bluuebunny/crossref_metadata_2025_split huggingface dataset:
(Battery Division Research Award) A New Perspective on Layered Transition Metal Oxides As Cathode Active Materials
Authors: Liaw Boryann (Bor Yann) , Li Meng 
Published: November 2022

High energy rechargeable lithium batteries (RLBs) continue to be the most favorite choice for vehicle electrification [1]. Among all cathode active materials, layered transition metal oxides containing nickel (Ni), manganese (Mn), or cobalt (Co), remain the most desired to improve energy density and performance [2]. As the current electrolyte system restricts high voltage operation, new cathode active materials with higher capacity are being sought today. How to seek a better cathode active material needs some better guidance as well. Here, a new perspective on the layered transition metal oxide cathode active materials is proposed based on our recent analysis of the performance characteristics of these current cathode active materials that were evaluated or reported in the literature. This new perspective is supposed to provide a more coherent framework to explain their commonality of the performance in realizing higher capacity within the same stability range. With this perspective, the principle of seeking a better cathode active material could be improved with this understanding.
References:

Bao, Y. Cui, E. Dufek, J. Goodenough, P. Khalifah, Q. Li, B.Y. Liaw, A. Manthiram, Y.S. Meng, et al. “Pathways for practical high-energy long-cycling lithium metal batteries.” Nat. Energy 4 (2019) 180–186. https://doi.org/10.1038/s41560-019-0338-x.

A. Manthiram. Reflection on lithium-ion battery cathode chemistry. Nat. Commun. 11 (2020) 1550. https://doi.org/10.1038/s41467-020-15355-0.
(Si)GeSn Isothermal Multilayer Growth for Specific Applications Using GeH4 and Ge2H6
Authors: Concepción Díaz Omar , Søgaard Nicolaj Brink , Krause Oliver , Bae Jin Hee , Brazda Thorsten , Tiedemann Andreas T. , Zhao Qing-Tai , Grützmacher Detlev , Buca Dan 
Published: November 2022

The experimental demonstration of Ge1-xSnx alloys lasers opened group-IV materials towards high-performance electronic and photonic devices that can be easily integrated with the current Si semiconductor technology. In recent years, GeSn-based optoelectronic devices including light-emitting and detectors, modulators, and CMOS have been proven.
The major challenges for the Ge1-xSnx epitaxy arise from the low solid solubility of Sn in Ge, the large lattice mismatch, and the reduced thermal stability between Ge and Sn. All these are becoming extremely critical at higher Sn contents. Non-equilibrium conditions offered by molecular beam epitaxy (MBE), chemical vapor deposition (CVD), flash lamp, or laser annealing have been lately investigated. Between them, CVD is to date the preferred growth technique for its current development compatible with the industry offering micron-thick layers with the highest crystal quality.
While Tin-tetrachloride (SnCl4) becomes the standard Sn precursor, for Ge different gasses, like germane (GeH4) and digermane (Ge2H6) are used attempting to archive high Sn incorporation and high material quality. While Ge1-xSnx films with the same high Sn content can be obtained regardless of the used precursor, the advantages and disadvantages of each precursor are discussed in this work. The use of Ge2H6 is accompanied by high growth rates, being favorable in applications where relatively thick films are needed, such as laser structures. On the other hand, with a relatively low growth rate, GeH4 provides a greater thickness control, achieving clear and sharp interfaces in heterostructures. For this reason, GeH4 is the appropriate precursor for quantum transport or spintronic.
The biggest challenge in heterostructure designs is going up and down in Sn content. The growth of a Ge1-ySny on a Ge1-xSnx, y<x, or SiGeSn layer cannot be performed by increasing the growth temperature. Post-annealing processes lead to strong crystallinity degradation of the already grown layer by strong Sn diffusion or Sn segregation due to the limited thermal stability of Ge1-xSnx alloys.
In this work, we address simple methodologies to enhance the gradient or step Sn content without changing the process temperature. Controlling only the carrier gas flow while keeping the standard growth parameters constant, high-quality Ge1-xSnx alloys with uniform Sn content up to 15 at.% are obtained. The proposed method acts as guidance to produce Ge1-xSnx heterostructures that can be extended to any CVD reactor, independently of the used precursor, GeH4 or Ge2H6. Different devices structures are presented proving the applicability of the isothermal multilayer growth.

