bluuebunny/crossref_metadata_2025_split huggingface dataset:
Case Dependent Metal Dissolution in Li/NMC Batteries
Authors: Merrill Laura C , Gruenwald Hannah Kay , McBrayer Josefine , Fritzsching Keith J. 
Published: December 2024

Though active materials (electrolyte, electrodes) drive the performance of batteries, the non-active materials (current collector, case material) and cell format (e.g., pouch cell, coin cell) can also influence battery performance. Many next-generation battery systems implement high theoretical capacity electrodes with wide operating voltages to enable high energy density batteries. To achieve this, Li metal anodes are often paired with high voltage, Ni-rich LiNixMnyCo1-x-yO2 (x ≥ 0.6, “NMC”) cathodes. Many focus on the development of electrolyte formulations that can effectively cycle Li metal with high Coulombic efficiency while maintaining electrochemical stability at the cathode material. These electrolytes are typically based on high, or localized-high, concentrations of lithium bis(fluorosulfonylimide) (LiFSI). Electrolytes based on LiFSI are suspected to be incompatible with both Al current collectors and stainless steel cathode caps, and typically the stainless steel cathode cap is coated with Al to mitigate corrosion.
Here we explore the effect of inactive cell components on Li/NMC battery performance. We investigate mechanistic pathways of case and current collector metal dissolution and the influence of the inactive cell components on NMC transition metal dissolution in both high and localized high concentration electrolytes. We combine electrochemical experiments with ex-situ nuclear magnetic resonance spectroscopy and X-ray fluorescence experiments to track the metal dissolution within the electrolyte with cycling. We also explore the prevalence of galvanic corrosion when two dissimilar metals are in electrical contact with each other (e.g., Al current collector and the steel coin cell case) in each electrolyte. We find that the localized high concentration electrolyte has greater amounts of metal dissolution when cycled in stainless steel compared to the diluent-free high concentration electrolyte, suggesting the addition of the diluent solvents drives the material incompatibility with typical stainless steel coin cell parts.
SNL is managed and operated by NTESS under DOE NNSA contract DE-NA0003525
Ion Transport Enhancement Mechanism in Polymer/Ceramic Composite Electrolyte with High-Entropy Li-Garnet
Authors: Ock Jiyoung , Lehmann Michelle , Fu Zhezhen , Wang Yangyang , Bhattacharya Amit , Wang Tao , Dai Sheng , Clement Raphaele J , Sokolov Alexei P. , Chen Xi Chelsea 
Published: December 2024

Given the growing demand for electrification, delivering safe, high power, and high energy in lithium-ion batteries is a key challenge. One possible approach is incorporating Li-ion conductive ceramics into a polymer electrolyte matrix. Benefiting from both components, composite electrolytes may deliver high safety, improved ionic conductivity, enhanced electrochemical stability, and feasible construction for solid-state batteries. Specifically, it is crucial to understand and verify the ion transport enhancement mechanism in such a composite electrolyte, as the conductivity in the electrolytes directly affects the overall cell performance and the electrolyte design principles for these systems may change.
In this work, we investigate the ion transport enhancement mechanism in composites made with a single-ion conducting (SIC) polymer electrolyte with high-entropy Li-garnet (HE-LLZO) micron-sized powders. We use broadband dielectric spectroscopy (BDS), thermal gravimetric analysis (TGA), rheology measurement and proton nuclear magnetic resonance (1H NMR) to understand the ion transport kinetics in the composites. At 30 °C, 30 wt% HE-LLZO composites with SIC polymer showed almost 8-fold enhancement in conductivity. The addition of HE-LLZO leads to the different degree of polymerization compared to that of the pure polymer, implying that the substantial amount of unpolymerized monomer facilitated the conductivity in the composites. To further investigate the reaction mechanism in the composites, Fourier transform infrared (FT-IR) spectroscopy results will be presented along with 1H NMR data. Electrochemical properties and cell performance will be compared to further illustrate the effects of HE-LLZO on the composite.

