bluuebunny/crossref_metadata_2025 huggingface dataset:
Cu-Bx (X: N, CN, P) Composites for CO2 Electroreduction: Materials Vs. Gas Diffusion Electrode Characteristics
Authors: Pellumbi Kevinjeorjios , Smialkowski Mathias , Siegmund Daniel , junge Puring Kai , Apfel Ulf-Peter
Published: November 2022

The conversion of CO2 is an attractive strategy towards the mitigation of environmental pollution, and the production of bulk chemicals and fuels by renewables. In the field of CO2 electroreduction, copper constitutes the most versatile catalyst, being able to generate CO, C2H4, CH4, as well as alcohols and acids from CO2. Lately, research on Cu-based CO2 electroreduction has focused on two main topics: firstly, the operation under elevated current densities through the development of stable and selective gas diffusion electrodes (GDEs), and electrolyzers; secondly, the tuning of the selectivity of Cu-catalysts towards a specific product. Regarding the latter, common methods, include doping with other metals and heteroatoms, alloying, as well as creating electrode architectures consisting often of Cu/Ag and Cu/Zn structures.

Contrary to Cu, only a few heterogeneous electrocatalysts have shown the ability to generate more complex molecules beyond CO and HCOOH, such as hydrocarbons and alcohols. Among these catalysts, the chemically robust and synthetically scalable, boron phosphide (BP) has shown the ability to favor the production of CH3OH from CO2 under low current densities of ca. 2 mA cm-2.

Aiming to achieve a synergistic effect between Cu and BP, we herein investigate the role of electrode characteristics versus material properties in gas diffusion electrodes under industrially relevant current densities > 100 mA cm-2. Starting from GDE-properties, we report on the influence of the layer arrangement of Cu and BP on the surface of the GDL, their mixing ratio as well as the deposition method and cell type on the CO2 electroreduction. Furthermore, in order to elucidate the role of material properties towards deciding the product spectrum, we compared the activity of B-compounds with different structural characteristics, possessing cubic as well as hexagonal structures. Concretely, cubic boron nitride (c-BN), and phosphide (BP) as well as hexagonal boron carbon nitride (h-BCN), and hexagonal BN (h-BN) are evaluated in a series of Cu-based GDEs. Depending on the selected layer arrangement, material combination and mixing ratio we are able to steer the main CO2RR product to either CO, C2H4 or CH4 at 200 mA cm-2. Beyond Cu-BX GDEs, our results demonstrate that in the case of synergistic effects, material/electrocatalyst development and electrode/electrolyzer architecture must go hand-in-hand, providing important strategies towards the optimization of composite electrocatalysts.

Figure 1
(General Student Poster Award Winner - 2nd Place) Analyzing the Soret Coefficient Using Time Resolved Fourier Transform Infrared Spectroscopy (FTIR)
Authors: David Ashley Amalia , Silverman Micah , Hallinan Daniel
Published: November 2022

This study varies salt concentrations of lithium bis-trifluoromethanesulfonylimide (LiTFSI) in the block copolymer polystyrene-poly(ethylene oxide) (SEO), at different temperature gradients, analyzing the effect these parameters have on the magnitude of the Soret coefficient. The Soret Coefficient is the phenomena resulting in a concentration gradient via a temperature gradient. It is quantified by the ratio of thermal diffusion to mutual diffusion. The Soret effect can be utilized in thermogalvanic cells, by re-harvesting wasted heat from most power generating systems. Thermogalvanic cells, are a way to utilize a heat sink to create electrical energy, having the temperature gradient drive the system. Specifically, solid state polymer electrolytes are of interest in these cells as they offer benefits such as low flammability, high safety, and improved energy density, compared to common liquid electrolytes. Thus, application of the Soret effect in thermogalvanic cells is a clear way to greatly increase global energy efficiency, saving money for companies, and decreasing the global environmental footprint. To gain insight as to direction of diffusion in solid-state polymer electrolytes, and make this cell a reality, time resolved Fourier Transform Infrared spectroscopy (FTIR-ATR) measurements provide an unprecedented data accuracy for modeling. The FTIR makes the correlation between the infrared absorbance of the presented salt and its boundary concentration in the polymer through the Beer Lambert law, which has been proven true for salts in previous work. This technique overcomes many previous limitations to experimental techniques measuring the Soret Coefficient, making the FTIR-ATR an effective and repeatable instrument to use for collecting diffusion coefficients.
The Significance of Organometallic Complexes in the Photochemical Reduction of Cu2+ Onto Semiconductor Scaffolds
Authors: Rogers Charles Edward , Sheets Katey M , Keleher Jason J.
Published: November 2022

