bluuebunny/crossref_metadata_2025 huggingface dataset:
Computational Study of Amorphous LiNb0.5P0.5O3 Cathode Coating Material Utilizing Universal Machine Learning Potential
Authors: Yoshikawa Koki , Fujiwara Yoshiya , Luong Huu Duc , Zhou Zizhen , Fujisaki Fumika , Tateyama Yoshitaka
Published: December 2024

All-solid-state batteries using sulfide-based solid electrolytes (SSEs) have been expected as promising next-generation batteries, but the low chemical stability of SSEs causes interfacial side reactions with cathode active materials (CAMs), resulting in degraded battery performance.[1] To mitigate this issue, cathode coating material (CCM) like LiNbO3 on the CAM has been introduced to prevent direct contact with the SSE.[2] Recently, it was reported that amorphous LiNb0.5P0.5O3 suppresses the interfacial side reactions compared to amorphous LiNbO3.[3] Though several computational studies on crystalline CCMs exist[4], accurate modelling of the amorphous CCM has been still challenging. In this work, adopting a universal machine learning potential (MLP) that allows reasonable level of accuracy and speed both[5], we investigated characteristics of the amorphous LiNb0.5P0.5O3. Pair distribution functions (PDFs) of amorphous LiNbO3 calculated by melt quench method[6] using first-principles (VASP[7, 8]) and MLP techniques are shown in Fig. 1 (a). The similarity indicates that MLP can calculate the amorphous structures with sufficient accuracy. We also calculated lithium and oxygen vacancy formation energies in amorphous LiNb(1-x)P
x
O3 (x = 0, 0.5, 1.0) using MLP (Fig. 1 (b)). The lithium vacancy formation energy increases with the P content, indicating that phosphorus contributes to the stabilization of Li in the CCM. Meanwhile, the oxygen vacancy formation energy is the highest for LiNb0.5P0.5O3 (x = 0.5), implying that the coexistence of Nb and P suppresses oxygen desorption associated with cation valence changes. These results can be regarded as one of the reasons for the reduced interfacial side reactions using LiNb0.5P0.5O3 as a CCM. We are also calculating lithium diffusion coefficients, density of states, and comparing the properties to crystalline CCMs, which will be discussed in the presentation.

Acknowledgement:

This study is based on the project of ‘Evaluation of All-Solid-State Battery Material and Foundational Technology Development for Next Generation (SOLiD-Next, JPNP23005)’, commissioned by the New Energy and Industrial Technology Development Organization (NEDO).

References:

[1] Q. Zhang et al., Adv. Mater., 31, 1901131 (2019).

[2] A. Banerjee et al., Chem. Rev., 120, 6878 (2020).

[3] Y. Morino et al., ACS Appl. Mater. Interfaces, 15, 36086 (2023).

[4] H. Chen et al., Chem. Mater., 35, 5657 (2023).

[5] S. Takamoto et at., Nat. Commun., 13, 2991 (2022).

[6] M. D. Kluge et at., Phys. Rev. B, 36, 4234, (1987).

[7] P. E. Blöch, Phys. Rev. B, 50, 17953 (1994).

[8] G. Kresse et al., Phys. Rev. B, 59, 1758 (1999).

Figure 1
Preventing Micro-Penetration of Li Dendrites in Solid Electrolyte through Transition Metal Segregation Layer for a Stable All-Solid-State Li-Metal Battery
Authors: Yun Heejun , Lee Eunji , Kim Youn Sang
Published: December 2024

Non-flammable all-solid-state Li-metal batteries (ASSLBs) are the most spotlighted game changers in next-generation batteries. In particular, polymer-based ASSLBs, which use a Li-ion conductive polymer composite electrolyte, are about to be released by leading companies. This is largely due to their wide compatibility with conventional Li-ion batteries, ease of processing, and cost-effectiveness. However, the failures of ASSLBs have not been fully investigated, which further retards the advancement of ASSLBs. For this reason, the understanding of the failure of ASSLBs is the last key for the commercialization of the ASSLBs. Herein, we directly prove that the ASSLBs failure with voltage noise originated from Li dendritic penetration and successfully suppressed this failure with a transition metal segregation layer coating at cathode-solid electrolyte interface. Fine-tuned electrochemical tests demonstrate that the voltage noise failure (VNF) is an electrochemical phenotype of the Li dendritic penetration in this study. Further, we visualize the penetration of the Li dendritic growth in polymer solid electrolytes for the first time with 5000 points data of laser induced breakdown spectroscopy. This dendritic growth was accelerated by the transition metal dissolution from the cathode, which was confirmed with gas chromatography, XPS, and ICP-MS results. To break the intermediate link of the failure mechanism, we designed the transition metal segregation layer at the cathode-solid electrolyte interface using Prussian blue analogue (PBA), based on density functional theory calculations. As a result, ASSLBs with PBA show remarkable performance (189 mAh g−1 at 0.5C and 232 mAh g−1 at 0.1C) and stability (94.4% capacity retention after 100 cycles), lasting up to 1200 cycles without VNF occurring. This fundamental study would certainly be a milestone for both the development of advanced ASSLBs in practical use and academic research.
Highly Ionic Conductive Polymer Interlayer for Garnet-Type Solid Electrolyte to Improve Energy Storage Performance of All-Solid-State-Batteries
Authors: Lee Young-Geun , Whitacre Jay F
Published: December 2024

