Kelsey B. Hatzell

High Resolution Image Download MS PowerPoint Slide Bipolar membranes (BPMs) enable electrochemical systems that operate across large pH gradients; however, high-current operation is often limited by voltage losses whose origins remain difficult to resolve in membrane−electrode assemblies. Here, we combine electrochemical impedance spectroscopy with distribution of relaxation times (EIS–DRT) analysis and operando synchrotron X-ray diffraction to examine interfacial polarization, membrane hydration, and transport in commercial and synthesized BPMs. EIS–DRT isolates the BPM-associated interfacial contribution and shows that the commercial BPM exhibits larger water-dissociation-associated overpotentials than the synthesized BPM. Operando hydration mapping shows that both membranes retain water at the bipolar junction during high-current operation, while anode-adjacent hydration gradients are more pronounced in the commercial membrane. These results indicate that high-current voltage losses are not governed by junction water starvation alone but by coupled interfacial polarization and transport resistances.

High Resolution Image Download MS PowerPoint Slide Electrolyte composition, concentration, and structure can affect reaction kinetics, ion transport, and heat generation during operation. In liquid electrolyte systems, the properties of ion–solvent and ion–ion interactions strongly affect thermodynamics and electrochemistry. The change in total entropy of the electrolyte when one mole of an ion is added to an electrolyte at a constant temperature and pressure is known as the partial molar entropy of ion solvation and describes broadly how the solvation environment changes with the addition or removal of an ion. Herein, we measure the partial molar entropies of lithium-ion solvation in solid-state systems using potentiometric temperature coefficient measurements. For solid-state systems, we measure positive partial molar entropies of lithium-ion solvation of 43.3 J mol –1 K –1 for Li 6 PS 5 Cl and 26.4 J mol –1 K –1 for Li 6.5 La 3 Zr 1.5 T 0.5 O 12 . In contrast, the liquid electrolyte 1 M LiPF 6 in 1:1 vol % EC:DEC exhibits a negative partial molar entropy of −76.0 J mol –1 K –1 . A one-dimensional analytical model is developed to elucidate how the temperature coefficient is influenced by the multiple interfaces formed when an inorganic single-ion conductor is combined with a binary liquid electrolyte, providing a unified framework for understanding the partial molar entropies of ion solvation across a wide range of electrochemical systems.

E nergy resilience depends on secure and reliable supplies of the critical minerals, metals, and elements that power modern energy technologies.This need is driving renewed research in separations science, materials processing, recovery technologies, and AI-enabled discovery and automation.People often lump "critical minerals", "critical metals", and "critical elements" together, but each term refers to something slightly different.Critical minerals generally refer to non-fuel minerals that are both essential to manufacturing and at risk of supply chain disruptions.In such a way, critical minerals are a policy term used by government agencies to identify minerals or elements that are strategically important for energy technologies.Critical elements are basic chemical building blocks whose reliance on limited or complex processing infrastructure makes them vulnerable to supply disruptions. 1,2Criticality describes how important a material is to national priorities, and how vulnerable its supply chain is to disruption.As new energy, data, and manufacturing technologies emerge, the list of critical elements changes too, with new materials becoming important as demand grows.Researchers, engineers, and entrepreneurs are working across the critical minerals supply chain to identify new deposits, develop cleaner extraction methods, recover valuable elements from mine waste, and design energy technologies that use fewer scarce inputs. 1,3Yet, the central challenge is not mining alone.It is increasingly a material processing and recycling challenge: how to transform ores, mine waste, manufacturing scrap, electronic waste, and end-of-life products into the high-purity materials or components required for modern energy technologies. 3s demand grows for batteries, solar panels, and data centers, waste valorization and resource recovery are becoming increasingly important to the energy landscape and to the research

Electrochemical energy storage technologies (such as batteries and fuel cells) are vital for powering space devices. There has been tremendous progress in developing various batteries to meet different power demands in both stationary and transporation applications. From rovers to space suits, batteries are ubiquitous in space missions. Space applications however expose batteries to extreme environments which can cause capacity degradation. This review, discusses a range of secondary batteries including traditionally Ag‐Zn/Ni‐based batteries to lithium‐ion batteries and their use applications for space. The battery degradation mechanisms related to electrodes and electrolytes are examined via the lens of: (1) pressure, (2) radiation, (3) gravity, (4) magnetic field, (5) low temperature, and (6) high temperature. Recent improvements that tackle those challenges which are feasible for space applications are discussed. Based on the analysis of external operating environments and literature, we compared different secondary battery technologies’ properties and their resistances to those external environments and offered perspectives on the road forward.

