bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electrochemical-Piezoelectric Mechanism for Dendrite Growth
Authors: Gao Tianhan , Lu Wei 
Published: November 2022

On immersing two lithium metal electrodes in a solution containing lithium salt and applying a voltage, lithium metal will deposit on the electrode connected to the lower voltage. This process is known as electrodeposition. It has been widely observed that under moderate currents, lithium ions do not deposit to a flat surface but rather spontaneously form sharp needle shapes known as dendrites. Dendrite formation is a major barrier for realizing the lithium metal battery, which not only causes capacity loss but also leads to internal short circuit and safety hazard [1].
We report a discovery that the use of a soft piezoelectric film as separator can effectively suppress the formation of lithium dendrite and stabilize the lithium surface during electrodeposition system [2, 3]. When the film is deformed by any local protrusion because of surface instability of the deposited lithium, a local piezoelectric overpotential is generated to suppress lithium deposition on the protrusion. We have established a theory that integrates electrochemistry, piezoelectricity and mechanics. We developed multiphysics computations to simulate dendrite growth in contact with a piezoelectric film. We find that the dendrite-suppression capability is over 6 orders stronger than the limit of mechanical blocking by any separators or solid-state electrolytes. Simulations show that the mechanism ensures deposition to form a flat surface even if the initial substrate surface has significant protrusions, suggesting its robustness and effectiveness against manufacturing defects. We show that the mechanism is so strong that even a weak piezoelectric material is highly effective, opening up a wide range of materials.

REFERENCES

Liu, G. and Lu, W. A model of concurrent lithium dendrite growth, SEI growth, SEI penetration and regrowth. Electrochem. Soc.(2017) 164: A1826.

Liu, G., Wang, D., Zhang, J., Kim, A. and Lu, W. Preventing dendrite growth by a soft piezoelectric material. ACS Mater. Lett.(2019) 1: 498-505.

Gao, T., Rainey, C. and Lu, W. Piezoelectric mechanism and a compliant film to effectively suppress dendrite growth. ACS Appl. Mater. Interfaces. (2020) 12: 51448–51458.
(Invited) U.S. DOE Lithium Metal Solid-State Battery R&D
Authors: Thompson Simon T. , Smith Patricia H. , Duong Tien Q. 
Published: November 2022

Decarbonizing transportation through electrification requires less expensive, higher energy density batteries made from earth-abundant materials to displace internal combustion engines. Suitable solid-state electrolytes (SSEs) that facilitate lithium metal anodes by blocking Li dendrite formation represent a promising pathway to high-energy density cells. In a similar manner, SSEs that block the polysulfide shuttle could facilitate sulfur cathodes with even higher energy density that avoid issues of critical materials and supply chain constraints coupled to transition metal oxide-based cathodes.
Interest in solid-state batteries has increased rapidly in recent years. There are examples of solid-state batteries (SSBs) in commercial automotive applications; however, achieving wider adoption requires SSBs operating without the need for heating or excessive applied cell pressure. Several solid-state electrolyte chemistries (e.g., sulfides, ceramics, polymers, halides) are under development, but key issues remain unresolved in the case of each electrolyte chemistry.
The U.S. Department of Energy Vehicle Technologies Office supports R&D encompassing all of these candidate electrolytes for solid-state batteries through the Advanced Battery Materials Research program. The R&D portfolio prioritizes: improving electrolytes through modified composition or synthesis to increase room-temperature Li+ conductivity and mitigate Li dendrite penetration; improving interfaces to address chemical or electrochemical reactivity, to decrease impedance, and to improve Li plating and stripping; and improving suitability for high-volume manufacturing of solid-state lithium metal batteries by improving mechanical properties and demonstrating thin, defect-free, large-area SSE layers.
This presentation comprises solid-state lithium metal battery R&D priorities and accomplishments in the context of meeting DOE targets for energy density, cycle life, and cost. It will also emphasize the importance of SSBs to U.S. DOE strategy for increasing domestic lithium-based battery manufacturing and securing the U.S. position in next-generation battery innovation.
Insights into the Crystal Structure of Halide Solid Electrolytes and Li Diffusion
Authors: Liu Zhantao , Chien Alex , Wang Shuo , Lin Zihao , Liu Jue , Mo Yifei , Chen Hailong 
Published: November 2022