Metal-metal oxide nanoparticles (MMO-NP) show promise as an alternative to diffusive topical antibiotics as they are capable of slowly releasing metal ions upon contact-activated oxidation which promotes toxicity to prokaryotes. Modification of semiconducting nanoparticles with metals also has great relevance in terms of increasing the photocatalytic activity of the particles, which are inherently limited in practicality due to their large band gap energies. The use of semiconductor nanoparticles for the reduction of metal ions has been widely explored, however, more work needs to be done to make the reduction of metal ions like Cu2+ more facile. This work will focus on the mechanism and efficacy of incorporating Cu2+ into organometallic complexes for the photoreduction of Cu2+ on the surface of TiO2 and ZnO. The mechanistic contribution of bidentate complexes of Cu2+ in the complete reduction of Cu2+ will be explored. The implementation of L-serine (SER), L-arginine (ARG), and glucono-delta-lactone (GDL) as ligands will be observed. Initial results show that the coordination of Cu2+ into an organometallic complex provides an effective medium for the delivery of Cu2+ to the surface of TiO2. Spectroscopic analysis will be used to determine if the ligands contribute to the two-electron reduction via ligand to metal charge transfer (LMCT) or via non-covalent interactions that increase the effective concentration of Cu2+ at the nanoparticle surface. The surface modification of TiO2 will be observed post-reaction with scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDS) and atomic absorption spectroscopy (AAS) to measure copper content on the surface. Antimicrobial effectiveness will be characterized via Kirby Bauer testing as well as single cell optical imaging, with E. coli being the model microbe. Photocatalytic activity will be observed via the degradation kinetics of model pollutants. Preliminary results indicate that the addition of ligands greatly increased the yield of reduced copper at low pH and that there is some extent of control over the copper ion leaching as Kirby Bauer tests showed no zones of inhibition.
An Electrochemical Immunoassay System for Measuring Circulating Protein Biomarkers of Pediatric Soft Tissue Sarcoma
Authors: Addo Michael Kofi Darko , Antwi Ivy , Bishop Gregory
Published: November 2022

The combination of simple, inexpensive 3D-printed flow cells with electrochemical biosensors has recently emerged a promising strategy for detecting molecular biomarkers of disease. In this study, we report a multiplex electrochemical immunoassay based on pencil graphite electrode arrays, 3D-printed flow cells and magnetic bead bioconjugates for simultaneous detection of three biomarker proteins (cancer antigen 125 (CA-125), midkine (MK) and osteopontin (OPN)) linked to pediatric soft tissue sarcoma (PSTS). Magnetic bead bioconjugates are functionalized with large amounts of antibody and enzyme labels according to a previously reported strategy,1 pencil graphite electrodes are modified with gold nanoparticles and antibodies for specific capture of bioconjugate-labeled biomarkers, and 3D-printed flow cells to facilitate amperometric detection. Using this immunoassay platform, detection limits for CA-125, MK and OPN that are 100 times lower than those obtained using commercial enzyme-linked immunosorbent assay (ELISA) can be achieved. The combination of low-cost pencil graphite electrode arrays with the convenience of multi-labeled magnetic bead bioconjugates and simplicity of 3D-printed flow-cells results in a promising electrochemical biosensing strategy for biomarker proteins CA-125, MK, and OPN in human serum samples.

Reference

(1) Malhotra, R.; Patel, V.; Chikkaveeraiah, B. v.; Munge, B. S.; Cheong, S. C.; Zain, R. B.; Abraham, M. T.; Dey, D. K.; Gutkind, J. S.; Rusling, J. F. Ultrasensitive Detection of Cancer Biomarkers in the Clinic by Use of a Nanostructured Microfluidic Array. Analytical Chemistry
2012, 84 (14), 6249–6255. https://doi.org/10.1021/ac301392g.
Synthesis of Substituted Barium Ferrites and Hexaferrites and Their Electrochemical Characterization
Authors: Gómez Lara Kevin Steven , Morales Jimmy , Collazos Reina Jhon Jairo , Herrera Julian Hernández , Avendaño Alvaro J , Dector Andrés
Published: November 2022