High Resolution Image Download MS PowerPoint Slide The electrochemical reduction of CO 2 (CO 2 RR) is a potentially scalable approach for converting captured carbon dioxide into value-added products. Conventional gas-phase electrolysis systems can suffer from carbonate crossover, which limits the efficiency of the system. Liquid-phase (bi)carbonate electrolysis using bipolar membrane electrode assemblies (BPM-MEA) has emerged as a promising alternative. The interposer layer, a porous mass-transport material between the BPM and the catalyst, is an essential component of the MEA, as it allows evolved CO 2 to reach the catalyst surface for reaction. In the absence of this layer, evolved CO 2 generated by the pH swing process at the BPM can be converted back into (bi)carbonate (CO 2 recapture) due to the high bulk pH. Thus, clear design guidelines are needed to maximize CO 2 conversion, minimize CO 2 recapture in the catholyte, and improve energy efficiency. Here, the transport properties of the interposer are systematically characterized by X-ray tomography and symmetric-cell impedance spectroscopy to quantify porosity, tortuosity, and the resulting MacMullin number. We then examine the correlation between these material properties and the electrolyzer performance. We focus on characterizing two commercial porous membrane filters, mixed cellulose ester (MCE) and poly(ether sulfone) (PES).

Large-scale battery manufacturing requires understanding the fundamental principles of materials and interfaces and relies on advanced techniques for detailed interrogation. Despite advancements in the industrial scale production and their associated quality control tools, challenges such as electrode heterogeneity, internal defects, and large-scale material waste (e.g., scrap) can hamper manufacturing. Synchrotron X-ray characterization techniques offer spatial, temporal, and chemical resolution that can provide diagnostic insights for metrology across various manufacturing steps. This review examines the use of synchrotron tools to advance understanding of key steps in the battery manufacturing process. Recent examples demonstrate how synchrotron methods resolve manufacturing challenges and uncover degradation pathways that are otherwise inaccessible. Future directions for advancing battery manufacturing emphasize collaboration between academia and industry through the use of synchrotron X-ray techniques.

Phyllosilicates Phyllosilicates, abundant layered clay minerals, are reimagined as scalable and cost-effective candidates for advanced membrane technologies. This work highlights their tunable interlayer properties, enabling molecular-scale separations for applications in water purification, resource recovery, and energy systems. The cover illustrates the dynamic interplay of natural materials and engineered structures, symbolizing the transformative potential of phyllosilicate membranes. More details can be found in the Review Article by Seth B. Darling and co-workers (DOI: 10.1002/admi.202500510).

This study investigates lithium plating texture in anode-free solid-state batteries using synchrotron-based X-ray diffraction. Conventional methods are limited by lithium’s low electron density and softness, which hinders direct interrogation in anode-free solid-state batteries. Results reveal that lithium plating texture is influenced by temperature and current density. Under mild conditions, lithium exhibited a ⟨110⟩ fiber texture. However, higher current densities and elevated temperatures led to a more randomized orientation, suggesting a dependence on plating conditions. The results highlight how the operating and processing conditions for lithium metal can influence the texture of lithium metal and reversible operation.

Sodium-ion batteries (SIBs) are promising alternatives to lithium-ion batteries (LIBs) for low-temperature applications, owing to sodium’s lower desolvation energy compared to lithium. The crystal structure of the cathode active material determines the kinetics and transport properties of the cathode and can have a significant influence on the low temperature operation of SIBs. In this study, the performance of sodium layered (Na 2/3 Fe 1/2 Mn 1/2 O 2 , or NFMO) and channel-type cathodes (Na 0.44 MnO 2 , or NMO) at varying temperatures is investigated through electrochemical cycling, cyclic voltammetry, and electrochemical impedance spectroscopy. NMO, although having a lower initial capacity, demonstrates better capacity retention and more stable charge transfer kinetics at low temperatures. The lattice changes and relatively stable phases correlate with the electrochemical data, suggesting superior performance of channel-type NMO at lower temperatures. This indicates that the channel-type sodium cathode structure is more suitable for applications demanding stable performance at low-temperature conditions.

