bluuebunny/crossref_metadata_2025 huggingface dataset:
(Invited) All-Solid Battery Interfaces and Research in the Toyota-ECS Young Investigator Fellowship
Authors: Arthur Timothy Sean
Published: September 2023

Advances in hybrid and electric vehicle technologies combined with a demand for green initiatives have motivated necessary diversification in energy storage research. To achieve customer expectations for hybrid and electric vehicles, new battery systems with higher energy densities, power densities and cycle life than the current state-of-art are needed. Post Li-ion battery systems, such as solid-state batteries, are at the forefront of research and development for the future of mobility.

ECS and the Toyota Research Institute of North America (TRINA), have partnered to create the ECS Toyota Young Investigator Fellowship since 2014. The fellowship supports young faculty members conducting electrochemical research in green energy technology. The purpose of this fellowship is to encourage young professors and scholars to pursue innovative research in sustainability including next generation solid-state batteries.

Here, we will show the progress of fundamental research of all-solid-state battery (ASSB) interfaces at TRINA. In addition, we will take a look at the history and relationship of TRINA and the ECS in the Toyota-ECS Young Investigator Fellowship. Throughout the years, the knowledge and relationships built through the Fellowship immensely supports the progress of post lithium-ion batteries. Finally, we show deep appreciation and will highlight key technical achievements of Toyota-ECS Young Investigator Fellowship winners in battery technology.

Figure 1
Multiscale Modeling of Heterogeneous Interfaces in All Solid-State Batteries
Authors: Wan Liwen , Kim Kwangnam , Dive Aniruddha Mukund , Wang Bo , Heo Tae Wook , Wood Marissa , Wood Brandon C.
Published: September 2023

Ion transport and degradation at the solid-electorlyte/cathode interfaces dictate the performance of all solid-state batteries. For example, it has been routinely observed that in many superionic oxide conductors, Li-ion transport kinetics are orders of magnitude slower at the interfaces, such as grain boundaries or interfaces with common electrode materials, compared to the bulk phases. Upon electrochemical cycling, interdiffusion and/or electrolyte/cathode decomposition at these interfaces can further deteriorate Li-ion transport kinetics. Therefore, the ability to understand, predict and precisely control ion transport kinetics and the degree of interfacial degradation are critical and would have a transformative impact on the development of solid-state battery technologies for practical applications. Here I will address the need of a multiscale and multiphysics modeling framework to understand Li-ion transport mechanisms at complex interfaces and predict the kinetics of Li-ion transport in solid-electrolyte/cathode composite architectures that are relevant for all solid-state Li batteries. I will also emphasize the importance of using a closely coupled theory-experiment approach to reveal the atomic details of the interfaces and unravel the degradation mechanisms of interfaces and its impact on Li-ion transport. I will use the garnet-type solid-state electrotype and lithium cobalt oxide cathode as an example to demonstrate the predictive power of such a multiscale, multiphysics modeling framework towards establishing the correlations between ion transport and local atomic structure, chemical environment, and mesoscopic microstructure features in the cathode/electrolyte composites.

This work was sponsored by the Office of Energy Efficiency and Renewable Energy, Vehicle Technologies Office and was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. An award of computer time was provided by the Innovative and Novel Computational Impact on Theory and Experiment (INCITE) program. This research used resources of the Argonne Leadership Computing Facility, which is a DOE Office of Science User Facility supported under Contract DE-AC02-06CH11357.
Cycling Efficiency Improvement of Solid-State Batteries-Laser Textured Interfaces
Authors: Yan Shuo , Guo Deliang , Yim Chae-Ho , Merati Ali , Baranova Elena A. , Weck Arnaud , Abu-Lebdeh Yaser
Published: September 2023

Solid-state lithium metal batteries (SS-LMBs) with ceramic electrolytes have attracted significant interest towards their potential to produce safe and powerful storage devices. Among ceramic electrolyte materials utilized in SS-LMBs, non-flammable perovskites (La2/3-xLi3xTiO3, LLTO) are cost-effective and have a wider electrochemical window than conventional liquid electrolytes (> 5V). However, the high interfacial resistance at the LLTO/cathode interface restricts the reversible capacity and the cycling efficiency of SSLMBs. Herein, a novel approach of laser texturing at the interface was investigated as a solution to these two challenges.

In this study, the laser-texturing technique was first used to produce micro-patterns on the side of the LLTO against the cathode. This increased surface contact area provided more pathways for Li-ion migration at the interface, leading to decreased interfacial resistance and an improved battery energy density. A few drops of liquid electrolyte were added to fill the void spaces between the laser-textured LLTO and the cathode.

