bluuebunny/crossref_metadata_2025 huggingface dataset:
Relating Crystallographic Shear to Rate Performance in Wadsely-Roth Materials
Authors: Wyckoff Kira , Bienz Jadon , Seshadri Ram
Published: September 2023

Wadsley-Roth shear structures represent a promising and high performance class of high-voltage Nb- and W-based anode materials that intrinsically avoid SEI formation, are capable of mulitelectron redox, and suppress large lattice expansion. Currently, there is huge momentum to design faster charging batteries. Wadsley-Roth materials, typically described by their block size, have been found to display outstanding charge storage at fast rates. Within this class of materials, however, there is significant diversity in terms of block size and block arrangement. It is understood that these materials as a class are all generally high performance, but what differentiates them between each other and why? Through data aggregation and visualization, we quantitatively relate the role of shear to rate performance. We find that the structures which have block arrangements with lower amounts edge-sharing polyhedra are capable of higher capacity retention at fast rates. Our findings suggest there is an optimal amount of shear for high-rate Wadsley-Roth materials, too little and the structure will have insufficient stability, too much and the structure will have insufficient channels for Li transport. We develop more nuanced understanding on the relationship between crystallographic features and high-rate properties, informing future material design strategies for fast-charging Li-ion batteries.
LT-LiMn0.5Ni0.5O2: A Unique Co-Free Cathode for High Energy Li-Ion Cells
Authors: Shi Boyu , Gim Jihyeon , Li Linze , Wang Chongmin , Vu Anh , Croy Jason R , Thackeray Michael M , Lee Eungje
Published: September 2023

Over the past decade, designing advanced, high energy density lithium-ion batteries has become necessary because of the increasing demand for electric vehicles and energy storage devices. Research efforts have focused largely on developing layered, Ni-rich cathode materials due to their high specific capacity. However, their structural and thermal instability and the relatively high cost of nickel raises a concern about their long-term viability.1 Developing next generation cathode materials, based on earth abundant elements such as manganese and iron, has therefore attracted much research interest.2

In the late 1990s, the Mn-based spinel cathode, LiMn2O4 (LMO), dominated the early development of Li-ion batteries for the electric vehicle market. The 3-D network of channels provided by the Mn2O4 spinel framework for Li+-ion diffusion channels enables a good rate performance. However, the operational capacity of Li1-xMn2O4 spinel cathodes in a lithium cell at ~4 V over the range 0<x£1 is limited by its low electrochemical capacity relative to layered cathodes. Although deep-discharging the cell at ~3 V allows the insertion of extra Li ions into the spinel framework (i.e., Li1+xMn2O4, 0£x£1), a rapid fade of capacity occurs as a result of a severe crystallographic (Jahn Teller) distortion, which prevents the use of the lower voltage reaction in commercial cells.

In this presentation, a novel LT-LiMn0.5Ni0.5O2 (LT-LMNO) cathode material with unique electrochemical properties will be reported, where LT refers to its low synthesis temperature (400 °C). In striking contrast to a layered electrode with the same composition, HT-LiMn0.5Ni0.5O2 (where HT = high temperature synthesis, ~850 °C), LT-LMNO has a composite configuration with structurally-integrated lithiated spinel- and layered-like components.3,
4 It provides an electrochemical capacity almost twice that of LMO. This discovery provides a new strategy for developing next-generation. Mn-rich spinel-based cathodes.

References

Bianchini, M.; Roca-Ayats, M.; Hartmann, P.; Brezesinski, T.; Janek, J., There and Back Again - The Journey of LiNiO2 as a Cathode Active Material. Chem. Int. Ed. Engl.
2019,
58 (31), 10434-10458.

Croy, J. R.; Gutierrez, A.; He, M.; Yonemoto, B. T.; Lee, E.; Thackeray, M. M., Development of Manganese-rich Cathodes as Alternatives to Nickel-rich Chemistries. Power Sources
2019,
434, 226706.

Thackeray, M. M.; Lee, E.; Shi, B.; Croy, J. R., Review: From LiMn2O4 to Partially-Disordered Li2MnNiO4: The Evolution of Lithiated-Spinel Cathodes for Li-Ion Batteries. Electrochem. Soc.
2022,
169 (2), 020535.

Shi, B.; Gim, J.; Li, L.; Wang, C.; Vu, A.; Croy, J. R.; Thackeray, M. M.; Lee, E., LT-LiMn5Ni0.5O2: A Unique Co-free Cathode for High Energy Li-ion Cells. Chem. Comm.
2021,
57 (84), 11009-11012.
(Invited) Solvation and Double Layer Structures in Nonaqueous Electrolytes for Facile Electrochemical Kinetics
Authors: Bai Peng
Published: September 2023