LIMNO

A bipolar membrane electrolyzer coupling bicarbonate electrolysis with formaldehyde oxidation directly produces syngas (H 2 : CO = 1) at 1.7 V and 200 mA cm −2 with 200% combined Faradaic efficiency.

High-throughput, low-cost manufacturing, and optimization of solid electrolytes are necessary for the adoption of solid-state batteries. In this work, garnet-type Li 7 La 3 Zr 2 O 12 (LLZO) with different aliovalent dopants, T a Z r ·, A l L i · ·, and G a L i · ·, have been ultrafast-sintered with different temperature ramping rates. The densification behavior, phases, their evolution, and surface chemistry of different LLZO have been investigated and linked to their electrochemical performances. It has been shown that LLZO with T a Z r · dopant demonstrates the highest garnet phase purity and overall best electrochemical performances, and ultrafast sintering further improves densification, ionic conductivity, and electrochemical stability. On the other hand, LLZO doped with A l L i · · and G a L i · · are reaching higher cubic phase purities and ionic conductivities via conventional sintering, indicating undesirable dopant migration and segregation during the ultrafast sintering process. These findings provide insights into the manufacturing of solid electrolyte materials.

Abstract Cylindrical 18650 cells are widely used in electric vehicles and space applications, where exposure to extreme temperature fluctuations is common. Repeated exposure to freezing and thawing cycles may accelerate electrode‐level degradation due to the associated temperature fluctuations. This study investigates the electrochemical and structural degradation of 18650 lithium‐ion batteries (LIB) subjected to more than 1000 cycles at 1C and 4C rates with periodic freeze‐thaw cycles. Using synchrotron‐based X‐ray computed tomography (XCT) and virtual unrolling techniques, it is found that freeze‐thaw cells cycled at 4C exhibited greater structural damage, including jelly roll buckling and electrode delamination, than regular cells cycled at 4C, while 1C cycled cells showed good freeze‐thaw resistance. This diagnostic framework offers a powerful approach to uncovering these hidden degradation pathways and informing more resilient battery designs for extreme use scenarios such as rovers or devices in space, where a high C‐rate is often required with extreme temperature swings between night and day.

This study investigates lithium plating texture in anode-free solid-state batteries using a synchrotron-based X-ray diffraction. Conventional methods are limited by lithium’s low electron density and softness, which hinders direct interrogation in anode-free solid-state batteries. Results reveal that lithium plating texture is influenced by temperature and current density. Under mild conditions, lithium exhibited a <textless110>fiber texture. However, higher current densities and elevated temperatures led to a more randomized orientation, suggesting a dependence on plating conditions. The results highlight how the operating and processing conditions for lithium metal can influence the texture of lithium metal and reversible operation.

Large-scale battery manufacturing requires understanding the fundamental principles of materials and interfaces and relies on advanced techniques for detailed interrogation. Despite advancements in the industrial scale production and their associated quality control tools, challenges such as electrode heterogeneity, internal defects, and large-scale material waste (e.g. scrap) can hamper manufacturing. Synchrotron X-ray characterization techniques offer spatial, temporal, chemical resolution that can provide diagnostic insights into for metrology across various manufacturing steps. This review examines the use of synchrotron tools to advance understanding of key steps in the battery manufacturing process. Recent examples demonstrate how synchrotron methods resolve manufacturing challenges and uncover degradation pathways that are otherwise inaccessible. Future directions for advancing battery manufacturing emphasize collaboration between academia and industry through the use of synchrotron X-ray techniques.

Abstract Membrane technologies have made critical advances in resource recovery, water purification, and energy systems. However, it is difficult to systematically tune properties of traditional polymer membranes, and researchers have struggled to deliver challenging, advanced separations using these platforms. In recent years, membranes based on 2D materials have drawn attention for molecular‐scale separations due to their unique properties, most notably their tunable nanoscale interlayer properties. Among the diverse family of 2D materials, phyllosilicates, a broad class of naturally abundant clay minerals, offer significant advantages in cost and scalability over synthetic 2D materials, positioning them as promising candidates for advanced membrane technologies. Their inherent structural and chemical properties, strategies for tailoring selective transport pathways, and recent advancements across applications including ion separation, water treatment, and energy conversion are discussed. Finally, key challenges and opportunities are outlined to guide future research in leveraging phyllosilicate membranes for high‐performance separation technologies.

