability in a current range of 50 mA/g to 2 A/g,and still can maintain a stable reversible capacity of 347 mAh/g when the current is cycled back to 50mA/g.This is mainly ascribed to the existence of suitable heteroatom content and unique spherical structure of CSs.The heteroatom-doped CSs can provide a new choice for the preparation of high efficiency anode materials for LIBs.

摘要： Relieving the stress or strain associated with volume change is highly desirable for high-performance SiOx anodes in terms of stable solid electrolyte interphase(SEI)-film growth.Herein,a Si-valence gradient is optimized in SiOx composites to circumvent the large volume strain accompanied by lithium insertion/extraction.SiO_(x)@C annealed at 850°C has a gentle Si-valence gradient along the radial direction and excellent electrochemical performances,delivering a high capacity of 506.9 mAh g^(−1) at 1.0 A g^(−1) with a high Coulombic efficiency of~99.8%over 400 cycles.Combined with the theoretical prediction,the obtained results indicate that the gentle Si-valence gradient in SiO_(x)@C is useful for suppressing plastic deformation and maintaining the inner connection integrity within the SiO_(x)@C particle.Moreover,a gentle Si-valence gradient is expected to form a stress gradient and affect the distribution of dangling bonds,resulting in local stress relief during the lithiation/delithiation process and enhanced Li-ion kinetic diffusion.Furthermore,the lowest interfacial stress variation ensures a stable SEI film at the interface and consequently increases cycling stability.Therefore,rational design of a Si-valence gradient in SiOx can provide further insights into achieving high-performance SiOx anodes with large-scale production.

摘要： As important ingredients in lithium-ion battery,the Coulombic efficiency and power density greatly impact the electrochemical performances.Although recent literatures have reported nano-porous materials to enhance the specific capacities,intrinsic drawbacks such as poor initial Coulombic efficiency and low volumetric capacity could not be avoided.Herein,we propose a strategy to prepare carbon supported MoO_(2)spheres used for lithium-ion battery with high volumetric capacity density.A high initial Coulombic efficiency of 76.5%is obtained due to limited solid electrolyte interface film formed on the exposed surface.Meantime,the sample with an optimal carbon content and a proper structural strength reveals a higher reversible capacity of 956 mA h g^(-1)than the theoretical capacity of crystalline Mo O_(2)(838 mA h g^(-1))and a high capacity retention ratio of 96.4%after 100 cycles at 0.5 A g^(-1).And an effective compaction capacity density(under 5 MPa)of 670 mA h cm^(-3)of the spheres proves its potential value in practical applications.

摘要： A series of the electrode materials (LiCoO2) for Lithium ion batteries were synthesized by radiating the mixture of Lithium oxide and Cobalt oxide in microwave field. The synthesizing conditions including reaction time, output power and reaction temperature were examned. And in the mean time, the structure and properties of LiCoO2 was characterized by using XRD, SEM technology and electrochemical testing method. The results showed that the output power and reaction time had a significant effect on the structure of products and that, the ordering layered structure of LiCoO2 had been obtained. In the tests of charge-discharge, it was found that the discharge capability of the first cycle was as high as 140mAhg-1. In comparison with conventional synthetic method, the microwave method can be energysaving, efficient with specious and clean working environment.

摘要： A series of the electrode materials (LiCoO2) for Lithium ion batteries were synthesized by radiating the mixture of Lithium oxide and Cobalt oxide in microwave field. The synthesizing conditions including reaction time, output power and reaction temperature were examned. And in the mean time, the structure and properties of LiCoO2 was characterized by using XRD, SEM technology and electrochemical testing method. The results showed that the output power and reaction time had a significant effect on the structure of products and that, the ordering layered structure of LiCoO2 had been obtained. In the tests of charge-discharge, it was found that the discharge capability of the first cycle was as high as 140mAhg-1. In comparison with conventional synthetic method, the microwave method can be energysaving, efficient with specious and clean working environment.

摘要： A series of the electrode materials (LiCoO2) for Lithium ion batteries were synthesized by radiating the mixture of Lithium oxide and Cobalt oxide in microwave field. The synthesizing conditions including reaction time, output power and reaction temperature were examned. And in the mean time, the structure and properties of LiCoO2 was characterized by using XRD, SEM technology and electrochemical testing method. The results showed that the output power and reaction time had a significant effect on the structure of products and that, the ordering layered structure of LiCoO2 had been obtained. In the tests of charge-discharge, it was found that the discharge capability of the first cycle was as high as 140mAhg-1. In comparison with conventional synthetic method, the microwave method can be energysaving, efficient with specious and clean working environment.

