Machine learning in metal-ion battery research: Advancing material prediction, characterization, and status evaluation

Metal-ion batteries(MIBs),including alkali metal-ion(Li^(+),Na^(+),and K^(3)),multi-valent metal-ion(Zn^(2+),Mg^(2+),and Al^(3+)),metal-air,and metal-sulfur batteries,play an indispensable role in electrochemical energy storage.However,the performance of MIBs is significantly influenced by numerous variables,resulting in multi-dimensional and long-term challenges in the field of battery research and performance enhancement.Machine learning(ML),with its capability to solve intricate tasks and perform robust data processing,is now catalyzing a revolutionary transformation in the development of MIB materials and devices.In this review,we summarize the utilization of ML algorithms that have expedited research on MIBs over the past five years.We present an extensive overview of existing algorithms,elucidating their details,advantages,and limitations in various applications,which encompass electrode screening,material property prediction,electrolyte formulation design,electrode material characterization,manufacturing parameter optimization,and real-time battery status monitoring.Finally,we propose potential solutions and future directions for the application of ML in advancing MIB development.

Steric hindrance shielding viologen against alkali attack in realizing ultrastable aqueous flow batteries

Viologens known as a kind of promising negolyte materials for aqueous organic redox flow batteries,face a critical stability challenge due to the S_N2 nucleophilic attack by hydroxide ions(OH-)during the battery cycling.In this work,a N-cyclic quaternary ammonium-grafted viologen molecule,viz.1,1'-bis(4,4'-dime thylpiperidiniumyl)-4,4'-bipyridinium tetrachloride((DBPPy)Cl_(4)),is developed by the molecular engineering strategy.The obtained(DBPPy)Cl_(4) molecule shows a decent solubility of 1.84 M and a redox potential of-0.52 V vs.Ag/AgCl,Experimental and theoretical results reveal that the grafted N-cyclic quaternary ammonium groups act as the steric hindrance to prevent nucleophilic attack by OH~-,increasing the alkali resistance of the electroactive molecule.The symmetrical battery with 0.50 M(DBPPy)Cl4shows negligible decay during the 13-day cycling test.As demonstration,the flow battery utilizing 1.0 M(DBPPy)Cl_(4) as the negolyte and 1-(1-oxyl-2,2',6,6'-tetramethylpiperidin-4-yl)-1'-(3-(trimethylammonio)propyl)-4,4'-bipyridinium trichloride as the posolyte exhibits a high capacity retention rate of 99.99%per cycle at 60 mA cm^(-2).

Application of deep learning for informatics aided design of electrode materials in metal-ion batteries

To develop emerging electrode materials and improve the performances of batteries,the machine learning techniques can provide insights to discover,design and develop battery new materials in high-throughput way.In this paper,two deep learning models are developed and trained with two feature groups extracted from the Materials Project datasets to predict the battery electrochemical performances including average voltage,specific capacity and specific energy.The deep learning models are trained with the multilayer perceptron as the core.The Bayesian optimization and Monte Carlo methods are applied to improve the prediction accuracy of models.Based on 10 types of ion batteries,the correlation coefficients are maintained above 0.9 compared to DFT calculation results and the mean absolute error of the prediction results for voltages of two models can reach 0.41 V and 0.20 V,respectively.The electrochemical performance prediction times for the two trained models on thousands of batteries are only 72.9 ms and 75.7 ms.Besides,the two deep learning models are applied to approach the screening of emerging electrode materials for sodium-ion and potassium-ion batteries.This work can contribute to a high-throughput computational method to accelerate the rational and fast materials discovery and design.

The design and engineering strategies of metal tellurides for advanced metal-ion batteries

Owning various crystal structures and high theoretical capacity,metal tellurides are emerging as promising electrode materials for high-performance metal-ion batteries(MBs).Since metal telluride-based MBs are quite new,fundamental issues raise regarding the energy storage mechanism and other aspects affecting electrochemical performance.Severe volume expansion,low intrinsic conductivity and slow ion diffusion kinetics jeopardize the performance of metal tellurides,so that rational design and engineering are crucial to circumvent these disadvantages.Herein,this review provides an in-depth discussion of recent investigations and progresses of metal tellurides,beginning with a critical discussion on the energy storage mechanisms of metal tellurides in various MBs.In the following,recent design and engineering strategies of metal tellurides,including morphology engineering,compositing,defect engineering and heterostructure construction,for high-performance MBs are summarized.The primary focus is to present a comprehensive understanding of the structural evolution based on the mechanism and corresponding effects of dimension control,composition,electron configuration and structural complexity on the electrochemical performance.In closing,outlooks and prospects for future development of metal tellurides are proposed.This work also highlights the promising directions of design and engineering strategies of metal tellurides with high performance and low cost.