Membrane technologies can enhance the efficiency and selectivity of chemical separations in energy-water systems. Advanced characterization tools are critical for discerning separation mechanisms, revealing degradation processes, and designing novel materials and material systems for new and emerging challenges. The pursuit of next-generation membranes for water and energy applications requires understanding phenomena at the molecular scale, mesoscale, and macroscale. This perspective highlights advanced characterization techniques for elucidating and enhancing membrane performance, while addressing fundamental trade-offs involved in characterizing membranes under realistic conditions.

We demonstrate an electrochemical syngas production platform that couples bicarbonate electrolysis with formaldehyde oxidation in a bipolar membrane electrode assembly. This strategy doubles syngas (CO + H2) throughput compared to conventional CO2 electrolysis by generating CO at the cathode and H2 at the anode. The system achieves a full-cell voltage of 1.7 V while operating at an industrially relevant current density of 200 mA cm-2. The system maintained a combined Faradaic efficiency of 200% over 8 hours. The process produces gas with a 1:1 H2:CO ratio, aligning with downstream requirements for Fischer-Tropsch synthesis. We further investigated how Cu anode active sites and electrolyte composition affect formaldehyde oxidation activity. Our integrated electrolytic system reduces levelized energy by 46% to 61% relative to conventional electrochemical syngas production platforms.

Separation membranes are critical for a range of processes, including but not limited to water desalination, chemical and fuel production, and recycling and recovery applications. Fundamentally, there are intrinsic trade-offs between permeability and selectivity. Local water organization and content can impact membrane structure (short- and long-range) in laminar transition metal carbide (MXene) membranes and impact selective ion permeation. Intercalation of chaotropic cesium (Cs[Formula: see text]) ions within the layers reduces the water content in the membrane and at the surface which cannot be found in the intercalation of other ions. Additionally, 3D imaging using focused ion beam scanning electron microscopy showed fewer defects in the Cs-MXene membrane, due to reduced local water content, leading to more efficient ion sieving. X-ray diffraction and density functional theory calculations on the nanochannel structure demonstrated that the chaotropic ion results in the smallest nanochannel size and induces a stronger resistance to water-induced nanochannel swelling. With a narrower nanochannel, the Cs-MXene membrane limits ion transport pathways, resulting in more selective transport of lithium over other metal cations, as evidenced in both experiment and molecular dynamics simulations. Our findings highlight the potential for controlling the structural organization of 2D MXene membranes to enable on-demand transport of ions for diverse applications.

Membrane nanofiltration is an attractive strategy for the selective recovery of high-demand metals from wastewater and brine. Effective sieving of ions in aqueous environments will require precise control over membranes’ nanochannel size and chemistry. Ti 3 C 2 T x MXene is an environmentally stable 2D material that can be processed into laminar membranes containing nanoscale interlayer spaces. The MXene interlayer environment depends on the ion species and amount of water intercalated between MXene sheets, and it is the major factor governing permeation and selectivity through MXene membranes. Coordinated ion–ion and ion-interlayer dynamics in the presence of complex mixtures can impact ion permeability and selectivity. Herein, we observe strong competitive effects between different cations (Li +, Na +, and Ca 2+ ) in binary mixtures, resulting in reduced selectivity when compared with single-salt permeability ratios. X-ray diffraction, molecular dynamics, and density functional theory simulations support the conclusion that cations with stronger attraction to MXene flakes can preferentially occupy the MXene nanochannels and hinder other ions via charge or size exclusion. Elucidation of ion transport behavior in MXene under complex conditions will allow for more rational design of efficient ion-sieving membranes.

Solid-state batteries can offer higher energy density and improved safety compared to lithium ion batteries, which use flammable liquid electrolytes. Increasing the ratio of cathode active materials in composite cathodes enhances the energy density and reduces manufacturing costs. Changes in the ratio of cathode active materials alter the microstructure and chemo-mechanical response of a cathode during operation. Understanding the relationship between composition, microstructure, and chemo-mechanical interactions is critical for optimizing solid-state cathodes. In this study, we engineered composite cathodes with varying ratios of LiNi 0.8 Co 0.1 Mn 0.1 O 2 and Li 6 PS 5 Cl to systematically investigate the role of microstructural evolution in long-term chemo-mechanical transformations. Chemo-mechanical stresses resulting from the volume changes of the cathode active materials led to degradation mechanisms, such as fracture and interfacial delamination. Active material fracture and delamination led to underutilization of active material and significant capacity decay during cycling. Coatings that suppress active material-active material interactions during cycling may aid in suppressing the generation of local stress hotspots.