Acknowledgements

This work was supported as part of the Fast and Cooperative Ion Transport in Polymer-Based Materials (FaCT), an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences at Oak Ridge National Laboratory under contract DE-AC05-00OR22725.
Interfacial and Electrolyte Solution Reactions at Nickel-Rich Electrodes
Authors: Jones Kieran , Denison Benjamin , McNulty Rory , Walsh Darren Anthony , Newton Graham , Johnson Lee R 
Published: December 2024

The demand for secondary batteries has rapidly grown, driven by the societal transition to electric and hybrid modes of transportation, with the lithium-ion battery finding extensive application throughout the energy storage industry. To attain the energy density required to meet the needs of society, research efforts have shifted to pushing the voltage limits of the cell and the use of high nickel contents, for example, LiNi0.8Mn0.1Co0.1O2 (NMC811) and LiNiO2. These nickel-rich layered metal oxides offer increased capacity, and also limit or entirely remove the need for expensive and unsustainable cobalt in the cell. Despite their promise, these nickel-rich electrodes are known to decompose at high voltages, 4.2 V-4.5 V depending on nickel content, with nickel’s oxidation state changing from +4 to +2, forming a rock salt-like structure, and evolving oxygen. The redox and structural changes occurring in the bulk materials are well documented, but the interfacial and electrolyte solution reactions are less well understood.
Here we consider how the surface chemistry of the nickel-rich electrodes changes during cycling and how this may impact degradation at the surface. Specifically, we track the formation and decomposition of surface products quantitatively. These events are compared to the potentials at which oxygen is released from the cell, monitored using online electrochemical mass spectrometry, to unravel degradation reactions of the electrolyte solutions. We have combined a range of methods including nuclear magnetic resonance spectroscopy, gas chromatography–mass spectrometry, and fluorimetry to understand electrolyte degradation at NMC811 electrodes and have been successful in identifying vinylene carbonate in extracted electrolyte, among other components. These data confirm previous reports that NMC811 is able to form vinylene carbonate in situ. Vinylene carbonate is added to lithium-ion cells to stabilise the graphite negative electrode, including in next generation nickel-rich cells, but due to its formation within NMC811 cells, we show its addition is not required. Finally, we consider how vinylene carbonate forms within the cell and unpick the reactive species responsible for its production. In particular, singlet oxygen has been proposed to be released from the NM811 electrodes into the electrolyte solution where it can act as an oxidant. This reaction has been explored using photocatalysts and here we consider the validity of this approach and the reaction of singlet oxygen with the electrolyte solution.
New Hybrid Nano-Architecture of Sulfur Electrode for Lithium-Sulfur Batteries
Authors: Ezzedine Mariam , Jardali Fatme , Florea Ileana , Sorin Costel 
Published: December 2024

Lithium-Sulfur batteries have the potential to provide a much greater energy storage capacity than current Lithium-ion batteries. However, Lithium-Sulfur batteries are hampered by challenges arising from the cell level, such as poor conductivity of sulfur, its volume expansion, and the lithium polysulfides shuttle effect. The technology developed in our lab overcomes these fundamental challenges by implementing an innovative electrode architecture that exploits the properties of vertically aligned carbon nanotubes (VACNTs). The hierarchical-assembled-nanostructured battery positive electrode is based on carbon nanotube carpets grafted by 100% sulfur nanomaterial. Coupling it with metallic lithium as negative electrode results in high energy and power, and long-life Lithium-Sulfur battery (Figure 1). The positive electrode topology enables to store more electrical charge more rapidly than any other commercial electrode, positively impacting the power and energy storage capacity of the battery. The Lithium-Sulfur batteries exclude inactive components (such as binders/additives essential for traditional Lithium-ion batteries), thus eliminating the “dead weight” found in the today’s batteries.
Electrochemical performance tests have shown that the Lithium-Sulfur batteries developed in our work have substantially improved capacity performance, stability and cycle life compared to conventional Lithium-Sulfur batteries. At a discharging rate of 2C (i.e., 30 minutes), the cells have shown a stable specific capacity of 400 mAh g-1 over 1000 cycles.
(ECS Charles W. Tobias Young Investigator Award Address) Lithium Oxide Content in the Li Metal Anode Solid Electrolyte Interphase Drives High Coulombic Efficiency
Authors: Gallant Betar M. 
Published: December 2024

