bluuebunny/crossref_metadata_2025 huggingface dataset:
(Invited) Grid Scale Energy Storage Poised for Success: Developing New Technologies, Finding New Value Propositions Towards Long Duration Energy Storage
Authors: Gyuk Imre
Published: September 2023

Energy storage (ES) has become one of the hottest topics to the world’s clean energy future. Research on materials and devices has made successful progress in reducing the cost of Li-ion systems and of several flow battery systems. However, safety, material sustainability, and other factors such as maintenance and decommissioning costs that affect the levelized cost of storage also need to be considered in developing a circular economy to enable reliable, resilient, and flexible electric grid.

ES in the United States (US) has become a resounding success. We have done well in short-duration energy storage, by developing viable business models, evaluation and planning tools, and so on. ES has achieved a great feat in frequency regulation, smoothing renewable energy, demand charge reduction, and substation upgrade deferrals. Going forward, energy storage of medium and long duration as well as short duration with further lower cost will be needed.

The presentation will give a high-level overview on the current state of DOE’s Office of Electricity (OE) supported energy storage technologies. Sodium-ion batteries, aqueous zinc batteries, and several new lines with earth abundant, inexpensive materials, and reliable supply chains and a wide industrial base will be covered. Reliability, safety, and representative examples of the successful deployment of OE technologies across multiple states in US will be touched.

As the return on investment is what really counts for the commercial success of energy storage applications, the presentation also will discuss several real cases of diverse monetized and unmonetized benefit streams from multi-megawatt deployments and how these assessments are needed for new technologies and longer duration applications.
(Invited) Recent Progress Towards Giga-Scale Sodium-Ion Batteries
Authors: Wessells Colin D
Published: September 2023

Ongoing lithium-ion minerals supply chain volatility has driven price increases and supply shortages, and motivates the development and commercialization of alternative cell chemistries not dependent on those minerals.1-2 Among these alternative chemistries, sodium-ion cells offer promise due to the abundance and low cost of both sodium salts and typical electrode active species such as iron and manganese.2-3 Among sodium-ion electrode systems, Prussian blue analogues offer unique performance advantages including high C-rate charge and discharge, long cycle life, and thermal stability.4-6 Natron Energy has commercialized a unique sodium-ion cell in which each of the anode and cathode active materials are Prussian blue analogues. Products based on these cells are capable of full discharge at up to 60C, full recharge at up to 20C, and operate for tens of thousands of cycles without risk of thermal runaway. However, their energy density is limited by relatively low electrode specific capacities and cell voltage. This presentation will introduce the key materials science concepts that make Prussian blues a commercially viable materials system, as well as those that limit product performance, manufacturability, and the resulting applicable markets. In addition, Natron’s recent progress towards mass manufacturing of cells based on these materials will be summarized. This presentation will conclude with an overview of the key open scientific questions that must be answered for cost effective, giga-factory scale manufacturing of sodium-ion cells to become a reality.

References:

“2H 2021 Battery Metals Outlook: The Long Road to Recovery,” BloombergNEF, December 16, 2021.

“Technology Radar: Sodium-Ion Batteries,” BloombergNEF, October 27, 2022.

“2021 roadmap for sodium-ion batteries,” Nuria Tabia-Ruiz et al, 2021 J. Phys. Energy 3 031503.

“Assessment of the first commercial Prussian blue based sodium-ion battery,” He, Minglong, et al, J. Power Sources 548 (2022) 232036.

“Nickel Hexacyanoferrate Nanoparticle Electrodes for Aqueous Sodium and Potassium Ion Batteries,” Wessells, C.D., et al, Nano Letters 11 (2011) 5421-5425.

“Monovalent manganese based anodes and co-solvent electrolyte for stable low-cost high-rate sodium-ion batteries,” Firouzi, A., et al, Nat. Commun. 9 (2018) 861.
(Invited) Development of Commercial-Scale High Energy Density Aqueous Zinc Manganese Dioxide Alkaline Batteries for Long Duration Storage
Authors: Banerjee Sanjoy
Published: September 2023

Alkaline zinc manganese dioxide batteries are attractive for grid related energy storage applications but have been limited to relatively low utilization of the active materials to assure good cycling performance. Zinc anodes tend to deteriorate due to shape change, passivation, and dendrite formation during charge/discharge cycles. Manganese dioxide cathodes also deteriorate due to formation of inactive crystalline polymorphs during cycling. Recent work using additives in both the anodes and the cathodes has mitigated these issues and enabled access of much higher active material utilization levels, up to 50% of the two-electron capacity of the zinc and over 75% of the two-electron capacity of the manganese dioxide electrodes. Commercial-scale cylindrical (jelly roll) cells of 150 to 200 Wh, particularly suitable for long duration energy storage with discharge periods from a day to a week, have been manufactured on a pilot line. Their performance and various deployments will be discussed indicating areas where future developments would be of importance.
(Invited) Deeply Rechargeable Zinc Anodes for High-Energy Rechargeable Aqueous Batteries
Authors: Liu Nian
Published: September 2023