Lithium halides with general formula Li3MX6 (M = metals such as Y, In, Yb or Sc; X = Cl or Br) have attracted significant attention because of their promising room temperature conductivities and high oxidative stability[1]. Li-ion mobility in these halides is strongly affected by the synthesis method and parameters. In Li3YCl6 with a hexagonal-close-packed (hcp) anion framework, the ionic conductivity is commonly observed to decrease with increased crystallinity. While in Li3YBr6 with a face-centered-cubic (fcc) anion framework, the ionic conductivity increases with increased crystallinity. So far there is no clear explanation for such opposite trends in these two otherwise very similar crystal structures. Ab initio molecular dynamics (AIMD) simulation[2] suggested higher ionic conductivity and lower activation energy in Li3YCl6 than inLi3YBr6, which also does not agree well with the experimental observation that Li3YBr6 commonly shows higher conductivity than Li3YCl6. Above-mentioned unexplained observations and inconsistencies imply that likely some critical structural features of these halides that strongly impact ionic diffusion are not yet explored nor taken into consideration. Here, we report our recent findings in the crystal structure of Li3YCl6 and Li3YBr6 and the design, synthesis and electrochemical testing of a few new halide compounds designed based on the new findings. The crystal structures are investigated with using ex situ and in situ synchrotron X-ray diffraction (XRD) and neutron diffraction (ND). Our study[3] demonstrated that the discrepancies between simulated and experimental results in Li3YBr6-type structure is partly caused by the grain boundary. Through PDF data analysis, we provide experimental evidences of cation local ordering in ab plane and stacking fault along c-direction in Li3YBr6-type structure. The lower ionic conductivity in low crystallinity is owing to the blockage of Li diffusion channel along c-direction caused by the stacking fault. Moreover, a new tetrahedral Li-site is identified, which may be critical in understanding the Li diffusion behaviors. Via rationally tuning Li occupancies at the tetrahedral and octahedral sites, low Li diffusion barriers can be achieved, which is in consistence with theoretical calculation results.
[1] T. Asano, A. Sakai, S. Ouchi, M. Sakaida, A. Miyazaki, S. Hasegawa, Advanced Materials
2018, 30, 1803075.
[2] S. Wang, Q. Bai, A. M. Nolan, Y. Liu, S. Gong, Q. Sun, Y. Mo, Angewandte Chemie International Edition
2019, 58, 8039-8043.
[3] Z. Liu, S. Ma, J. Liu, S. Xiong, Y. Ma, H. Chen, ACS Energy Letters
2021, 6, 298-304.
Elucidating MnO2 Reaction Mechanism By Multi-Modal Characterization in Aqueous Zn-MnO2 Batteries
Authors: Kankanallu Varun , Zheng Xiaoyin , Lin Cheng-Hung , Zmich Nicole , Ge Mingyuan , Chen-Wiegart Yu-chen Karen 
Published: November 2022

Aqueous Zn-ion batteries has attracted great attention in recent years, as a promising candidate for grid energy storage applications. An aqueous system offers intrinsic safety, high ionic conductivity contributing improved power capability and raw materials that are more earth abundant and environment friendly. Numerous promising reports haven been focusing on the Zn/MnO2 system owing to its low cost, moderate discharge potentials and with improved reversibility in the mild aqueous electrolyte. However, many questions remain unanswered regarding its reaction mechanism. The different reaction mechanisms including Zn+2 insertion, H+ insertion, chemical conversion reaction including the combined intercalation and conversion reaction mechanism, and the dissolution-deposition of the manganese oxide.
In this work, we aim to unravel the reaction mechanism by a systematic multimodal synchrotron characterization. This work discusses the galvano-static charge-discharge process of aqueous Zn-MnO2 batteries using operando measurements, which provides us with a direct insight into the phenomenon and can be directly correlated to the battery's electrochemical response. The multimodal techniques include operando X-ray diffraction to study the structural phase change of the cathode active material, operando X-ray absorption spectroscopy to probe the local structure changes and transmission X-ray microscopy studies to observe the key morphological events. Overall, this multimodal approach gives us an insight into the reaction mechanism enabling us to better design Zn-MnO2 batteries for practical applications.
Atomic Dispersed Ce/Ti Onto Layered Double Hydroxide Substrate Via Atomic Layer Deposition for Efficient Oxygen Evolution Reaction
Authors: Liu Ziqi , Lee Min Hwan , Garcia ThomasJae , Li Haoyu 
Published: November 2022