Structural heterogeneity in solid-state batteries can impact the material utilization and fracture mechanisms. Crystallographically oriented LiCoO 2 film cathodes serve as a model electrode system for exploring how void distribution contributes to stress relief and buildup during cycling. Real- and reciprocal-space operando and ex situ synchrotron-based experiments are utilized to understand structural changes across multiple length scales that contribute to stress generation and fracture. Nanotomography uncovers a depth-dependent porosity variation in the pristine electrode and highlights the preferential fracture in regions of lower porosity during delithiation. Energy-dispersive X-ray diffraction and three-dimensional (3D) X-ray absorption near-edge spectroscopy (XANES) reveal the underutilization of cathode material in these regions. 3D XANES also confirms preferential delithiation near the subgrain boundaries. Chemo-mechanical modeling coupled with site-specific mechanical characterization demonstrates how stress accumulation in dense regions of the electrode leads to fracture and underutilization of active material. Our findings reveal the importance of material design to alleviate stress in small-volume changing cathodes.

Solid-state batteries unlock possibilities for using energy-dense anodes such as lithium metal while addressing key degradation challenges. However, unresolved issues at the material and cell levels have hindered their commercialization, including variability in mechanical control and testing methodologies, a limited understanding of material behavior under operating conditions, and performance and design gaps between cells for benchtop testing and cells for advanced characterization. This perspective highlights the current state-of-the-art in testing and characterizing solid-state batteries, focusing on mechanical monitoring and controls, benchtop diagnosis and characterization techniques, and advanced operando synchrotron imaging. We emphasize the need for uniform experimental standards, scalable and practical battery cell designs to match commercial operating conditions, and integrated approaches to design advanced in situ and operando experiments to reflect realistic battery operating conditions.

Lithium-reservoir-free solid-state batteries can fail due to electrical shorting as a result of fracture and lithium metal filament formation. Mechanical stress at the solid electrolyte surface can induce fractures, which promote lithium filament growth. This stress arises from both electrochemical sources, due to lithium electrodeposition, and mechanical sources, such as external stack pressure. Solid electrolyte surface roughness and the applied stack pressure together affect stress development. This study combines electrochemical experiments, 3D synchrotron imaging, and mesoscale modeling to explore how stack pressure influences failure mechanisms in lithium free solid-state batteries. At low stack pressure, irregular lithium plating and the resulting high local current density drive failure. At higher stack pressure, uniform lithium plating is favored; however, notch-like features in the surface of the solid electrolyte experience high tensile stress, leading to fractures that cause premature short-circuiting.

Anode-free solid-state batteries contain no active material at the negative electrode in the as-manufactured state, yielding high energy densities for use in long-range electric vehicles. The mechanisms governing charge–discharge cycling of anode-free batteries are largely controlled by electro-chemo-mechanical phenomena at solid–solid interfaces, and there are important mechanistic differences when compared with conventional lithium-excess batteries. This Perspective provides an overview of the factors governing lithium nucleation, growth, stripping and cycling in anode-free solid-state batteries, including mechanical deformation of lithium, the chemical and mechanical properties of the current collector, microstructural effects, and stripping dynamics. Pathways for engineering interfaces to maximize performance and extend battery lifetime are discussed. We end with critical research questions to pursue, including understanding behaviour at low stack pressure, tailoring interphase growth, and engineering current collectors and interlayers. Anode-free batteries contain no active material at the negative electrode when manufactured, and this can enable them to have high energy density. This Perspective presents a critical overview of the mechanisms governing the behaviour of anode-free solid-state batteries and provides guidance to improve this type of battery.

Alkali metal anodes hold great promise for high-energy-density batteries for grid-scale applications.

Sodium–potassium (NaK) liquid metal anodes address interfacial challenges in sodium solid-state batteries by eliminating solid–solid contact issues of solid Na anodes.