A comprehensive overview of the electrochemical mechanisms in emerging alkali metal-carbon dioxide batteries

Alkali metal-carbon dioxide(Li/Na/K-CO_(2))batteries are emerging electrochemical energy storage technologies in the context of the energy crisis and the urgent demand for carbon neutrality.Alkali metal-CO_(2) batteries offer a new strategy for CO_(2) fixation and utilization,and thus has been receiving considerable attention in recent years.Considerable progress has been achieved since alkali metal-CO_(2) batteries were invented,especially in terms of development of new electrode materials,and yet,research is lacking on the underlying mechanisms of the systems.This is the first typical review focusing on the electrochemical mechanisms of metal-CO_(2) batteries that summarizes the current understanding of and provides insights into the thermodynamic reaction pathways,the kinetic characteristics,and the crucial factors determining the reaction mechanisms in alkali metal-CO_(2) batteries.The review starts with the fundamental concepts of alkali metal-CO_(2) batteries,followed by a comprehensive discussion of the working mechanisms on cathodes and anodes.Moreover,the operation mechanisms of state-of-the-art electrolytes,including liquid and(quasi-)solid-state electrolytes,are also described.Finally,we identify the unsolved problems in current alkali metal-CO_(2) batteries and propose potential topics for future research.

Designing Advanced Liquid Electrolytes for Alkali Metal Batteries:Principles,Progress,and Perspectives

The ever-growing pursuit of high energy density batteries has triggered extensive efforts toward developing alkali metal(Li,Na,and K)battery(AMB)technologies owing to high theoretical capacities and low redox potentials of metallic anodes.Typically,for new battery systems,the electrolyte design is critical for realizing the battery electrochemistry of AMBs.Conventional electrolytes in alkali ion batteries are generally unsuitable for sustaining the stability owing to the hyper-reactivity and dendritic growth of alkali metals.In this review,we begin with the fundamentals of AMB electrolytes.Recent advancements in concentrated and fluorinated electrolytes,as well as functional electrolyte additives for boosting the stability of Li metal batteries,are summarized and discussed with a special focus on structure-composition-performance relationships.We then delve into the electrolyte formulations for Na-and K metal batteries,including those in which Na/K do not adhere to the Li-inherited paradigms.Finally,the challenges and the future research needs in advanced electrolytes for AMB are highlighted.This comprehensive review sheds light on the principles for the rational design of promising electrolytes and offers new inspirations for developing stable AMBs with high performance.

Structural engineering of potassium vanadate cathode by pre-intercalated Mg_(2+) for high-performance and durable rechargeable aqueous zinc-ion batteries

Aqueous zinc(Zn)-ion batteries(AZIBs)have the potential to be used in massive energy storage owing to their low cost,eco-friendliness,safety,and good energy density.Significant research has been focused on enhancing the performance of AZIBs,but challenges persist.Vanadium-based oxides,known for their large interlayer spacing,are promising cathode materials.In this report,we synthesize Mg^(2+)-intercalated potassium vanadate(KVO)(MgKVO)via a single-step hydrothermal method and achieve a 12.2°Ainterlayer spacing.Mg^(2+) intercalation enhances the KVO performance,providing wide channels for Zn^(2+),which results in high capacity and ion diffusion.The combined action of K^(+) and Mg^(2+) intercalation enhances the electrical conductivity of MgKVO.This structural design endows MgKVO with excellent electrochemical performance.The AZIB with the MgKVO cathode delivers a high capacity of 457 mAh g^(-1) at 0.5 A g^(-1),excellent rate performance of 298 mAh g^(-1) at 5 A g^(-1),and outstanding cycling stability of 102%over 1300 cycles at 3 A g^(-1).Additionally,pseudocapacitance analysis reveals the high capacitance contribution and Zn^(2+)diffusion coefficient of MgKVO.Notably,ex-situ X-ray diffraction,X-ray photoelectron spectroscopy,and Raman analyses further demonstrate the Zn^(2+)insertion/extraction and Zn-ion storage mechanisms that occurred during cycling in the battery system.This study provides new insights into the intercalation of dual cations in vanadium oxides and offers new solutions for designing cathodes for high-capacity AZIBs.