Overall, this study conceptually proved the effectiveness of using laser texturing to improve the interfacial contact. Further efforts are needed to optimize the pattern design and establish a more stable interface that could enable long-term cycling of the SS-LMBs.
The Impact of Li Surface Heterogeneity and Morphology on Performance in Solid-State Batteries
Authors: Westover Andrew S , Sahore Ritu , Herbert Erik , Tsai Wan-Yu , Sacci Robert L , Kalnaus Sergiy
Published: September 2023

Solid-state Li metal batteries have the potential to enable both fast charging and more than a 30% increase in energy density. Two of the most pervasive and limiting challenges in these materials are the interface between the Li metal and the solid electrolyte and the formation of Li filaments that penetrate the solid electrolyte leading to cell shorting. Currently, most efforts to solve these problems are focused on solid electrolytes. Here we present our work investigating the Li side of the equation. This work compares four thin Li sources (<40 µm), three rolled Li from commercial suppliers, and a fourth prepared in-house using thermal evaporation. Using X-ray photoelectron spectroscopy (XPS) and attenuated total internal reflection infrared spectroscopy (ATIR), we determined that the surface layers on these different Li films varied significantly in composition and thickness. Subsequent electrochemical testing of these films in liquid, polymer, and ceramic solid electrolytes, showed that variation in the surface thickness and chemistry significantly impacted the interfacial resistance. Furthermore, an analysis of cell failure due to shorting led to the clear conclusion that in addition to the surface contamination, the Li microstructure also had a significant impact in determining when failure will occur.

Acknowledgments: Simon Thompson and the DOE EERE Vehicle Technology office Battery Material Research Program for funding supporting this work.
Application of Artificial Interphase on Ni-Rich Cathode Materials Via Hybrid Ceramic-Polymer Electrolyte in All Solid State Batteries
Authors: Liao Cheng Hung , Chen Chia-Chin , Jeng Ru-Jong , Wu Nae-Lih (Nick)
Published: September 2023

Among many cathode materials, nickel-rich LiNi0.83Co0.12Mn0.05O2 (NCM 831205) has been spotlighted as one of the most feasible candidates for next-generation LIBs because of its high discharge capacity (~200 mAh/g). However, NCM 831205 shows significant performance degradation, which is mostly attributed to cation mixing, surface side reactions, and intrinsic structural instability originating from the large volume changes during repeated cycling.

Conventional lithium ion batteries (LIB) normally use flammable nonaqueous liquid electrolytes, resulting in a serious safety issue in use. In this respect, all-solid-state batteries (ASSB) are regarded as a fundamental solution to address the safety issue by using a solid state electrolyte in place of the conventional liquid one.

This work employed lithium sulfonate (SO3Li) tethered polymer, obtained from sulfonation of commercial polymer, to serve as the artificial protective coating on the active NCM831205 of the cathode for ASSB based on hybrid PEO-ceramic solid electrolyte.

The coating layer should prevent direct contact of electrolyte with the cathode, thus avoid the negative effects such as microcracks of NCM831205 and undesired CEI formation. The preparation of hybrid ceramic-polymer electrolyte through a solvent-free process. The hybrid electrolytes exhibit good flexibility and processability with respect to pure ceramic and pure PEO polymer electrolyte.

It is demonstrated that the hybrid electrolytes can penetrate into cathode under 60°C, providing a good Li+ transfer channel inside the battery. Moreover, the sulfone based polymer protective coating could effectively improve the electrochemical stability of the NCM831205 without sacrificing the battery performance.

Keywords: NCM831205, Artificial Polymer Coating, All-Solid-State Batteries
Optimizing Sulfur Utilization in High Loading Cathode for All-Solid-State Lithium-Sulfur Battery
Authors: Kindle Michael , Yu Zhaoxin , Marty Daniel , Xu Yaobin , Zeng Chao , Wang Chongmin , Bao Jie , Xu Zhijie , Lu Dongping
Published: September 2023

All Solid-state Lithium-Sulfur battery (ASSLSB) possesses a great promise in providing a safe, high energy density, and low cost battery technology for vehicle electrification and grid energy storage. To achieve practically high specific energy in ASSLSB (e.g., >400 Wh/Kg), sulfur cathodes with high areal capacity (>6 mAh cm-2) are essentially needed to offset the relatively low working voltage of elemental sulfur cathode (1.9 V vs. Li). This requires high mass loading sulfur cathodes by maximizing both sulfur content in the whole electrode and sulfur utilization rate to reduce the parasitic weights. An optimal electrode architecture featuring sufficiently connected sulfur/solid electrolyte/carbon triple interfaces is desired to enable sulfur’s fast accessibility to electron and Li-ion simultaneously. Due to the non-flowability of those three solid components, however, it is very hard to maximize the contact of trip solid phases, which need new insights of the materials design and processing technology.

This work looks at carbon microstructures and their impact on triple-point contact between electrochemically active sulfur, carbon, and the solid-state electrolyte (SSE) that comprises most composite cathodes in ASSLSB systems. While significant work has gone into understanding and developing novel carbon host structures for liquid Li-S cells for improving sulfur utilization, polysulfide trapping, better understanding is needed for ASSLSBs. Specifically, how sulfur infiltration, loading, and spatial distribution within the porous carbon host impacts sulfur utilization. Understanding how the infiltrated sulfur that resides in the porous carbon host connects with both carbon and solid electrolyte networks across the whole electrode structure and maintains its robustness during the repeated cell cycling is needed to achieve full utilization in high sulfur loading electrodes. The solid sulfur cathode system examined in the present study is a composite of porous carbon, sulfur, and a sulfide-based solid electrolyte. A combination of porous carbon hosts is investigated and correlated to the cell performance at practical conditions. Advanced characterization and computational tools are used to further elucidate the key parameters for high sulfur utilization in ASSLSBs with high sulfur loading cathodes. Details of the study will be presented and discussed at the meeting.