Garnet-type Li6.4La3Zr1.4Ta0.6O12 (LLZTO) has been spotlighted as a promising solid-state-electrolyte for all-solid-state lithium metal batteries (ASSBs) due to high ionic conductivity, superior chemical stability against Li metal, and broad window potential (0~5 V versus Li/Li+). However, an insufficient solid-solid contact between the electrode and electrolyte brings about high interface resistance, low Coulombic efficiency, and large voltage polarization during cycling. To overcome these challenges, it is a desirable tactic to introduce an ionic conductive polymer interlayer such as novel modified polyethylene oxide (PEO). Herein, we fabricated ASSB structures that employed polyoxanorbornene-based bottlebrush polymers with PEO side chains as interlayers between the cathode and the electrolyte layer. This polymer exhibits semi-crystallinity and showcases high ionic conductivity (~0.63 mS cm-1) at room temperature due to the presence of the polyoxanorbornene backbone, which acts as an additional ion conductive agent alongside the PEO side chain, thus overcoming typical conductivity issues associated with using PEO-based materials. The resultant ASSB composed of the highly conductive polymer (HCP) interlayer demonstrates outstanding electrochemical performance including an improved specific capacity, rate performance, and cycling stability at room temperature, compared to the PEO interlayer. We will disclose data both describing the functional materials used as well as the performance of the test cells that were assembled.
(Invited) Factors Guiding the Stability Sulfide and Oxide Solid-State Electrolyte Interphases with Lithium Metal
Authors: Mitlin David
Published: December 2024

Site-specific microstructural analysis combined with interphase design is employed to understand the origin of solid-state electrolyte failure, and to promote extended electrochemical stability. For example, stable anode-free all-solid-state battery (AF-ASSB) with an argyrodite is achieved by tuning wetting of lithium metal on “empty” copper current-collector by coating it with a thin composite film of thermodynamically stable Li2Te and Cu microparticles. Cryo-FIB sectioning demonstrates a dense and uniform electrodeposit, with minimal voiding or dendrites at the collector-SSE interface. Unmodified Cu current-collector promotes inhomogeneous Li electrodeposition/dissolution, leading to a thick non-uniform solid electrolyte interphase (SEI) interspersed with voids. As another example, thin intermetallic Li2Te–LiTe3 bilayer derived from 2D tellurene stabilizes the Li-argyrodite SEI, allowing state-of-the-art electrochemical performance with conventional foils. The Li2Te–LiTe3 bilayer impedes SSE decomposition and suppresses voiding. Unmodified Li–LPSCl undergoes reduction decomposition that extends deep into the SSE, causing reactivity-induced voids in both metal and SEI. For the first time, short-circuiting Li metal dendrite is directly identified, employing 1.5 mm diameter "mini" symmetrical cell and cryogenic focused ion beam (cryo-FIB) electron microscopy. The branching sheet-like dendrite traverses intergranularly, filling the interparticle voids and forming an SEI around it. A separate study on dendrites in garnet LLZTO demonstrates that the compact's grain size distribution and internal porosity critically affect electrical short-circuiting, indicating the importance of local electronic properties. Lithium dendrites propagate intergranularly through regions where LLZTO grains are statistically smaller than the bulk average. Metal also accumulates in the otherwise empty pores of sintered compact present along the dendrite path.

Related Work:

Mechanical Milling - induced Microstructure Changes in Argyrodite LPSCl Solid-State Electrolyte Critically Affect Electrochemical Stability,
Advanced Energy Materials.
2024, in-press.

Dendrite Growth—Microstructure—Stress—Interrelations in Garnet Solid-State Electrolyte.
Advanced Energy Materials.
2024, 2303062. https://doi.org/10.1002/aenm.202303062

Stable Anode‐Free All‐Solid‐State Lithium Battery through Tuned Metal Wetting on the Copper Current Collector.
Advanced Materials

. 2022 Nov 29:2206762.

Tuned Reactivity at the Lithium Metal–Argyrodite Solid State Electrolyte Interphase.
Advanced Energy Materials
. 2023 Dec;13(46):2301338.
Li Metal Surface Modification to Stabilize Lithium-Argyrodite Interface for Sulfide-Based All-Solid-State Lithium Metal Batteries
Authors: Sim Hui-Tae , Oh Myungkeun , Park Ye-Eun , Kim Hyojin , Cho Yun-Sun , PARK Seongjin , Kim Dong-Won
Published: December 2024

Since the commercialization of lithium-ion batteries, they have faced limitation in safety and energy density. All-solid-state lithium metal batteries (ASSLMBs) can be a solution to address these issues. Among many types of solid electrolytes, sulfide-based solid electrolytes have been attracted great attention because of their high ion conductivity and ductile property. However, many researchers have reported that the interface between lithium metal and solid electrolyte is highly unstable. The lithium dendrite growth can be also occurred in the ASSLMBs by voids, cracks, grain boundaries in solid electrolyte and side reactions between lithium metal and solid electrolyte. Therefore, it is imperative to develop a protective layer that can suppress lithium dendrites and side reactions.