Magnetic nanoparticle has been an attractive area of research in view of their unique physical and chemical properties. [1] In the field of electrochemistry, particularly electroanalysis, they are extensively used as functional materials due to their high surface area, mass transport, catalytic effect, and control over the local environment. Barium based ferrites have emerged as attractive materials of interest due to their interesting physical, chemical, magnetic and electrical properties. [2] Hexaferrite and ferrites such as barium ferrite are very important group of magnetic oxides and these are used in different technologies including sensors because of their specific properties such as low cost, corrosion resistance chemical stability and large magneto crystalline anisotropy. [3] However, the investigation of the effect by various other elements on the structure of hexaferrite and ferrite particles and its electrochemical properties remains the subject of popular research. In this work, mixed metallic oxides hexaferrite and ferrite were synthesized by sol–gel combustion route using glycerin as an adjuvant. [4] Their structure was confirmed by means of X-ray powder diffraction. Scanning electron microscopy were used to investigate the morphology of the sample and the vibrations of the functional groups were determined by Raman and IR-ATR spectroscopy. The electrochemical behavior of substituted hexaferrite and ferrite were determined by cyclic voltammetry using an Ag/AgCl electrode, platinum wire and a glass carbon electrode (GCE), as reference electrode, counter electrode and working electrode, respectively. The GCE was modified with mixed metal oxides obtained to analyze their electrochemical behavior.

Bibliographic

Xueli X, Wei S 2019 Materials Technology, 1-5

Kefeni, K.K.; Msagati, T.A.; Mamba, B.B. 2017, Sci. Eng. B. 215, 37–55

Valenzuela R, Magnetic Ceramics, Chemistry of Solid State Materials 4 serie. Cambridge (Great Britain): Cambridge University Press, 1994, p. 50

Sandra F. Basante-Delgado, Dalliver González-Vidal, Jimmy A. MoralesMorales, William A. Aperador-Chaparro, Jairo A. Gómez-Cuaspud, 2020 Phys.: Conf. Ser. 1541 012013
Understanding the Electrochemical Interactions of Coronavirus
Authors: Ramanujam Ashwin , Botte Gerardine G.
Published: November 2022

Coronavirus has become a household name over the past two years. Diagnostic tests have seemed to assist early identification and isolation of infected individuals affected by coronavirus, thereby curbing the spread of the disease. Although RT-PCR has been the gold-standard for diagnostic testing, its high turnaround time for results has led to several alternate biosensing technologies being employed for rapid Covid-19 screening. Electrochemical biosensors, being one of those technologies, has the advantage of being miniaturized for point-of-use, and producing rapid and highly sensitive results. Often, these alternate techniques involve the detection of an antigen (eg. spike protein) instead of the nucleic acid material. This leads to a compromise in the detection accuracy while improving the detection time and eliminating the need for amplification. Understanding the working principle of rapid antigen tests is essential for improving the accuracy. In this study, we shed light towards the interaction of coronavirus with our Ultra-Fast Covid-19 Diagnostic Sensor (UFC-19). UFC-19 is a nickel based electrochemical sensor that interacts with SARS-CoV-2 at very short times to produce current responses in a particular analysis window. Chronoamperometry is used for electrochemically characterizing the interaction between the electrocatalyst and hydrogen occupancies on spike protein. This reaction seems to occur at very short time span (~1 ms) as a result of local pH changes at the electrical double layer. UFC-19 can screen for coronavirus in saliva or water and can distinguish coronavirus current response from other viruses like HIV, Influenza or bacteria like E. coli. Although the response is specific to corona viruses, it is not specific to SARS-CoV-2. Hence, it is of utmost importance to selectively distinguish SARS-CoV-2 from other coronaviruses such as SARS-CoV, MERS-CoV or Human-CoV. The kinetics of these coronaviruses are studied using a rotating disk electrode to differentiate how their spike proteins diffuse and interact at the double layer causing pH change. There seems to be a correlation between the dissociation constants, pH changes and diffusion coefficients of the different corona viruses from our preliminary studies. Diffusion coefficients of these corona viruses could provide a possible insight into rate at which the interaction occurs leading a pathway for selective SARS-CoV-2 detection. This insight is key to engineer and improve the accuracy of UFC-19 for SARS-CoV-2 detection and to further extend this technology for other pathogenic organisms.
(Invited) U.S. DOE Initiatives Supercharging Advanced Battery Manufacturing Innovation
Authors: Suh Changwon
Published: November 2022

The Department of Energy’s Advanced Manufacturing Office (AMO) continues to invest in energy storage research, development, demonstration, and deployment (RDD&D) to help stakeholders improve efficiency, cut costs, and make materials, devices, and systems with superior performance. Despite recent promising advances, manufacturing capabilities are still necessary to meet the expected demand for energy storage as we move toward a clean energy economy. Strengthening the domestic manufacturing supply chains is also another important task to pursue in parallel.

AMO and the Vehicle Technologies Office (VTO) both funded projects through a Battery Manufacturing Lab Call to address capability gaps and engineering challenges for enhanced lithium-ion batteries, with a focus on de-risking, scaling, and accelerating adoption of new technologies through public-private partnerships. These projects successfully demonstrate how the advanced technologies are increasingly being used to solve battery manufacturing challenges. In addition, flow battery systems manufacturing projects funded by AMO are focusing on developing efficient, scalable manufacturing processes, and robust supply chains for flow battery system components.