Reference:

(1) Nagata, H. and Y. Chikusa (2016). "All-Solid-State Lithium–Sulfur Battery with High Energy and Power Densities at the Cell Level." Energy Technology 4(4): 484-489

(2) Banerjee, A., et al. (2020). "Interfaces and Interphases in All-Solid-State Batteries with Inorganic Solid Electrolytes." Chemical Reviews 120(14): 6878-6933.
(Invited) Addressing Energy/Power Tradeoffs in Composite Solid-State Battery Electrodes
Authors: Dasgupta Neil P.
Published: September 2023

Solid-state batteries (SSBs) have seen a dramatic increase in research in recent years because of their ability to address safety challenges associated with flammable liquid electrolytes, and the potential to enable Li metal anodes. However, SSBs present unique challenges, including high interfacial impedances, accommodation of mechanical stresses due to solid-solid interfacial contact, and (electro)chemical instabilities that can evolve during dynamic cycling conditions. Furthermore, a significant challenge facing the scale-up of SSBs is to improve our understanding of processing science needed to enable manufacturing.

While a significant amount of attention has been paid recently to the Li metal anode/electrolyte interface, there has been significantly less work on the cathode side of the SSB. In SSBs, the cathodes are typically composites of the active material and solid electrolyte (SE) phases, which experience rate limitations. Analogous to porous electrodes with liquid electrolytes, the rate capability of these composite solid-state electrodes is strongly dependent on electrode thickness (electrode capacity) and electrode composition/microstructure. These results in tradeoffs between energy and power density, which are exacerbated at high charging rates.

To address these challenges, we have recently applied operando optical microscopy to directly observe state-of-charge (SoC) gradients in composite solid-state electrodes, using graphite as a model active material [1]. To describe mass transport in these composite electrodes, continuum-scale modeling was performed, which illustrates the critical role of the electrode microstructure and tortuosity on rate capability. These in situ observations are consistent with ex situ measurements of Li-graphite half-cells, where we quantify the rate capability as a function of areal capacity.

To overcome these limitations, we engineered composite SSB electrodes with controlled microstructure and 3-D architectures. These electrodes showed improved homogeneity in the local SOCs throughout the electrode thickness, enabling high-rate cycling capabilities. Overall, the insights presented here will enable new strategies to overcome power/energy tradeoffs in SSBs with composite electrodes.

[1] A. L. Davis, V. Goel, D. W. Liao, M. N. Main, E. Kazyak, J. Lee, K. Thornton, N. P. Dasgupta, ACS Energy Lett. 6, 2993 (2021)
Improving Cell-Level Specific Energy for All-Solid-State Lithium Sulfur Batteries
Authors: Lin Yi , Dornbusch Donald , Viggiano Rocco P.
Published: September 2023

All-solid-state lithium-sulfur (Li-S) batteries are considered as one of the top choices toward 500 Wh/kg of specific energy, a key metric for an energy storage system that enables large regional electric aircrafts. Many obstacles remain, such as S utilization in the cathode, cyclability with regard to both cathode and anode as well as electrode-electrolyte interfaces, and effective means to increase the S content within the all-solid-state cell architecture. The latter is directly related to cell-level specific energy when considering the weights of all battery cell components. In this presentation, we discuss the efforts in both cathode optimization and cell-level improvement toward increasing the overall specific energy. Various strategies in improving S utilization and reducing the solid electrolyte layer thickness will be presented.
(Invited) Multi-Scale Implications of Material Heterogeneity on Solid State Battery Performance
Authors: Hatzell Kelsey
Published: September 2023

Solid state batteries are comprised of an ensemble of materials with varying structural, mechanical, chemical, and transport properties1,2. Orchestrating these materials to act synergistically and enable high power and high energy densities requires understanding how solid state electrodes and electrolytes can be engineered to enable: (1) efficient ion and electron transport and (2) maintain uniform contact between components during electrochemical cycling. Bulk processing approaching (e.g. coating, sintering, densification, etc.) do not lead to much control over material properties across various length scales (nano-to-meso). Material heterogenities exist within the cathode, solid electrolyte, and anode. In the cathode, the solid electrolyte and active material can be non-uniformly distributed leading to bottlenecks for transport and non-uniform active material utilization. In the solid electrolyte, active and passive heterogenities can influence how the ion moves between the anode and cathode and cause deleterious current focusing dynamics3,4. Finally, at the anode voiding and contact loss can occur in alkali metal anodes. This talk discusses our recent work combining operando synchrotron studies, electrochemical characterization, and advanced material characterization to unravel the implications of heterogenity on performance and degradation mechanism in solid state batteries.

[1] Zaman, Wahid, and Kelsey B. Hatzell. "Processing and manufacturing of next generation lithium-based all solid-state batteries." Current Opinion in Solid State and Materials Science 26.4 (2022): 101003.

[2] Ren, Yuxun, and Kelsey B. Hatzell. "Elasticity-oriented design of solid-state batteries: challenges and perspectives." Journal of Materials Chemistry A 9.24 (2021): 13804-13821.

[3]Dixit, Marm B., et al. "Polymorphism of garnet solid electrolytes and its implications for grain-level chemo-mechanics." Nature Materials 21.11 (2022): 1298-1305.