Abstract Lithium reservoir‐free solid‐state batteries (SSBs) can potentially be energy‐dense alternatives to conventional lithium‐ion batteries. However, controlling the morphology and organization of lithium metal at a current collector remains a challenge and hampers the cycle lifetime of these types of batteries. Porous interlayers have the potential to guide uniform lithium plating and improve electrochemical performance. Factors such as stack pressure, interlayer composition, current density, and interlayer mechanical properties all influence lithium electrode kinetics. This study explores how these kinetic factors impact lithium movement through a porous silver–carbon (Ag‐C) interlayer, lithium electrodeposits morphology, and electrochemical performance. Silver nanoparticles in interlayer can facilitate the lithium movement and induce internal stress which contributes to void formation which impedes the lithium flow. Decreasing pore sizes in the interlayer can lead to creep enhancement and preferential formation of lithium metal at the current collector. Porosity‐driven creep enhancement is correlated with the formation of denser and uniform electrodes which enable greater reversible operation at lower pressures.

Zero-excess solid state lithium metal batteries are considered the next-generation battery system recognized for their high volumetric energy density and improved safety. However, the non-uniform plating behavior of lithium metal against the current collector leads to poor coulombic efficiency and lithium dendrite formation [1]. Thus, it is essential to understand and quantify the plating behaviors to optimize the system. The texture, or crystallographic orientation, of lithium metal can be used to evaluate the morphology of lithium metal within batteries [2]. In liquid batteries, a strong {110} texture has been correlated with a denser and dendrite-free morphology [2], which can lead to a better coulombic efficiency [3]. However, it is currently not understood how the crystallographic orientation is affected by the presence of hydrostatic stress which is common in zero-excess solid-state batteries. The lack of knowledge is in part because accessing buried solid-solid interfaces is challenging and even more challenging when considering the volatile nature of lithium metal. In this study, we addressed the challenge by adopting synchrotron-based X-ray pole figure measurements [4]. Both synchrotron-based and lab-based X-ray pole figure measurements were utilized to reveal the texture evolution of lithium metal understand various conditions such as hydrostatic stress and temperature. By combining texture measurement with electrochemistry, we deconvoluted the impact of accumulated capacity, temperature, and current density on the quality of plated lithium metal. Understanding the impact of these factors will enable better control of operating conditions to achieve a more uniform and dendrite free lithium deposition, thereby ensuring longer-lasting and more stable zero-excess solid-state lithium metal batteries. References: [1] Christian Heubner, Sebastian Maletti, Henry Auer, Juliane Hüttl, Karsten Voigt, Oliver Lohrberg, Kristian Nikolowski, Mareike Partsch, and Alexander Michaelis. From Lithium-Metal toward Anode-Free Solid-State Batteries: Current Developments, Issues, and Challenges. Adv. Func. Mater . 2021 , 31 (51), 2106608. [2] Shi, Feifei, Allen Pei, Arturas Vailionis, Jin Xie, Bofei Liu, Jie Zhao, Yongji Gong, and Yi Cui. "Strong texturing of lithium metal in batteries." Proceedings of the National Academy of Sciences 114, no. 46 (2017): 12138. [3] Hu, Xitao, Yao Gao, Yongming Sun, Zhen Hou, Yufeng Luo, Danni Wang, Jiangpeng Wang, Biao Zhang, Zijian Zheng, and Quan Li. "Preserving the Li {110} Texture to Achieve Long Cycle Life in Li Metal Electrode at High Rates." Advanced Functional Materials 34, no. 11 (2024): 2307404. [4] Wenk, H-R., and S. Grigull. "Synchrotron texture analysis with area detectors." Journal of applied crystallography 36, no. 4 (2003): 1040-1049.