Nonaqueous electrolytes are indispensable for high-voltage/high-energy electrochemical systems. They are particularly important for batteries that can work normally at very low temperatures and can be recharged at high C-rates. Under these extreme conditions, solvation and double layer structures at the electrolyte-electrode interfaces, which were considered less critical than other processes like solid-phase diffusion, appear to play an important role in enabling fast reaction kinetics. Due to the use of multiple co-solvents, salt mixtures, and various additives in novel nonaqueous electrolytes, the interfacial solvation and double layer structures are no longer as simple as the classical understanding based on aqueous electrolytes. In this presentation, we will introduce our recent efforts in realizing fast ion intercalation (both anions and cations) in graphite electrodes and ideally stable alkali metal plating in nonaqueous electrolytes in wide ranges of current densities and temperatures. By combining classical molecular dynamic (MD) simulations of the interfacial electrolyte structure near a charged electrode, density functional theory (DFT) calculations of the distorted solvation structures, operando microscopy of the electrode reactions, and postmortem chemical analysis of the solid-electrolyte interphase (SEI) layers, we confirmed the importance, necessity, and principle of formulating high-performance electrolytes based on molecular scale understandings of the complex interfacial structures.
(Invited) Challenges in Multiscale Modeling of Electrochemical Energy Storage Systems
Authors: Liaw Boryann (Bor Yann) , Li Meng , Pawar Gorakh Machindranath
Published: September 2023

Multiscale modeling for energy storage systems is a favorite subject for many applications from basic understanding of the properties of energy storage materials in the molecular level to system operation and performance at scales. Frequently, the challenges faced by the modelers are often focused on the technical barriers and issues such as parameterization and modeling framework. The challenges in the fundamental science are much less discussed. Here we will provide some perspectives on basic science aspects and explain how they impact the theoretical framework in multiscale model and approaches. We will use the Li metal as an example to explain how the properties of Li reflect its chemical stability, how the environment impacts its chemical stability, and how electrochemical stripping and deposition affect its stability. As this basic understanding developed from the molecular level extends to different spatial and temporal scales, what challenges we are facing in the modeling framework that impede our realization of the predictions accurately for various applications.
(Keynote) Heterogeneities in Solid-State Battery Interfaces and Architectures
Authors: Mukherjee Partha P. , Vishnugopi Bairav Sabarish , Naik Kaustubh Girish
Published: September 2023

While lithium-ion batteries have garnered significant success over the past decades, the development of next-generation batteries with higher energy densities is crucial for future electromobility demands such as long-range electric vehicles and electric aviation. In this context, solid-state batteries (SSBs), consisting of an inorganic solid electrolyte and lithium metal, are promising in simultaneously improving the energy density and safety. Despite their irrefutable promise, the realization of practical SSBs is predicated on overcoming important challenges pertaining to electro-chemo-mechanics, transport, and interface evolution. Myriad heterogeneities ranging from defects/voids at the lithium/solid electrolyte interface, grain boundaries in the solid electrolyte and singularities in the solid-state cathode have a pivotal influence on the onset of failure and electrochemical performance. In this presentation, the critical role of heterogeneities on the mechanistic interplay at solid-solid interfaces and the underlying failure mechanisms will be delineated. Governed by the manifestation of spatio-temporal heterogeneity at scales, the origin of solid/solid interface instability, resultant asymmetry in the plating/stripping response and electrode crosstalk implications will be discussed.
(Invited) Open-Source Software and Open Data to Accelerate the Development of Energy Storage Systems
Authors: Preger Yuliya , De Angelis Valerio
Published: September 2023

Many of the products we use in our daily lives, ranging from smartphones to web servers to cars, are based on a significant amount of open-source software. This approach has enabled standardization and rapid innovation in the tech industry. However, energy storage systems are typically not standardized in terms of components or software, leading to replicated development efforts across companies and significant balance of system costs. This talk will explore various efforts to publicly release data, software, and hardware to accelerate the development of energy storage systems. Examples include Battery Archive, the first public site for sharing battery data across institutions; control software for hybrid-batteries, available on GitHub; and a standard rack design for operating new batteries. These efforts will be described in the context of the need for physics-model driven battery operation and control of different types of batteries.

Sandia National Laboratories is a multimission laboratory managed and operated by National Technology & Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525.
Modeling and Analysis of Temperature-Dependent Capacity Degradation in Large Format Lithium-Ion Batteries
Authors: Mishra Lubhani , Subramaniam Akshay , Garrick Taylor R. , Subramanian Venkat R.
Published: September 2023

The large-format lithium-ion batteries, widely used for electric vehicle applications, are generally characterized by spatial non-uniformities in temperature. The presence of thermal gradients and temperature-dependence of cell parameters are responsible for non-uniform degradation within the battery that leads to poor performance of the battery packs and also poses safety risks. In this work, we aim to develop a detailed physics-based simulation framework to model non-uniform, temperature-dependent capacity degradation within these large format batteries based on the classical pseudo two-dimensional (p2D) battery model. The electrochemical model will be coupled with degradation mechanisms to capture solid-electrolyte interface layer growth, reversible lithium plating, structural disintegration, and volume change within the electrodes on the cell level signatures and usable capacity over charge/discharge cycles. The effects of temperature inhomogeneities will be accounted in the multi-cell simulations at different operating temperatures for individual cells with dynamic currents and temperature and concentration dependent battery parameters as the model inputs.