Despite remarkable improvements in Li cycling Coulombic efficiency (CE) in recent years, Li anodes still cannot meet the >99.9% CE needed for >1,000 cycle life. This shortfall arises from uncontrolled reactivity at the solid electrolyte interphase (SEI) and its resulting properties, leading to inhomogeneous plating and stripping, continuous electrolyte consumption, and loss of active Li inventory. Despite progress in electrolyte design, the lack of precise SEI understanding hinders attempts to rationally design an improved interface towards bridging remaining gaps in CE.
Recent advancement in quantitative chemical analysis of cycled Li anodes has enabled unprecedented understanding of the origin of capacity loss. Pioneering work by Meng et al. demonstrated the method of titration gas chromatography (TGC) for quantifying the amount of metallic Li0 which becomes entrapped in the electrode residuals over repeated cycling.1 The authors showed that Li0 is mainly responsible for capacity loss at intermediate values of CE, and decreasing Li0 is therefore effective for improving performance. As CE becomes very high, however, losses become dominated by the SEI formation itself.2

This talk will describe our efforts to build upon and advance chemical titration by coupling to gas chromatography (GC) and other liquid-phase assays, which has enabled tracking of an extended array of key SEI phases and their proportions over cycling. Beyond Li0, such methods enable accurate resolution of capacity loss as stranded phases to semicarbonates (ROCO2Li), lithium carbide (Li2C2), olefins (RLi), LiF, and P-containing phases, as well as total Li loss, which allow for compositional trends with CE to be revealed. In a prior work,3 we achieved chemical resolution of up to ~70% of the total capacity loss and ~33% of SEI phases, yet still with significant unknown phase contributions. Recently, we have further advanced these titration techniques to quantify an additional key SEI phase, lithium oxide (Li2O),4 which substantially improves upon these numbers. Statistical analysis of correlations between major ionic and organic phases and CE unambiguously reveal that Li2O content is the most strongly predictive of high CE, even moreso than LiF content—widely asserted to be a uniquely beneficial SEI component—or decreasing Li0. By designing several new O-rich and low-F or F-free electrolytes that achieve highly competitive CE breaching 99%, we reveal a compelling electrolyte design landscape based on oxygenation, rather than fluorination.

Fang, J. Li, M. Zhang et al., Nature 2019,572, 511–515.

M. Hobold, J. Lopez, R. Guo, et al., Nature Energy 2021, 6, 951-960.

M. Hobold and B. M. Gallant, ACS Energy Letters 2022, 7, 3458-3466.

M. Hobold, C. Wang, K. Steinberg et al., Nature Energy 2024 (published ASAP).
Highly Li-Concentrated Ionic Liquid Electrolytes Enable High Stability of LiNiO2
Authors: LIU Huazhen , Maeda Hiroki , Hwang Jinkwang , Matsumoto Kazuhiko 
Published: December 2024

Since the commercialization of lithium-ion batteries (LIBs) in 1991, LIBs have widely served as a power supply, from consumer electronics and electric vehicles to large-scale energy storage systems. The surge in energy markets, especially the expanding demand for electric vehicles, highlights the urgent need for LIB technologies that provide high energy density, durability, and cost-effectiveness. This drives the expectations of cobalt-free LiNiO2 as positive electrode, which possesses a low cost and an impressively high theoretical energy density (1050 Wh kg−1) for future use.1
However, the commercial application of LiNiO2 is blocked by ongoing issues such as Ni dissolution, structural disordering, and particle cracking, resulting in a low reversible specific capacity, low cyclability, and safety risk.2 Moreover, the use of LiPF6-containing carbonate-based electrolytes makes Ni dissolution drastic due to the attack by HF, which is produced by hydrolysis of LiPF6.3 Exploring electrolytes containing chemically stable salts, such as Li[FSA] ([FSA]− = bis(fluorosulfonyl)amide), becomes an attractive option to enhance cycling stability and mitigate parasitic reactions.
In this study, Li[FSA]-based ionic liquids (ILs) electrolytes including two different cations ([C2C1im]+ = 1-ethyl-3-methylimidazolium, [C3C1pyrr]+ = N-methyl-N-propylpyrrolidinium) are investigated for their performance toward LiNiO2 cathode. 1 mol dm−3 LiPF6-EC/DMC (1:1 v/v) is chosen as the baseline electrolyte. All the IL electrolytes exhibit enhanced cycle performance than the baseline electrolyte, especially highly concentrated [C3C1pyrr]-based electrolytes, reaching a capacity retention of 73.1% after 500 cycles. The surface morphology and chemical characterization reveal the stable cathode electrolyte interphase formed on the LiNiO2 cathode, which is capable of suppressing Ni dissolution and alleviating capacity fade. Moreover, Al corrosion behavior is examined in different electrolytes, which reveals the Al current collector corrosion is mitigated in the highly concentrated [C3C1pyrr]-based electrolyte.