In this talk, the status and accomplishments of the projects will be highlighted. In addition, there will be a robust discussion of a wide variety of AMO’s efforts in the context of technical and manufacturing challenges regarding scale-up and performance that still prevent the electrochemical energy storage community from achieving cost targets and commercial viability.
Measurement of the Heat Generation Rate of a Pouch Type Lithium-Ion Battery Using a Multifunctional Calorimeter
Authors: Hu Yang , Song Minseok , Garrick Taylor R. , Choe Song-Yul
Published: November 2022

Accurate characterization of the heat generation rate of lithium-ion batteries is critical for driving towards a cost-effective and efficient design of a thermal management system for various applications. Because of the increase in battery cell dimensions, as well as more aggressive operating conditions seen in the automotive industry, such as Direct Current Fast Charge (DCFC) and sustained driving under load, heat generation seen at the cell level must be considered as spatially non-uniform during operation. Proper design of the thermal management system requires measurement of the heat generation of the battery cell in both a lumped fashion for system sizing, as well as a distributed mode in order to tailor cooling appropriately to decrease local temperature extremes. Additionally, characterization of both the irreversible and reversible heat generation of the battery cell at various states-of-charge, temperatures, and states-of-life is required. Currently, few commercial calorimeters are available for the measurement of heat generation under dynamic conditions with a reasonable balance of accuracy and cost. In this work, we detail the development of a new calorimeter that allows for the measurement of the heat generation rate, determination of the irreversible and reversible heat generation, and rapid response time to capture dynamic cell responses.

References:

Minseok Song et al 2020 J. Electrochem. Soc. 167 120503

Yang Hu et al 2022 J. Power Sources 532 231350

Yang Hu et al 2021 App. Thermal Eng. 189 116709

Yang Hu et al 2020 Electrochimica Acta 362 137124

Figure 1
Quantification of Lithium Inventory Loss in Micro Silicon Anode Via Titration-Gas Chromatography
Authors: Sreenarayanan Bhagath , Bao Wurigumula , Meng Shirley , Tan Darren , Li Weikang , Bai Shuang
Published: November 2022

Enabling silicon as an anode material for LIBs has been largely impeded by the severe volume changes it undergoes during cell operation, causing continuous Li inventory loss . Therefore, It is important to understand and quantify various sources of capacity fade in order to design effective mitigation strategies. In this work, we used a method based on Titration Gas Chromatography (TGC) to show a non-linear volume expansion in µSi anode during the electrochemical lithiation process. The severe volume expansion towards the end of lithiation leads to the accelerated SEI formation and thus leading to the conductive pathway loss, which results in a large amount of trapped Li-Si alloy accumulation. This TGC method was also applied to study μSi anodes with two different binders namely: Sodium Carboxymethyl Cellulose (CMC-Na) and Polyacrylic Acid (PAA). The main reason for capacity loss for the anode with CMC-Na binder was the trapped Li-Si alloy, which was reduced by using a more mechanically robust PAA binder. The concept of State of Charge (SoC) control was also investigated in µSi-LFP full cells with both the binders by tuning the N/P ratios from 1.5 to 3. The results showed that binder robustness is important for mitigating the trapped Li-Si alloy accumulation in µSi anode. Additionally, the effect of particle size of active material on trapped Li-Si accumulation was also investigated using the TGC method

Figure: Cycle performance of µSi- CMC-Na-LFP full-cell with various N/P ratios (b) Cycle performance of µSi-PAA-LFP full-cell with various N/P ratios (c) TGC Data for Lithium inventory loss of full cell after 1st cycle for various N/P ratios (d) TGC Data for Lithium inventory loss of full cell after 10 cycles for various N/P ratios

Figure 1
In-Depth Analysis of the Substantial Effect of Fast Formation on Lithium-Ion Cell Characteristics
Authors: Witt Daniel , Bläubaum Lars , Baakes Florian , Krewer Ulrike
Published: November 2022

The formation of lithium-ion batteries is a crucial process step in battery production. Although it covers only the first few charging and discharging cycles, it impacts both the long-term degradation as well as the performance characteristics of the final cell. Commonly, formation times are on the order of multiple days due to relatively low C-rates. Although this prevents safety-critical lithium plating, research has shown that neither the slowest nor the fastest formation result into the best possible cell characteristics. [1]