[4]Ren, Yuxun, Nicholas Hortance, and Kelsey B. Hatzell. "Mitigating Chemo-Mechanical Failure in Li-S Solid State Batteries with Compliant Cathodes." Journal of The Electrochemical Society 169.6 (2022): 060503.
Controls Stack Pressure Induced Fracture Using Microstructural Modulation in Solid-State Batteries
Authors: Singh Avtar , Finegan Donal P. , Hamilton Dylan , Zhu Juner , Li Wei , Martin Trevor R.
Published: September 2023

All-solid-state batteries (ASSBs) provide higher energy densities and safer alternatives to Li-ion batteries by incorporating Li-metal anode and inflammable solid electrolytes. To match the increased capacity of metallic anodes, ASSBs require high-energy-density cathode materials such as LiNixCoyMn1-x-yO2 (also known as NMC cathode) blended with a solid-state electrolyte (SSE). However, a key challenge is resolving the interfacial incompatibility between the active particulate material and the solid-state electrolyte within these composite cathodes. To obtain intimate contact between SSE and the active material, an external load (or stack pressure) needs to be applied during the processing and service life of cell. Nevertheless, such densification of cathode composites can lead to grain boundary fracture and/or complete particle disintegration. Therefore, the present work utilizes a microstructural modulation procedure to alleviate stack pressure-induced fracture in a polycrystalline cathode. Accordingly, a thermodynamically consistent computational framework is developed to understand the interplay between the stack pressure, microstructural modulation, and fracture behavior for polycrystalline NMC secondary particles embedded in a sulfide-based solid electrolyte. A phase-field fracture variable is employed to consider the initiation and propagation of cracks in the active material and SSE. This modeling framework is implemented in the open-source finite element package (MOOSE) to solve three state variables: concentration, displacement, and the phase-field damage parameter. A systematic parametric study is performed to explore the effects of stack pressure, aspect ratio, and the crystal orientation of grains on the chemo-mechanical performance of the composite electrode. We also quantitatively validate the numerical model with experimental investigation using state-of-the-art Nano-CT (Compact tomography) technique. The findings of this study offer predictive insights for designing solid-state batteries with reduced fracture evolution and stable performance.

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(Invited) Processability of Solid-State Batteries
Authors: Belharouak Ilias , Dixit Marm , Amin Ruhul , Muralidharan Nitin , Essehli Rachid , Balasubramanian Mahalingam
Published: September 2023

Solid-state batteries are promising energy storage alternatives that can achieve high energy densities be enabling Li metal anode and high voltage cathodes. When combined with long cycle life, improved safety, and low cost (<$100/kWh) the value proposition of solid-state lithium metal battery becomes more and more relevant. There are, however, significant materials and processing challenges that disrupt the materialization of working SSBs at present. Recent reviews clearly informed that the energy and power densities of the reported SSBs fall short in comparison with the state-of-the-art Li-ion batteries. The technical barriers to be addressed in the long-term include achieving areal capacities in the range of 3-10 mAh cm-2 with less than 10% excess Li anode, and more than 70% active that material loading in solid-state composite cathodes that are assembled against thin electrolytes which can withstand current densities higher than 1 mA cm-2, and yet enables higher coulombic efficiencies. Cell design calculations show that solid electrolytes with <100 µm thicknesses and Li metal anode with <50 µm thickness are necessary to achieve energy densities comparable or higher than the state-of-the-art lithium-ion batteries. The processability and integration of thick composite cathodes, thin solid electrolytes, and thin lithium metal anode into cell configurations in scalable fashions are of utmost significance to improve the value proposition of near market SSBs.
Enabling the High-Temperature Co-Sintering of NMC and Li-Stuffed Garnets through Thermochemical Stability Studies
Authors: Hoft Richard Mariano , Ivanov Daniel , Wachsman Eric
Published: September 2023

Solid-state batteries based on lithium-stuffed oxides ceramics promise to improve the safety and energy density over current commercial batteries. Li7La3Zr2O12 (LLZO) is one of the most promising of these solid electrolytes as it has high ionic conductivity and low reactivity with Li metal. The major challenge of this material is its high interfacial resistance with commonly used cathodes such as LiCoO2 (LCO) and particularly Li2NixMnyCozO2 (NMC) due to the solid-solid nature of the contact and the thermochemical instability of these materials when mixed at high temperatures.

This work experimentally elucidates the nature of the thermochemical instability between LLZO and NMC by providing experimental validation of computational work performed by collaborators and exploring various parameters such as sintering atmosphere, Li content, and processing temperature. Improving our understanding of these two compounds in sintering environments will allow for minimizing the interfacial resistance between LLZO and NMC to provide a pathway for producing a solid-state ceramic Li metal battery that can achieve theoretical capacities at commercially applicable charge rates at room temperature.

Preliminary results have already determined several trends in NMC/LLZO thermochemical instability. XRD and TGA/DSC results have shown a heavy dependence on the composition of NMC used. Namely, the higher the nickel content of the NMC, the more it will react with LLZO at high temperature. However, the theoretical capacity of NMC increases with increasing nickel content such that NMC622 appears to be the optimal composition because of its higher theoretical capacity compared to NMC111 while reacting less than NMC811. The atmosphere during sintering has been shown to also be important with pure O2 gas providing better stability at temperatures above 1000°C compared to argon gas. Furthermore, increasing the Li concentration in the LLZO has been shown to increase the decomposition reaction of NMC and LLZO, leading to the formation of new phases.
(Digital Presentation) Electrochemical Properties of Ta-Doped Li7La3Zr2O12 Ceramic Electrolyte Sintered with Ga2O3 Additive
Authors: Inada Ryoji , Akimoto Keigo , Yamazaki Yusuke
Published: September 2023