Zinc-based aqueous batteries are promising alternative to many mainstream battery technologies today, due to the superior safety and broad availability of raw materials. However, existing zinc anodes suffer from either poor cycle life or low utilization in both neutral and alkaline aqueous electrolytes. Passivation, dissolution, and hydrogen evolution are three main reasons for irreversibility of zinc anodes in alkaline electrolytes, which limits the rechargeability and usable energy density. In this talk, I will present our recent works on using nanoscale material design to overcome passivation, dissolution, and hydrogen evolution issues of zinc anode, towards a deeply rechargeable zinc-based battery. I will also introduce the battery-gas chromatography quantitative analysis, as well as in situ microscopy methodologies we have developed, to quantify gas evolution side reaction, as well as visualize the reaction on electrodes during operation.
Zinc Anodes with Electrodeposited Ionomer Protection Layer for Rechargeable Zinc-Air Batteries
Authors: Vacandio Florence , Knauth Philippe , Kwarteng Papa-kwakye , Pasquini Luca , Syahputra Suanto
Published: September 2023

Metal air batteries are assembled from a metal anode and a porous cathode in a suitable electrolyte. They combine the design of fuel cells and conventional batteries and have been demonstrated to have large theoretical energy densities higher compared to devices based on Li-ion chemistry, due to the ability to use air at the cathode and to exchange two electrons per zinc atom. ZAB represent a safe, environmentally benign, affordable and simple way to store and deliver electrical energy for a wide variety of devices. However, research efforts are necessary to increase the efficiency of rechargeable ZAB and mitigate obnoxious occurrences that decrease the number of charge-discharge cycles such as zinc dendrite formation, cathode degradation and alkaline electrolyte carbonation.

The protection of zinc metal anodes in zinc-air batteries (ZAB) is an efficient way to reduce corrosion and Zn dendrite formation and improve cyclability and overall battery efficiency. The extent of improvement depends on the type and thickness of the protective layer.

In this work, we explore an advanced coating of the zinc anode by anion-conducting poly(N-vinylbenzyl, N,N,N trimethylammonium) chloride (PVBTMA) that is electropolymerized directly on the zinc metal. The Zn deposition in presence of quaternary ammonium salts and polyelectrolytes was recently studied to improve the cyclability. The major advances foreseen by this approach are excellent qualities of the metal/ionomer interface, due to the in-situ deposition process, improving the corrosion protection and the selective anion permeability; furthermore, the chosen ionomer presents a high stiffness and strength to resist the formation of zinc dendrites, due to the stiff polystyrene backbone. Moreover, the presence of a polyelectrolyte separator facilitates device miniaturization. The zinc anode protection layer was observed by optical microscopy and scanning electron microscopy (Figure : SEM micrographs of Zn pellet with PVBTMA layer: a) from 0.01 M precursor solution, b) and c) from 0.1 M precursor solution) .and the wettability of the ionomer-coated zinc surface was investigated by contact angle measurements.

The resulting ZAB battery with PVBTMA anode coating is analyzed in terms of cyclability in alkaline electrolyte and solid-state configuration using a Whatman paper separator.

The goal is to pair metal-free electrode materials with appreciable catalytic activity for oxygen reduction and evolution with a zinc anode that has a protection layer against dendrite formation to maximize efficiency.

Figure 1
Nature of Zinc-Derived Dendrite and Its Suppression in Mildly Acidic Aqueous Zinc-Ion Battery
Authors: Kim Sun , Kim Hee Jae , Heo Kwang , Lim Jae-Hong , Yashiro Hitoshi , Myung Seung-Taek
Published: September 2023

Aqueous zinc-ion batteries (ZIBs) are attractive in energy storage due to the use of aqueous electrolytes that ensures safety and ease of handling all parts in air. However, catastrophic zinc dendritic growth on zinc metal anode impedes their practical application. Herein, we introduce Zn3(PO4)3·4H2O (ZP)-coated zinc metal anode, to effectively suppress the dendrite growth and first elucidate the chemical state of dendrite that is composed of metallic Zn0, ZnO, and Zn(OH)2. Significant improvement is observed for the ZP-coated zinc metal symmetric cell. Operando synchrotron tomography demonstrates that the ZP-coating layer ensures uniform deposition of zinc-derived compounds by the ZP layer that scarifies itself through decomposition to P2O5, Zn0, and Zn(OH)2. Meanwhile, the local reaction between P2O5 and H2O reproduces H3PO4, which provides a condition to reproduce Zn3(PO4)2·4H2O via a reaction between H3PO4 and metallic Zn on the Zn metal anode. This cyclic re-formation of Zn3(PO4)2·4H2O progressively prevents the dendritic for long-term even at high rates. The compatibility is verified in NaV3O8||ZP-coated zinc anode cell over 1000 cycles. As a result, this finding presents a practical way for uniform deposition of Zn that can be applicable to aqueous and non-aqueous ZIBs.
(Invited) Confirmation of Na-O-Li Configuration for P2-Type Cathode Materials
Authors: Myung Seung-Taek
Published: September 2023

Oxygen-redox-based cathode materials for sodium-ion batteries (SIBs) have attracted considerable attention in recent years owing to their possibility of delivering additional capacity in the high-voltage region. However, they still suffer from not only fast capacity fading but also poor rate capability. Herein, we introduce P2-Na0.75[Li0.15Ni0.15Mn0.7]O2, an oxygen-redox-based layered oxide cathode material for SIBs. The effect of Ni doping on the electrochemical performance was investigated by comparison with Ni-free P2-Na0.67[Li0.22Mn0.78]O2. The Na0.75[Li0.15Ni0.15Mn0.7]O2 delivered a specific capacity of ~160 mAh g-1 in the voltage region of 1.5–4.6 V at 0.1C in Na cells. Combined experiments (galvanostatic cycling, neutron powder diffraction (NPD), X-ray absorption spectroscopy (XANES), X-ray photoelectron spectroscopy (XPS), and nuclear magnetic resonance (7Li NMR)) and theoretical studies (density functional theory, DFT calculations) confirmed that Ni substitution not only increases the operating voltage and decreases voltage hysteresis but also improves the cycling stability by reducing Li migration from transition metal (TM) to Na layers. This research demonstrates the effect of Li and Ni co-doping in P2-type layered materials and suggests a new strategy of using Mn-rich cathode materials via oxygen redox with optimization of doping elements for SIBs.
Activating Mn Redox for Boosting Performance Enabled by Highly Oxidized Ru in a P2-Type Cathode Material for Sodium-Ion Batteries
Authors: Yu Jun Ho , Yu Jun Ho
Published: September 2023