References

[1] T. Deng, X. Fan, L. Cao, J. Chen, S. Hou, X. Ji, L. Chen, S. Li, X. Zhou, E. Hu, D. Su, X. Yang and C. Wang, Joule, 2019, 3, 2550-2564.
[2] E. Quisbert, F. Fauth, A. Abakumov, M. Blangero, M. Guignard, and C. Delmas, Small, 2023, 19, 2300616.
[3] R. Pan, E. Jo, Z. Cui, and A. Manthiram, Adv. Funct. Mater., 2023, 33, 2211461.
Chemical Prelithiation of Silicon Oxide Anodes for Improved Performance in Lithium-Ion Batteries
Authors: Bonneux Gilles , Feng Kun , Moeremans Boaz , D'Haen Jan , Ruttens Bart , Safari Momo , Van Bael Marlies K. 
Published: December 2024

Si/SiOX-based materials possess significant potential as an anode in Li-ion batteries, due to their high capacity, stable cycling performance and the volume expansion buffering of the SiOX matrix upon lithiation of silicon nanodomains. However, one of the main challenges is their low initial coulombic efficiency (ICE), due to SEI formation and irreversible parasitic reactions which trap Li ions inside the electrode matrix or at the interface. Prelithiation aims to compensate for the large initial irreversible capacity losses, which can be achieved by introducing active lithium directly into the anode material before cycling.
Through chemical prelithiation, the electrode coating or active material powder is brought in contact with a reactive Li-containing precursor solution via immersion, which allows a direct reaction at the surface. The precursor system ideally requires a sufficiently low redox potential to achieve (partial) prelithiation of the SiOX matrix, while minimizing full Si lithiation and Li plating at the electrode surface. Lithium-Arene complexes dissolved in (cyclic) ether solvents have been shown to have adequate reducing strength (0.2-0.3V vs. Li/Li+) to allow these redox reactions.
In this study, the effects of chemical prelithiation on the battery performance are evaluated inside a half-cell, mainly focusing on the initial cycles. Additionally, the effect of prelithiation on the morphology and composition of the electrode (active) material will be investigated using electron microscopy (SEM) and X-ray diffraction (XRD), including the effect of air exposure on the phase stability. Furthermore, the chemical state of the sample surface is studied, giving deeper insights into its interfacial reactivity and composition. Ultimately, this study aims to create a better understanding of the advantages and disadvantages of this prelithiation method on Si/SiOX-based anodes, paving the way for the development of more efficient lithium-ion batteries.
Electrochemical Reactions of Graphite Fluoride Electrodes in Ionic Liquids
Authors: Ito Yuta , Yoshii Kazuki , Takeuchi Tomonari , Okumura Toyoki 
Published: December 2024