A garnet-type oxide with the formula of Li7La3Zr2O12 (LLZO) has attracted much attention because of its high Li ion conductivity at room temperature, excellent thermal performance, and high stability against Li metal.1,2) However, poor interfacial connection causes non-uniform Li plating and intergranular penetration of Li dendrite in polycrystalline LLZO when the cell is cycled particularly at high current densities, resulting in internal short-circuit failure.3,4) It has been pointed out that the tolerance for Li dendrite growth into LLZO is influenced by many factors such as the interfacial resistance between LLZO and Li anode, cell stacking pressure and microstructure (density and grain size) of LLZO. In this study, we fabricated Ta-doped LLZO (Li6.55La3Zr1.55Ta0.45O12) solid electrolytes with Ga2O3 additive and investigated the effects on the microstructure and electrochemical properties.

Ta-doped LLZO with Ga2O3 additive were synthesized via a conventional solid-state reaction process. 1-7 mol % Ga2O3 powder was mixed with calcined Ta-doped LLZO powder. The mixture was pelletized and then sintered at different temperatures with an Al-free crucible. In XRD analysis, each sintered sample has a cubic garnet phase and diffraction peaks from other phases were not detected. In SEM observation, microstructure of sintered sample was strongly influenced by sintering temperature and Ga2O3 addition, due to the sintering with liquid Li-Ga-O phase during high temperature sintering.5, 6) The high total (bulk + grain-boundary) ionic conductivity above 1 mS cm-1 at room temperature was obtained in samples composed of large grains with the size of several 10 to 100 µm. However, the tolerance for Li dendrite growth characterized in a symmetric cell is improved remarkably in the samples with uniform microstructure composed of fine grains with the size of below 5 µm. Since the interfacial resistance between Li and solid electrolyte was adjusted to the same level, the difference in tolerance for Li dendrite growth is mainly attributed to the difference in microstructure depending on both the sintering condition and the amounts of Ga2O3 addition.

References

[1] R. Murugan, V. Thangadurai, W. Weppner, Angew. Chem., Int. Ed. 46, 7778−7781 (2007).

[2] A.J. Samson, K. Hofstetter, S. Bag, V. Thangadurai, Energy Environ. Sci. 12, 2957−2975 (2019).

[3] E.J. Cheng, A. Sharafi, J. Sakamoto, Electrochimica Acta 223, 85−91 (2017).

[4] R. Inada, S. Yasuda, H. Hosokawa, M. Saito, T. Tojo, Y. Sakurai, Batteries 4, 26 (2018).

[5] Y. Matsuda, A. Sakaida, K. Sugimoto, D. Mori, Y. Takeda, O. Yamamoto, N. Imanishi, Solid State Ionics 311 (2017) 69−74.

[6] Y. Yamazaki, S. Miyake, K. Akimoto, R. Inada, Batteries 8, 158 (2022).
Li Metal Anode with a LiZn Alloy Interlayer for Li-Metal Polymer Batteries
Authors: Delaporte Nicolas , Perea Alexis , Collin-Martin Steve , Léonard Mireille , Matton Julie , Gariépy Vincent , Demers Hendrix , Clément Daniel , Rivard Etienne , Vijh Ashok
Published: September 2023

All-solid-state batteries (ASSB) require stable and safe Li metal anode, which needs surface preparation to increase lithium diffusion and impede the formation of dendrites. In this work, the formation of a thin LiZn layer on lithium metal using sputter deposition is reported. This method was selected due to the absence of solvents and by-products generated during the modification, for its rapidity and because the formation of the alloy is performed in a clean and controlled atmosphere. Zinc has been chosen for its low cost and high Li+ ion diffusion coefficient of the corresponding LiZn alloy that is 1000 times higher than lithium. Different parameters for the Zn deposition were investigated such as the distance between the Zn target and Li foil, the effect of substrate tilt and the direct current applied to the target. Electrochemical performance of LiFePO4/solid polymer electrolyte/Li ASSB demonstrated the superiority of the LiZn anodes and the clear influence of deposition parameters on the durability and performance at high C-rates. Scanning electron microscopy images of the cross-sectional view of LFP/SPE/Li stackings extracted from pouch cells after cycling showed an evident migration of Zn into the bulk Li metal anode as well as the formation of AlZn nanoparticles. In addition, the formation of Li dendrites was effectively reduced for the cells made with the LiZn-protected Li metal anode. Finally, we reported an interesting observation concerning the influence of sputter conditions on the variation of morphology of Li grains.
Operando Characterization of Plating and Stripping Dynamics of Li-Mg Alloy Anode and Sulfide Solid Electrolyte Interface
Authors: Zhao Lihong , Wu Chaoshan , Ai Qing , Guo Liqun , Chen Zhaoyang , Liang Yanliang , Lou Jun , Fan Zheng , Yao Yan
Published: September 2023