To overcome the inherent limitations of sodium-ion batteries (SIBs) such as relatively low energy density and operating voltage compared to lithium-ion batteries (LIBs), Oxygen redox chemistry is considered to realizing a high-performance battery system. However, oxygen redox commonly accompanied problems such as sluggish kinetics, O2 gas loss, and irreversible structural rearrangement with voltage hysteresis. Herein, we suggest a new model that deviates from the tendency of relying on oxygen redox reaction to realize high capacity. A deep investigation of Na0.6Mg0.2Mn0.8O2 (NMM) and Na0.6Mg0.2Ru0.2Mn0.6O2 (NMRM) is conducted by various analysis tools for the comparison. The highly oxidized Ru5+ lowers the Mn oxidation state in the structure without the Jahn-Teller effect. It drives the increased participation of Mn in the overall electrochemical reaction and the charge compensation by oxygen redox reaction is mostly replaced by the Mn3+/Mn4+ redox pair. A strong covalence of Ru stabilizes the structure and prevents cation migration from TM to Na slap. As a result, even though the specific weight increased, practical capacity was improved by maximizing the participation of Na+ ions, and we confirm that cyclability and rate capability also improved.
Internal Magnetic Fields for Improved Cyclability in Aqueous Zn-Br2 Static Batteries
Authors: Sheelam Anjaiah , Glasco Dalton Lee , Bell Jeffrey Gordon
Published: September 2023

Owing to their high safety and low-cost, aqueous zince-bromine batteries (AZBBs) are envisioned as being highly applicable in both portable and stationary energy storage. The highly reversible Zn/Zn2+ (-0.76 V vs. RHE) and Br-/Br2 (1.08 V vs. RHE) redox couples have been employed in Zn-Br2 flow batteries (1.84 V vs. RHE), although widespread implementation has not been realized. This is largely because parasitic losses in overall battery performance rapidly occur due to i) dendritic growth of Zn deposits during the repetitive discharge process, leading to internal short circuits and ii) the cross-diffusion of highly soluble Br- (Br3
-) ions causing severe self-discharge and reduced cycle life. Common approaches to mitigate these problems include electrode engineering and incorporating additives and ion-selective membranes into the system for improving cycle life and coulombic efficiency. This talk will highlight the benefits of fabricating an aqueous Zn-Br2 static battery with internally contained magnetic fields, (~ 30, 40, 50 and 60 mT) at the anode and cathode by incorporating 1 mm thick Nd permanent magnets. Here we show that moderate internal magnetic fields are capable of simultaneously mitigating dendrite growth while drastically reducing cross-diffusion, leading to enhanced cycle life and improved energy and voltage efficiency. Operando UV-Vis spectroscopy, scanning electro microscopy (SEM), and electrochemical methods (electrochemical impedance spectroscopy and cyclic voltammetry) were used to to rationalize the effect of magnetic fields on the performance and cyclability of AZBBs.
In Situ Mechanical Measurements in Vanadium Pentoxide Cathodes for Aqueous Zinc-Ion Batteries during Battery Cycling
Authors: Marckx Bret A , Capraz Omer Ozgur Özgür
Published: September 2023

Aqueous rechargeable zinc-ion batteries (AZIBs) are currently gaining traction as a potential successor to lithium-ion batteries for use in large-scale, stationary energy storage applications due to their inherent safety, low environmental impact, and low-cost. Recent advances have made breakthroughs in these anode and electrolyte stability; however, cathode development still lags preventing the commercial use of AZIBs. Vanadium pentoxide (V2O5) shows promise as a cathode material due to its low cost, environmental friendliness, and high specific capacity versus zinc (in excess of 400 mAh/g)1. V2O5 exhibits a single layer crystal structure which provides a large number of theoretical storage sites2. However, charge storage mechanisms and driving force behind the capacity fade in V2O5 are not well known yet. The lack of understanding surrounding insertion and storage mechanisms of zinc ions into V2O5 cathodes must be addressed to progress toward commercial viability.

In this study, we aim to conduct in-operando stress and stress measurements in V2O5 during battery cycling. Curvature interferometry and digital image correlation techniques will be employed for in operando stress and strain measurements, respectively the composite V2O5 cathode will consist of a 7:2:1 ratio of active material, super P, and PVDF binder. By combining stress and strain measurements, coupled with spectroscopy studies, our goal is to identify the how interfacial stress and structural strains play a role on the charge storage mechanisms in V2O5.