In our work, we removed native resistive surface layer formed on pristine lithium metal and reconstructed solid electrolyte interphases (SEI) with uniform, ion-conductive and excellent physical properties by dipping solution containing lithium nitrate in nitromethane and dimethoxyethane. The modified lithium metal is denoted as Li@NDL (lithium @ nitromethane-dimethoxyethane-lithium nitrate). We confirmed that nitromethane reacted with LiOH and Li2O on native surface of lithium to form Li3N and organic layer, which enhanced ionic conductivity and mechanical strength. The symmetric lithium cell with Li@NDL increased critical current density to 2.8 mA cm-2 and exhibited outstanding cycling stability without short circuit over 1000 hours. ASSLMB comprising Li@NDL anode and 4 mAh cm-2 NCM composite cathode maintained 80% retention after 200th cycles at 0.5 C, demonstrating our work can provide a novel surface modification of lithium metal for ASSLMBs.
All-Solid-State Li-S Cells: The Importance of Interfaces
Authors: Cruddos Joshua , Cruddos Josh , Robinson James B , Zeier Wolfgang
Published: December 2024

All solid-state batteries have long been considered the next leap forward in energy storage devices, owing to their improved safety and higher theoretical energy density than their liquid counterparts. However, even with these improvements, heavy metal positive electrode materials such as lithium nickel oxides (NMC) and lithium iron Phosphate (LFP) are not gravimetrically energy dense enough to meet the growing energy requirements of modern-day applications. One promising candidate is the lithium sulfur (Li-S) chemistry due to the high theoretical capacity and abundance of sulfur. However, designing positive electrodes with high sulfur content that is able to withstand the large sulfur morphology expansion, alongside minimizing the excess Li storage in the negative electrode has remained elusive. A solution to this is the development of “anode-free” or zero excess lithium (ZEL) cells which minimise inactive materials and mitigate the challenges of handling Li metal foils during fabrication. These offer a further enhanced energy density, additional safety improvements and more control of the negative electrode interface. However, the inefficiency of lithium plating and stripping leads to rapid capacity degradation due to the absence of an excess lithium inventory.

Here we present, to our knowledge, the development of the first zero-excess (anode free) all solid state LiS battery, composed of an Li2S-based catholyte combined with an Li6PS5CL solid electrolyte and a Ni/In negative electrode. The cell displays good capacity retention, 350 mAh g-1 Li2S after 50 cycles, and good rate capability, up to 2C. Since zero-excess cell degradation is primarily afforded to Li losses at the negative electrode, our study focuses on understanding this degradation and its relationship with the interfacial resistance at the anode-electrolyte interface. In addition, we show the affect of replacing Indium with an ionically conductive amorphous thin film as a method to reduce interfacial resistance which improves the gravimetric energy density of the cell. Finally, using X-ray computer tomography, we investigate the formation of cracks and void shifts and their subsequent effect on cycling performance, alongside the importance of pressure to enable long cycling life.

Figure 1
Near-Strain-Free Anode Architecture Enabled By Interfacial Diffusion Creep for Initial-Anode-Free Quasi-Solid-State Batteries
Authors: Ryu Minje , Kim Kwang Hee , Lee Myung-Jin , Liu Tae-Kyung , Lee Jung Hwan , Jung Changhoon , Kim Jusik , Park Jong Hyeok
Published: December 2024

Anode-free batteries, employing garnet-type solid-state electrolytes, offer a promising avenue for developing safe and high-energy-density battery technologies. However, their practical implementation is hampered by internal strain resulting from the repetitive plating and stripping of lithium metal. To address this challenge, we propose a novel approach utilizing titanium nitrate nanotubes and a silver-carbon interlayer. These components effectively mitigate the anisotropic stress arising from the recurrent formation of lithium deposition layers during cycling. The titanium nitrate nanotubes exhibit a mixed ionic-electronic conducting nature, facilitating the entry of reduced lithium into their free volume space via interfacial diffusion creep. This design achieves nearly strain-free operation with nearly tenfold volume suppression capability compared to conventional copper anodes during lithiation. Notably, our fabricated initial-anode-free quasi-solid-state battery, based on Li6.4La3Zr1.7Ta0.3O12 (LLZTO), paired with a high-voltage cathode infused with an ionic liquid electrolyte, demonstrates remarkable room temperature cyclability, exceeding 600 cycles at 1 mA cm-2, with an impressive average coulombic efficiency of 99.8%. This advancement holds significant promise for overcoming the barriers to practical realization of safe and high-performing battery technologies, paving the way for the development of next-generation energy storage solutions.
Enabling Lithium-Free Batteries through Newly Developed Lithium-Garnet with Mixed Ion and Electron Conduction
Authors: Alexander George , Wachsman Eric D
Published: December 2024

Garnet structured solid electrolyte with a lithium-metal anode and high voltage cathode is a promising battery system owing to its inherent safety with high energy density. However, integrating thick metallic lithium with garnet solid electrolyte is not viable for a scalable process due to its complexity and the excess volume of lithium-metal compared to the lithiated cathode. To overcome these challenges, “lithium-free” batteries fabricated in a discharged state of the battery with only the current collector at the anode side is garnering increasing attention.1 The major drawback of a “lithium-free” battery with a garnet solid electrolyte is the limited lithium plating capacity and poor coulombic efficiency. To address this, we developed a mixed ion electron conducting (MIEC) garnet with comparable lithium-ion and electron conductivity at room temperature.2 We demonstrate that with a porous MIEC framework supporting a thin dense garnet solid electrolyte the cells can be cycled with no dendrite-induced shorting, at room temperature and sub-zero temperature without any stack pressure. Through various electrochemical characterization and electron microscopy the role of porous MIEC was elucidated.

Huang, Wen‐Ze, Chen‐Zi Zhao, Peng Wu, Hong Yuan, Wei‐Er Feng, Ze‐Yu Liu, Yang Lu et al. "Anode‐free solid‐state lithium batteries: a review." Adv. Energy Mat.
12, 2201044 (2022).