To allow for a knowledge-based design of the cell formation process, detailed cell diagnostics including the characterization of the formed solid electrolyte interphase (SEI) are indispensable. However, the preparative effort for most experimental methods for SEI characterization like SEM or XPS is significant and will also require cell disassembly. An in-operando cell diagnosis can be realized with physicochemical modeling based on non-destructive dynamic electrochemical measurements. However, the dynamics of the SEI are commonly either modeled in a simplified way or the models are not designed for the simulation of various measurement types. To overcome these limitations, we extended the classic battery model from Doyle et al. [2] with a detailed SEI modeling. This finally allows to describe C-Rate and EIS data with the same parameter set (see Fig. 1a,1b), providing detailed insights into performance-limiting processes and their changes along cell aging. [3]

On the experimental side, we performed a broad formation study at different temperatures with different currents and current profiles, using small-scale three-electrode test cells. Fig. 1c) shows the discharge capacity for different formation procedures. Clearly, the performance significantly depends on the chosen formation conditions. The model-based cell diagnosis helps to shed light onto this interrelation. Surprisingly, we found that the bulk and interfacial properties of the SEI are not the root cause for the substantial differences in the cell’s fast charge/discharge capability. In fact, the effective transport properties in the anode electrolyte phase are driving the performance differences. Furthermore, the cathode reaction kinetics are affected by the chosen cell formation protocol. Ultimately, our experimental formation study in combination with the model-based cell diagnosis highlights that the cell formation process is not only about a stable SEI but also about minimizing the impact of reaction products from the SEI formation on the bulk electrolyte phase.

References:

[1] H. Mao et al. (2018) J Power Sources 402, 107-115

[2] M. Doyle et al. (1993) J Electrochem Soc 140 (6), 1526-1533

[3] D. Witt et al. (2022) Batteries Supercaps, 10.1002/batt.202200067

Figure 1
Recyling Mangosteen Shell Waste to Produce Activated Carbon Used As Electrode Materials Via a Sustainable Technique for Supercapacitor Applications
Authors: Kitenge Vianney Ngoyi , Manyala Ncholu , Tarimo Delvina , Oyedotun Kabir O.
Published: November 2022

Herein, we investigated and described a one-step combined carbonization/activation technique to produce high surface area activated carbon obtained from mangosteen shells (M-S). The synthesis was performed with various activating agents including potassium hydroxide, potassium carbonate, and hydrochloric acid. After microstructural analysis, an optimized mangosteen shell derived activated carbon (M-S AC) porous carbon with a large surface area of 2802.6 m2 g−1, a flower-like morphology, and a mesoporous arrangement was obtained. It also demonstrated excellent electrochemical performances in a three-electrode measurement with a specific capacitance of 298.13 F g -1 at a specific current of 0.5 A g -1 and a potential window of -0.9 V using 2.5 M KNO3 as the electrolyte. An assembled symmetric (M-S AC+//M-S AC-) supercapacitor device using 2.5 M KNO3 presented a sustaining capacitance of 31.5 Fg−1 at 0.5 A g-1, an energy density of 11.5 Wh kg-1 which relates to a power density of 0.4 kW kg−1 at 0.5 Ag-1. A second assembled symmetric M-S AC+//M-S AC- supercapacitor device using ionic liquid electrolyte (EmiFSI) demonstrated a specific energy of 30.51 Wh kg−1 and specific power of 0.7 kW kg-1 at 0.5 Ag-1.The study established the potential use of mangosteen shell as an excellent precursor to produce a high surface area activated carbon at a lower production cost and highlighted the advantage of using EmiFSI electrolyte for high-energy supercapacitor.
(Digital Presentation) Electrochemical Sodiation Mechanism in Magnetite Nanoparticle-Based Anodes: Understanding of Nanoionics-Based Sodium Ion Storage Behavior of Fe3O4
Authors: Islam Mohammad , Bouldin Jared , Yang Junghoon , Han Sang-Don
Published: November 2022

Electrochemical ion storage behaviors of Fe3O4 nanoparticles, as a representative transition metal oxide for an environmentally benign and low cost anode for a sodium ion battery, are thoroughly investigated through a combination of electrochemical analysis and diagnostics of Fe3O4 electrode cells, X-ray based and spectroscopic analysis of material structure evolution as functions of depth of discharge (DoD) and state of charge (SoC), and first principle modeling. The gravimetric capacity is found to be 50 mAh/g for bulk Fe3O4 (50 nm average crystallite size) and 100 mAh/g—about a tenth of the theoretical prediction for complete conversion—for Fe3O4 nanoparticles (8.7 nm average particle size), respectively. A fundamental and mechanistic study of material evolution as functions DoD and SoC shows that Fe3O4 does not allow electrochemical incorporation of Na+ ions into the empty cation positions of the inverse spinel structure, leading to our assertion that electrochemical intercalation of Na+ ions to conversion of Fe3O4 anode in sodium ion batteries is nonviable. Density Functional Theory investigation points to the impracticality of the intercalation of Na+ ions into Fe3O4, and further validates our experimental findings. We propose several possible mechanisms corresponding to the observed low capacity, including formation of solid electrolyte interphases with unfavorable properties, adsorption of Na+ ions onto surfaces of nanoparticles and/or at hetero-interfaces in Fe3O4 composite electrodes in a NaPF6-based electrolyte system.
Highly Conductive Sulfide Solid-State Electrolytes for All-Solid-State Li Battery
Authors: Yu Zhaoxin , Lu Dongping
Published: November 2022