Overall, the primary focus of this study is to capture the effect of spatial temperature variation on battery capacity over cycles and help identify an improved design for the battery module. The model is implemented in an efficient equation-based form for the p2D model and degradation mechanisms with dynamic cell inputs using the mathematical modules in the finite element based solver, COMSOL Multiphysics. This approach enables an easier model development and analysis of the detailed physics and allows an easier implementation of any additional side reaction. The relative contributions of various fade modes have also been compared to understand their competitive interplay over cell cycles. The model predictions are validated with the available experimental data and in-house codes for each case. We believe that this simple yet detailed model can be further developed to be computationally feasible for adoption and implementation in a battery thermal management system.
Understanding Characteristic Electrochemical Impedance Spectra of Redox Flow Batteries with Multiphysics Modelling
Authors: Alhammadi Ayoob , Fetyan Abdulmonem , Susantyoko Rahmat Agung , Bamgbopa Musbaudeen O.
Published: September 2023

Abstract

Electrochemical impedance spectroscopy (EIS) is a non-destructive technique for analyzing electrochemical systems (such as redox flow batteries – RFBs). Battery researchers widely adopt equivalent circuit models (ECMs) to analyze EIS spectra of RFBs and attempt to use the circuit to deduce prevalent transport and kinetic properties [1]. Straightforward adoption of these ECMs suffers from some setbacks which need rectifying. There is a major issue of poor or inconsistent physical interpretation of the different circuit elements. ECMs of batteries are commonly used in real-time applications due to their simplicity and importance for determining properties like state-of-charge. However, prediction performance in low state-of-charge areas has to be improved [2], which reinforces the need to relate recorded spectra to the physical properties of cell components.

Using an experimentally validated full Multiphysics model of single-cell vanadium RFB analyzed in the frequency domain, we approach understanding the EIS spectra characteristics based on the influence of cell features and operating parameters. To achieve our analyses, we investigate the effects of different cell properties and operating parameters on the Multiphysics model produced EIS spectra and the resulting ECM circuit element parameters that fit the spectra. Five different values for each cell property or operating parameter are considered for the following components:

Electrode: Electrical conductivity, porosity vis a vie specific surface area and hydraulic permeability, reaction rate constants for the positive and negative sides.

Membrane: Ionic conductivity, fixed charge concentration, porosity, and hydraulic permeability.

Electrolyte: State-of-charge, Composition vis a vie bulk diffusion coefficients of species, density, and viscosity.

References

[1] A.K. Tripathi, D. Choudhury, M.E. Joy, M.J.J.o.T.E.S. Neergat, Electrochemical Impedance Spectroscopic Investigation of Vanadium Redox Flow Battery, 169 (2022) 050513.

[2] Y.A. Gandomi, D. Aaron, T. Zawodzinski, M.J.J.o.T.E.S. Mench, In situ potential distribution measurement and validated model for all-vanadium redox flow battery, 163 (2015) A5188.
Stress-Strain and Resistance-Strain Hysteresis in Single-Wall Carbon Nanotube Films for Stretchable Battery Electrodes
Authors: Mohanty Shaswat , Kuznetsov Oleg A , Harutyunyan Avetik R. , Cai Wei
Published: September 2023

The need to protect the vulnerable and limited resources that are naturally available while meeting the growing energy demand of the world makes the sustainable development of renewable energy of paramount importance. To address these needs, a new type of battery electrode has been developed at Honda Research Institute (HRI), based on free-standing single-wall carbon nanotube (SWNT) films containing active battery materials as dispersed nanoparticles. The SWNT films provide both mechanical support and electrical conductivity, removing the need for metal electrodes (increasing the energy density of the battery) and binder materials (making the process environmentally friendly).

Under cyclic strain, the SWNT-based electrodes show hysteretic behaviors in both stress-strain and electrical resistance-strain relations. The electrical resistance-strain behavior shows a different trend from the previously observed behavior on 2D SWNT films (on elastic substrate). We hypothesize that this change can be attributed to the differences in the SWNT network structures in the 2D and 3D films. To understand the microscopic origin of the hysteresis, we performed coarse-grained molecular statics (CGMS) simulations of the SWNT film. The simulations show that the intrinsic Van der Waals interaction between SWNTs is responsible for the observed robust mechanical properties of the electrodes. In addition, our study also reveals that the sparsity of the 3D morphology results in the current being carried across the simulation box only by a few paths. As a consequence, the resistance hysteresis is governed entirely by the change in the power-carrying capacity of the network due to the breaking and formation of contacts between the SWNTs during loading-unloading. The qualitative nature of the resistance-strain hysteresis can thus be attributed to the rapid formation of inter-nanotube contacts, as the nanotube bundles (elongated by initial loading) buckle during unloading.
(Invited) Model-Predictive Design of Low Pt Loaded PEMFC Catalyst Layers
Authors: DeCaluwe Steven C. , Randall Corey R
Published: September 2023

Proton exchange membrane fuel cells (PEMFCs) are a promising means to decarbonize the global vehicle fleet, but commercialization is limited by costly Pt catalysts, among other challenges. PEMFC designs with low Pt loading typically suffer anomalous performance losses. Previous studies have agreed that poor device performance is linked to complex physiochemical processes in the cathode catalyst layer (CL) [1]. More specifically, poor performance with low Pt-loading is attributed to sluggish proton and/or oxygen transport through the nano-thin Nafion ionomer in the CL. Previous studies have also identified that the properties of the Nafion thin films in the CL vary from those previously measured for thicker membranes. However, research has not yet definitively connected CL polymer properties with PEMFC limitations in low Pt-loaded cells, nor found a means to address the limitations for low cost, higher-performance PEMFCs.