Alexander, George V., Changmin Shi, Jon O’Neill, and Eric D. Wachsman. "Extreme lithium-metal cycling enabled by a mixed ion-and electron-conducting garnet three-dimensional architecture." Nat. Mat.
22, 1136-1143 (2023).
Interface Dynamics and Heterogeneities in Solid-State Batteries
Authors: Vishnugopi Bairav Sabarish , Naik Kaustubh Girish , Mukherjee Partha P.
Published: December 2024

Solid-state batteries are promising next-generation energy storage devices that can offer higher energy densities when compared to current lithium-ion batteries. However, the morphological instability of the lithium metal anode continues to remain a major bottleneck. Specifically, the formation of voids at the lithium/solid-electrolyte interface during stripping is a critical challenge as it leads to the loss of electrochemical contact and potential occurrences of internal short-circuit during a subsequent plating step. In this presentation, the coupled set of electrochemical/mechanical interactions governing the onset and growth of voids in the lithium metal anode will be discussed. The critical role of factors such as external pressure, self-diffusion kinetics, and the microstructure and mechanical properties of lithium on the void growth process will be analyzed. Further, this work will offer mechanistic insights into the evolution of reaction heterogeneity at the lithium/solid-electrolyte interface during plating and stripping, and correlate them to the underlying failure mechanisms in solid-state batteries.
High Energy Density Sulfide-Based All-Solid-State Batteries by Tailoring Electronic Conductivity within Composite Cathode
Authors: Shin Hyeon-ji , Kim Jun Tae , Han Da-Seul , Nam Kyung-Wan , Jung Hun-Gi
Published: December 2024

The sulfide-based all-solid-state batteries (ASSBs) has guaranteed having excellent safety by using non-combustible inorganic solid-electrolyte (SE). SE separator can transport Li ion selectively and there is no concentration gradient in theory, enabling fast charging. In addition, due to high ionic conductivity of sulfide-based SE comparable to liquid based electrolyte, high capacity and high energy density ASSBs of 5mAh cm-2 have been developed to a stage close to commercialization.

So far, among the many issues of ASSBs, the performance improvement has been achieved by focusing on interfacial deterioration issues. However, recent several studies have analyzed and identified the cause of inhomogeneous reaction in composite cathode, which lead to capacity degradation quickly. It had been confirmed that the inhomogeneous reaction was caused by not only loosely contact and isolated active materials but also restriction Li conductivity in nano-crystal boundaries of active materials, resulting in localizing overcharge-discharge and decreasing in capacity and rate capability. As one of intrinsic properties of ASSBs, the solid-solid contact induce the limitation of lithium ion mobility and it also triggered insufficient electronic conduction pathway increasing charge transfer resistance.

In order to develop high-energy density and high power ASSB, the ability of the conductivity for electron and ion must be balanced through the formation of a well-developed electronic percolating pathway. In this study, the inhomogeneous reactivity that can be maximized in thick electrodes is alleviated by improving the electron transfer path in the composite cathode. To uniformly transfer electrons in the composite cathode, we introduced argyrodite type SE coating with 2D conductive material under solvent environment. This approach is effective on forming a continuous electronic pathway for homogeneous reactivity as well as reduce SE oxidation by preventing direct contact between SE and cathode active material. As a result, we obtained a high initial capacity of 206 mAh g-1 using a single LiNi0.8Co0.1Mn0.1O2 cathode and SE coated with 2D conductive material, and confirmed that approximately 90% rapacity maintained after 200th cycle.
Effect of Size Distribution of Solid Electrolyte on Tortuosity of Ionic Conductivity
Authors: Yano Takeru , Hofer Moritz , Ohsaki Shuji , Nakamura Hideya , Watano Satoru , Inoue Gen , Michalowski Peter , Kwade Arno
Published: December 2024

Solid state batteries (SSBs) are expected to be the next-generation of batteries due to their high energy density and safety. To emphasize the battery performance of SSBs, it is crucial to analyze and design the electrode structure. The powder compression process is one of the most important processes for determining the battery structure. Powder compression is a molding method used to transform powders into solid and high-density compacts. The powder properties and compression conditions influence the packing structure and density of compacts. In this study, we elucidated the effect of the size distribution of a sulfide solid electrolyte on the ionic conductivity of pellets. The particle size distributions of lithium phosphorus sulfur chloride (LPSCl), a solid electrolyte with high plastic deformability, were prepared to evaluate its effect on the relative density and electrochemical properties. The average particle size of LPSCl was reduced through the milling process, and the resulting compacts were evaluated by impedance measurement after mixing raw and milled LPSCl with different mass fractions. The ionic conductivity of the compacts was found to be improved with the broadening of the particle size distribution of the solid electrolyte. Furthermore, the effect of the particle size distribution of the solid electrolyte on the electrode structure was also investigated numerically. The numerical simulations were performed in consideration of the actual particle size distribution to evaluate the void fraction and tortuosity of the electrodes. A discrete element method (DEM) can simulate the powder behavior by calculating the motion of individual particles based on Newton’s second law. Edinburgh elasto-plastic adhesive (EEPA) model, which can consider particle plasticity and cohesiveness, was applied as the contact force model. Particle plasticity parameter λ
p was calibrated based on force-displacement curves obtained by nanoindentation tests. The compression process was calculated assuming an infinite flat plate. Although the calculated relative densities agreed with the experimental trend, the values differed from the experimental values owing to the disregard of particle shape. In addition, tortuosity was evaluated by the shortest path algorithm using the powder bed obtained from the numerical analyses. An effective tortuosity was calculated by weighting the contributions of the conductive paths by its number of particles. The effective tortuosity also increased due to the higher number of particles generated during the LPSCl milling process. The combination of DEM analysis and the shortest path algorithm, taking into account grain boundary resistance, demonstrated that is was possible to correlate the electrode structure of the SSB with its electrochemical performance.
Low Potential Benzotriazole Derivatives As Negolytes for Nonaqueous Redox Flow Battery: Design, Synthesis and Electrochemical Investigations
Authors: Palani Sabhapathy , Munoz Sanchez Miguel , Sengupta Uddalak , Powers David C , Gurkan Burcu E
Published: December 2024