Two-dimensional organic cathode materials for alkali-metal-ion batteries

With the increasing demand for large-scale battery systems in electric vehicles（EVs） and smart renewable energy grids, organic materials including small molecules and polymers utilized as electrodes in rechargeable batteries have received increasing attraction. In recent years, two-dimensional（2D） organic materials possessing planar layered architecture exhibit optional chemical modification, high specific surface area as well as unique electrical/magnetic properties, which have been emerging as the promising functional materials for wide applications in optoelectronics, catalysis, sensing, etc. Integrating with high-density redox-active sites and hierarchical porous structure, significant achievements in 2D organic materials as cathode materials for alkali-metal-ion batteries have been witnessed. In this review, the recent progress in synthetic approaches, structure analyses, electrochemical characterizations of 2D organic materials as well as their application in alkali-metal-ion batteries containing lithium ion battery（LIB）, lithium sulfur battery（LSB）, lithium air battery（LAB） and sodium ion battery（SIB） are summarized systematically,and their current challenges including cycling stability and electron conductivity for cathode materials in battery fields are also discussed.

Residual alkali-evoked cross-linked polymer layer for anti-air-sensitivity LiNi_(0.89)Co_(0.06)Mn_(0.05)O_(2)cathode

High-energy density lithium-ion batteries(LIBs)with layered high-nickel oxide cathodes(LiNi_(x)Co_(y)Mn_(1-x-y)O_(2),x≥0.8)show great promise in consumer electronics and vehicular applications.However,LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)faces challenges related to capacity decay caused by residual alkalis owing to high sensitivity to air.To address this issue,we propose a hazardous substances upcycling method that fundamentally mitigates alkali content and concurrently induces the emergence of an anti-air-sensitive layer on the cathode surface.Through the neutralization of polyacrylic acid(PAA)with residual alkalis and then coupling it with 3-aminopropyl triethoxysilane(KH550),a stable and ion-conductive cross-linked polymer layer is in situ integrated into the LiNi_(0.89)Co_(0.06)Mn_(0.05)O_(2)(NCM)cathode.Our characterization and measurements demonstrate its effectiveness.The NCM material exhibits impressive cycling performance,retaining 88.4%of its capacity after 200 cycles at 5 C and achieving an extraordinary specific capacity of 170.0 mA h g^(-1) at 10 C.Importantly,this layer on the NCM efficiently suppresses unfavorable phase transitions,severe electrolyte degradation,and CO_(2)gas evolution,while maintaining commendable resistance to air exposure.This surface modification strategy shows widespread potential for creating air-stable LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)cathodes,thereby advancing high-performance LIBs.

Recent progress in rechargeable alkali metal-air batteries

Rechargeable alkali metal-air batteries are considered as the most promising candidate for the power source of electric vehicles(EVs) due to their high energy density. However, the practical application of metal-air batteries is still challenging. In the past decade, many strategies have been purposed and explored, which promoted the development of metal-air batteries. The reaction mechanisms have been gradually clarified and catalysts have been rationally designed for air cathodes. In this review, we summarize the recent development of alkali metal-air batteries from four parts: metal anodes, electrolytes, air cathodes and reactant gases, wherein we highlight the important achievement in this filed. Finally problems and prospective are discussed towards the future development of alkali metal-air batteries.