摘要： A series of the electrode materials (LiCoO2) for Lithium ion batteries were synthesized by radiating the mixture of Lithium oxide and Cobalt oxide in microwave field. The synthesizing conditions including reaction time, output power and reaction temperature were examned. And in the mean time, the structure and properties of LiCoO2 was characterized by using XRD, SEM technology and electrochemical testing method. The results showed that the output power and reaction time had a significant effect on the structure of products and that, the ordering layered structure of LiCoO2 had been obtained. In the tests of charge-discharge, it was found that the discharge capability of the first cycle was as high as 140mAhg-1. In comparison with conventional synthetic method, the microwave method can be energysaving, efficient with specious and clean working environment.

摘要： A series of the electrode materials (LiCoO2) for Lithium ion batteries were synthesized by radiating the mixture of Lithium oxide and Cobalt oxide in microwave field. The synthesizing conditions including reaction time, output power and reaction temperature were examned. And in the mean time, the structure and properties of LiCoO2 was characterized by using XRD, SEM technology and electrochemical testing method. The results showed that the output power and reaction time had a significant effect on the structure of products and that, the ordering layered structure of LiCoO2 had been obtained. In the tests of charge-discharge, it was found that the discharge capability of the first cycle was as high as 140mAhg-1. In comparison with conventional synthetic method, the microwave method can be energysaving, efficient with specious and clean working environment.

摘要： A series of the electrode materials (LiCoO2) for Lithium ion batteries were synthesized by radiating the mixture of Lithium oxide and Cobalt oxide in microwave field. The synthesizing conditions including reaction time, output power and reaction temperature were examned. And in the mean time, the structure and properties of LiCoO2 was characterized by using XRD, SEM technology and electrochemical testing method. The results showed that the output power and reaction time had a significant effect on the structure of products and that, the ordering layered structure of LiCoO2 had been obtained. In the tests of charge-discharge, it was found that the discharge capability of the first cycle was as high as 140mAhg-1. In comparison with conventional synthetic method, the microwave method can be energysaving, efficient with specious and clean working environment.

摘要： A series of the electrode materials (LiCoO2) for Lithium ion batteries were synthesized by radiating the mixture of Lithium oxide and Cobalt oxide in microwave field. The synthesizing conditions including reaction time, output power and reaction temperature were examned. And in the mean time, the structure and properties of LiCoO2 was characterized by using XRD, SEM technology and electrochemical testing method. The results showed that the output power and reaction time had a significant effect on the structure of products and that, the ordering layered structure of LiCoO2 had been obtained. In the tests of charge-discharge, it was found that the discharge capability of the first cycle was as high as 140mAhg-1. In comparison with conventional synthetic method, the microwave method can be energysaving, efficient with specious and clean working environment.

摘要： A series of the electrode materials (LiCoO2) for Lithium ion batteries were synthesized by radiating the mixture of Lithium oxide and Cobalt oxide in microwave field. The synthesizing conditions including reaction time, output power and reaction temperature were examned. And in the mean time, the structure and properties of LiCoO2 was characterized by using XRD, SEM technology and electrochemical testing method. The results showed that the output power and reaction time had a significant effect on the structure of products and that, the ordering layered structure of LiCoO2 had been obtained. In the tests of charge-discharge, it was found that the discharge capability of the first cycle was as high as 140mAhg-1. In comparison with conventional synthetic method, the microwave method can be energysaving, efficient with specious and clean working environment.

摘要： A series of the electrode materials (LiCoO2) for Lithium ion batteries were synthesized by radiating the mixture of Lithium oxide and Cobalt oxide in microwave field. The synthesizing conditions including reaction time, output power and reaction temperature were examned. And in the mean time, the structure and properties of LiCoO2 was characterized by using XRD, SEM technology and electrochemical testing method. The results showed that the output power and reaction time had a significant effect on the structure of products and that, the ordering layered structure of LiCoO2 had been obtained. In the tests of charge-discharge, it was found that the discharge capability of the first cycle was as high as 140mAhg-1. In comparison with conventional synthetic method, the microwave method can be energysaving, efficient with specious and clean working environment.