Li-graphite fluoride (CF
x
) primary batteries show the highest energy density (2180 Wh kg−
1) among commercialized Li primary batteries, long life storage, and wide operating temperature range, and are the power sources for medical equipment, stand-alone devices, remote keyless systems, and space crafts. Recently, Li-CF
x
cells could be used as secondary batteries1 and are attracting attention as next-generation storage batteries with high energy density. Current problems of conventional Li-CF
x
batteries are safety issues due to using flammable organic electrolytes and short cycle life originated from oxidative decomposition of organic solvents while using as secondary batteries. In this study, we focused on the application of ionic liquids which shows nonvolatile, nonflammable, and wide electrochemical potential window. However, there had been no previous reports of Li-CF
x
battery operation using ionic liquids.
In Li-CF
x
primary batteries with organic electrolytes, solvent and Li+ co-intercalate into CF
x
layer to form an intermediate product and that decomposes to LiF and amorphous carbon (intermediate mechanism).2 Because of the strong interaction between organic solvent and Li+, the solvated Li+ can diffuse into the bulk of the CF
x
. The slow desolvation within the CF
x
layer contributes to the small and dispersed crystallization of LiF, and CF
x
can react completely.3 In the case of ionic liquids, however, Li+ and CF
x
may react directly due to the lack of solvent, resulting in localized crystallization of LiF, inhibiting subsequent Li+ intercalation and preventing CF from reacting completely.
Therefore, in this study, we focused on shortening the diffusion distance of Li+ and made the CF
x
particles finer to submicron size and the electrochemical reaction of CF
x
with Li+ ions were successfully carried out completely in ionic liquids. In this presentation, we will report the fundamentals on the electrochemical reactions of CF
x
electrodes in ionic liquids, including how the components of ionic liquids influence on the electrode potential of CF
x
. The realization of Li-CF
x
batteries using ionic liquids will expand the range of applications with batteries at the environments (undersea, subterranean, and outer space) where conventional batteries have been difficult to be used.

Y. Ito, et al., Chem. Mater., 34, 19, 8711, (2022).

H. Touhara, et al., Solid State Ionics, 14, 163 (1984).

J. Wang, J. Mater. Chem. A, 8, 6105 (2020).
Three-Dimensional Imaging of Large-Volume Lithium Metal Microstructure by Xenon Plasma Focused Ion Beam
Authors: Peng Yueying , Nishikawa Kei , Kanamura Kiyoshi 
Published: December 2024

Advanced energy storage systems are increasingly in demand due to the rising needs of portable electronics, electric vehicles, and grid-scale energy storage. Lithium (Li) metal stands out as an exceptional battery anode with its high theoretical specific capacity (3860 mA g-1 compared to graphite's 372 mA g-1) and low redox potential (-3.04 V vs. the standard hydrogen electrode). However, practical Li metal anodes often face challenges such as low Coulombic efficiency, short cycle life, and safety concerns, mainly due to the reactive nature of Li metal and the unpredictable deposition with diverse morphologies.
Developing advanced Li metal anodes requires a deep understanding of their electrode structure. It is indispensable to find three-dimensional (3D) images. However, obtaining accurate 3D imaging of Li anodes poses significant challenges. On one hand, the non-uniform electrodeposition of Li metal necessitates a large sample to accurately represent the entire electrode. On the other hand, achieving high resolution is essential for distinguishing the complex phases within the Li electrode, including metallic Li, solid electrolyte interphase (SEI), and pores. While popular 3D imaging technologies like X-ray computed tomography and nuclear magnetic resonance imaging offer comprehensive size information, they often struggle with limitations in resolution or imaging contrast. Traditional focused ion beam-scanning electron microscopy (FIB/SEM) can provide high-resolution images at nanoscale, but its use of gallium ion (Ga+) leads to issues such as ion implantation and limited size (≤ 10 μm). An emerging alternative, plasma FIB/SEM (PFIB/SEM), coupled with Xenon (Xe) gas, featured by both high resolution and large volume size, presents a promising solution, making it appealing for characterization of Li electrode.
In this presentation, Xe PFIB is employed for 3D imaging of electrodeposited Li with a large volume (200 μm in dimension) and high resolution (50 nm per pixel). This approach facilitates the clear identification of two phases: deposited Li metal and SEI/pores. It enables the quantification of their spatial distribution, packing density, and specific surface area, crucial parameters determining the Coulombic efficiency of the deposited Li anode. Furthermore, the ability to separate individual Li particles provides quantitative information on volume size, particle number, and shape. These quantitative results establish a robust mathematical relationship with the overpotential of Li deposition, significantly enhancing our understanding of the Li electrodeposition process.
Leveraging the large volume and high-resolution 3D information obtained through Xe PFIB-SEM, this work demonstrates its significance in assessing and understanding electrodeposited Li, offering valuable insights for designing advanced Li metal anodes. Xe PFIB-SEM methodology is poised to become a pivotal technique for 3D characterization in energy storage materials and related fields.