References:

Xu, X. et al. Enhanced charge transfer and reaction kinetics of vanadium pentoxide for zinc storage via nitrogen interstitial doping. CEJ, vol. 451, p. 3, (2023). DOI: 10.1016/j.cej.2022.138770

Tang, B. et al. Issues and opportunities facing aqueous zinc-ion batteries. Energy Environ. Sci., Issue 11, pp. 3288-3304 (2019). DOI: 10.1039/C9EE02526J
High Performance Zinc-Based Anodes for Aqueous Zinc Batteries
Authors: Fayette Matthew , Li Xiaolin , Reed David
Published: September 2023

In the past thirty years, there has been significant development in the search for alternative energy sources such as secondary battery systems. Zinc (fourth-most mined material) has attracted much attention due to its abundance, low-cost, and recyclability. Moreover, as zinc-based batteries can be manufactured with aqueous-based electrolytes that benefits from many advantages of Zn anode, such as low redox protentional (-0.76V vs SHE), high theoretical capacity (820mAh/g), and enhanced safety. These features allow for high applicability in large-scale stationary energy storage system. Zinc-based batteries (MnO2/Zinc) have been previously commercialized and are one of the dominant technologies in the primary battery market. However, the alkaline MnO2/Zn battery is not currently considered re-chargeable due to the formation of zinc-dendrites, passivation of Zn metal, and cathode poisoning. In contrast to the alkaline system, the mild acidic system does not suffer from zinc passivation as there is negligible generation of zinc oxide/zinc hydroxide.

In this work, we report a proof-of concept work where electrodeposited zinc-based anodes (zinc and zinc-alloys) are used in mild acidic aqueous electrolyte. The study provides a comparison of commercial zinc foil, and electrodeposited zinc/zinc-alloy. The anodes are further analyzed structurally through X-ray diffraction and scanning electron microscopy. To evaluate the feasibility of each anode. further electrochemical characterization was carried out in coin cells as symmetric and full cells. The electrodeposited zinc-based anodes exhibit low electrode polarization (~0.030-0.045V), and more stable cycling performance at 10 mA cm-2 compared to commercial zinc foil. Furthermore, full cells with an electrodeposited zinc or zinc-alloy anode, DTT cathode, in 2M ZnSO4 delivered comparable capacities but higher stability compared to commercial zinc. Consequently, this work points toward a further development for anode materials in rechargeable aqueous zinc batteries for scalable applications.
Carbon-Coated Sodium Vanadium Phosphate Nanocomposites as Efficient Cathode Materials for Sodium-Ion Batteries and Capacitors
Authors: Liao Wan-Ling , Hung Tai-Feng
Published: September 2023

Sodium vanadium phosphate (Na3V2(PO4)3) with continuous carbon-coating (NVP/C) has been regarded as one of the most promising cathode materials for sodium-ion batteries (SIBs) owing to the three-dimensional sodium superionic conductor (NASICON) structure for fast sodium-ion migrations, high theoretical energy density (ca. 400 Wh/ kg), and good thermal stability (450°C). In this study, NVP/C nanoparticles (NPs) were successfully synthesized by employing ascorbic acid as the reductant and carbon source simultaneously, followed by calcination at 750°C in an argon atmosphere. The NVP/C NPs possessed great crystallinity, high purity, size of 100-200 nm, coated carbon layer of 5-10 nm, and carbon amounts of 8.5 wt. % were confirmed through the X-ray diffractometer, transmission electron microscope, and thermogravimetric analyzer, respectively. The remarkable reversible capacity (75 mAh/g at 0.1 C), rate capability (62 mAh/g at 2 C), and capacity retention (~100% after 1,000 cycles at 1 C) were delivered from the NVP/C half-cell. Encouraged by these impressive results, the asymmetric sodium-ion capacitors (SICs) consisted of the NVP/C cathode, free-standing hydrogel-derived hierarchical porous activated carbon (H-HPAC) anode, and organic electrolyte were also assembled to explore the electrochemical performances. As revealed, excellent rate capabilities were also achieved, i.e., 44 mAh/g at 0.45 A/gNVP and 28 mAh/g at 4.5 A/gNVP. Accordingly, the NVP/C NPs synthesized in the present study are reasonably believed to serve as potential cathode materials for SIBs and SICs.

Figure 1
Flash Pyrolyzed Coal Char for Sodium Ion Battery Anodes
Authors: Moon Jaron V , Karimi Zahra , Prlina Alex , Ginkel Chanel Van , Eddings Eric , Warren Roseanne
Published: September 2023

Present day lithium ion batteries face challenges regarding the sustainability, cost, and natural resource availability of their components. Sodium has been shown to be a complementary energy storage material, providing usable volumetric energy density. In designing sodium ion batteries (SIBs), hard carbon is used at the anode in place of graphite, due to the necessary micro domain structure needed to store sodium ions. Coal char is a low cost material and viable source of hard carbon. The use of coal char in SIBs also provides a high value, secondary use pathway for the abundant char component of coal.

In this work, flash pyrolyzation is explored as a novel approach for coal char synthesis for SIB anodes using a Utah local bituminous coal. During flash pyrolyzation, char is heated in a drop-tube furnace at 1000 oC/s vs. the traditional slow pyrolyzation approach where char is heated at 20 oC/min. Flash pyrolyzed (FP) char has a surface structure that is vastly different in comparison to the slow pyrolyzed (SP) char (Figure 1.), larger d-spacing (FP d-spacing = 0.379 nm, SP d-spacing = 0.364 nm) and a smaller closed micropore diameter (FP micropore = 1.52 nm, SP micropore = 1.91 nm), as concluded from X-ray diffraction (XRD) and small angle X-ray scattering (SAXS) analysis, respectively.