Nonaqueous redox flow batteries (NARFBs) are emerging as a promising technology due to their ability to achieve higher energy densities and voltages, thanks to the broad potential window of nonaqueous electrolytes (around −3 V vs. Fc/Fc+), compared to aqueous systems. A significant challenge in developing NARFBs is finding stable, redox-active molecules that can fully utilize the cathodic potential of non-aqueous solvents, particularly given the poor electrochemical cycling stability of radical anions formed at potentials below −2.0 V. Overcoming this issue is critical for the advancement and optimization of NARFBs technologies. In this study, we carefully engineered and synthesized benzotriazole derivatives as promising negolytes for NARFBs, aiming to achieve both low potential and steadfast stability. Electrochemical assessments underscored the critical role of solvent and supporting electrolyte selection in attaining stable and reversible electrochemical performance. Our findings illuminated that introducing an electron-donating group at the N2 nitrogen position in benzotriazole significantly increased the electron density. This modification led to a notable reduction in the potential and improved stability of the derivatives by stabilizing the anion radical form. We recorded redox potentials as low as −2.45 V vs. Ag/Ag+ (−2.55 V vs. Fc/Fc+), coupled with a high solubility of 3.5 M, indicating the potential for achieving substantial cell voltages when used with compatible posolytes. Density functional theory calculations unveiled a direct correlation between the position of the LUMO and the reduction potential, as well as between the HOMO-LUMO energy gap and the rate of electron transfer. By successfully regulating the electron density at the molecular level, we believe this study sheds light on constructing highly stable and low-potential redox molecules for NARFBs.
Enabling Two-Electron Redox Systems for Energy-Dense Organic-Based Flow Batteries
Authors: Kitamura An , Malapit Christian
Published: December 2024

Redox flow batteries (RFBs) have emerged as a promising grid-scale energy storage technology to meet increasing energy demands. In RFBs, the electroactive materials are in solution stored in external tanks. This separation of the electrode from the electroactive material allows them to be scalable for large-scale operation. Current RFBs use Vanadium as the active material (VRFB). Despite its ability to provide long-duration cycling, VRFBs are limited by the high cost of vanadium and low energy density. To address this issue, organic-based redox flow batteries (ORFB) have gained attention to replace Vanadium. Redox-active organic molecules (ROMs) based on abundant organic structures could reduce costs and offer the possibility to access greater energy densities. As the energy density is proportional to the number of electrons transferred per molecule, ROMs that display two redox-active behaviors can double the electron concentration and energy density. However, multi-electron ROMs are underexplored compared to one-electron systems due to their challenging discovery and synthesis. To advance the class of such systems, structurally simple and abundant dicarbonyl-based compounds were investigated as two-electron negative ROMs. N-Methylphthalimide (N-MePh), a 1,3-dicarbonyl compound, has previously been used as a one-electron ROM, but the instability of the dianion has inhibited its use as a two-electron ROM. A molecular engineering approach was taken to stabilize the dianion and enable two-electron capacity cycling of N-MePh derivatives. Additional dicarbonyl-based compounds are under further investigation to expand the library of multi-electron ROMs for ORFBs.

Figure 1
Effects of Electrolyte Composition on the Electrochemistry of Organic Mixed Conducting Polymer Electrodes
Authors: De La Fuente Duran Ana , Siemons Nicholas Daniel , Marks Adam , Magni Arianna , Salleo Alberto , Chueh William C. , Mefford Tyler
Published: December 2024

Organic mixed ionic-electronic conductors (OMIECs) are semiconducting conjugated polymers that can transport both electrons and ions throughout their bulk. This property is enabled by electrochemical ion-insertion redox reactions that co-dope the polymer with mobile ions and electrons (or holes). These redox and mixed conduction capabilities provide functionality for applications including organic batteries, actuators, and organic electrochemical transistors. These various applications are enabled by a few fundamental OMIEC redox processes that involve polymer-electrolyte and polymer-electrode interfaces as well as mobile ions and significant amounts of incorporated solvent. Understanding the role of electrolyte in changing these redox processes can enable improved performance across a variety of devices.

