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1. Current-Dependent Morphologies of Insulating Electrodeposits in Li–O ₂ Batteries Controlled by Coupled Ion-Electron Transfer Kinetics

   https://doi.org/10.1021/acsami.5c03369  

   Zhang, Penghao; Pathak, Shakul; Bazant, Martin Z; Bai, Peng (June 2025, ACS Applied Materials & Interfaces)

   To address the dynamic heterogeneities in porous carbon electrode used in Li-O2 batteries, microscopic charge transfer theory offers much better explanations and predictions for the reactive nucleation and growth dynamics of oxide formation during discharging a Li-O2 battery. 

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2. Stable metal anodes enabled by a labile organic molecule bonded to a reduced graphene oxide aerogel

   https://doi.org/10.1073/pnas.2001837117  

   Gao, Yue; Wang, Daiwei; Shin, Yun Kyung; Yan, Zhifei; Han, Zhuo; Wang, Ke; Hossain, Md Jamil; Shen, Shuling; AlZahrani, Atif; van Duin, Adri C. T.; et al (November 2020, Proceedings of the National Academy of Sciences)

   Metallic anodes (lithium, sodium, and zinc) are attractive for rechargeable battery technologies but are plagued by an unfavorable metal–electrolyte interface that leads to nonuniform metal deposition and an unstable solid–electrolyte interphase (SEI). Here we report the use of electrochemically labile molecules to regulate the electrochemical interface and guide even lithium deposition and a stable SEI. The molecule, benzenesulfonyl fluoride, was bonded to the surface of a reduced graphene oxide aerogel. During metal deposition, this labile molecule not only generates a metal-coordinating benzenesulfonate anion that guides homogeneous metal deposition but also contributes lithium fluoride to the SEI to improve Li surface passivation. Consequently, high-efficiency lithium deposition with a low nucleation overpotential was achieved at a high current density of 6.0 mA cm⁻². A Li|LiCoO₂cell had a capacity retention of 85.3% after 400 cycles, and the cell also tolerated low-temperature (−10 °C) operation without additional capacity fading. This strategy was applied to sodium and zinc anodes as well. 

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3. The effect of local lithium surface chemistry and topography on solid electrolyte interphase composition and dendrite nucleation

   https://doi.org/10.1039/C9TA03371H  

   Meyerson, Melissa L.; Sheavly, Jonathan K.; Dolocan, Andrei; Griffin, Monroe P.; Pandit, Anish H.; Rodriguez, Rodrigo; Stephens, Ryan M.; Vanden Bout, David A.; Heller, Adam; Mullins, C. Buddie (June 2019, Journal of Materials Chemistry A)

   With more than 10 times the capacity of the graphite used in current commercial batteries, lithium metal is ideal for a high-capacity battery anode; however, lithium metal electrodes suffer from safety and efficiency problems that prevent their wide industrial adoption. Their intrinsic high reactivity towards most liquid organic electrolytes leads to lithium loss and dendrite growth, which result in poor efficiency and short circuiting. However, the multitude of factors that contribute to dendrite formation make determining a nucleation mechanism extremely difficult. Here, we study the intricate science of dendrite nucleation on metallic lithium by using an array of analytical techniques that provide simultaneous ultra-high spatial sensitivity and chemical selectivity. Our results reveal a 3D picture of the chemical make-up of the native Li surface and the resulting solid electrolyte interphase (SEI) with better than 200 nm resolution. We find that, contrary to the general understanding, the initial surface chemistry, not the topography, is the dominant factor leading to dendrite nucleation. Specifically, inhomogeneously distributed organic material in the native surface leads to inhomogeneously dispersed LiF-rich SEI regions where dendrite nucleation is favored. This has significant implications for battery research as it elucidates a mechanism for inhomogeneous SEI formation, something that is accepted, but not well understood, and highlights the importance of Li surface preparation for experimental studies, which is implicit in battery research, but not directly addressed in the literature. By homogenizing the initial lithium surface composition, and thus the SEI composition, we increase the number of dendrite nucleation sites and thereby decrease the dendrite size, which significantly increases the electrode lifetime. 

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4. Operando real-space imaging of a structural phase transformation in the high-voltage electrode LixNi0.5Mn1.5O4

   https://doi.org/10.1038/s41467-024-55010-6  

   Sun, Yifei; Hy, Sunny; Hua, Nelson; Wingert, James; Harder, Ross; Meng, Ying Shirley; Shpyrko, Oleg; Singer, Andrej (December 2024, Nature Communications)

   Abstract Discontinuous solid-solid phase transformations play a pivotal role in determining the properties of rechargeable battery electrodes. By leveraging operando Bragg Coherent Diffractive Imaging (BCDI), we investigate the discontinuous phase transformation in Li_xNi_0.5Mn_1.5O₄within an operational Li metal coin cell. Throughout Li-intercalation, we directly observe the nucleation and growth of the Li-rich phase within the initially charged Li-poor phase in a 500 nm particle. Supported by the microelasticity model, the operando imaging unveils an evolution from a curved coherent to a planar semi-coherent interface driven by dislocation dynamics. Our data indicates negligible kinetic limitations from interface propagation impacting the transformation kinetics, even at a discharge rate of C/2 (80 mA/g). This study highlights BCDI’s capability to decode complex operando diffraction data, offering exciting opportunities to study nanoscale phase transformations with various stimuli. 

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5. Nucleation Behavior of Pitting and Evolution of Stripping on Lithium Metal Batteries

   https://doi.org/10.1149/MA2024-0271004mtgabs  

   Zhang, Hanrui; Ulusel, Mert; Shi, Feifei (November 2024, ECS Meeting Abstracts)

   The stripping reaction of lithium will greatly impact the cyclability and safety of Li metal batteries. However, lithium pits' nucleation and growth, the origin of uneven stripping, are still poorly understood. In this study, we analyze the nucleation mechanism of Li pits and their morphology evolution with a large population and electrode area (>0.45 cm²). We elucidate the dependence of pit size and density on current density and overpotential, which is aligned with classical nucleation theory. With laser scanning confocal microscope, we reveal the preferential stripping on certain crystal grains and a new stripping mode between pure pitting and stripping without pitting. Descriptors like circularity and the aspect ratio (R) of pit radius to depth are used to quantify the evolution of lithium pits in three dimensions. As pits grow, growth predominates along the through-plane direction, surpassing the expanding rate at the in-plane direction. After analyzing more than 1000 pits at each condition, we validate that the overpotential is inversely related to the pit radius and exponentially related to the rate of nucleation. With this established nucleation-overpotential relationship, we can better understand and predict the evolution of surface area and roughness of lithium electrodes under different stripping conditions. The knowledge and methodology developed in this work will significantly benefit lithium metal batteries' charging/discharging profile design and the assessment of large-scale lithium metal foils. DOI of publication: 10.1021/acsami.4c01530 Acknowledgments: H.Z., M.U., and F.S. thank the support from the Assistant Secretary for Energy Efficiency and Renewable Energy, Office of Vehicle Technologies of the US Department of Energy through the Advanced Battery Materials Research Program. F.S. thanks the support from the National Science Foundation under Grant No. 2239690. 

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