All-solid-state lithium metal batteries are projected to offer one of the highest specific energy among rechargeable batteries, positioning them as a front-runner for electric vehicle applications. Lithium metal anodes outperform conventional graphite anodes in terms of cell-level energy density. However, maintaining a conformal metal–electrolyte contact is a great challenge. The volumetric change of the lithium metal anode during stripping produces voids, which deteriorates the Li–electrolyte contact. To address this challenge, β-phase Li solid solution (i.e., Li-Mg alloy) has been shown to exhibit improved contact with the solid electrolyte during stripping. Moreover, Li solid solution has a similar electrochemical potential as Li, making it a potential replacement for Li metal anodes without sacrificing cell-level energy density. In this study, we show that the chemical properties of the alloy play an essential role in the morphological stability of metal–solid electrolyte interface. We compare the stripping behavior of pure Li and Li-Mg alloy anodes in argyrodite electrolyte and characterize the morphological evolution of the interface using operando scanning electron microscopy (SEM). We also analyze the electro-chemo-mechanical properties of Li and Li alloy anodes during stripping with galvanostatic electrochemical impedance spectroscopy (GEIS) to compare the influence of composition change and interfacial void on the electrode overpotential and interface resistance. Our research visualizes the morphological and compositional evolution of alloy metal anode during stripping and rationalizes their improved interfacial stability against solid electrolytes.

Acknowledgment: This work was supported by the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy (EERE) under the Vehicle Technologies Program under Contract DE-EE0008864.

Figure 1
Influence of Interfacial Voids and Grain Boundary Conductivity on Depletion Kinetics of Sodium Metal Anodes in All-Solid-State Batteries
Authors: Chatterjee Sourav , Tonks Michael , Gardner Will , Sessim Marina
Published: September 2023

An electrochemical micro-scale phase-field model is developed to simulate the stripping and plating kinetics of a Na-metal anode in all-solid-state Na-ion batteries. In this model, in addition to the metallic anode and ceramic separator regions, a highly conductive but Na-poor region representing the free space is assumed to simulate the shrinking of the Na-anode during electro-stripping and its growth during plating. For a perfect anode/separator interface, we find that the growth and depletion kinetics are linear. However, the presence of multiple interfacial voids at the anode/separator interface causes deviation from this linear behaviour. Finally, we show that depletion kinetics is also proportional to the ratio of the grain boundary conductivity to that of the grain conductivity (σgb/σg) in the separator phase, either with or without interfacial voids.
Hybrid Material Concepts for Thiophosphate-Based Solid-State Batteries
Authors: Vargas-Barbosa Nella Marie , Puls Sebastian , Woolley Henry Michael
Published: September 2023

Solid-state batteries (SSBs) could replace conventional lithium-ion batteries due to the possibility of increasing the energy density of the cells by using lithium metal as the anode material.[1] Among the many electrolyte candidates for lithium SSBs, the lithium thiophosphates are particularly interesting due to their high ionic conductivities at room temperature (>1 mS/cm). However, the (electro)chemical stability of these solid electrolytes is limited and not fully compatible with state-of-the-art high-potential cathode active materials[2] or the lithium metal anode.[3] At the cell level, the formation of interparticle voids between the various battery components (solid electrolyte, cathode active material, anode material, additives, decomposition interphases) hinder the net transport during cycling. To address the latter electro-chemo-mechanical challenges, we are exploring hybrid material approaches, in which we combine established materials (solid electrolytes, liquid electrolytes and/or polymer additives) with state-of-the-art cathode active materials and test their electrochemical performance in solid-state battery (half-)cells. Such cycling results are complimented by detailed electrochemical transport studies in symmetrical cells using DC polarization and electrochemical impedance spectroscopy, including transmission-line modeling. ex.situ chemically-specific spectroscopic methods are used to support our hypotheses and interpretation of the electrochemical results. Taken together, we attain a better picture on the positive (or negative) role hybrid materials play in SSBs. In this talk, we will showcase two hybrid systems, namely ionic liquid/thiophosphate lithium hybrid electrolytes and conductive polymers additives in NMC-based catholyte composites for Li6PS5Cl cells. The first part of the talk we will discuss the results in which we evaluate the performance of liquid electrolyte-solid electrolyte materials against lithium metal using galvanostatic electrochemical impedance spectroscopy. In the second part, we elucidate the partial ionic and electronic transport in polymer electrolyte-Li6PS5Cl-NMC catholytes as a function of polymer content using impedance spectroscopy and its effect in the cycling performance, both the stability as well as the magnitude of the discharge capacities. These systems serve as a good starting point for the further development and incorporation of hybrid materials in SSBs.

Literature: [1] W. G. Zeier and J. Janek Nature Energy, 2016, 1, 16141. [2] G.F. Dewald, S. Ohno, M.A. Kraft, R. Kroever, P. Till, N.M. Vargas-Barbosa, J. Janek, W.G. Zeier Chem. Mater. 2019, 31, 8328. [3] L. M. Riegger, R. Schlem, J. Sann, W. G. Zeier, J. Janek, Angew. Chem. Int Ed 2021, 60, 6718.

Figure 1
Effect of Nanostructured Inorganic Ceramic Filler on Poly(ethylene oxide)-Based Solid Polymer Electrolytes
Authors: Kirchberger Anna Maria , Walke Patrick , Nilges Tom
Published: September 2023

In view of the ongoing changes in energy science and technology, the possibilities of energy storage are getting increasingly important. In particular, storing electrical energy is more complex than with fossil fuels.

Lithium-Ion batteries are the most commonly used media for energy storage, but they also have some safety-related problems: toxic decomposition products can leak out and the devices can catch fire. Research is underway to find alternatives to minimize this potential hazards. Great improvements in safety matters can be achieved by replacing liquid electrolytes with ceramic/polymer hybrid electrolytes. These hybrid electrolytes combine the advantages of polymer electrolytes with the benefits of inorganic ceramic fillers.1 Flexibility, good contact ability and in addition the good processability is provided through the polymer. The inorganic ceramic filler in contrast adds mechanical stability, opens new pathways for the Lithium-Ions and can enhance the stability of the electrolyte.