Figure 1
A Renewed Focus on Surface Chemistry for Advanced Logic-Node Epitaxial Growth Processes
Authors: Margetis Joe , Tolle John 
Published: November 2022

Increased CMOS logic and memory scaling has forced chip architectures into 3D design spaces such as finFET, GAA, nanosheet, etc. These applications require epitaxial structures to be grown in complicated and restrictive geometries which are composed of an increasingly different range of materials. Epi growth selectivity to conventional dielectric materials such as SiO2 and SiNx as well as less conventional materials like SiOxN1-x, Al2O3, and SiOCN must be maintained as usual. However changing demands on epi doping levels and thermal budgets places a large burden on conventional selectivity approaches, which most-often rely on higher HCl partial pressures or HCl etch-back steps. Cl2 etch-back processes have also been used in limited cases as an alternative to HCl, but apart from that, new selective epi growth technology has become somewhat stagnant.
The 3D nature of advanced logic architectures means that epi must also be grown on multiple crystal surface orientations like the (100), (110), and (111). For epitaxial growth processes, which by-definition are highly sensitive to the starting surface structure, this represents unique challenges to epitaxial engineers. New approaches to achieve orientation selective growth is now also paramount. Each surface orientation can have different growth rates, etch rates, and dopant incorporation efficiencies which can result in undesirable morphology, defects, and inhomogeneous chemical compositions. Depending on the application the growth rate may need to be maximized on one surface and minimized on another, for example to facilitate “bottom-up” growth from the (100) surface. In other instances, the growth rates may need to be matched as closely as possible, for example to achieve symmetric “diamond-shaped” epi-growth on a Si fin.
These issues are at a fundamental level related to surface chemical interactions and finding new solutions will require a molecular-level understanding. In this work we present a fundamental chemical view of these challenges using both theoretical (density functional theory) calculations and in-situ surface analytical results. We analyze the reactive sites on dielectric surfaces and how various deposition precursors interact with these sites. Based on these results we will discuss alternative and/or novel routes to achieving selective epitaxial growth. We apply similar methods to analyzing the structure and reactivity of the Si (100), (110), and (111) surfaces and how deposition precursor molecules react on each surface. Our results reveal why changing Si surface orientations can result in such varied reactivity and ultimately in differing growth and etching rates. We similarly use these results to suggest methods for controlling facet/plane selective epitaxy and/or etching. Central to both dielectric and facet selectivity is precursor engineering, which entails designing new molecules to customize their reactivity (or lack of reactivity) toward specific dielectric surfaces or surface orientations.

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Quantum-Ready Germanium and Silicon
Authors: Scappucci Giordano 
Published: November 2022

The semiconductor industry knows how to make and integrate billions of excellent transistors. What materials do we need to integrate excellent qubits at large scale for the quantum information age of tomorrow? What are the properties that we search in these materials to make them quantum-ready? I will focus on isotopically-engineered, strained silicon-germanium heterostructures enabling high-performance hole spin-qubits in germanium and electron spin qubits in silicon. In particular, I will make a case for the germanium quantum information route [1]. Germanium is emerging as a versatile material to realize devices capable of encoding, processing and transmitting quantum information. I will examine the materials science progress underpinning germanium-based planar heterostructures, review our most significant experimental results demonstrating key building blocks for quantum technology, and identify the most promising avenues toward scalable quantum information processing in germanium-based systems.
[1] G. Scappucci et al, The germanium quantum information route, Nat Rev Mater (2020). https://doi.org/10.1038/s41578-020-00262-z

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(Invited) Optoelectronic Quantum Information Processing: An All-Group IV Integrated Platform
Authors: Moutanabbir Oussama , Del Vecchio Patrick , Attiaoui Anis , Fettu Gabriel , Rotaru Nicolas , Assali Simone 
Published: November 2022