The All-Solid-State Battery (ASSB) Is a Promising Next-Generation Energy Storage Technology for Both Consumer Electronics and Electric Vehicles Because of Its High Energy Density and Improved Safety. Sulfide Solid-State Electrolytes (SSEs) Have Merits of Low Density, High Ionic Conductivity, and Favorable Mechanical Properties Compared to Oxide Ceramic and Polymer Materials. However, Mass Production and Processing of Sulfide SSEs Remain a Grand Challenge Because of Their Poor Moisture Stability. Here We Report a Reversible Surface Coating Strategy for Enhancing the Moisture Stability of Sulfide Sses By Using Amphipathic Organic Molecules. an Ultra-Thin Layer of 1-Bromopentane Is Coated on the Sulfide SSE Surface (e.g., Li7P2S8Br0.5I0.5) Via Van Der Waals Force. 1-Bromopentane Has More Negative Adsorption Energy with SSE Than H2O Based on First-Principles Calculations, Thereby Enhancing the Moisture Stability of SSE Because the Hydrophobic Long-Chain Alkyl Tail of 1-Bromopentane Repels Water Molecules. Moreover, This Amphipathic Molecular Layer Has a Negligible Effect on Ionic Conductivity and Can be Removed Reversibly By Heating at Low Temperatures (e.g., 160°C). This Finding Opens a New Pathway for the Surface Engineering of Moisture-Sensitive SSEs and Other Energy Materials, Thereby Speeding up Their Deployment in ASSBs.
Carbonized Bacterial Cellulose Decorated with ZIF-8 Derived Iron Single-Atom Catalyst Nanocages As a Cathode Host for Lithium-Sulfur Batteries
Authors: Lin Xueyan , Wang Shu , Wang Bin , Fan Zhaoyang
Published: November 2022

Li-S chemistry is regarded as promising next-generation battery technology. However, its complex redox process and long-chain lithium polysulfides shuttling are hindering the development of practical Li-S battery technology. Various electrocatalysts are being investigated to address the problem by expediting reaction kinetics. Here we report Fe single metal atom catalyst (Fe-SAC) used in the sulfur cathode of Li-S batteries.

Fe-SAC is synthesized using a modified metal-organic framework (MOF)-based approach, in which the low vapor pressure Fe element substitutes Zn during pyrolysis of ZIF-8 to attain Fe-N4 moieties by being coordinated with four substitutional nitrogen atoms in the graphene lattice. A freestanding 3D structure with Fe-SAC-functionalized carbon nanocages linked by a carbon nanofiber network is applied as the sulfur cathode scaffold. Here the nanocages are derived from Fe-doped ZIF with Fe-N4 SAC moieties embedded on the inside and outside surfaces. The carbon nanofiber network is derived from the carbonization of bacterial cellulose.

We report several methods for assessing Fe-SAC catalytic function on sulfide redox reactions for the prepared electrode in cells with lithium polysulfides electrolytes. Electrochemical studies compare the performance of the nanostructured electrodes with or without Fe-SAC to confirm the catalytic effects in improving the Li-S battery performance. Accordingly, the prepared composite cathode delivers a high initial capacity of 1338 mAh/g at 0.1C and excellent rate capability at 2C with a reversible capacity of 840 mAh/g.
Perfluoroalkylated Catholyte Harnessing Multiple Fluoride Bond Breaking for Lithium Primary Batteries
Authors: Gao Haining , Yoshinaga Kosuke , Swager Timothy M. , Gallant Betar M.
Published: November 2022