Figure 1: different Lithium-ion pathways in ceramic/polymer hybrid electrolytes dependent on different filler amounts. 2

In this work the impact of the manufacturing method on the conductivity of a series of electrolytes was examined. Therefore, hot pressing, solution casting and electrospinning were tested. Also, different distribution methods for the particles in the material were tested to monitor the influence of agglomeration on the conductivity. The materials were characterized regarding the crystallinity using X-Ray diffraction, the surface and particle distribution was monitored with SEM/EDX, the thermal character was investigated using DSC, the conductivity was determined using impedance spectroscopy and the electrochemical behavior was tested using cyclic voltammetry. Furthermore, the Arrhenius equation was used to interpret the results of impedance spectroscopy regarding their activation energy. The addition of inorganic ceramic fillers leads to an enhancement of the ionic conductivity in PEO based electrolytes and increases processability and stability of the electrolyte. In this work conductivities of 10-5 S/cm were reached at room temperature. The performance of the electrolyte was increased above three orders of magnitude compared to a PEO electrolyte without inorganic ceramic fillers.

Walke, P.; Kirchberger, A.; Reiter, F.; Esken, D.; Nilges, T., Effect of nanostructured Al2O3 on poly(ethylene oxide)-based solid polymer electrolytes. Zeitschrift für Naturforschung B
2021,
76 (10-12), 615-624.

Chen, L.; Li, Y.; Li, S.-P.; Fan, L.-Z.; Nan, C.-W.; Goodenough, J. B., PEO/garnet composite electrolytes for solid-state lithium batteries: From “ceramic-in-polymer” to “polymer-in-ceramic”. Nano Energy
2018,
46, 176-184.

Figure 1
(Invited) High-Performance Lithium Metal Batteries
Authors: Thangadurai Venkataraman
Published: September 2023

The success of rechargeable lithium-ion batteries (LIBs) has brought evident convenience to human society, but state-of-the-art LIBs with a carbon anode are approaching their energy density limits. Li metal is considered the ultimate anode material due to its ultra-high theoretical specific capacity of 3860 mAh g-1, which is more than 10 times higher than lithiated graphite. Nonetheless, Li anode suffers from poor safety and low cycling efficiency due to its high reactivity. Electrolytes that work with Li anode should possess excellent stability against Li metal or form a highly passivating interface. It is also critical to control the amount of Li in the cell, preferably having no excess Li at the anode side.1 In this presentation, next-generation electrolytes that enable such types of high-performance Li metal batteries will be discussed, including advanced liquid electrolytes,2 garnet-type ceramic electrolytes3–5 and hybrid electrolytes.6,7

References

C. Zhou, A. J. Samson, M. A. Garakani, and V. Thangadurai, J. Electrochem. Soc., 168, 060532 (2021).

C. Zhou et al., Energy Storage Mater., 42, 295–306 (2021) https://doi.org/10.1016/j.ensm.2021.07.043.

S. P. Kammampata, R. H. Basappa, T. Ito, H. Yamada, and V. Thangadurai, ACS Appl. Energy Mater., 2, 1765–1773 (2019).

S. P. Kammampata, H. Yamada, T. Ito, R. Paul, and V. Thangadurai, J. Mater. Chem. A, 8, 2581–2590 (2020).

C. Zhou, A. J. Samson, K. Hofstetter, and V. Thangadurai, Sustain. Energy Fuels, 2, 2165–2170 (2018).

S. Bag, C. Zhou, P. J. Kim, V. G. Pol, and V. Thangadurai, Energy Storage Mater., 24, 198–207 (2019) https://doi.org/10.1016/j.ensm.2019.08.019.

C. Zhou, S. Bag, T. He, B. Lv, and V. Thangadurai, Appl. Mater. Today, 19, 100585 (2020) https://doi.org/10.1016/j.apmt.2020.100585.
Thermodynamic Modelling and Experimental Study of Nasicon Sub-Systems for Application as Solid State Electrolyte
Authors: Gonde Shivani , Sergeev Dmitry , Yazhenskikh Elena , Müller Michael
Published: September 2023

Solid state electrolytes are crucial for enhancement of the safety and practicability of batteries. NASICON (
Na Super Ionic Conductor) is proposed as replacement for β″-Al2O3 [1], because of its excellent structural strength and conductivity which is attributed to its structure wherein Na migrates in 3D voids providing ionic conductivity of 0.2 S·cm-1 (300 °C). Furthermore, the processing temperature is relatively low (~700 °C), and high Na abundance makes it cheaper than Li-ion batteries.

The NASICON phase with formula Na1+xZr2SixP3-xO12 [0≤x≤3] is found to be conductive and is a part of the complex Na2O-SiO2-P2O5-ZrO2 system. For a successful material design, thermodynamic properties (phase equilibria, heat capacity, stability, etc.) for all subsystems must be known, and for prediction of the properties, a reliable and consistent database is imperative. To accomplish these milestones, a thermodynamic database of the quaternary oxide system including the NASICON phase is being developed using Calculation of Phase Diagrams (CALPHAD) method.