In this presentation, we will describe efforts to quantify structure-property relationships for thin-film Nafion and incorporate these relationships into PEMFC numerical simulations to identify advantageous PEMFC catalyst layer designs. We model nm-scale transport in thin-film Nafion to develop structure-property relationships for thin-film Nafion, based on in situ neutron reflectometry [2], and conductivity measurements [3] on thin film Nafion. These result in a model that calculates the conductivity as a function of temperature, local water uptake, film thickness, and underlying substrate (Pt or carbon). Incorporating these structure-property models into a continuum-scale PEMFC cathode half-cell model to locally resolve proton conductivity and O2 diffusion improves model fits to PEMFC data with varying Pt loading [4]. The fits provide new insights into the coupling between kinetic, mass transport, and Ohmic losses in low-Pt-loaded PEMFC cathodes and show that Ohmic losses in thin film Nafion play a key limiting role in low-Pt loaded cells. We conclude with a parametric study of PEMFC CL design parameters with low Pt loading. Incorporating multi-scale modelling of Nafion transport processes enhances the predictive model capabilities and unlocks new insights into CL design. We will present a detailed analysis of how best to manage coupled limiting phenomena in PEM fuel cells, and identify functionally graded catalyst layer designs that could significantly improve PEMFC power density with low Pt loading [4].

Weber, A. and Kusoglu, A. Mater. Chem. A.
2014. DOI: 10.1039/c4ta02952f

DeCaluwe, S.C. et al. Nano Energy
2018. DOI: 10.1016/j.nanoen.2018.01.008

Paul, D.K. et al. Electrochem. Soc.
2014. DOI: 10.1149/2.0571414jes

Randall, C.R. and DeCaluwe, S.C., Electrochem. Soc.
2022. DOI: 10.1149/1945-7111/ac8cb4
Control of Nanoparticle Dispersion, SEI Composition, and Electrode Morphology Enable Long Cycle Life in High Silicon Content, Nanoparticle-Based Composite Anodes for Lithium-Ion Batteries
Authors: Carroll Gerard (MIke) Michael , Schulze Maxwell , Urias Fernando , Dutta Nikita , Huey Zoey , Coyle Jaclyn , Teeter Glenn , Doeren Ryan , Tremolet de Villers Bertrand J. , Han Sang-Don , Neale Nathan R.
Published: September 2023

Striking a balance between high theoretical capacity, Earth abundance, and compatibility with existing manufacturing infrastructure, silicon is one of the few materials that meets the requirements for a next-generation anode for rechargeable lithium-ion batteries. Due to complications with extreme volume changes during charging/discharging and reactive interfacial chemistries, however, the cycle-life of silicon-based composite anodes is unacceptable for broad use. Developing a majority silicon composite anode formulation that overcomes these challenges and is compatible with current industry manufacturing practices requires materials and chemical engineering solutions that account for both electrode morphology and interfacial chemistry. Here, we synthesize surface-functionalized silicon nanocrystals that enable a highly dispersed and homogeneous slurry that can easily be integrated into standard electrode fabrication process. We use this formulation to print a 76 wt. % silicon composite electrode. We show that the contents and the morphology of the silicon electrolyte interphase – a determining factor in the cycle life of silicon-based anodes – can be controlled with a post-synthetic thermal curing procedure. When paired against a capacity-matched lithium nickel manganese cobalt oxide LiNi0.8Mn0.1Co0.1O2 cathode, the cell retains 72% of its capacity through 1000 charge/discharge cycles while delivering an initial anode specific capacity of nearly 1000 mAh/g and an areal capacity of 2.55 mAh/cm2.

Figure 1
Investigating the Structure and Performance Differences between the Electrodes Made by a Dry and a Wet Slurry Processes
Authors: Uzun Kubra , Sharma Bhamiti , Huang Xiaosong , Frieberg Bradley , Hu Jiazhi , Wang Ming , Cheng Yang-Tse
Published: September 2023

In the conventional wet slurry method for making lithium-ion battery (LIB) electrodes, unwanted N-Methyl-2-Pyrrolidone (NMP) solvent is used. The use of NMP increases the overall energy demand during electrode coating since NMP needs to be dried from the coated slurry and recovered. The improper use of NMP can also impose detrimental effects on health and the environment. Thus, solvent-free dry processes are gaining increased interest worldwide for electrode fabrication. Amongst different dry electrode manufacturing techniques, electrostatic spray deposition (ESD) is one of the most promising techniques. In this study, positive LiNi0.8Co0.1Mn0.1O2 (NMC811) electrodes were manufactured by the ESD process and wet slurry process. The differences between the electrodes made by these two processes were investigated by the peel strength test, electrochemical techniques (e.g., rate tests, electrochemical impedance spectroscopy, and constant voltage/constant current cycling), scanning electron microscopy with energy dispersive x-ray spectroscopy, and X-ray photoelectron spectroscopy. In the dry electrodes, most active material particles were densely covered by the binder and conductive agents. Whereas in wet slurry electrodes, binder and conductive agents were distributed more homogenously both on the active material surfaces and between the active material particles. The uniform distribution of the binder and conductive agents in the slurry electrodes results in a robust conductive network, leading to better performance at high C- rates (e.g., 2-5C). Interestingly, the dry electrodes had comparable performance to slurry electrodes at the initial stages of electrochemical testing with low current rates. Hence, it can be concluded that the distribution of the electrode materials affects active material usage and the conductive paths, and a homogenous distribution is needed to achieve faster discharge capacity at higher C rates. Future work will focus on the long-term cycling performance of the electrodes to further understand the degradation mechanisms and differences between the two types of electrodes.
Insights into the Correlation Among Porosity, Mechanical Properties, Morphology, Electrical Conductivity and Electrochemical Performance of Dry-Processed Cathodes
Authors: Tao Runming , Steinhoff Bryan , Sardo Kahla , Skelly Brendan , Hill Ryan Christopher , Uzun Kubra , Cheng Yang-Tse , Hong Kunlun , Li Jianlin
Published: September 2023

