A comprehensive understanding of interactions between cathode, electrolyte, anode, and packaging during battery operation is crucial for advancing performances but remains overlooked due to the lack of characterisation technics capable of measuring these components simultaneously. We perform a holistic investigation of a compact all-solid-state-battery using operando synchrotron X-ray micro-diffraction imaging. We image in real time and simultaneously the lattice parameter and crystal orientation of the dense LiCoO2 cathode, the Ti current collector and the electrodeposited Li metal anode. We reveal that reaction mechanism of LiCoO2 depends on the crystal orientation, and that, in dense electrodes as opposed to porous ones, the delithiation is limited by the formation of a Li-rich insulating interface. Li metal crystal orientation is found to be influenced initially by the Ti texture and to change within minutes during plating and stripping. These results demonstrate the power of X-ray imaging to link reaction mechanism and grain orientation during non-equilibrium processes.
The intriguing mechanism of phosphorus anodes for sodium ion batteries revealed by operando pair distribution function and X-ray diffraction computed tomography
Unraveling the storage mechanism of Na$_{3}$V$_{2-x}$Ni$_x$(PO$_4$)$_2$F$_3$/C cathodes for sodium-ion batteries through electrochemical, {\it operando} X-ray diffraction and microscopy studies
本研究结合 EIS、GITT、CV、operando XRD 与原位同步辐射 TXM,揭示 Ni 掺杂 Na₃V₂(PO₄)₂F₃/C 正极的储钠机制、扩散动力学及长循环稳定性。
Operando probing of Li-insertion into LiMn$_2$O$_4$ cathodes by spectroscopic ellipsometry
提出了一种基于椭圆偏振光谱技术(SE)的电池电极离子嵌入和荷电状态的非破坏性观测方法。这种技术的潜力,用于执行时间分辨测量的(脱)锂过程的电极材料已被证明使用薄膜尖晶石LiMn $_2$ O $_4$作为锂离子电池的阴极。Li+离子在该材料中的化学扩散率已经由Li插入到膜中的时间演变确定,并且根据这些结果,已经可以将在该材料中观察到的有争议的赝电容行为与该层的纳米结构相关联。这里提出的结果建立了一个新的方法,电池材料和设备的operando表征提供了一个强大的工具,在电化学设备的集合中的离子扩散机制的理解。
Spatially inhomogeneous delithiation in LiNiO2 positive electrode: the effect of X-rays dose
Synchrotron SOLEIL(Soleil 同步辐射光源);Technische Universität München(慕尼黑工业大学);Centre National de la Recherche Scientifique, CNRS UR1(法国国家科学研究中心);Réseau sur le Stockage Electrochimique de l’Energie (RS2E), CNRS FR3459(电化学储能研究网络);Sorbonne Université, CNRS, Physicochimie des Electrolytes et Nanosystèmes Interfaciaux, CNRS UMR8234(索邦大学)
Pseudo-ternary LiBH4-LiCl-P2S5 system as structurally disordered bulk electrolyte for all-solid-state lithium batteries
研究了LiBH_4-LiCl-P_2S_5混合体系在全固态电池中的性能。所研究的材料在加热到601 ℃以上时发生非晶化,伴随着有利于电池电解质应用的Li+电导率增加。在室温下测得的离子电导率为10- 3Scm-1,非晶化后的激活能为0.40(2)eV。材料的结构分析和表征表明,BH 4基团和PS 4可能属于相同的分子结构,其中Cl离子相互作用以容纳结构单元。由于其导电性,延展性和电化学稳定性(高达5 V,Au vs. Li+/Li),这种新的电解质在使用阴极材料(层状TiS 2,theo.在501 ℃下,以Li为阳极,在12 mA g ~(-1)(0. 05 C-倍率)的电流密度下进行10次循环,容量保持率为93%,循环稳定性良好。通过透射模式的同步加速器X射线衍射进行的进一步先进表征明显有助于更好地了解在中等温度下运行的固态电池电极的(脱)锂过程。
Operando study of the evolution of peritectic structures in metal solidification by quasi-simultaneous synchrotron X-ray diffraction and tomography
University of Hull(赫尔大学);Westlake University(西湖大学);Diamond Light Source Ltd.(钻石光源有限公司);Research Complex at Harwell(哈韦尔研究综合体);Kunming University of Science and Technology(昆明理工大学)
Operando monitoring of single-particle kinetic state-of-charge heterogeneities and cracking in high-rate Li-ion anodes
近年来,对能够存储更多能量、更快充电和更长使用寿命的电池技术的需求迅速上升,这主要是由交通运输电气化和电网规模储能系统的推动。这导致了许多有前途的新型高倍率锂离子电池电极材料的开发。为了合理化和改善材料性能,至关重要的是要了解在实际电池运行过程中发生的纳米到中尺度的基本离子嵌入和降解机制。在这里,我们应用一个简单的实验室为基础的operando光学散射显微镜的方法来研究微米级棒的高速率阳极材料Nb $_{14}$ W $_3$ O $_{44}$在循环过程中的速率高达30 C。我们直接可视化杆的伸长,通过与系综X射线衍射的比较,使我们能够确定单个粒子的荷电状态(SOC)。还观察到散射强度随SOC的连续变化,使得能够观察到单个颗粒内的非平衡动力学相分离。相场建模(由脉冲场梯度核磁共振和电化学实验提供信息)被用来验证这种分离的动力学起源,其起因于锂离子扩散系数对SOC的依赖性。最后,我们见证了这种颗粒内SOC异质性如何导致颗粒开裂;我们跟踪所得碎片的循环行为,并表明它们可能与电极电断开。这些结果表明,光学散射显微镜的权力,以跟踪快速的非平衡过程,往往发生在不到1分钟,这将是不可访问的既定表征技术。
In Situ Nanometer-Resolution Strain and Orientation Mapping for Gas-Solid Reactions via Precession-Assisted Four-dimensional Scanning Transmission Electron Microscopy