The SIB performance of FP char vs. SP char is tested and compared in ether-based and ester-based electrolytes. FP char performs better as a SIB anode than SP char in both electrolytes. Additionally, both char anodes achieve higher reversible capacity and better initial coulombic efficiencies (ICE) in an ether-based vs. ester-based electrolyte. When FP char is combined with an ether-based electrolyte, a 10th cycle reversible capacity of 109.4 mAh/g is achieved, whereas a SP char with an ester-based electrolyte cell has a 10th cycle reversible capacity of 72.5 mAh/g, when both cells are cycled at 50 mA/g (sodium metal half-cells). FP ether cells also perform with an initial coulombic efficiency (ICE) of 64%, but SP ester cells only show an ICE value of 52%. The enhanced electrochemical performance of the FP cells is attributed to differences in surface/bulk structure due to the high heating rate. The improvement in char anode performance in ether-based cells is likely due to the formation of a thinner solid-electrolyte interphase and/or improved sodiation due to an ether-based electrolyte.

Figure 1
Interface Controls Large-Volume Change Anodes Pulverization
Authors: Kim Namhyung , Xu Yaobin , Gwalani Bharat , Cai Jiyu , Fayette Matthew , Omenya Fredrick , Li Guosheng , Gao Peiyuan , Reed David , Chen Zonghai , Wang Chongmin , Li Xiaolin
Published: September 2023

Micron sized alloys have been considered as the most attractive candidates for advanced lithium or sodium ion battery anodes due to their high capacity, cost effectiveness, and ease of mass production. However, their large volume variation during (de)alloying reaction with Li or Na ions causes severe mechanical degradation of anode materials, resulting in particle pulverization and loss of electrical interparticle contact. In addition, this substantial volumetric fluctuation leads to newly exposed anode surface to electrolyte and instability of solid-electrolyte interphase (SEI), which can bring about continuously formation of SEI layers. To mitigate the large volume change issues of micron sized alloys, various approaches have been studied such as introducing various electrolytes and additives for stabilizing the SEI layers. However, these modified SEI layers are still not enough to suppress the large volume fluctuation of micron sized alloys.

Here, we demonstrate that the effect of interface between electrolyte and anode surface on anode pulverization. With micron sized alloying anodes for sodium-ion batteries (Bi and Sn), we observed substantially different pulverization behavior as a choice of electrolyte solvents leading to different anode-electrolyte interface. This different interface reactivity between solvents has a big impact on not only pulverization behavior of alloying anodes but also formation and growth of SEI layers on the surface of anode. Thus, the electrochemical performances of the alloying anodes also can be influenced by its interface characteristics. We thoroughly analyzed the effect of interface of alloying anode from electrode-level to nanoscale by various characterization tools such as Scanning electron microscopy (SEM), X-ray computed tomography (X-ray CT), X-ray photoelectron spectroscopy (XPS), Atom probe tomography (APT), and cryo-transmission electron microscopy (TEM). Moreover, we clarified the mechanism of the interface reaction and pulverization pathway by theoretical simulations. We believe this study can help researchers to understand the degradation behavior of large volume change alloy anodes.
Transition Metal-Doped SnO2 As Versatile Battery Electrode Material
Authors: Birrozzi Adele , Lenzer Anja , Asenbauer Jakob , Mullaliu Angelo , Bresser Dominic
Published: September 2023

Tin oxide-based materials have been intensively investigated as alternative anodes for lithium-ion batteries due to their high specific capacity, environmental friendliness, non-toxicity, and ease of handling. However, the initial formation of Li2O upon lithiation is essentially irreversible, which has a severe effect on the first cycle Coulombic efficiency and the reversibly achievable capacity in general.[1]It has been shown that the incorporation of transition metal dopants can address this issue, as it enables the reversible formation and reformation of Li2O.[2] The choice of the dopant, however, plays a critical role for the long-term cycling stability, rate capability, and eventual energy density of the resulting lithium-ion cells.[3]

While there have been intensive studies published already on the effect of different dopants for Li-ion battery applications, targeting an optimized combination for achieving enhanced cycling performance[3] and an in-depth understanding of the reaction mechanism,[4,5] the investigation as Na-ion battery active material has not been reported so far. In fact, our results show that the reaction mechanism is fundamentally different, while the incorporation of transition metal dopants is still favorable for the eventual charge storage via sodium cations. The resulting insights into the de-/sodiation mechanism are anticipated to enable the development of further enhanced electrode active materials for sodium-ion batteries and, thus, support the recent success of this alternative battery technology.

Reference
s

[1] D. Bresser, S. Passerini, B. Scrosati, Energy Environ. Sci.
2016, 9, 3348.

[2] Y. Ma, Y. Ma, G. Giuli, T. Diemant, R. J. Behm, D. Geiger, U. Kaiser, U. Ulissi, S. Passerini, D. Bresser, Sustain. Energy Fuels
2018, 2, 2601.

[3] A. Birrozzi, J. Asenbauer, T. E. Ashton, A. R. Groves, D. Geiger, U. Kaiser, J. A. Darr, D. Bresser, Batter. Supercaps
2020, 3, 284.

[4] J. Asenbauer, A. Wirsching, M. Lang, S. Indris, T. Eisenmann, A. Mullaliu, A. Birrozzi, A. Hoefling, D. Geiger, U. Kaiser, R. Schuster, D. Bresser, Adv. Sustain. Syst.
2022, 6, 2200102.