Gallium-based anodes for alkali metal ion batteries

Alkali metal ion batteries(AMIBs)are playing an irreplaceable part in the energy revolution,due to their intrinsic advantages of large capacity/power density and abundance of alkali metal ions in the earth’s crust.Despite their great promise,the inborn deficiencies of commercial graphite and other anodes being researched so far call for the quest of better alternatives that exhibit all-round performance with the balance of energy/power density and cycling stability.Gallium-based materials,with impressive capacity utilization and self-healing ability,provide an anticipated solution to this conundrum.In this review,an overview on the recent progress of gallium-based anodes and their storage mechanism is presented.The current strategies used as engineering solutions to meet the scientific challenges ahead are discussed,in addition to the insightful outlook for possible future study.

First-principles study on β-GeS monolayer as high performance electrode material for alkali metal ion batteries

Based on the density functional theory calculations,we have investigated the feasibility of two-dimensionalβ-GeS monolayer as high-performance anodes for alkali metal ion batteries.The results show that the electrical conductivity of β-GeS monolayer can be enhanced after adsorbing the alkali metal atoms owing to the semiconductor-to-metal transition.The low diffusion barriers of alkali metal atoms on the β-GeS surface indicate a rapid charge/discharge rate without metal clustering.Moreover,the low average open-circuit voltage(0.211 V)and a high theoretical capacity(1024 mAh·g^(-1))for Na suggest that theβ-GeS monolayer is a promising anode material for Na-ion batteries with high performance.

Revealing the structure design of alloyed based electrodes for alkali metal ion batteries with in situ TEM

Alloyed based anode materials with high theoretical specific capacity and low reaction potential are considered to be highly potential high-energy density anode materials for alkali metal ion batteries(AMIBs).Thus,the design of alloyed based materials with high electrochemical performance has attracted great attention.Among the numerous characterization methods for guiding electrode materials design,in situ transmission electron microscopy(TEM)gradually plays an irreplaceable role due to its high temporal and spatial resolution in directly observing the change of morphology,crystal structure and element evolutions.Herein,we reviewed the two current research hotspots and mainly focused on the structure design of alloyed based electrode material under the guidance of in situ TEM.Specifically,various nanostructure designs of alloyed based electrode materials with guidance of in situ TEM were employed to solve the key scientific issues of the violent volume change during alloying/dealloying processes for enhanced electrochemical performances.Mainly through introducing buffer space in the electrode material to reduce volume change to improve structural stability,including porous structure(0 D),nanotube structure(1 D),simple hollow structure,yolk-shell structure and some hybrid hollow structures(3 D).Furthermore,the direct guidance of in situ TEM is expected for creating new opportunities to nextgeneration electrode material design for AMIBs.

Design strategies for rechargeable aqueous metal-ion batteries

Rechargeable aqueous metal-ion batteries(AMBs)have attracted extensive scientific and commercial interest due to their potential for cost-effective,highly safe,and scalable stationary energy storage.However,their limited output voltage,inadequate energy density,and poor reversibility of ambiguous electrode reactions in aqueous electrolytes strongly limit their practical viability.This review aims to elucidate the challenges of existing AMBs from the material design to whole device applications.We summarize the emerging electrochemistry,fundamental properties,and key issues in interfacial behaviors of various classes of prevailing AMBs,including aqueous alkali metal-ion batteries and multivalent-ion batteries,and present an appraisal of recent advances for addressing the performance deficiency.Specifically,the progress of zinc-ion batteries is highlighted to provide a ubiquitous guideline for their commercialization in the grid-scale energy storage.Finally,we figure out the dominating general challenges for achieving high-performance AMBs,laying out a perspective for future breakthroughs.

废旧磷酸铁锂电池集流体分离与正极材料再生

通过优化NaOH碱溶条件高效去除集流体黏结剂,保留完整铝箔;利用固相法再生LiFePO 4。当NaOH为0.8 mol/L、固液比20 mL/g、40℃反应10 min,正极材料的分离率达到99.78%,超声1 min后铝箔回收率为76%,解决了碱溶条件下铝箔回收的繁琐问题。球磨转速500 r、球磨5 h,补充10%高纯LiFePO 4的方式固相再生,再生LiFePO 4的最高放电比容量为新材料的94.75%,60次循环测试后为初始放电比容量的88.62%。

Recent Advances in Covalent Organic Framework Electrode Materials for Alkali Metal-Ion Batteries