Achieving coherent optical photon-to-spin conversion is a long-sought-after strategy for surmounting current fundamental limits in optical schemes that hinder the long-distance distribution of entanglement. Moreover, photon-to-spin interfaces are also essential for a direct mapping of the quantum information encoded in photon flying qubits to stationary spin processors. However, the lack of scalable materials offering an efficient interaction with optical photons along with optimal spin properties remains a formidable obstacle hindering the development of these quantum technological components. With this perspective, this presentation will discuss strategies to address these challenges by leveraging the degrees of freedom offered by group IV (Si)GeSn semiconductors, namely strain and composition, to tailor the electronic structure and eventually fulfill these prerequisites. These innovative systems do not only have the potential to enable coherent photon-to-spin interfaces, but because of their compatibility with the semiconductor industry they will also offer scalability, manufacturability, and cost-effectiveness.
We will show that this family of semiconductors provide an additional flexibility to control the charge carrier states and achieve a selective confinement of holes. The latter benefit from a quiet quantum environment that has been at the core of increasingly reliable quantum processors and memories. However, most if not all available experimental studies of two-dimensional gas systems have been thus far focused on heavy-hole (HH) states. This is attributed to the nature of the heterostructures currently available (e.g, Ge/SiGe, InGaAs/GaAs), where compressive strain lifts the valence band degeneracy and leaves HH states energetically well above the light-hole (LH) states. We will demonstrate that tensile strained Ge/GeSn quantum wells alleviate these limitations and allow to selectively confine LH provided the strain is higher than 1%. This requires strain relaxed, high Sn content GeSn buffer layers to be used to grow Ge quantum wells with LH ground state, high g-factor anisotropy, and a tunable splitting of the hole subbands. The optical and electronic properties of these low-dimensional systems will be described and discussed. Spin injection and coherent control will also be addressed. Additionally, qubit designs exploiting the ability to engineer LH states and the Ge large spin-orbit coupling allowing fast all-electrical spin-manipulation schemes will also be presented and discussed.
Update on Systematic Cycle and Calendar Aging of NMC and NCA 18650 Li-Ion Batteries
Authors: Wittman Reed M , Fresquez Armando , Chalamala Babu , Preger Yuliya 
Published: November 2022

The true useful life of secondary Li-ion batteries is currently not well characterized. 80% of initial capacity, a decades old metric for vehicle applications, is a common endpoint in literature cycling studies and commercial cell specification sheets. As such, much is not known about cell performance beyond this metric. The 80% cutoff may not be applicable for non-vehicle applications, like grid energy storage, where there are different requirements for performance. Degradation data beyond the 80% capacity threshold is needed to make these evaluations.
To address this, we have been conducting a multi-year study of both cycling and calendar aging of 18650 cells. During this study, LiNixCoyAl1-x-yO2/NCA, and LiNixMnyCo1-x-yO2/NMC cells have been cycled at systematically varied temperature, state of charge (SOC) ranges, and cycling rates. Cells were cycled at different state of charge (SOC) ranges (0-100%, 20-80%, and 40-60%), temperatures (15, 25, and 35 °C) and discharge rates (0.5C, 1C, 2C, and 3C). Additionally, we present data from a concurrent calendar aging study at different temperatures (15, 25, and 35 °C) and SOCs (25, 50, and 90%). Our group has previously reported on trends for cycle aging down to 80% capacity [1]. Here, we present an update on performance of cells cycled beyond 80% capacity to an end of life (EOL) of 40% capacity and cells undergoing calendar aging.
Results so far suggest that SOC range continues to be the largest factor in capacity fade rate for both chemistries. Combining stress factors (NMC at high SOC and low temperature) causes rapid capacity fade beyond what would be expected by simple addition of degradation rates from the individual stress factors. Depending on the conditions of cycling, so called knee points do not always appear when a cell is cycled beyond 80%. When a knee point occurs varies by cycling conditions. We also consider additional metrics by which battery performance can be measured such as round-trip efficiency (RTE), total discharged energy, and internal resistance (IR). And find that IR increases generally matches well with capacity fade and appear to increase dramatically at observed knee points. For the calendar aging study, we find that holding cells at higher SOCs and temperatures generally increases the rate of fade. This study represents the broadest public report of post 80% capacity cycling across multiple chemistries. It will inform cell lifetime prediction and allow for better utilization of battery systems.
Sandia National Laboratories is a multi-mission laboratory managed and operated by National Technology & Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525. SAND2022-5089 A
References:

1Preger et al. “Degradation of Commercial Lithium-Ion Cells as a Function of Chemistry and Cycling Conditions” J. Electrochem. Soc.,
2020
, 167, 120532.
Modeling Cathode/Separator/Lithium Metal Sandwich Including Porous Electrode Effects and Plating/Stripping - Proper Formulation, Transformation, and Efficient Numerical Simulation
Authors: Uppaluri Maitri , Mishra Lubhani , Subramaniam Akshay , Jang Taejin , Subramanian Venkat R. 
Published: November 2022