Recently, transition metal based layered double hydroxides (LDHs) based materials have attracted attention for the enhancement of oxygen evolution reaction (OER) performances due to their unique structural property, high specific capacitance, facile synthesis process and low cost. [1,2] Atomic layer deposition (ALD) is a powerful technique for realizing highly dispersed nano-species at the atomic level with a precise control over the size, shape, and composition by leveraging its self-limiting nature of surface reactions. ALD precursors could be readily combined with LDH structures due to the abundant hydroxy group on the surface of LDH structure. The additional ALD-derived doping can regulate the electronic structures of original LDH and further strength the synergetic effects between the host and doped metals for enhancing electrocatalytic activities.[3]

In this study, a simple and effective method of introducing Ce as a third metal was used to prepare high-performance Ni/Co-LDH based electrodes: hydrothermal approach followed by an ALD process, using Ni foam as the substrate to achieve the growth of Ni/Co nanostructures. Smooth 2D LDH plates of a uniform structure with high surface area and abundant active sites were synthesized. The resultant CoNi-LDH@5Ce and CoNi-LDH@5Ti exhibit optimal activity and stability toward OER. In particular, CoNi-LDH@5Ce exhibits excellent OER performance with a small overpotential of 270 mV to reach 50 mA cm-2. ALD-treated samples exhibit a decreased charge transfer resistance, indicating a more efficient OER. Furthermore, both CoNi@5Ti and CoNi@5Ce show lower ohmic resistance of 1.5 Ω, which is additionally beneficial to OER performance. The enhanced performance could be attributed to a synergic effect between the doped elements (Ce, Ti) and base transitional metals (Co, Ni). Furthermore, metal oxides – especially cobalt oxide – generated on the surface during ALD process is conjectured to have contributed to an acceleration of O-O bond formation during OER process.

References

[1] Z. Jiang, Z. Li, Z. Qin, H. Sun, X. Jiao, D. Chen, .
[2] T. M. Masikhwa, M. J. Madito, D. Y. Momodu, J. K. Dangbegnon, O. Guellati, A. Harat, M. Guerioune, F. Barzegar, N. Manyala, .
[3] L. Lv, Z. Yang, K. Chen, C. Wang, Y. Xiong, Adv. Energy Mater.
2019, 9, 1803358.
Utilizing 3D Electrolysis Models to Link Transport to Cell Design and Performance
Authors: Lopata Joseph Steven , Weidner John W. , Cho Hyun-Seok , Shimpalee Sirivatch 
Published: November 2022

Computational fluid dynamics (CFD) has been employed extensively for modeling fuel cells, but electrolysis has lacked this degree of attention in literature. As electrolysis commercialization advances, the desire to use numerical methods to aid the engineering process grows. The work described in this presentation aims to link channel/manifold geometry, porous media design, and operating conditions to cell performance in the context of mass transport and identify important unknown input quantities to which models are particularly sensitive. CFD is applied to electrolysis systems to quantify the impact of two-phase flow patterns and porous media properties on energy losses, primarily those linked directly to the presence of the gas phase.
3D models for proton exchange and alkaline electrolysis devices are summarized. For proton exchange electrolysis, a homogeneous two-phase model was built in order to estimate the species composition at the anode and how operating conditions and porous transport layer (PTL) properties influence distributions. The model suggests that cell performance is particularly sensitive to the evaporation rate and PTL permeability when the contribution of the gas-phase reaction is considered. A similar model was applied to alkaline diaphragm electrolysis to study effects of the manifolds on the flow distribution and thereby local performance. Current and gas crossover were correlated with cell geometry and altered by the cell potential and feed rate.