Growing demands for electric vehicles motivate the need for energy-dense battery technologies that can enable enhanced driving ranges on a single charge [1]. Zero-excess-lithium solid-state batteries operate with no excess lithium at the anode, instead fully cycling all the lithium within the cell during each cycle. Removing excess lithium significantly increases the specific and volumetric energy density, improves battery safety, and reduces manufacturing costs [2]. However, zero-excess-lithium solid-state batteries suffer from poor coulombic efficiency and lithium dendrite formation [3] resulting from non-uniform lithium deposition onto the anodic current collector [4]. Optical microscopy is a promising operando technique for examining the electro-chemo-mechanics of lithium nucleation and growth during lithium deposition in a zero-excess-lithium solid-state battery [4]. In this work, we investigate the lithium nucleation and growth behavior on a current collector substrate using a custom cell conducive to operando optical microscopy. The transparent components of the cell allow for direct, real-time observation of lithium plating behavior. In particular, quantifying the dynamic in-plane lithium growth as a function of operating conditions such as current density, temperature, and thermal gradients provides crucial insight into the lithium growth mechanism. Optical data is complemented with mapped synchrotron diffraction data that elucidate the vertical growth of lithium into the solid electrolyte pellet by measuring the relative intensities of lithium. These results enable comprehensive characterization of lithium growth regimes, including in-plane-growth dominant and vertical-growth dominant regimes, at successive capacities of lithium plated. Understanding these lithium growth regimes guides strategies to attain more lateral, uniform lithium deposition, with long-term implications in achieving stable, high-capacity zero-excess-lithium solid-state battery operation. References: [1] Yang-Kook Sun. Promising All-Solid-State Batteries for Future Electric Vehicles. ACS Energy Lett. 2020 , 5 , 3221-3223. [2] Christian Heubner, Sebastian Maletti, Henry Auer, Juliane Hüttl, Karsten Voigt, Oliver Lohrberg, Kristian Nikolowski, Mareike Partsch, and Alexander Michaelis. From Lithium-Metal toward Anode-Free Solid-State Batteries: Current Developments, Issues, and Challenges. Adv. Func. Mater . 2021 , 31 (51), 2106608. [3] Yuan Tian, Yongling An, Chuanliang Wei, Huiyu Jiang, Shenglin Xiong, Jinkui Feng, and Yitai Qian. Recently advances and perspectives of anode-free rechargeable batteries. Nano Energy . 2020 , 78 , 105344. [4] Eric Kazyak, Michael J. Wang, Kiwoong Lee, Srinivas Yadavalli, Adrian J. Sanchez, M.D. Thouless, Jeff Sakamoto, and Neil P. Dasgupta. Understanding the electro-chemo-mechanics of Li plating in anode-free solid-state batteries with operando 3D microscopy. Matter . 2022 , 5 (11), 3912-3934.

Solid electrolyte failure can occur through a range of different mechanisms. Electrochemical delamination at electrode and electrolyte interfaces is a prominent failure mechanism during high capacity and low N/P operating conditions, and filament formation is prevalent during high rate and long cycle-life deposition. Interface coherency and solid electrolyte microstructure both impact the ultimate degradation mode. Solid electrolyte microstructure, described in part by the density, periodicity, and interconnected arrangement of pores, plays a role in failure. Herein, we combine modeling, synchrotron imaging, and electrochemical experiments to systematically understand how densification and processing of solid electrolyte influences filament formation. The work reveals that the density of pores does not correlated with failure. Instead, the periodicity, size and arrangement of pores is a driver for failure in amorphous solid electrolytes absent of grain boundaries.

Consolidation or densification of low-dimensional MXene materials into membranes can result in the formation of asymmetric membrane structures. Nanostructural (short-range) and microstructural (long-range) heterogeneity can influence mass transport and separation mechanisms. Short-range structural dynamics include the presence of water confined between the 2D layers, while long-range structural properties include the formation of defects, micropores, and mesopores. Herein, it is demonstrated that structural heterogeneity in Ti 3 C 2 T x membranes fabricated via vacuum-assisted filtration significantly affects ion transport. Higher ion permeabilities are achieved when the dense “bottom” side of the membrane, rather than the porous “top” side, faces the feed solution. Characterization of the membrane reveals distinct differences in flake alignment, surface roughness, and porosity across the membrane. The directional dependence on permeability suggests that one region of the membrane experiences stronger internal concentration polarization, potentially suppressing permeability through the porous side of the membrane.

Abstract The interlaboratory comparability and reproducibility of all-solid-state battery cell cycling performance are poorly understood due to the lack of standardized set-ups and assembly parameters. This study quantifies the extent of this variability by providing commercially sourced battery materials—LiNi 0.6 Mn 0.2 Co 0.2 O 2 for the positive electrode, Li 6 PS 5 Cl as the solid electrolyte and indium for the negative electrode—to 21 research groups. Each group was asked to use their own cell assembly protocol but follow a specific electrochemical protocol. The results show large variability in assembly and electrochemical performance, including differences in processing pressures, pressing durations and In-to-Li ratios. Despite this, an initial open circuit voltage of 2.5 and 2.7 V vs Li + /Li is a good predictor of successful cycling for cells using these electroactive materials. We suggest a set of parameters for reporting all-solid-state battery cycling results and advocate for reporting data in triplicate.