Owing to the shortcomings of traditional electrode materials in alkalimetal-ion batteries(AIBs),such as limited reversible specific capacity,low power density,and poor cycling performance,it is particularly important to develop new electrode materials.Covalent organic frameworks(COFs)are crystalline porous polymers that incorporate organic building blocks into their periodic structures through dynamic covalent bonds.COFs are superior to organic materials because of their high designability,regular channels,and stable topology.Since the first report of D_(TP)-A_(NDI)-COF as a cathode material for lithium-ion batteries in 2015,research on COF electrode materials has made continuous progress and breakthroughs.This review briefly introduces the characteristics and current challenges associated with COF electrode materials.Furthermore,we summarize the basic reaction types and active sites according to the categories of covalent bonds,including B–O,C=N,C–N,and C=C.Finally,we emphasize the perspectives on basic structure and morphology design,dimension and size design,and conductivity improvement of COFs based on the latest progress in AIBs.We believe that this review provides important guidelines for the development of high-efficiency COF electrode materials and devices for AIBs.

纤维素非溶剂致相分离法制备锂电池隔膜的研究

本研究采用NaOH/尿素/硫脲溶解体系和非溶剂致相分离法制备再生纤维素锂电池隔膜,并比较其与市售聚烯烃Celgard 2400隔膜、纤维素隔膜的电化学性能。结果表明,再生纤维素锂电池隔膜的孔隙率为56.1%、平均孔径为305 nm,电解液吸液率为339%、保液率为68.9%、离子电导率为1.88 mS/cm;在0.5 C倍率下充放电循环100次后,比容量达156.55 mAh/g,库伦效率高于96%。市售Celgard 2400隔膜的离子电导率为0.43 mS/cm,在0.5 C倍率下进行100次充放电循环测试后,其比容量仅为74.26 mAh/g,库伦效率低于88%。与Celgard 2400隔膜相比,再生纤维素锂电池隔膜具有更高的孔隙率、更好的电解质润湿性、更低的内阻、更快的离子传输速度,以及可再生、环境友好等优点,在锂电池领域具有广阔的应用前景。

GB/T 41704—2022国家标准解读

锂离子电池正极材料中磁性异物含量、残余碱含量是供货的必检指标。两项技术指标的测试方法流程长、所含技术要求多,有必要对GB/T 41704—2022的标准方法进行详细解读。本文从标准的结构、主要内容解读锂离子电池正极材料中磁性异物含量、残余碱含量的测试方法,从磁性异物测试的磁选分离条件、磁性异物数量、磁性异物元素溶解及元素浓度测试方法等方面说明标准方法中各步骤的原理和依据;从残余碱含量测试的残余碱提取条件、滴定过程、等当点选取、残余碱含量计算方法等方面说明标准方法中各步骤的原理和依据,为相关测试人员熟悉和应用方法提供参考和借鉴。

阻燃型凝胶聚合物电解质在碱金属电池中的研究进展

阻燃型凝胶聚合物电解质不仅具有良好的枝晶抑制作用,还具有不易泄漏、不可燃等高安全特性,可有效解决热失控或机械冲击等造成的安全隐患,在碱金属电池中具有重要应用前景。该文综述了阻燃型凝胶聚合物电解质在碱金属电池(涉及锂、钠、铝、锌等)中的研究进展。该文首先讨论了凝胶聚合物电解质的阻燃机理;其次,总结了阻燃型凝胶聚合物电解质的常用制备方法;再次,论述了不同类别阻燃型凝胶聚合物电解质在不同碱金属电池体系中的应用状况;最后,提出了目前存在的挑战和未来可能的发展方向。

草酸对NCM622正极浆料性能的影响

为解决中高镍三元材料制浆易凝胶的问题,研究单晶LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)(NCM622)正极材料制浆过程添加草酸对碱含量的影响,制作软包装锂离子电池,测试加工性能和电化学性能。NCM622正极材料加入草酸后,会降低氢氧化锂含量及浆料黏度。进行初始和保存24 h后浆料的对比,发现草酸含量对初始浆料加工性能和电化学性能无明显影响。保存24 h后,未加入草酸的浆料出现凝胶,并导致容量和循环性能异常;加入草酸,可保持浆料正常的加工性能和电化学性能。