The conventional lithium-ion battery (LIB) electrode preparation heavily relies on the n-methylpyrrolidone-based wet processing, which is time- and energy-consuming due to the involved recycle and recovery of n-methylpyrrolidone. In recent years, researchers have proposed dry processing (DP) as a promising alternative strategy, which is mainly based on dry mixing of electrode component powder followed by calendar into electrode films and laminating onto current collectors, realizing the facile preparation of LIB electrodes for industrial manufacturing in powder-to-film manner. However, as a state-of-the-art route, many fundamental sciences of the DP-based electrodes are unclear, especially the compression effect. It exhibits pronounced impacts on the porosity, mechanical properties, morphology, electrical conductivity and electrochemical performance of electrodes. Herein, taking NMC811 electrode as a proof of concept, the correlation among the aforementioned aspects will be discussed in this presentation.
Lithium Ion Battery Electrolytes Based on Deep Eutectic Solvents
Authors: Elgammal Ramez Ahmed , Fraenza Carla Cecilia , Zawodzinski Thomas A. , Greenbaum Steven
Published: September 2023

Deep eutectic solvents (DESs) have emerged as an alternative to both common organic solvents and ionic liquids (ILs). DESs share physicochemical properties with ILs such as low vapor pressure, high thermal stability, while offering advantages such as low toxicity, lower cost, and ease of preparation. Moreover, DESs are attractive candidates for electrochemical applications due to their large voltage windows and solubility properties. DESs as a solvent class share a general composition of a hydrogen bond donor (HBD), typically a polyol, amide, or acid, and a hydrogen bond acceptor (HBA), usually a quaternary ammonium or phosphonium salt. At a specific molar composition of a HBD and HBA, the DES forms a eutectic mixture resulting in a large melting point depression.

Despite being widely studied, the microscopic structures of DESs have remained largely uncharacterized. Herein, we present a multitechnique NMR study of ethaline (ethylene glycol + choline chloride). Pulsed field gradient diffusion, nuclear Overhauser effect spectroscopy (NOESY), 13C NMR relaxation experiments are deployed to sample a range of frequencies and modes of motion of the polyol and choline components of the DES. Generally, translational and rotational diffusion of polyols are more rapid than those of choline while short-range rotational motions observed from 13C relaxation indicate slow local motion of ethylene glycol at low choline chloride (ChCl) content.

Additionally, we have investigated the solubility properties of several lithium salts (LiTFSI, LiFSI, LiBF4, and LiOAc) in these DESs and utilized the same suite of NMR techniques to understand how they act as solvents. One interesting observation is that the Li+ diffusivity exceeds that of the counterion for TFSI-, but not for FSI-. Finally, large changes in the structural organization of DESs that result from the presence of lithium salts may serve as a guide to the design of a new class of electrolytes for lithium-ion batteries.
Fluorinated Battery Electrolytes for Low Temperature Cycling
Authors: Guillot Sarah Lucienne , Usrey Monica Lee , Du Peng , Kerber Brian M , Zhou Liu (Amy) , Garg Shipra , Sriramulu Suresh
Published: September 2023

Lithium-ion batteries often see dramatic capacity losses when cycling at low temperatures, due to sluggish lithium transport within the bulk electrolyte and at the electrode-electrolyte interfaces. The development of new battery electrolytes with enhanced lithium-ion conductivity and improved interfacial transfer at low temperatures is needed to improve the overall stability and wide operating range performance of batteries. Koura has developed fluorinated materials for lithium-ion electrolytes with improved stability and safety properties, and in this study their efficacy in batteries under low temperature conditions is investigated and compared to conventional electrolytes. Fundamental transport properties such as lithium transference number, conductivity, and viscosity are reviewed. Cycling and rate performance across a range of temperatures from -20°C to 45°C are also investigated, and interfacial properties are assessed. By combining analyses of the bulk electrolyte properties, interfacial electrochemistry, and performance data at several temperatures, a comprehensive picture of the effect of electrolyte on low and wide temperature performance is developed. Experimental results show that several of Koura’s fluorinated materials can improve low temperature cycling performance, and key considerations in optimizing electrolyte properties and composition for low temperature performance are discussed.
(Invited) High-Throughput Development of LiCoPO4
Authors: Zeinali Galabi Nooshin , Jia Shipeng , Jonderian Antranik , Yoon Gabin , MA Sang Bok , McCalla Eric
Published: September 2023