Figure 1
Optimal Dynamic Operation of Grid-Integrated Hydrogen Energy System: A Techno-Economic Analysis
Authors: Haggi Hamed , Brooker Paul , Sun Wei , Fenton James M. 
Published: November 2022

Rapidly decreasing costs of solar energy and policies that encourage decarbonization are driving solar photovoltaic (PV) farms to be paired with large scale and longer duration energy storage. Hydrogen generation from renewable energy can provide long-term, clean energy storage and can be used in the power industry through fuel cells or combustion turbines, used as chemical feedstock for industry, or as a fuel for transportation. Production costs of hydrogen via electrolytic methods mainly depends on the electricity price, capital costs, and equipment capacity factors. To be cost effective with other types of energy storage, a desired hydrogen price of $1/kg by 2030 will be needed. This study focuses on a techno-economic analysis of a grid-integrated microgrid that includes hydrogen systems (i.e. electrolyzer, compressor, storage tank, and stationary fuel cell), high penetration of solar PV, and battery energy storage systems. The microgrid is operated in a way to minimize the total operation and investment costs and maximize the revenue of the microgrid owner by exchanging power with the grid. While previous work [1] (one hour steady-state time steps) considered a fixed conversion efficiency for the electrolyzer, this study focuses on dynamic operation of the electrolyzer using polarization curves and non-linear conversion efficiency (modeled based on actual cell voltage, cell current, and Faraday efficiency) for more realistic results.
Simulation results show that the hourly conversion efficiency of the electrolyzer highly depends on stack operating conditions (cell voltage and current density, the size of the electrolyzer, the temperature, hydrogen demand, etc.). This results in different microgrid optimization and scheduling of energy assets, and consequently the hydrogen production cost. Sensitivity analysis on the PV penetration, current density of the electrolyzer, and changes in asset capital costs will be presented.
[1] Hamed Haggi, Paul Brooker, Wei Sun, James M. Fenton, “Hydrogen and Battery Storage Technologies for Low-Cost Energy Decarbonization in Distributed Networks”, arXiv, 11 (2022). https://doi.org/10.48550/arXiv.2202.02711
(Invited, Digital Presentation) Electrocatalyst and Electrolyte Engineering for Oxygen Evolution in Acidic Media
Authors: Escudero-Escribano Maria 
Published: November 2022

The slow kinetics of the oxygen evolution reaction (OER) limits the performance of proton exchange membrane (PEM) electrolysers. Only iridium-based oxides are both reasonably active and stable for the OER in acidic electrolytes [1], and high amounts of Ir are needed at the anode of PEM electrolysers. In addition, the lack of stable support materials limits the utilisation of Ir. Designing novel electrocatalysts with enhanced OER activity and stability in acidic media remains a great challenge. In this talk, I will present some recent strategies aiming to understand and engineer the interfacial structure and properties for oxygen evolution electrocatalysis. We have developed self-supported high surface area nanostructured Ir-based networks as highly active electrocatalysts for OER [2]. These networks, prepared by alternating sputtering of Ir and Co, followed by selective Co leaching, show a unique morphology and combine excellent mass activity with promising stability [2]. In addition, our group is working in the development of an easy and affordable method to prepare IrOx catalysts by controlled electrodeposition of Co and Ni in a deep eutectic solvent followed by galvanic displacement [3]. By controlling the conditions during the galvanic displacement, we tune the morphology and thus the electrocatalytic properties for OER. Finally, we have investigated the role of both composition and concentration of the acidic electrolyte (perchloric and sulphuric acid) on the OER electrocatalytic performance of Ir nanoparticles [4]. Our work highlights the key role the electrolyte plays in the performance of Ir-based electrocatalysts during rotating disc electrode measurements.
REFERENCES
[1] M. Escudero-Escribano et al., Journal of Physical Chemistry B
2018, 122, 947.
[2] A.W. Jensen, G.W. Sievers, K.D. Jensen, J. Quinson, J.A. Arminio-Ravelo, V. Brüser, M. Arenz, M. Escudero-Escribano, Journal of Materials Chemistry A
2020, 8, 1066.
[3] F.B. Holde, K.N. Dalby, H. Falsig, P. Sebastián-Pascual, M. Escudero-Escribano, in prep., 2022.
[4] J.A. Arminio-Ravelo, A.W. Jensen, K.D. Jensen, J. Quinson, M. Escudero-Escribano, ChemPhysChem
2019, 20, 2956.
Enhanced Oxygen Evolution Reaction Activity of Iridium Nanostructure Supported on Mesoporous Tantalum Oxide By the SMSI Effect
Authors: Baik Chaekyung , Cha Jeong In , Pak Chanho 
Published: November 2022