Lithium primary batteries, with theoretical energy densities 3x higher than the rechargeable systems, are critical for applications where recharging is impossible or impractical, such as medical implants, unmanned vehicles, and remote monitoring. The current energy leader among commercial primaries is the Li−carbon monofluoride (CFx) battery, which has the highest theoretical energy density (2180 Wh/kgCFx) and up to 800 Wh/kg achieved in packaged cells. The solid CFx (0 < x ≤ 1.3) particles enable excellent safety and shelf stability, but also result in limited rate capability due to low electronic conductivity. Unfortunately, despite the increasing demand for high-energy Li primaries, the field is maturing with few fundamental innovations in cell chemistries in the past 40 years. To design battery chemistries that can surpass the energy of Li−CFx cell, herein, we examined the possibility to conduct multi-electron carbon reduction in high F content perfluoroalkyl groups (RF = −CnF2n+1, with F/C ratios of x>2) using liquid phase reactants. First, using liquid perfluoroalkyl iodides (CFI) as a model system, we investigated the governing factors for C−F bond redox, including supporting solvent viscosity, CFI chain length and concentration, discharge rate, and temperature. Up to 8 e− transfer per CFI (>1.3 e− per C, or 8/13 available F) is achievable with low reactant concentrations (0.1 M) and rates (20 μA/cm2). CFI catholyte sees challenges at high reactant concentrations and/or rates, as premature cell termination caused by deactivation of intermediates was observed. Therefore, to address this issue, we examined multiple handles in molecular structure to further tune the C−F bond activity. By replacing the I-ligand in CFI with an aromatic structure, the obtained fluoro-aromatics demonstrate close-to-full defluorination of RF group, yielding up to 15 e− (out of 17 available F) transfer per molecule, and attractive gravimetric energies of up to 1785 Wh/kgfluoro-aromatic, at high potentials (up to 2.6 V vs. Li/Li+) and concentrations (up to 1 M). Additionally, the voltage compatibility of the fluoro-aromatics with CFx enabled the hybridization of the catholyte and solid cathode in one cell. The hybrid cells provide opportunity to maximize the active material loading at cell-level, showing strong potential to further improve the energy densities over existing battery systems.
(Digital Presentation) Aqueous Zn Batteries and Capacitors Working Under Extreme Conditions
Authors: Wang Xiaolei
Published: November 2022

Aqueous zinc-based energy storage devices hold great promise for grid-level energy storage yet are challenged by dendritic growth and low Coulombic efficiency under both normal and extreme conditions. In the past years, we have developed Zn batteries and capacitors working under extreme conditions through engineering electrode, electrolyte, and binder. The first project is the development of Zn-free polymer anode that enables ultrafast rates (100 A g-1), ultralong life (1 million cycles), and ultrahigh-loadings (50 mg cm-2) through DFT calculation, polymer preparation, and electrolyte optimization. The optimal polymer possesses suitable electronic structure and a large π-conjugated structure and its storage mechanism involves reversible Zn2+/proton co-storage at the carbonyl site. The polymer-based full cells demonstrate ultrahigh power densities and ultralong lifespans, far surpassing those of corresponding Zn-metal-based devices. The second project is the making of ultrafast, stable, high-loading and wide-temperature zinc ion supercapacitors through the incorporation of activated carbon (AC), aqueous binder, and concentrated electrolyte. AC exhibits large surface area, hierarchical porous structures, and abundant heteroatom dopants, aqueous binder enhances electrode-electrolyte wettability enabling high-mass-loading electrode, and concentrated electrolyte gives high Zn stripping/plating efficiency, high ionic conductivity as well as suppressed hydrogen bonding interaction in water realizing ultralow frozen temperature. Three keys combined unlock unprecedented ZICs with a large capacitance of 436 F g−1 (capacity: 200 mAh g−1), ultrahigh rate up to 200 Ag−1, ultralong cycles (0.3 million), ultrahigh loadings (10 mg cm−2) under lean electrolyte (8.8 µL mg−1), and wide-temperature operation (-60∼60 °C), leading to a maximal energy density of 134.8 Wh kg−1 and power density of 118.4 kW kg−1. A proton/Zn2+ ion co-interaction mechanism was revealed in the AC electrode. With low cost and extreme functionalities, this work opens an avenue towards practical supercapacitors beyond normal conditions.
A Precision Polyanion for High Performance Lithium-Ion Transport in Polymer Blend Electrolytes
Authors: Blatt Michael P. , Hallinan Daniel , Kennemur Justin , Kim Kyoungmin , Nguyen Nam
Published: November 2022

A novel precision single ion conductor with an N-((trifluoromethyl)sulfonyl)phenylsulfonimide lithium salt covalently bound to every fifth carbon of a polyethylene backbone, p5PhTFSI-Li, was synthesized via post polymerization modification. The conversion to a trifluoromethanesulfonimide (TFSI) anion from the parent polymer bearing a phenylsulfonate anion was highly efficient (~90%) as determined by 19F-NMR analysis and corroborated through other spectroscopic methods. The bulky and flexible TFSI anion led to a reduced and observable glass transition temperature of ~199 °C and an improved thermal stability up to ~375 °C. Blending of p5PhTFSI-Li with poly(ethylene oxide) at various compositions was performed to investigate electrochemical performance and transference numbers with respect to the lithium electrode using a combination of impedance and polarization methods. At 90 °C, this system displayed high conductivity up to 2.00 X 10-4 S cm-1 and transference numbers were near unity independent of temperature, making this system highly competitive with other polyanion/polyether blend electrolytes. Investigations into the complex miscibility and phase behavior of these blends at various compositions was also probed by a combination of microscopy and differential scanning calorimetry.
Understanding the Effects of the Mixing Processes on the Performance of NMC-LMO Blend Electrodes Made By a Dry Electrostatic Spray Deposition Process
Authors: Uzun Kubra , Wang Ming , Huang Xiaosong , Frieberg Bradley , Hu Jiazhi , Cheng Yang-Tse
Published: November 2022