This work sets out to identify the role of electrolyte composition in changing the electrochemistry of a conjugated ladder polymer through a multi-faceted experimental and theoretical approach. We primarily focus our efforts on BBL, more formally called poly(benzimidazobenzophenanthroline). Using rotating disk electrochemistry, we find that electrolyte can cause a significant change in the voltage windows in which BBL is redox-active. Using operando UV-Vis and Raman spectroscopy measurements, we identify changes in BBL electrochemistry when operated in different electrolytes. To gain further insights about the redox mechanisms for this polymer, we use DFT to model our operando Raman data and principal component analysis to propose a charging mechanism that accounts for this electrolyte-dependent performance. Our results suggest that the accessible redox states of this polymer can dramatically change based on a modification of its local environment.
Improving the Battery Metrics of Commercial Hard Carbon through S-Doping for Sodium-Ion Batteries
Authors: Manna Sanchita , Puravankara Sreeraj
Published: December 2024

Hard carbon (HC) is now the leading choice for the anode in Sodium-ion Batteries (SIBs) because of its low operating voltage, high reversible capacity, and the wide range of inexpensive materials that may be used to synthesize it. The primary concern in commercial HCs is the initial Coulombic efficiency (ICE) and rate capability [1-2]. Hard carbon (HC) can exhibit a wide range of microstructures, morphologies, surface areas (including different types of pores), and porosities. These characteristics are determined by the carbon-rich material employed during synthesis and significantly impact the methods by which sodium ions are stored in HCs [3]. This study presents a novel structure of S-doped hard carbon derived from commercial HC. The sulfur-doped hard carbon material exhibits 67% ICE and maintains 94% of its capacity after undergoing 500 cycles at a rate of 300 mA/g (Fig.1). The sodium-ion storage mechanism of the S-doped HC material is analyzed using ex-situ Raman, XRD, SEM, EPR, and XPS techniques. These post-treated HC are compared with available commercial HC as anodes in sodium-ion batteries (SIBs) for a state-of-the-art evaluation of the battery metrics.

References:

A. Vasileiadis, Y. Li, Y. Lu, Y. S. Hu, and M. Wagemaker, ACS Appl. Energy Mater., 6, 127–140 (2023).

Nagmani, Manna, S., & Puravankara, S., Chemical Communications, 60(22), 3071-3074 (2024).

S. You, Q. Deng, Q. Zhang, K. Huang, and C. Yang, ACS Sustain. Chem. Eng., 11, 10590–10597 (2023).

Figure 1
Rechargeable Hydrogen Gas Batteries for Large-Scale Energy Storage
Authors: Chen Wei
Published: December 2024

Large-scale energy storage is of significance to the integration of renewable energy into electric grid. Despite the dominance of pumped hydroelectricity in the market of grid energy storage, it is limited by the suitable site selection and footprint impact. Rechargeable batteries show increasing interests in the large-scale energy storage. However, the challenging requirement of low-cost materials with long cycle and calendar life restricts most battery chemistries for use in the grid storage. Recently we developed a new generation of rechargeable hydrogen gas batteries by exploiting catalytic hydrogen evolution/oxidation reactions as the anode, which offers negligible overpotentials, high rates and stable electrochemical performance. In this talk, I will introduce some exciting rechargeable hydrogen gas battery chemistries, including novel nickel-hydrogen gas, proton-hydrogen gas, chlorine-hydrogen gas, and among others. The excellent stability and low cost of the rechargeable hydrogen gas batteries demonstrate attractive characteristics for large-scale energy storage.
LaAl3 Intermetallic Alloy Anode for Fluoride-Ion Battery
Authors: Sasano Shun , Ishikawa Ryo , Kawahara Kazuaki , Shibata Naoya , Ikuhara Yuichi
Published: December 2024

An all-solid-state fluoride-ion battery is one of the promising candidates for next-generation secondary batteries owing to its high energy density compared to a commercial lithium-ion battery [1]. While the practical capacities of cathodes have recently shown improvements in discharge capacities (up to 200 – 500 mAh g–1) [2], the capacities of anodes are still one order of magnitude smaller than that of cathodes, and moreover, their cycle stability are also very low [3]. It is therefore important to improve the electrochemical performance of the anodes in fluoride-ion batteries. Aluminum (Al) is one of the promising metals owing to the high theoretical capacity (2980 mAh g–1) and the low redox potential (–1.7 V vs. Pb/PbF2). However, there is no report on the practical use of Al because of the significantly low F– ion conductivity of AlF3 (10–11 S cm–1 at room temperature). To secure the low F– ion conductivity of AlF3, we explore the intermetallic alloy between Al and La because LaF3 shows a higher F– ion conductivity (10–8 S cm–1) than that of AlF3. Here, we show that LaAl3 reversibly delivers the high capacity with relatively small capacity fade [4].

LaAl3 intermetallic alloy was prepared from La with a purity of 99.9% and Al with a purity of 99.999% by arc melting, and then annealed at 950℃ for 336 h. The LaAl3 phase was confirmed by powder X-ray diffraction. To prepare the anode composites, the LaAl3 powders were mixed with La0.9Ba0.1F2.4 (solid electrolytes) and acetylene black (conductive aids) powders in the weight ratio of 3:6:1, using planetary ball mills with ZrO2 balls under a rotation speed of 100 rpm for 20 h. Using galvanostatic cycling, we performed charge/discharge tests of the all-solid-state fluoride-ion battery, where LaAl3 and PbF2 were used as anode and cathode active materials, respectively. The initial discharge and charge capacities are 445 mAh g–1 and 202 mAh g–1, respectively. While the 1st discharge curve shows a monotonous potential increment, the subsequent charge and discharge curves show stable potential plateaus at –2.0 V and –1.5 V. To elucidate the charge/discharge mechanism of LaAl3, we performed structural and chemical analysis of the 1st discharged and charged LaAl3, using scanning transmission electron microscopy (STEM) combined with electron energy-loss spectroscopy (EELS). We found that LaAl3 is decomposed into LaF3 and AlF3 nanocrystals in the initial discharge process. Detailed discussion will be given in this presentation.