The proton exchange membrane water electrolysis (PEMWE), which transforms the surplus electric energy into a form of transportable hydrogen energy, has been attracting significant attention. PEMWE has the benefits of fast response, high current operation, and gas purity compared to alkaline water electrolysis. Thus PEMWE is more suitable for hydrogen production using fluctuated renewable energies. Since iridium oxide (IrO2) catalysts are stable and fairly active in the water oxidation reaction, researchers have been focusing on increasing the activity and stability of iridium-based catalysts while reducing Ir loading level by developing binary oxide or dispersing on metal oxides [1,2]. To replace carbon support in PEMWE anode, metal oxide supports that are stable to harsh OER conditions such as titanium, neodymium, and tantalum oxides were studied for enhancing electrical conductivity with high surface area [2,3]. In this study, mesoporous Ta2O5 with a high surface area (> 100m2/g) was synthesized through the soft-template method. The Ir nanoparticles were supported on porous Ta2O5 by the formic reduction method. The self-assembling characteristic of the reduction method is attributed to the Ir coated structure of Ta2O5. XPS analysis showed the oxidation states of Ir(0) with Ta(IV) with peak shift owing to strong metal-support interaction (SMSI). The uniform Ir dispersion on the support improved electrical conductivity and electrochemically active surface area (ECSA). The electron transfers from Ta to Ir maintained high Ir3+ composition during the OER. The improved OER activity (288 mV/cm2) and mass activity (898 A/g at 1.55 V) indicates that Ta2O5 support efficiently can reduce the Ir loading levels and it was also demonstrated in MEA performance under PEMWE conditions.

References

[1] C. Ma, W. Sun, W. Qamar Zaman, Z. Zhou, H. Zhang, Q. Shen, L. Cao and J. Yang, ACS Appl. Mater. Interfaces, 12, 34980-34989 (2020).
[2] H.-S Oh, H.N. Nong, T. Reier, A. Bergmann, M. Gliech, J. Gerreira de Araújo, E. Willinger, R. Schlogl, D. Teschner, P. Strasser, J. Am. Chem. Soc., 138, 12552-12563 (2016).
[3] E. Oakton, D. Lebedev, M. Povia, D.F. Abbott, E. Fabbri, A. Fedorov, M. Nachtegaal, C. Copéret, T.J. Schmidt, ACS Catal., 7, 2346-2352 (2017).
High Resolution Characterization of Proton Exchange Membrane Water Electrolysis Anodes
Authors: Ferner Kara , Park Janghoon , Kang Zhenye , Mauger Scott A , Ulsh Michael , Bender Guido , Litster Shawn 
Published: November 2022

The current use of expensive and geographically-limited precious metal catalysts, typically iridium, in proton exchange membrane water electrolyzer (PEMWE) anodes is necessary to accelerate the sluggish oxygen evolution reaction (OER). However, high loadings of iridium catalyst drastically increase the capital costs of PEM electrolysis, while low loadings of iridium lead to a significant decline in the efficiency of hydrogen production. Thus, PEMWE anode fabrication methods must be optimized to achieve the highest performance with lower iridium loadings. Using high resolution characterization methods, we show nanoscale differences in anode morphology between different IrO2 anode fabrication methods, such as spray coated versus blade coated anodes. We also explore the evolution of the electrode morphology throughout its fabrication and testing lifetime. The characterization methods used in this work include high resolution nanoscale X-ray computed tomography (nano-CT) as well as plasma-focused ion beam cross-sectioning and scanning electron microscopy (pFIB-SEM). Additionally, we present quantitative data such as solid particle and pore size distributions as well as pore network extractions derived from our image-based characterizations to elucidate the morphological differences between IrO2 anodes.
This conference presentation was developed based upon funding from the Alliance for Sustainable Energy, LLC, Managing and Operating Contractor for the National Renewable Energy Laboratory for the U.S. Department of Energy.