[5] A. Birrozzi, A. Mullaliu, T. Eisenmann, J. Asenbauer, T. Diemant, D. Geiger, U. Kaiser, D. Oliveira de Souza, T. E. Ashton, A. R. Groves, J. A. Darr, S. Passerini, D. Bresser, Inorganics
2022, 10, 46.
(Best Student Presentation) Extending the NaCl-AlCl3 Phase Diagram to Enable Low-Cost, Long-Duration Na-Al Batteries for the Grid
Authors: Weller Jon Mark , Li Minyuan Miller , Polikarpov Eugenia , Han Kee Sung , Li Guosheng , Kidner Neil , Patel Anant , Jung Keeyoung
Published: September 2023

Achieving deep grid decarbonization via intermittent renewable power sources requires extensive grid-scale energy storage technologies to deliver stable power during periods of low generation. Doing so at scale and at low cost further adds to this challenge, as current solutions generally rely on geographically limited solutions such as pumped hydro storage, or costly battery chemistries focusing primarily on Li-ion technologies. As an alternative, battery systems based on lower cost materials such as sodium offer an attractive alternative for low-cost, scalable, and non-geographically limited electrochemical energy storage.

This work combines an abundant and inexpensive molten sodium metal anode with a cost-effective aluminum cathode to provide a proof-of-concept alternative for grid-scale energy storage. Building on prior work utilizing the high reversibility of the neutral sodium chloroaluminate (NaAlCl4) molten salt electrolyte commonly used for classic molten sodium batteries, this work demonstrates greater capacity utilization of the NaCl-AlCl3 binary system by ‘overcharging’ this Na-Al battery to form an acidic chloroaluminate catholyte, NaAl2Cl7. Leveraging the reaction between NaAlCl4 and NaAl2Cl7 in conjunction with that between Al/NaCl and NaAlCl4 advantageously utilizes the majority of Na available in the cathode for capacity, in addition to providing a higher discharge voltage (~ 2 V compared to ~ 1.6 V for the NaAlCl4 reaction), thereby adding ~ 119 Wh kg-1 additional specific energy, on top of the 493 Wh kg-1 theoretical specific energy of the neutral Na-Al battery reaction between Al/NaCl and NaAlCl4.

Fundamental aspects of the acidic chloroaluminate reaction are investigated, showing that cells using only the acidic reaction are able to cycle for hundreds of cycles. The acidic reaction between NaAlCl4 and NaAl2Cl7 occurs via a solution-phase reaction, unlike the two-phase neutral reaction between NaCl/Al and NaAlCl4, and we confirm via Raman and NMR spectroscopies that complete conversion to NaAl2Cl7 occurs at end of charge. Na-Al batteries utilizing both reactions demonstrate high areal capacity (~ 46 mAh cm-2) and excellent reversibility. Enabled by the rapid mass transfer and solid-liquid reaction mechanism of the chloroaluminate catholyte, a higher areal capacity cell with ~ 132 mAh cm-2 is demonstrated, allowing a discharge duration of 28.2 h, implying that this Na-Al battery chemistry may be suitable for long-duration energy storage for grid applications. Finally, the raw active materials cost of this battery is estimated to be only ~ $7 kWh-1, which is promising for enabling low-cost renewable power utilization for the grid.

Figure 1
Development and Characterization of New Cathode Materials for Sodium-Metal Chloride Batteries
Authors: D'Urso Claudia , Frusteri Leone , Samperi Mario , Leonardi Gianluca
Published: September 2023

Solid metal halides are used as active cathode ingredients in the case of Na-NiCl2 batteries that require a fused secondary electrolyte, sodium tetrachloraluminate (NaAlCl4), to facilitate the movement of the Na+ ion into the cathode. The sodium-nickel chloride (Na - NiCl2) battery has been extensively investigated as a promising system for large-scale energy storage applications. The growth of Ni and NaCl particles in the cathodes is one of the most important factors that degrade the performance of the Na-NiCl2 battery. The larger the particles of active ingredients contained in the cathode, the smaller the active surface available for the electrochemical reaction. Therefore, the growth of Ni and NaCl particles can lead to an increase in cell polarization resulting from the reduced active area. A higher current density, a higher state of charge (SOC) at the end of the charge (EOC) and a lower Ni / NaCl ratio are the main parameters that result in the rapid growth of Ni particles.

In light of these problems, cathode and chemistry Nano-materials with recognized and well-documented electrochemical functions have been studied and manufactured to simultaneously improve battery performance and develop less expensive and more performing, sustainable and environmentally friendly materials. Starting from the well-known cathodic material (Na-NiCl2), the new electrolytic materials have been prepared on the replacement of nickel with iron (10-90%substitution of Nichel with Iron), to obtain a new material with potential advantages compared to current battery technologies; for example, (1) lower cost of cathode material compared to the state of the art as well as (2) choices of cheaper materials (stainless steels could be used for cell components, including cathode current collectors and cell housings).