As part of this development, underlying binary systems such as Na2O-ZrO2 and ternary systems such as ZrO2-SiO2-P2O5 are studied. After preliminary results, the phase diagram construction is in progress with DTA/TG, XRD, and the experimental data along with literature values after critical analysis will be utilized for generation of Gibbs energies for all phases in the system. Using the thermodynamic dataset obtained, phase equilibria are predicted in agreement with the experimental data. The current state of work will be presented.

References:

B. Goodenough: “Fast Na+-ion transport in skeleton structures”, Mater. Res. Bull. 11(2) (1976) 203-220.

Warhus: “Thermodynamics of NASICON (Na1+xZr2SixP3-xO12)”, J. Solid State Chem. 72(1) (1988) 113-125.

Figure 1
Examining Electrochemical and Mechanical Behavior of Amorphous and Crystalline Sulfide-Based Solid-State Electrolytes
Authors: Efaw Corey M. , Chen Bor-Rong , Park Bumjun , Barnes Pete , Davis Paul H. , Liaw Boryann (Bor Yann) , Dufek Eric J. , Li Bin
Published: September 2023

Traditional liquid electrolytes used in lithium-metal batteries have severe safety issues, poor power density, as well as thermal and electrochemical instability that prevent scaling to newer applications, such as electric vehicles. Sulfide-based solid-state electrolytes (SSEs) are viable for addressing many of the issues seen with liquid electrolytes. However, one of the key hindrances to the use of sulfide-based SSEs is the understanding of repeatable processing of highly conductive, stable material. There are limitations in producing electrolyte with known defect types and density, as well as degree of crystallinity. The degree of crystallinity greatly effects electrochemical properties, such as ionic conductivity, due to the change in ionic pathways through the electrolyte. However, other hindrances to SSE capabilities, such as interfacial stability and mechanical integrity, are not noted as a function of crystallinity. Here, multiple forms of characterization were utilized to confirm structural information on dry ball milled Li7P3S11 (LPS) SSEs. A range of crystallinity of pelletized electrolytes were then analyzed with different electrochemical and mechanical tests to evaluate the viability of SSEs in operation. There is particular interest in the near-amorphous regime of crystallinity, where minimal differences are seen in electrochemical capabilities, though there is uncertainty in the possible benefits observed for interfacial compatibility and in mechanical properties. Electrochemical impedance spectroscopy (EIS) and symmetric cell cycling were utilized to examine the bulk and interfacial capabilities of electrolytes, all operated under various loads with a specialty designed load cell. Mechanical properties were analyzed with mechanical testing on different scales, from bulk loading down to atomic force microscopy mapping and nanoindentation testing. With this wide array of characterizations, a wholistic understanding of slightly varied crystallinity of sulfide-based SSE is accomplished.
Three-Dimensional Porous Flower-like CoMoO4 As Cathode for Li-O2 Batteries
Authors: Xing Pengcheng
Published: September 2023

Lithium-oxygen batteries (LOBs) are considered to be the next-generation energy storage systems due to their high energy density (~ 3500 Wh kg-1).1 However, the insulating and bulk lithium peroxide discharge product causes sluggish decomposition, increasing overpotential and reducing cycle stability, so it is necessary to find cathode materials with excellent oxygen reduction reaction and oxygen evolution reaction performance.2 Mixed transition metal oxides have attracted much attention because of their feasible oxidation states, high energy density, and high conductivity. Here, Three-Dimensional Porous flower-like CoMoO4 (3DF-CM) was synthesized via a universal and low-cost hydrothermal method, which is to be used as an efficient electrocatalyst in an oxygen electrode for high-performance LOBs. Morphologically, the 3DF-CM with high electrical conductivity has a large surface that can improve charge transport and promote delithiation during recharge. As a result, the battery based on 3DF-CM as a cathode exhibited an outstanding discharge capacity and a long-term life performance.
Visualization of the Lithium Sulfur Electrochemistry
Authors: Shi Fangyi , Xu Zheng-Long
Published: September 2023

Taken advantage of a high theoretical energy density of 2567 Wh kg-1, lithium sulfur batteries (LSBs) have been considered promising candidates for next-generation energy storage systems. Tremendous efforts have been devoted to improving the battery performance by preparing smart nanostructures. However, detailed reaction mechanisms and the principles of tailoring reaction paths remain unclear. In-situ transmission electron microscopy (TEM) is a powerful technique to probe the dynamic processes of electrochemical reactions at a high spatial resolution and in real-time. Through in-situ TEM study with a solid cell, we revealed the correlation between sulfur volume expansion and the porosity of carbon nanofibers. Further, by developing an in-situ TEM equiped with a graphene-based liquid cell (GLC), where liquid electrolyte and TiN-C/S nanoparticles are encapsulated between two graphene sheets, we disclosed the nucleation and growth dynamics of solid Li2S from soluble polysulfides. Very recently, using operando optical microscopy, we found liquid sulfur droplets formation during charging at room temperature, which is much lower than the melting point of sulfur. The liquid sulfur indicates superior kinetic features from its flowing and reshaping natures. More interestingly, the preservation of liquid sulfur is strongly linked to the substrate chemistry, where solid sulfur forms from the edge of 2D materials. It is believed that in-situ microscopic investigation of sulfur cathodes would not only shed new light on understanding of reaction mechanisms but also provide fundamental guidelines to design better LSBs.