The high theoretical capacity (3860 mAh g-1) and electrochemical potential of lithium (-3.040V v/s standard hydrogen electrode) makes it a promising candidate as a negative electrode for next-generation batteries.1 However, lithium electrodeposition on the metal anode surface creates dendrites that can lead to short-circuiting of the cell and loss of cyclability.
There have been several approaches to modeling lithium electrodeposition in literature. Our past work entailed modeling the deposition as a moving interface, where the equations undergo coordinate transformation to track the changes in concentration and potential as deposition occurs.2 We have also shown that inducing convection in the boundary conditions at the moving interface that properly conserves the mass of lithium in the domain.3

The electrodeposition of lithium on the metal anode produces signatures in the voltage response of the cell. In the past, we have shown that these signatures can be simulated with models that capture the transport phenomena during electrodeposition.
This work extends our previous approaches to model the electrodeposition on the surface of the metal anode for a full-cell configuration, which includes a porous cathode. The influences of lithium electrodeposition on the voltage response for different cathode materials are analyzed.

References

D. Lin, Y. Liu, and Y. Cui, Nat. Nanotechnol., 12, 194 (2017).

M. Uppaluri, A. Subramaniam, L. Mishra, V. Viswanathan, and V. R. Subramanian, J. Electrochem. Soc., 167, 160547 (2020).

L. Mishra et al., J. Electrochem. Soc., 168, 092502 (2021).
Decomposition Pathways of EC and Effects of Additives: Accounting for Liquid, Gas, and Solid Phase Reactions during the First Charge
Authors: Kerber Brian M , Guillot Sarah Lucienne , Usrey Monica Lee , Zhou Liu (Amy) , Du Peng , Peña-Hueso Adrián 
Published: November 2022

The majority of lithium-ion batteries (LIBs) utilize carbonate-based electrolytes, due to the good lithium solvation, electrochemical stability, and electrode passivation.1 Studies regarding decomposition pathways and other reaction mechanisms2-4 of carbonates in LIBs are abundant in the literature but few attempt to quantify total losses of these solvents. Quantitative measurement of solvent loss from the electrolyte would significantly inform the comprehensive picture of electrolyte reaction mechanisms in the cell. Furthermore, this approach allows for the study of any effects additives may have on carbonate solvent decomposition. For example, organosilicon (OS) additives have been shown to reduce gassing and improve high temperature cycling in carbonate-based LIBs,5 but their quantitative impact on EC decomposition is not known.
In this poster, we detail our methodology for quantitatively tracking and characterizing different forms of ethylene carbonate (EC) decomposition in a LIB pouch cell as well as the effects of organosilicon additives on these reactions. This study focused on the loss of EC after the first charge when the majority of SEI formation occurs. Liquid phase composition, including both EC and its decomposition products, was quantified by NMR analysis (1H and 19F) of extracted electrolyte using internal standards (LiPF6 and 1,4-bis(trifluoromethyl)benzene). Gas phase decomposition was characterized by a combination of the Archimedes method (to quantify gas volume) and GC-MS analysis (to determine gas composition). Finally, the impact of OS additives on the decomposition pathways of EC was examined. Inclusion of OS molecules reduces EC decomposition during the first charge, predominately by reducing the amount of liquid phase decomposition.

1Xu, K. Chem. Rev.
2004, 104, 4303-4417.

2 Campion, C.; Li, W.; Lucht, B. Thermal Decomposition of LiPF6-Based Electrolytes for Lithium-Ion Batteries. Journal of the Electrochemical Society
2005, 152, A2327.

3 Seo, D.; Chalasani, D.; Parimalam, B.; Kadam, R.; Nie, M.; Lucht, B. Reduction Reactions of Carbonate Solvents for Lithium Ion Batteries. EC Electrochemistry Letters
2014, 3, A91-A93.

4 Xing, L.; Li, W.; Wang, C.; Gu, F.; Xu, M.; Tan, C.; Yi, J. Theoretical Investigation on Oxidative Stability of Solvents and Oxidative Decomposition Mechanism of Ethylene Carbonate for Lithium Ion Battery Use. J. Phys. Chem. 2009, 113, 16596-16602.