High voltage cathodes are attractive for high energy density Li-ion batteries, particularly with the innovation of solid electrolytes with large stability windows. However, candidates such as LiCoPO4 have presented numerous problems due to poor electronic/ionic conductivities. Typical solutions involving nanosizing result in extremely poor cycling performance. Herein, we first apply high-throughput methods to develop near-micron sized carbon-coated LiCoPO4 with improved energy density and capacity retention.1 In total, 1300 materials with 46 different substituents were synthesized and characterized. A number of substituents showed greatly improved capacity (e.g. 160 mAh/g for 1% In substitution vs. 95 mAh/g for the pristine). However, co-doping was required to improve extended cycling. Li1-3xCo1-2xInxMoxPO4 was found to be particularly effective with dramatically improved cycling (as high as 100 % after 10 cycles, vs. ~50 % in unsubstituted). While In improved the electronic conductivity of the carbon-coated materials, Mo co-doping gave larger particles and DFT calculations showed that Mo impedes the formation of Li/Co antisite defects.

While the above described experiments were solely guided by the researchers intuition, we also explore potential benefits of using machine-learning (ML) algorithms to guide the composition exploration. Random compositions were first prepared to supplement our existing data as part of the training set, then further synthesis was performed based on the ML outputs. The results will be presented in detail to help establish to what extent ML can be used to further leverage our group's high-throughput data.

References

1. A. Jonderian, S. Jia, G. Yoon, V.T. Cozea, N. Zeinali Galabi, S.B. Ma, and E. McCalla. Accelerated Development of High Voltage Li-Ion Cathodes. Adv. Energy Mater. 2022, 12, 2201704.
Studying the Mechanics of NMC Cathode Particles for Direct Battery Recycling
Authors: Preimesberger Juliane Irine , Coyle Jaclyn
Published: September 2023

As the global usage of lithium-ion batteries skyrockets, there is increasing interest in recycling spent batteries. While the economic and environmental impacts of reclaiming high-value elements such as cobalt, nickel, and lithium are obvious, directly-recycling cathode materials takes this one step further by both recovering these elements as well as preserving particle structure, which takes significant processing cost and materials to manufacture. Previous literature has found a correlation between mechanical strength and cyclability of cathode materials, indicating that restoring the structural integrity of active particles is crucial to direct recycling efforts [1, 2]. Cathode materials experience significant fracture and cracking during the lifetime of a battery, caused by both the calendering process during formation and the volume expansion of the particles upon lithium insertion during cycling [1]. Many recycling processes rely on high-temperature annealing to repair cracks in end-of-life cathode particles. As fracture due to calendering exists in pristine electrodes, it is possible that the annealing step does not need to heal all cracks in end-of-life material to match pristine electrode performance. To lower recycling costs, it is vital that the requirements for the annealing step are well understood.

To address this, we characterize the mechanical strength of nickel manganese cobalt (NMC) cathode particles at pristine, end-of-life, and recycled-annealed states. We leverage multiple experimental techniques, including bulk compressive testing, nanoindentation, and nano-CT measurements, to characterize the particles’ bulk modulus, Weibull distribution, and fracture toughness, among others, and correlate these mechanical properties to cycling performance. From this, we provide insight into an optimal annealing step that minimizes cost without sacrificing recycled material mechanical and electrochemical quality.

References:

[1] I. Hamam, R. Omessi, D. Rathore, C. Geng, R. Cooke, K. Plucknett, D. P. Bishop, N. Zaker, G. A. Botton, C. Yang and J. R. Dahn, "Correlating the mechanical strength of positive electrode particles to their capacity retention," Cell Reports Physical Science, vol. 3, no. 100714, 2022.

[2] R. Xu, H. Sun, L. S. de Vasconcelos and K. Zhao, "Mechanical and Structural Degradation of LiNixMnyCozO2 Cathode in Li-Ion Batteries: An Experimental Study," Journal of The Electrochemical Society, vol. 164, no. 13, pp. A3333-A3341, 2017.
The Effect of Carbon Type and Solvent/Binder Ratio on the Structure and Performance of Sulfur Cathodes in Lithium-Sulfur Batteries
Authors: Lateef Saheed Adewale , Manjum Marjanul , Chmiola John , Albano Fabio , Mustain William Earl , Jalilvand Golareh
Published: September 2023

Lithium-Sulfur (Li-S) batteries are among the popular candidates for next-generation rechargeable energy storage devices due to their high specific capacity and superior energy storage capabilities. However, commercialization of Li-S batteries has been hindered by several challenges such as the insulating nature of sulfur, and the shuttling of soluble lithium polysulfides and accumulation of insulating deposits on the electrodes – leading to capacity degradation over extended cycling1.

Several research efforts have been devoted to mitigating these challenges. Among the different approaches, many studies focus on addressing the poor conductivity of sulfur and lithium polysulfide shuttling simultaneously by developing conductive carbon hosts2,3. While improvements have been achieved in the development of host structures with better electronic conductivity and improved polysulfide trapping capability, many of those structures have advanced architectures that demand complex processing, expensive precursors, and often lower gravimetric sulfur loading (<70 wt%).This leads to expensive-to-produce electrodes that have lower true energy density than desired. What is needed are simple preparation methods that address the issues discussed above without overly complicated processing, and preferably already commercialized materials.