Acknowledgements

This presentation is based on results obtained from a project, JPNP21006, commissioned by the New Energy and Industrial Technology Development Organization (NEDO).

References

[1] M.A. Reddy et al., J. Mater. Chem. 21 17059 (2011).

[2] K. Nakayama et al., J. Mater. Chem. A, 10, 3743 (2022).

[3] M.A. Nowroozi and O. Clemens, ACS Appl. Energy Mater., 1, 6626 (2018).

[4] S. Sasano et al., J Electrochem. Soc. 170 120523 (2023).
First-Principles Study of Layered Electrode Materials for Multivalent Batteries
Authors: Park Haesun , Kim Deahyun
Published: December 2024

Energy storage systems that efficiently shuttle multivalent cations such as calcium (Ca) or magnesium (Mg) have been increasingly spotlighted due to their potential for achieving high energy density at a lower cost. The advancement of these multivalent energy storage systems necessitates the exploration and development of electrode materials that not only offer high capacity but also ensure the reversible accommodation of multivalent cations. Recent studies on monovalent alkaline ions such as potassium and sodium, which exhibit a similar ionic radius to calcium, have demonstrated their capability for reversible intercalation into inorganic compounds with layered structures. This notable finding suggests a strong potential for the successful intercalation of divalent ions in analogous structures, thereby enhancing the versatility and efficiency of these energy storage systems.

In this context, we have employed first-principles calculations to systematically investigate and reveal that layered structures are conducive to topotactic intercalation of Ca or Mg, attributes characterized by favorable phase stability, electrochemical performance, cation mobility, and transition metal redox behavior. These layered materials, through our detailed computational analysis, show promise for the next generation of high-performance, cost-effective multivalent energy storage systems.
Vacancy-Driven Sodium Diffusion in Sodium Closo-Borohydride As Solid-State Electrolyte
Authors: Oh Jin An Sam , Meng Ying Shirley
Published: December 2024

Solid electrolyte is the cornerstone of the next-generation all-solid-state batteries. To realize the all-solid-state battery, the solid electrolyte must possess a high ionic conductivity and an electrochemical window that matches the electrode redox reaction potential. Recently, sodium closo-borohydrides have attracted significant attention for their high ionic conductivity and excellent reduction stability1,2. In this presentation, we will share our recent finding on the metastable nature of one of the sodium closo-borohydride chemistry using synchrotron X-ray diffraction and solid-state nuclear magnetic resonance spectroscopy. Additionally, we investigated the ions diffusion mechanism in the crystal structure that leads to high room-temperature ionic conductivity. Leveraging the high ionic conductivity, we realize an all-solid-state battery with high areal capacity and efficiency.

1Deysher, G., Oh, J. A. S., Chen, Y. T., Sayahpour, B., Ham, S. Y., Cheng, D., ... & Meng, Y. S. (2023). An Anode-Free Sodium All-Solid-State Battery.

2Oh, J. A. S., Deysher, G., Ridley, P., Chen, Y. T., Cheng, D., Cronk, A., ... & Meng, Y. S. (2023). High‐Performing All‐Solid‐State Sodium‐Ion Batteries Enabled by the Presodiation of Hard Carbon. Advanced Energy Materials, 13(26), 2300776.
Architecting Manganese Oxide Oxygen Reduction Electrocatalysts Adds New Function to Zinc–Air Cells
Authors: Rolison Debra R. , Long Jeffrey W. , Chervin Christopher N. , Ko Jesse S. , Parker Joseph F. , Hopkins Brandon J.
Published: December 2024

In aqueous alkaline electrolyte, why use platinum in the air cathode to electrocatalyze oxygen reduction (ORR) when the 2×2 tunnel polymorph of MnO2 (cryptomelane) is effective, more sustainable, and a lower cost catalyst? A polymorphic cousin, lamellar birnessite MnO2, also catalyzes ORR and is the morphology attained by sacrificially oxidizing the walls of carbon nanofoam papers (CNFPs) with permanganate thereby creating an architected catalyzed air cathode. Birnessite-painted CNFP (MnOx@CNFP) brings high areal capacity for pulse power through Mn4+/3+ redox-based capacitance, even while catalyzing ORR in primary zinc–air cells. The oxide spontaneously recovers the +4 charged state as residual molecular in the meso/macroporous electrode re-oxidizes the discharged +3 state. In powder-composite air cathodes, cryptomelane expressed as an ultraporous, covalently networked aerogel architecture sustains continuous high load demands in a primary zinc–air cell that the denser xerogel form of cryptomelane cannot. But in rechargeable zinc–air cells, manganese oxides are less effective electrocatalysts for oxygen evolution (OER), requiring high charging voltage that degrades the oxide coupled with parasitic oxidation reactions of electrolyte and carbon that limit cycle life. Formulating powder-composite air cathodes with cryptomelane aerogel and an OER electrocatalyst, such as Ni ferrite expressed as an aerogel, keeps charging voltage < 2 V while cryptomelane still dominates ORR catalysis for a higher discharge cell voltage. Versus a dendrite-suppressing zinc sponge anode, the cell using an air electrode formulated with two architected oxygen electrocatalysts delivers state-of-the-art low voltage hysteresis and power performance. The interdependent role catalytic activity and carbon stability play on cycle life point to the importance of cell metrics to rethink catalyst and electrode design. Preventing carbon corrosion, whether by replacing carbon with other electronic conduits or improving electrocatalyst activity, needs greater emphasis as a strategy for rechargeable zinc–air cells to achieve high total areal energy density.
Study of the Local and Average Structure of Vanadium Oxides As Potential Cathodes for Mg-Ion Batteries
Authors: Samanta Anwesa , Cabana Jordi
Published: December 2024

