Ni-electrolyte (e.g. BaZr0.1Ce0.7Y0.1Yb0.1O3-delta, BZCYYb) cermet are widely used as fuel electrodes in protonic ceramic cells (PCCs) due to their excellent protonic-electronic conductivity, thermal properties, catalytic performance, and cost-effectiveness. However, the high co-sintering (typically >= 1350 degrees C) temperature required to fabricate dense electrolyte onto porous electrodes often leads to microstructure coarsening, incorporation of NiO into the electrolyte, impurity formation, and degrading electrochemical performance, cracking upon reduction, all of which degrade electrochemical performance. This work reveals that the morphology of the initial NiO powder is a critical factor in mitigating these issues. Symmetric cells fabricated with nano-sized NiO (N-NiO) demonstrate significantly lower polarization resistance and superior long-term stability compared to those using combustion NiO (C-NiO). XRD and SEM analyses reveal that NiO, particularly N-NiO, partially incorporates into BZCYYb lattice during sintering and subsequently exsolves as nano-sized Ni particles upon reduction, thereby enhancing fuel oxidation activity. 3D reconstruction further shows that N-NiO-BZCYYb develops longer triplephase boundary (TPB) lengths than C-NiO-BZCYYb, which can be attributed to the improved sintering activity and the uniform particle distribution afforded by the nano-size effect. The extended TPBs not only enhance reaction kinetics but also alleviate interfacial stress between NiO and BZCYYb during reduction, improving microstructural stability. Finally, the elementary steps of the fuel electrode reactions are proposed to provide an in-depth analysis of the electrochemical performance.

Mitigating detrimental chemical crosstalk between the cathode and anode is crucial for improving battery thermal stability and enabling the development of high-energy-density batteries. As the critical interlayer situated between the electrodes, the separator can be strategically designed to regulate the transport of transition metal ions, offering a direct and effective route to suppress chemical crosstalk and enhance battery safety. Herein, we demonstrate a covalent organic framework (COF) functional separator to alleviate this detrimental crosstalk in Li|LiNi0.6Co0.2Mn0.2O2 (NCM622) cells. The COF separator, featuring well-defined nanochannels and abundant functional groups, ensures a uniform Li+ flux and selectively captures dissolved transition metal ions. Moreover, COF cell delivers an initial discharge capacity of 169.3 mAh g-1 with 78% capacity retention after 700 cycles, substantially outperforming the PP-based cell (164.9 mAh g-1, 62%). The COF separator improves performance by suppressing parasitic reactions at both electrodes, promoting a stable SEI on the Li anode, and reducing electrolyte decomposition on the cathode. Furthermore, X-ray photoelectron spectroscopy (XPS) and Density Functional Theory (DFT) calculations confirm that the COF separator effectively inhibits the shuttling and deposition of Ni2+ ions. This work provides a viable strategy to address cathode anode crosstalk in high-energy-density batteries through rational separator design.

Localized high-concentration electrolytes (LHCEs) exhibit excellent interfacial compatibility with lithium metal anodes and high-nickel cathodes, whereas the introduction of polymer networks during gelation may alter their intrinsic solvation structures. Here, we report a solvation-preserving gel electrolyte formed via in situ polymerization of a fluorinated polymer network within a 1,2-Dimethoxyethane (DME)-based LHCE. Unlike conventional gel polymer electrolytes, the fluorinated polymer exhibits limited Li+ coordination, thereby largely preserving the localized high-concentration solvation environment during gelation. This design couples the preserved LHCE solvation chemistry with a fluorinated polymer framework, enabling synergistic regulation of electrode-electrolyte interfaces and enhanced electrochemical performance. Meanwhile, the fluorinated polymer network further improves safety by reducing electrolyte flammability. Lithium symmetric cells achieve stable cycling over 2000 h, while LiNi0.9Co0.05Mn0.05O2 (NCM9)|Li full cells deliver 82.2% capacity retention after 300 cycles and operate stably up to 4.5 V. At the pouch-cell level, a gravimetric energy density of 394.3 Wh kg-1 is achieved under lean-electrolyte conditions, while no thermal runaway is observed up to 300°C. This work demonstrates that preserving solvation structure via rational polymer network design enables simultaneous improvements in interfacial stability, safety, and practical performance in quasi-solid-state lithium metal batteries.