In this work, we systematically investigate the effect of different electrode components, including various common carbons and polymeric binders. The effect of carbon type and loading is discussed. The effect of solvent to binder ratio in the electrode slurry preparation is also studied. By tuning the binder composition, types of conductive carbon black, and the amount of solvent, we observed a difference in the structure of the host medium and consequently the sulfur electrode. Specifically, a shell covering surrounding the sulfur particles was observed at low solvent/binder ratio. Increasing the solvent/binder ratio led to the disappearance of the shell coverings and particle agglomeration, which resulted in lower achieved capacity and reduced cycle life. Ketjen black offered the highest specific capacity, while the presence of shell covering achieved at a low solvent/binder ratio was found necessary for cycling stability.

This work demonstrates the importance of electrode processing parameters on the structure and electrochemical performance of sulfur cathode in Li-S batteries. The new understandings from this work can provide guidance on electrode designs to achieve Li-S batteries with enhanced capacity and longevity.

References

G. Li et al., Adv. Mater., 30, 1705590 (2018).

D.-W. Wang et al., J. Mater. Chem. A, 1, 9382 (2013).

Y. Li and S. Guo, Matter, 4, 1142–1188 (2021).
Understanding Carbon Dioxide Electrochemical Reduction in Aprotic Solvents
Authors: Amanchukwu Chibueze
Published: September 2023

Carbon dioxide (CO2) conversion is vital because it provides a pathway to efficiently valorize CO2 and incentivize CO2 capture. Electrocatalytic CO2 conversion is of great interest because it is scalable and can be done at ambient temperature and pressure. However, these reactions are typically performed in water which suffers from undesired hydrogen evolution reaction (HER) from water breakdown. Furthermore, catalyst selection is often determined by the ability of the catalyst to favor CO2RR over HER. Aprotic nonaqueous electrolytes can suppress HER and enable a wider range of catalysts for CO2RR. Here, we study the influence of aprotic electrolyte solvent on CO2RR. Firstly, we probe the ability of aprotic electrolytes to enable earth-abundant catalysts for CO2RR to CO. Secondly, we understand the influence of dissolved water and water solvation in aprotic electrolytes and the ability of aprotic electrolytes to enhance or suppress HER. Our work pushes the field in the understanding of electrolyte solvent and water effects for electrochemical transformations such as CO2RR and HER
Tuning Exsolution of Nanoparticles in Defect Engineered Ruddlesden–Popper oxides for efficient CO2 electrolysis
Authors: Liu Zhengrong , Sun Yueyue , Yang Jiaming , Fu Lei , Zhou Jun , Wu Kai
Published: September 2023

Solid oxide cell (SOC) is the energy conversion device with a series of advantages such as high efficiency, environmental friendliness and durability, making it a promising way to deal with environmental pollution and energy crisis appearing with the development of human society. Perovskite oxides with hetero-phases which were prepared by in-situ exsolution are widely used as fuel electrode in SOC. In this work, Ni-doped perovskites Ruddlesden–Popper oxides, (La, Sr)nTinO3n-2 with n = 5, 8, and 12 (LSTNn), were synthesized to design novel exsolution materials as solid oxide fuel cell anodes and for electrochemical catalysis applications.

Compared with pure LSTNn without Ni, a small A-site deficiency (10%) promoted the exsolution of Ni from the perovskite oxides of Ni-doped LSTNn. It is found that the morphology as well as electrochemical activity of LSTNn anodes can be successfully manipulated by the exsolution of Ni. Since more Ni nanoparticles are exsolved from the parent oxides, LSTN8 displays better electrochemical performance by providing more active sides during the hydrogen oxidation reaction and significantly lowering electrode polarization resistance. DRT analysis is conducted to study substeps of the whole electrode reaction, finding that in-situ precipitation improves rate-limiting steps much. The CO2 reduction reaction performance of LSTN materials is also studied, finding that in-situ grown nanoparticles on surface of LSTN significantly increases the density of surface active sites and three phase boundaries (TPBs), which are beneficial for CO2 adsorption and subsequent conversion.

It is clear from these results that varying Ni-doping in Ruddlesden–Popper oxides is a key factor in controlling the electrochemical performance and catalytic activity for hydrogen oxidation reaction in solid oxide fuel cells.
(Invited) Successes and Bottlenecks in Scaling CO2 and CO Electrolysis for Commercial Demonstration
Authors: Romiluyi Oyinkansola
Published: September 2023

The electrochemical conversion of carbon dioxide or carbon monoxide allows for the simultaneous production of value-added chemical feedstocks with greenhouse gas emission mitigation. Scalable CO2/CO reduction requires electrolyzers that operate with high current densities, efficiencies, durabilities, and product selectivities for carbon-containing products of high market value or size (e.g. carbon monoxide (syngas), formic acid, methane, ethylene, ethanol, and 1-propanol), with the potential for some of the resulting products to be industrially upcycled to higher-order hydrocarbons. In this talk, an overview of Shell's recent efforts in derisking these electrochemical processes are presented, as well as a discussion of persistent bottlenecks that must be overcome for commercially viable demonstrations to be implemented in the near future.
(Invited) Investigations of Electrochemical CO2 Reduction with Differential Electrochemical Mass Spectrometry
Authors: Clark Ezra L
Published: September 2023