Being a divalent cation with the lowest mass, Mg2+ has garnered quite attention in recent times due to the high volumetric capacity of it’s batteries. Theoretical studies reveal that the combination of a Mg anode and a spinel oxide cathode would be able to surpass the current limits found in widely used Li-ion batteries Therefore, to design materials with high diffusion and reversible insertion capacity, a conclusive demonstration of the intercalation mechanism of Mg2+ into metal oxides, is required.

Among the numerous options for cathodes, vanadium oxides show evidence of the largest capability toward reversible intercalation of Mg ions. In particular, spinel-type MgV2O4 shows a capacity of 200 mAh/g, corresponding to the cycling of ~0.7 mol Mg2+ per mol of oxide, and layered α-V2O5 reaches 300 mAhg-1, intercalating 1 mol Mg2+ per mol of oxide. The extent and reversibility of these reactions were confirmed by elemental, redox and structural characterization in recent work [1,2]. This high capacity is only observed at 110°C and it is accompanied by a large hysteresis in potential during the electrochemical cycling. The push to overcome these bottlenecks demands a more comprehensive definition of the underlying mechanisms of reaction than is currently available.

Previous X-ray Diffraction (XRD) measurements conducted on the oxide indicated a loss of reflection intensity due to a loss in their crystallinity which makes structural characterization using typical diffraction techniques difficult. Through this work, we mainly make use of pair distribution function techniques to study the changes in the local structures of these oxides in both their pristine and charged state, to find out the local symmetry is being preserved even at the cycled state, thus giving new insights in further pushing the efficiency of multivalent battery materials.

Reference:

1. Hu, L., Jokisaari, J.R., Kwon, B.J., Yin, L., Kim, S., Park, H., Lapidus, S.H., Klie, R.F., Key, B., Zapol, P. and Ingram, B.J., 2020. High capacity for Mg2+ deintercalation in spinel vanadium oxide nanocrystals. ACS Energy Letters, 5(8), pp.2721-2727.

2. Yoo, H.D., Jokisaari, J.R., Yu, Y.S., Kwon, B.J., Hu, L., Kim, S., Han, S.D., Lopez, M., Lapidus, S.H., Nolis, G.M. and Ingram, B.J., 2019. Intercalation of magnesium into a layered vanadium oxide with high capacity. ACS Energy Letters, 4(7), pp.1528-1534.
Design and Performance of a Sodium and Mercury Low-Temperature Liquid Metal Battery with a NaSICON Solid-State Electrolyte for Large Scale Energy Storage
Authors: Kattelman Jake , Moon Jeremy , Chidambaram Dev
Published: December 2024

Liquid metal batteries (LMB) have the potential to be ideal grid-scale storage batteries; they maintain their performance and exhibit high efficiencies because they do not structurally degrade like lithium-ion batteries. While current commercial LMBs operate at temperatures above 500°C, low temperature LMBs are more attractive because they experience less corrosion of structural components and require less external heating for operation. In this work, we will detail a sodium – mercury battery with a NaSICON solid state electrolyte that operates at 110 °C. Described will be the manufacturing of the solid-state electrolyte, assembly of the full cell, and performance.
Tailoring Cathode Materials: Al2O3 Coating for Advanced Sodium-Ion Batteries
Authors: Banik Trapa , Bhattacharya Indranil , Soyoye Babatunde , Antony Dhason Mary Vinolisha
Published: December 2024

The attractive combination of sodium-ion battery's (SIB) homogeneous profusion in earth and LIB's identical intercalation chemistry makes it possible drop-in replacement for lithium-ion battery (LIB) technology in the ever-growing energy storage market. Layered transition metal oxide cathodes are the most sought-after for SIB cathodes because of their superior sodium storage capabilities, increased energy density, and straightforward synthesis process. However, these intercalation materials are prone to severe capacity decline and pose several safety concerns. In addition to safety concerns, several explanations of this capacity fading have been proposed, including structural instability, metal ion solubility in the electrolyte due to HF generation, and degradation of the electrolyte at higher cutoff voltages (>4.3 V). Metal oxide coatings are viable owing to their cost-effectiveness and ease of application. The inactivity of the metal during electrochemical reactions is attributed to its persistent valance state; consequently, cathodes adorned with such coatings experience a decline in ion conductivity. In this research, a thin layer of coating is employed upon titanium and vanadium doped sodium iron manganese oxide () via sol-gel process followed by a solid-state ball milling method in order to improve the rate capability and long term cyclic stability. The thickness and uniformity of the coating layer is verified from the SEM and EDS images. Furthermore, the XRD analysis is performed to see whether any modification has occurred in the cathode lattice due to the coating. Following that, the electrochemical performance of uncoated P2-electrodes is compared to that of coated P2- electrodes via electrochemical analyses such as galvanostatic charge-discharge test, CV and EIS which validate the efficacy of coating on ). This straightforward surface modulation technique will open up a potential route for the synthesis of superior cathode materials for sodium-ion batteries.