The study on the particle size of the cathode and the physico-chemical characterization of the cathode was carried out in the test cell using, where possible, the GITT method (galvanostatic technique of intermittent titration). Furthermore, the impact of temperature on the different cathode compositions of the positive electrode was being studied. Especially the optimum operating temperature is an important parameter of the active material.
A Multiscale Hollow Spherical LATP Active Filler Improves Conductivity and Mechanical Strength in Composite Solid Electrolytes
Authors: Howell Benjamin R , Patil Bebi H , Gallaway Joshua W
Published: September 2023

The performance of composite solid electrolytes (CSEs) composed of poly(ethylene oxide) and ceramic oxide-type solid electrolyte fillers has been shown to be highly dependent on the available surface area of filler inside of the composite. This is due to the formation of new transport pathways in the polymer-ceramic interphase, a region some tens of nanometers between the bulk polymer and ceramic surface. The small volume of this interphase relative to the size of traditional particles presents a design problem: Using micron-scale filler particles, a nm-thick interphase can never occupy a meaningful volume fraction of the composite. Thus, nanoparticles are often used in CSEs. However, the inevitable agglomeration of nanoparticles prevents a continuous interphase from forming even in the best dispersion conditions. Therefore, efforts to explore and exploit this synergistic transport mechanism have so far relied on careful, slow, and expensive methods designed to yield a continuous polymer-ceramic interphase between electrodes, e.g., cast nanowires, infiltrated 3D-structures, or templating.

In this work we report a ceramic solid electrolyte, Li1.3Al0.3Ti1.7(PO4)3 or LATP, with a multiscale hollow spherical microstructure, designed to maximize the available continuous interphase volume in the composite. The hollow spherical structure is achieved by synthesizing LATP particles onto 10-15 μm carbon spheres, then subsequently pyrolyzing the carbon to achieve micron-scale hollow spheres composed of nano-scale LATP particles. This structure effectively prevents the bulk agglomeration of individual LATP particles, while still allowing for long, continuous interphase pathways. Importantly, the non-directionality of the filler means that the manufacture of the films remains simple.

The hollow spherical microstructure of the filler had significantly enhanced the room temperature conductivity of the composite solid electrolyte, to 1.64 x 10-4 S/cm – the highest reported for an LATP-containing CSE with micron-scale filler particles. The mechanical properties, thermal stability, and electrochemical stability of the composite solid electrolyte were also significantly enhanced. This approach is a promising method to exploiting the synergistic transport in composite solid electrolytes while maintaining their excellent manufacturability.
Usage of Co-Solvent for Fabricating the Composite Cathode for Sulfide-Based All-Solid-State Lithium Batteries
Authors: Lee Hanjo , Hong Seung-Bo , Lee Young-Jun , Kim Dong-Won
Published: September 2023

In recent decades, lithium-ion batteries (LIBs) have been widely used in electric vehicles and large-scale energy storage systems. However, current LIBs using the flammable organic electrolytes have a safety issue. Therefore, all-solid-state lithium batteries (ASSLBs) with enhanced safety and high energy density are in the spotlight. Among many solid electrolytes, sulfide-based solid electrolytes with high ion conductivity and ductile property are the most promising. In order to develop the ASSLBs, the composite cathode with high mass loading is imperative, which can be fabricated by the wet process suitable for mass production. Polar solvents can disperse a binder with polar groups well, but it may cause severe dissolution of sulfide solid electrolytes in the composite cathode. Therefore, we tried to use co-solvent that can disperse a polymer binder well and prevent the dissolution of sulfide solid electrolyte. Cycling performance of ASSLBs employing the wet-type composite cathode was evaluated and will be reported.
Study of Li-Si Alloy Composition for Anode Materials in Sulfide-Based All-Solid-State-Batteries
Authors: Kim Min Ju , Kang Sung , Lim Hyung-Tae
Published: September 2023

Lithium alloys are promising anode materials with high specific capacity for all-solid-state-batteries (ASSBs). In this study, ASSBs were fabricated by consisting of Li-Si alloy anode, sulfide electrolytes and sulfur composite cathode.

During discharge-charge cycles, changes in polarization resistance in the anode and cathode were separately traced using three-electrode system of an embedded Indium reference electrode in ASSBs. As de-alloying and alloying in Li-Si anode, Li distribution and phase changes were investigated using x-ray diffraction, optical microscopy and Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMs). A half-cell was fabricated by using Indium foil as a counter electrode to study the Li ion diffusion coefficient in Galvanostatic Intermittent Titration Technique(GITT). It is observed that Li composition (22:5 ~ 1:1) in Li-Si alloy anode affected the chemo-mechanical stability and volume expansion behavior in ASSBs, which were associated with the redox behavior of sulfide solid electrolyte.
Iron-Based Cathode Material for Lithium Ions and Metal Batteries
Authors: Adams Jada I. , Crockem Ayssia N. , Masafwa Kutemwa , Meda Lamartine
Published: September 2023

Metal oxyfluoride conversion cathodes are very attractive as high energy material due to their high redox reactions because of the high electronegativity of fluorine atom. It has been demonstrated that the rutile structure of FeOF has been obtained, but there are only a few reports about the cubic phase of FeOF. In this study, we are demonstrated a cubic phase of FeOF can be obtained after charging and discharging a mixture of ball milled LiF/FeO at 750 rpm for 12 hours. Although, X-ray diffraction did not show the presence of Fe+3 in the starting material, X-ray-photo electron spectroscopy revealed the presence of Fe+3 suboxides. Excellent cycling stability was obtained and a cell was cycled at 50 mA/g in liquid electrolyte. We also demonstrate long-cycle stability for over 200 cycles at 40 °C when a solid electrolyte was used. The solid electrolyte was embedded with a cross-linked composite polymer electrolyte to improve transport of lithium ion inside the cathode. The electrochemical properties of both the lithium ion and the lithium metal properties will be compared.