The present work aims to elucidate the effect of Mg17Al12 precipitates on the corrosion behavior and anisotropy in Mg-Al alloys, along with the underlying mechanisms involved. The corrosion of AZ91 is significantly inhibited, and its corrosion anisotropy undergoes substantial changes following aging treatment. These alterations in corrosion behavior can be attributed to the formation of Mg17Al12 precipitates. The precipitates, along with corrosion products, can form a protective barrier layer resembling a "rebar-and-concrete" structure, which significantly inhibits corrosion in AZ91. Furthermore, the corrosion anisotropy of the aged alloy is related to the morphological difference of precipitates on the different orientated surfaces.

The solution-based chemical prelithiation of electrode materials is an effective approach to elevate the initial coulombic efficiency (ICE) and energy-density of the Li-ion battery. Although various lithium-aromatic compound complex solutions (LACSs) have been reported as prelithiation reagents, fundamental understandings are still lacking regarding their drastic difference in prelithiation behavior. In this work, the rate-determining step and some key factors that affect the prelithiation capability were recognized via electrochemical evaluation, spectroscopic analysis, and density functional theory (DFT) calculations. Considering the inherent correlations between the potential of electrochemical Li + -extraction from LACS upon cyclic voltammetry (the oxidation potential of LACS, E O ), the calculated highest occupied molecular orbital (HOMO) energy level, the binding energy (BE) of the solvated Li-ions to the solution (BE solution ), and the prediction accuracy of prelithiation capability and calculations efficiency, we proposed BE-assisted E O as a descriptor for its prelithiation feasibility. This strategy will provide important guidance for the rapid selection and rational design of LACSs for efficient chemical prelithiation.

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AbstractThe global mineral resource development field is facing with common problems such as increasing mining depth, declining resource quality, tightening environmental constraints, and increasing security challenges. The development and utilization technology of mineral resources is in urgent need of innovation. As leading mining countries, starting from the joint research project (JRP) to the establishment of the China–South Africa Joint Research Center for Exploitation and Utilization of Mineral Resources (JRC), China and South Africa have cooperated in depth for over 10 years and made fruitful achievements. The fields of cooperation involve mining, mineral processing, automatic control of mineral processing, comprehensive utilization of tailings, waste catalyst recovery and lithium-ion battery materials. With support of Chinese and South African governments, the two sides jointly held over 10 academic seminars, exchanged more than 20 visiting scientists, introduced 7 South African experts to work in China, and were authorized dozens of patents.

为了在储能技术领域实现高能量密度和良好的安全性目标,全固态锂电池(ASSLBs)成为广泛研究的焦点.作为全固态锂电池的主要组成部分,无机固态电解质在全固态锂电池中起着至关重要的作用.在过去的几年里,无机固态电解质的研究已经取得了重大进展.经过几十年的研究努力,各种具有高离子导电性的锂固体电解质相继报道,硫化物固态电解质在高电位下的不稳定性限制了他在超过4.0 V(vs.Li+/Li)的高压正极材料中的应用;氧化物固态电解质在固固接触上的固有刚性限制了其机械加工性能;卤化物固态电解质同硫化物一并具有严重的空气湿度不稳定性,阻碍其大规模应用.针对电池循环过程中,固态电解质与电极匹配的界面副反应问题、材料本征的吸湿性(空气湿度稳定性差)的问题,以及固态电解质与电极界面物理接触失效问题等技术问题及其改进策略进行了总结和探讨,并提出了关于无机固态电解质自身与界面稳定性未来可行的研究方向.

过滤浓缩机能够增加锂电正极材料前驱体合成过程中反应釜内的固含量,改善前驱体的致密度、球形度.结合其在工业化中的生产情况,对其在锂电正极材料前驱体合成中的应用进行了介绍.