Structural heterogeneity within solid-state electrodes can have a significant impact on material utilization and reaction rates. This reaction heterogeneity is greater in solid state systems in comparison to conventional liquid electrolytes because it requires exquisite solid-solid contact between the active energy storage materials and the solid ion conducting phase (e.g. solid electrolyte) [1]. Electrode reaction behaviors encompass electrochemical lithiation and delithiation dynamics and chemo-mechanical processes such as volume change and fracture [2]. Understanding the connection between structural heterogeneity and reaction behavior is crucial for understanding degradation mechanisms and optimizing solid state battery architectures. Herein, we examine the implications of reaction heterogeneity in an additive-free, crystallographically textured electroplated lithium cobalt oxide (LCO) cathode [3]. The electroplated dense cathode alleviates the need for any solid electrolyte material in the cathode. A diverse set of synchrotron-based operando and ex situ experiments are combined with modeling to uncover the relationship between structural heterogeneity and reaction behavior. Operando energy dispersive X-ray diffraction and ex situ 3D XANES are used to identify reaction heterogeneity and X-ray nanotomography is used to probe nano-scale structural heterogeneity. Nanoindentation is utilized to determine the mechanical properties of LCO. To validate the results, we combine these experimental results with transport and mechanics modeling. Through this comprehensive characterization approach, we confirm that the reaction behavior of cathode in our model is mainly determined by the morphological heterogeneity rather than the Li diffusion within the electrode. Structural heterogeneity causes localized high stress and leads to fracture, which in turn limit the full utilization of the cathode. Reference [1] Jung, S.H., Kim, U.H., Kim, J.H., Jun, S., Yoon, C.S., Jung, Y.S. and Sun, Y.K., 2020. Ni‐rich layered cathode materials with electrochemo‐mechanically compliant microstructures for all‐solid‐state Li batteries. Advanced Energy Materials, 10(6), p.1903360. [2] Liu, X., Zheng, B., Zhao, J., Zhao, W., Liang, Z., Su, Y., Xie, C., Zhou, K., Xiang, Y., Zhu, J. and Wang, H., 2021. Electrochemo‐mechanical effects on structural integrity of Ni‐rich cathodes with different microstructures in all solid‐state batteries. Advanced Energy Materials, 11(8), p.2003583. [3] Zahiri, B., Patra, A., Kiggins, C., Yong, A.X.B., Ertekin, E., Cook, J.B. and Braun, P.V., 2021. Revealing the role of the cathode–electrolyte interface on solid-state batteries. Nature Materials, 20(10), pp.1392-1400. Figure 1

ADVERTISEMENT RETURN TO ARTICLES ASAPPREVEnergy FocusNEXTTutorials in Electrochemistry: Storage BatteriesKelsey B. Hatzell*Kelsey B. HatzellPrinceton University, Princeton, New Jersey 08540, United States*Email: [email protected]More by Kelsey B. Hatzellhttps://orcid.org/0000-0002-5222-7288 and Prashant V. Kamat*Prashant V. KamatUniversity of Notre Dame, Notre Dame, Indiana 46556, United States*Email: [email protected]More by Prashant V. Kamathttps://orcid.org/0000-0002-2465-6819Cite this: ACS Energy Lett. 2024, 9, XXX, 3290–3291Publication Date (Web):June 14, 2024Publication History Received21 May 2024Accepted22 May 2024Published online14 June 2024https://pubs.acs.org/doi/10.1021/acsenergylett.4c01390https://doi.org/10.1021/acsenergylett.4c01390newsACS PublicationsPublished 2024 by American Chemical Society. This publication is available under these Terms of Use. Request reuse permissions This publication is free to access through this site. Learn MoreArticle Views3039Altmetric-Citations-LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail PDF (1 MB) Get e-AlertscloseSUBJECTS:Batteries,Electrical energy,Electrodes,Energy,Materials Get e-Alerts

Batteries used in space applications can be exposed to large temperature-swings. During these large temperature-swings, the battery electrolyte can undergo a phase transformation from a liquid to a solid and back to a liquid. The nature of the solvent and the type of salt influence the crystallization processes. Herein, we aim to understand how pressure build-up in confined regions of an electrode (e.g., pores) influences degradation processes in silicon-oxide graphite anodes undergoing freeze-thaw dynamics. Our results show that high porosity electrodes lead to a greater density of nucleation sites for electrolyte crystallization. Local pressure build-up at pores results in active material loss and decreased cycle lifetime in batteries exposed to extreme temperature swings.