5 Guillot, S.L.; Usrey, M.L.; Peña-Hueso, A.; Kerber, B.M.; Zhou, L.; Du, P.; Johnson, T. Reduced Gassing in Lithium-Ion Batteries with Organosilicon Additives. J. Electrochem. Soc.
2021, 168, 030533-030543.
Dynamics of Lithium Microstructure at Lithium Metal and Graphite Anodes Probed with in Operando Pulse EPR
Authors: Szczuka Conrad , Ackermann Jörg , Schleker P. Philipp M. , Jakes Peter , Eichel Rüdiger-A. , Granwehr Josef 
Published: November 2022

Lithium microstructure formation is the limiting factor preventing the application of lithium metal anodes and, to some degree, fast-charging of graphite anodes, because of enhanced cell degradation and risks of short-circuits. To improve mechanistic understanding and develop prevention strategies, a complementary analytical tool set is necessary.
Contributing to non-invasive in operando techniques, we present pulse electron paramagnetic resonance (pEPR) with a practical sampling rate of 100 microseconds, providing a global view on lithium microstructure formation and evolution.[1] pEPR experiments offer an estimate of the dimension and size distribution of the morphology that is in line with post-test SEM characterization. For lithium metal anodes, the sampling rate is sufficient to observe dynamic morphology changes that evolve for several seconds after fresh lithium deposition, attributed to surface smoothening, comparable to recently observed heating-induced healing of dendrites.[2] For graphite anodes, lithium plating can be followed at C-rates up to 18C. Quantitative measurements reveal an exponential increase of deposited lithium mass upon galvanostatic charge. The plating onset is pinpointed to the characteristic voltage drop well below 0 V vs. Li/Li+.[3] After stopping the charge at intermediate states of charge, the partial intercalation of lithium can be monitored at OCV, identifying two kinetic domains and the amount of remaining dead lithium.
[1] C. Szczuka, J. Ackermann, P. Philipp, M. Schleker, P. Jakes, R.-A. Eichel, J. Granwehr, Commun. Mater.
2021, 2, 20.
[2] L. Li, S. Basu, Y. Wang, Z. Chen, P. Hundekar, B. Wang, J. Shi, Y. Shi, S. Narayanan, N. Koratkar, Science.
2018, 359, 1513–1516.
[3] C. Uhlmann, J. Illig, M. Ender, R. Schuster, E. Ivers-Tiffée, J. Power Sources
2015, 279, 428–438.

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Hydro-to-CathodeTM Customizable Cathode Materials Made from Recycled Elements
Authors: Liu Yadong , Deng Haixia , Gratz Eric , Wang Yan 
Published: November 2022

With the explosively growth of battery usage from consumer electronics to electric vehicles, and large scale on/off-grid renewable energy storage, a large quantity of spent batteries that once powered those devices has been generated and will accelerate within the next decade and beyond. To avoid tons of spent batteries ending up in landfills, which would be hazardous wastes and could cause severe environmental pollution, we developed a highly cost-effective and energy-efficient technology “Hydro-to-Cathode” to recover the precious elements (Li, Ni, Mn, Co, etc.) from the spent batteries and make them into new cathode materials and batteries to power new devices.
Without extracting and separating the elements in the leached solution like the traditional hydrometallurgy approach does, Ascend Elements starts directly with the impurity-removed and adjusted solution to make high quality precursor for cathode materials. By controlling the conditions of precursor reactions and sintering process, we can make cathode materials with a wide range of particle sizes (2~16 µm), single crystal/polycrystalline, porous or dense intraparticle structure, and different compositions, including LiNi1/3Mn1/3Co1/3O2 (NMC 111), LiNi0.5Mn0.3Co0.2O2 (NMC 532), LiNi0.6Mn0.2Co0.2O2 (NMC 622), LiNi0.8Mn0.1Co0.1O2 (NMC 811), LiNi0.83Mn0.06Co0.11O2 (Ni 83), and LiCoO2 (LCO). The recycled cathode materials show as good as, or even better performance than cathode materials made from newly mined salts. Our unique Hydro-to-CathodeTM process significantly reduces the steps and costs to recover and recycle cathode materials from spent batteries.