Differential electrochemical mass spectrometry (DEMS) is an analytical technique wherein an electrochemical reactor is interfaced with a mass spectrometer using a pervaporation membrane. This configuration enables volatile electrochemical reaction products to be continuously collected, identified, and quantified during steady state and dynamic polarization. The capabilities of this analytical technique are highly dependent on the design of the electrochemical reactor and how it is interfaced to the mass spectrometer. This presentation will introduce a variety of different DEMS cell designs and will compare their capabilities and limitations in terms of product sensitivity, product quantifiability, and time response. These comparisons will be illustrated through a series of vignettes investigating the electrocatalysis of CO2 reduction over Cu, Ag, and Au. This reaction is particularly difficult to investigate with DEMS since many of the reaction products yield identical mass fragments upon electron impact ionization. A general strategy for deconvoluting the extent to which a given product contributes to the observed mass ion currents will be presented. The utilization of DEMS for the direct observation of both the composition of the local reaction environment and the transient formation of intermediate reaction products will be discussed, as well as how these insights can be leveraged to guide rational electrocatalyst design. Finally, a new type of DEMS setup capable of quantifying the steady state surface coverage and surface lifetimes of electrochemical reaction intermediates will be presented.

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Efficient Ni-N-C Gas Diffusion Electrodes for Near Neutral and Acidic CO2 Reduction in a Zero-Gap Configuration
Authors: Brückner Sven , Ju Wen , Strasser Peter
Published: September 2023

The electrochemical CO2 reduction can be a key technology for a fossil free future but for industrial applications it is necessary to analyse and understand the cathode. As one of the main problems is the low utilization efficiency of CO2 in AEM approaches due to the carbonate formation we have to find solutions to solve carbonate formation by maintain high selectivity.

In this work we investigated NiNC cathode GDEs for CO2 reduction to CO in a zero-gap MEA cell regarding their activity in a classic AEM, BPM and CEM approach. We show that the CO2 access of the catalyst is important to achieve a high performance. In an AEM approach with near neutral conditions on the anode we can reach 85% FE towards CO at 300 mA cm-2 at 3.6 V with single pass conversion of 40% which is close to the theoretical maximum. In addition, we can report high energy efficiency but only a utilization efficiency of around 50%.

Our newly introduced CCC value give information about the consumption of CO2 by the produced OH- during the CO2RR. The CCC value in combination with the selectivity enable insights in the mass transfer during the CO2 reduction in an AEM setup and give information about the accessibility of the catalyst and in addition we can monitor the flooding.

On the other Hand, we show that our NiNC GDE is stable under acidic conditions in a PEM and BPM zero-gap cell. The protons help to increase the utilization efficiency as the carbonate will react back to CO2 and water. Therefore, we investigated the activity with DI water and diluted H2SO4 at the anode and the protons in the BPM approach will be generated in situ due to water dissociation. In pure water, 0.01 and 0.1M H2SO4 we can achieve a selectivity above 80% towards CO at 100 mA cm-2 with cell potentials around 3 V which are comparable to the AEM configuration with 0.1M KHCO3. If we use a BPM approach, we can even push the single pass conversion towards CO to 70% at 500 mA cm-2.

The CCC value is in the perfect case 0 as we do not consume any additional CO2 but can indicating flooding as the CCC is rising. This indicates water accumulation which can hinder the neutralization of the carbonate/OH- and CO2 will be consumed and can precipitate in the flow channel.

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Modeling the Local Environment inside a GDE Pore for CO2 Electrochemical Reduction
Authors: Butt Esaar Naeem , Padding Johan Tiemen , Hartkamp Remco
Published: September 2023

Porous Gas Diffusion Electrodes (GDE) have gained a lot of attention in recent years for their ability to overcome the solubility and mass transfer limitations of a planar electrode assembly in CO2 electrochemical reduction (CO2ER) systems. In this work, we present a continuum scale modeling technique based on a set of size-modified Poisson-Nernst-Planck (SMPNP) equations to accurately account for the local environment including the Electric Double Layer (EDL) inside a catalytic nanopore. Most GDE models for CO2ER ignore the EDL or are limited in their applicability at relevant applied potentials due to numerical instability. The local conditions found inside an EDL heavily influence the charge transfer reactions and thus the productivity of desired CO2ER products. Our SMPNP model is able to solve for the concentration and electric field profiles at practical cathodic potentials. We highlight the variation of the predicted CO2 concentration which is often assumed to remain uniform along the radii of the catalytic pores even at high applied potentials. The predicted pH profile also varies significantly along the pore radius, influencing both the CO3
2- balance and the charge transfer reactions. Geometrical parameters such as the diameter and length of the pore, influence the electric field and can potentially be used as control parameters for increasing the selectivity of desired products. We also discuss the implications of double layer overlap as a consequence of small pore radii and low electrolyte concentration. Overall, using the SMPNP model we gain insights into key performance-controlling parameters inside a catalytic nanopore. Furthermore, the model can be used to inform boundary conditions in larger-scale GDE models.