Figure 1
Unlocking Li Superionic Conductivity in Fcc-Type Oxides via Face-Sharing Configurations
Authors: Chen Yu , Ouyang Bin , Ceder Gerbrand
Published: September 2023

Li metal oxides with a face-centered cubic (fcc) anion sublattice have been generally excluded from the search for solid-state Li superionic conductors, as the structural framework is thought to be unfavorable for Li superionic conduction. Herein, we demonstrate a face-sharing design strategy that turns fcc-type oxides into superionic conductors, with a Li ionic conductivity of 3.38×10−4 S cm−1 at room temperature and a low migration barrier of 255 meV. The combination of experimental and theoretical investigations reveals that the high Li-ion conductivity is attributed to the facile Li-ion diffusion pathways comprising the face-sharing polyhedra. Our work unlocks the great potential of designing Li superionic conductors in a prototypical structural framework with vast chemical flexibility, providing a fertile ground for discovering new solid-state electrolytes for all-solid-state batteries.
Atomic-Scale Engineering of Grain Boundary Chemistry and Potential for Li-Garnet Solid-State Electrolytes
Authors: Chu Hyunwon , Defferriere Thomas , Kim Kunjoong , Paik Haemin , Tuller Harry L. , Rupp Jennifer L.M.
Published: September 2023

With increasing demands to replace flammable liquid electrolytes, solid-state electrolytes have sparked interests both in academic and industrial sectors. In particular, Li-garnet LLZO (Li7La3Zr2O12) exhibits outstanding electrical, chemical, and mechanical properties. Despite the promise, LLZO suffers from the formation of lithium (Li) dendrites at high current operations, thereby limiting the safety and performance of garnet-based solid-state batteries. Li metal nucleation and growth reportedly initiate and grow along the locality of grain boundaries (GBs) in such polycrystalline electrolytes, due either to low ionic or high electronic conductivity of the boundaries. However, limited understanding yet exists on the origins of the local GB conductivity mismatch. The mechanistic understanding should be an important prerequisite to develop engineering strategies of the failing GB interfaces. In this work, we first apply grain boundary core-space charge layer model to understand the basis of Li metal nucleation at GBs. Grain boundary core of LLZO is modeled to have excess negative charge potential, leading to the subsequent Li ionic carrier depletion and electronic carrier accumulation in the adjacent space charge layers. The carrier concentration variations then drive the local electronic conductivity surge and detrimental Li metal nucleation at the GBs. Both electrochemical and microscopic characterization techniques are employed to investigate the atomic-level composition and space charge potential at the GBs. This understanding offers us new strategies for controlling Li nucleation. First, sintering atmosphere is selectively chosen to reduce the potential barrier by suppressing intrinsic defect accumulation at the GB core. Second, an aliovalent dopant, with net-positive charge, is introduced to segregate to GB and mitigate the negative core potential. Both approaches are shown effective in lowering the electronic conductivity and to impede Li metal penetration. We successfully achieve critical current densities (CCD) of ~ 1 mA cm-2,a two-fold increase over prior reports. Our theoretical understanding and the engineering approaches will aid in interpreting the failure origin of the garnet electrolytes, and provide a blueprint on how to engineer GBs for improved safety and performance of all-solid-state Li metal batteries.
High Throughput Studies of Doped Li-La-Zr-O Garnet Solid Electrolytes
Authors: Anderson Ethan , Jonderian Antranik , McCalla Eric
Published: September 2023

Lithium lanthanum zirconium oxide (LLZO) is a leading candidate for solid Li-batteries due to its high lithium-ion conductivity, stability in air and against Li metal, and compatibility with high-voltage cathodes.1,2 Despite significant research being done, our understanding of LLZO is limited by the relatively small number of compositions which have been studied; both in the larger Li-La-Zr-O system and in the doped cubic LLZO system, which can accommodate an extremely wide range of dopants.3To study this large number of compositions, we have applied a high-throughput methodology for synthesizing, characterizing, and testing sets of 64 LLZO electrolytes at the mg-scale. We employ a citrate sol-gel synthesis method whereby reagent solutions are dispensed across a well-plate to give a composition gradient. After drying and calcining the gels, the resulting powders are pelleted and then sintered at the desired temperature. High-throughput characterization techniques utilized include powder X-ray diffraction, impedance spectroscopy, DC polarization, and electrochemical stability window testing.

Using our methodology, we have recently studied over 700 samples to produce a full phase stability diagram for the Li-La-Zr-O pseudoternary system.4 We found there is significant solubility of Li in the La2Zr2O7 pyrochlore structure, and that both cubic and tetragonal undoped LLZO appearing throughout the system have similarly poor bulk conductivities. This previous study again emphasizes the key role dopants play in LLZO. Herein, our methodology is applied to a comprehensive doping study where 60 different dopants are evaluated under identical synthesis conditions to allow for a thorough understanding of dopant effects on structure, ionic conductivity, electronic conductivity, and electrochemical stability window. Our samples achieve high conductivities over 1 mS/cm and relative densities above 90% with our combinatorial synthesis. Dopant content is optimized for each promising dopant to compare best-case results and correlate performance with structural properties like lattice parameters and density. Since comparing dopants in the literature is often difficult due to varying synthesis methods, this systematic work is essential in rational design of these electrolytes.

1.Q. Liu, et al., J. Power Sources
2018, 389, 120-134.

2.T. Thompson, et al., ACS Energy Letters
2017, 2, 462-468.

3.F. Zheng, et al., J. Power Sources
2018, 389, 198-213.

4.E. Anderson et al., DOI:10.1016/j.ssi.2022.116087.