为了提高富锂锰基材料的循环稳定性,以Nb2 O5作为包覆剂,采用高温固相反应法对富锂锰基材料进行包覆改性.研究发现,Nb能够与材料表面的残存锂反应,生成LiNbO3;当Nb包覆量为0.2％ 时样品性能最佳:0.1C下放电比容量为285.6 m A·h/g,1C循环100次后的容量保持率为85.9％,且表现出较好的倍率性能和较低的电压衰减.富锂锰基材料的循环稳定性能的提升可能归因于高温热处理使Nb扩散进入材料表层晶格,形成了较强的Nb—O键,减缓了循环过程中晶格氧的流失,从而稳定结构;同时,表面生成的快离子导体LiNbO3不仅阻止了电解液对材料的侵蚀,而且促进了锂离子的扩散和电子的传导.

层状富锂锰基材料(LMR)凭借其高比容量(>250 mAh/g)和低成本等优点,有望成为新一代锂离子电池用正极材料.从该材料发现至今已有将近30年的时间,却始终没有实现真正商业化应用,主要原因包括:循环过程中,Mn3+迁移进入锂空位,使层状结构向尖晶石结构转变,导致平均放电电压持续降低,造成能量损失严重且给电池管理带来巨大的挑战;Li2MnO3低的电子电导率使LMR材料具有差的倍率性能;较低的电极密度,造成材料的体积能量密度较低;此外,LMR材料需要在高电压下(>4.55 V)才能发挥高容量,但高电压下电解液容易氧化分解,同时伴随着晶格氧被氧化为O2逸出,以上问题严重地影响了其商业化进程.本文基于多年来LMR材料的研究开发成果,综述了近年来LMR材料在充放电机理认识、前驱体工艺路线选择、体相掺杂、表面包覆、液相和气相后处理的作用效果和改性机理,以及O2/O3复合结构、单晶结构等新型特殊结构设计等方面的研究进展,并对LMR材料未来的发展方向和商业化前景进行展望,助力富锂锰基材料的产业化开发.

Current bottlenecks in cobalt (Co) supply have negatively impacted commercial battery application and inspired the development of Co-free cathodes with high energy density. Li-rich layered oxides (LLOs) are promising highenergy cathodes for lithium-ion batteries (LIBs), but the voltage decay and capacity fading are the main challenge for the commercialization. Herein, rich-Co Li1.140Mn0.575Co0.142Ni0.143O2+delta, middle-Co Li1.140Mn0.574Co0.074Ni0.212O2+delta, and Co-free Li1.140Mn0.572Ni0.287O2+delta cathodes were synthesized for investigating the function of Co on the electrochemical performance of LLOs. It is found that Co can promote the oxidation of O2- and contribute more capacity at above 4.5 V, which leads to oxygen release and irreversible structural transformations. As a result, Co-free cathode shows a better cycling stability but lower initial discharge capacity than the two Co-containing cathodes at a cutoff voltage of 4.6 V. Moreover, the Co-free cathode exhibits the highest average discharge voltage of 3.54 V at 0.5C and voltage retention of 95.0% compared with that of middle-Co material (3.47 V and 92.7%) and rich-Co material (3.43 V and 91.6%) after 80 cycles. This study not only provides fundamental insight in the role of Co in LLO cathodes, it also guides us to engineer the high energy and low-cost cathode materials for the rechargeable LIBs in the near future.

采用简单的机械球磨混合法制得NCM@LMFP/C(LiNi0.6Co0.2Mn0.2O2@LiMn0.6Fe0.4PO4/C)复合正极材料,系统地研究了NCM与LMFP/C复合比例(9:1,8:2,7:3,6:4,5:5)对材料电化学性能和热稳定性的影响.使用X射线衍射仪(XRD)、扫描电子显微镜(SEM)和差示扫描量热仪(DSC)对复合正极材料的结构与形貌进行表征研究.研究结果表明:当NCM与LMFP/C复合比例小于8:2时,亚微米级LMFP/C出现富集、团聚,将NCM包埋其中.当NCM与LMFP/C复合比例为8:2时,LMFP/C均匀地包覆在NCM颗粒表面或填充于其颗粒空隙中,材料的电化学性能最优、热稳定性良好:电流为0.1 C和1 C时的放电比容量分别为180.1和165.0 mAh/g,均高于理论测算容量(178.9和164.3 mAh/g);循环80周后容量保持率为95.7％,优于NCM(94.9％);复合正极材料热失控温度相比于NCM提高了25℃且放热量更低.

Ni-rich layered cathode is regarded as one of the most promising candidates to achieve lithium-ion batteries(LIBs) with high energy density. However, due to the irreversible phase transformation(IPT)and its eventual propagation from surface to the bulk of the material, Ni-rich layered cathode typically suffers from severe capacity fading, structure failure, and thermal instability, which greatly hinders its mass adoption. Hence, achieving an in-depth understanding of the IPT propagation mechanism in Ni-rich layered cathode is crucial in addressing these issues. Herein, the triggering factor of IPT propagation in Ni-rich cathode is verified to be the initial surface disordered cation mixing domain covered by a thin rock-salt phase, instead of the rock-salt phase itself. According to the density functional theory(DFT)results, it is further illustrated that the metastable cation mixing domain possesses a lower Ni migration energy barrier, which facilitates the migration of Ni ions towards the Li slab, and thus driving the propagation of IPT from surface to the bulk of the material. This finding clarifies a prevailing debate regarding the surface impurity phases of Ni-rich cathode material and reveals the origin of IPT propagation, which implies the principle and its effectiveness of tuning the surface microstructure to address the structural and thermal instability issue of Ni-rich layered cathode materials.

共沉淀法是工业化中制备多元材料前驱体的主流方法,介绍了沉淀反应、过滤洗涤和烘干三个工序的关键设备,为三元材料前驱体的产业化发展提供参考.

镍钴锰三元材料Li(NixCoyMnz)O2(NCM)作为锂离子电池用正极材料,兼具了较高的可逆容量、优良的热稳定性、低成本等优点,成为笔记本电脑、电动工具、新能源汽车、储能等领域最具前景的锂离子电池正极材料之一.在三元正极材料的结构方面做了介绍,概括了Ni-Co-Mn比例对正极材料热稳定性、放电比容量和容量保持率的影响,并分析了掺杂、包覆与梯度材料的改善作用.最后对三元正极材料的改性、应用及发展前景进行了评价和展望.

锂离子电池在手机、笔记本电脑、新能源汽车和储能等领域发挥着重要作用,正极材料作为锂离子电池的重要组成部分,成为制约其大规模推广应用的关键.镍钴锰酸锂具有比容量高、成本较低、稳定性能好等优势,是最具前景的锂电池正极材料之一.本文调研了近年来的相关文献,着重介绍不同三元材料的制备方法以及锂离子电池改性策略.最后指出镍钴锰酸锂三元正极材料目前遇到的最大问题以及未来发展方向.

永磁除铁器具有磁力强、结构简单、能耗小、操作简便、使用成本低等特点,本文主要介绍了不同种类型的永磁除铁器及其在多元材料前驱体中的应用,通过在多元材料前驱体制备过程中全流程使用永磁除铁器,可以有效低降低多元材料前驱体的磁性异物.

共沉淀法制备多元材料前驱体的合成工艺主要有连续式和间歇式两种.本文结合实际应用情况对这两种合成工艺进行介绍,为多元材料前驱体的制备提供参考.

基于固态电解质的锂电池具有高能量密度和高安全的优势,是下一代储能系统的重要发展方向.然而单一固态电解质存在离子电导率低、界面阻抗大等问题.无机有机复合固态电解质结合了氧化物和聚合物材料的优势被认为是最有潜力的体系.本文综述了无机有机复合固态电解质的研究进展,包括电解质的设计制备以及界面行为的改善,并展望了固态电池的发展.