Improving the manufacturing process of making lithium-ion batteries (LIBs) is a key to further decreasing the cost and expanding the market of LIBs for many applications, especially for electric vehicles. Since electric vehicles require durable, sustainable, and cost-effective battery systems for their continued enlargement, advanced manufacturing processes of LIBs need to be investigated. The conventional wet slurry operation for LIB electrode manufacturing imposes several limitations on cost and performance mostly due to solvent usage. The drying process for the evaporation and recovery of organic solvent requires the use of unwanted solvents that do not contribute to the final product, thus consuming energy. If solvent evaporation is not controlled well, issues such as binder migration, segregation, and cracking of the electrode can occur, affecting the performance of the battery. Therefore, using a solventless dry process for electrode manufacturing has the potential to reduce the cost and environmental impact by eliminating solvent usage.

In this work, electrostatic spray deposition (ESD) without the use of a solvent is investigated for manufacturing thick NMC811/LMO electrodes. Comparing two different dry powder mixing methods, we showed that dry powder mixing prior to ESD has a significant effect on the electrode microstructure and, consequently, its performance. Electrodes made by ball mill mixing retained better discharge capacity, which was attributed to the low charge transfer resistance and improved ionic conductivity due to porous conductive pathways formed between and on the active material particles. High speed mixing, on the other hand, caused dense layers of binder and conductive agent agglomerates, limiting the contact area of the electrolyte with active materials and increasing the resistance.
A Facile and Scalable Fabrication of High-Performance Flexible Laser-Induced-Graphene Micro-Supercapacitors Using Ultrafast Pulse Laser
Authors: Lee Yeong A , Jang Kyuyeon , Yoon Hana
Published: November 2022

The rapid growth of wearable and portable electronics has promoted the development of microscale energy storage devices. Among these devices, microsupercapacitors (MSCs) have emerged as promising flexible energy storage devices owing to their high power density, high charge/discharge rate, and long-term cycling stability.[1,2,3] Most synthesis method of graphene electrodes for flexible MSCs rely on complex processes or chemical synthesis routes, such as photolithography, mechanical exfoliation, or chemical and thermal reduction. On the other hand, laser direct writing are a simple, design-flexible, highly scalable, and cost-effective method for graphene production. Here, we developed two types of green flexible microsupercapacitor using femtosecond pulse laser. First, we report a high performance sticker-type flexible microsupercapacitor using highly swollen reduced-graphene oxide electrodes fabricated by an ultrashort pulse laser.[4] Second, we demonstrate the direct fabrication of highly conductive, intrinsically flexible, and green microelectrodes from naturally fallen leaves in ambient air using femtosecond laser pulses without any additional materials.[5] Both types of MSCs not only showed excellent electrochemical performance, but were confirmed to work as a power supply for various applications such as LED and thermometer. Therefore, our flexible microsupercapacitors can be widely applied as energy-storage devices for flexible/wearable electronics.
How a Li-Ion Battery Talks: Electrochemical and Mechanical Behaviors of the Battery Using in-Operando Acoustic Emission
Authors: Hoq Mahmudul , Shin Hosop
Published: November 2022

Degradation of a Li-ion battery involves multiple mechanisms that are strongly coupled with each other. Th highly coupled nature of degradation mechanisms makes it complex to understand dynamic electrochemical and mechanical behaviors of the battery. In-operando acoustic emission (AE) technique can provide fundamental insights into the dynamic behaviors of the battery during operation. However, it remains unclear how different types of AE signals are linked to electrochemical and mechanical events occurring inside the battery. Here, we show our efforts to develop an in-depth acoustic analysis to correlate different types of AE waveforms with electrochemical and mechanical phenomena of the battery using a commercial, used battery pouch cell. The hits from the AE phenomena were analyzed using the waveforms and their Fast Fourier Transform (FFT) to get the frequency spectra of the AE sources. Our results show how particle- and electrolyte-level fracture, gas generation, intercalation-induced stress processes are linked to different types of AE hits.
Analysis of Mechanical Properties and Electrochemical Behavior of Li-Ion Secondary Batteries According to Particle Size of Silicon Anode
Authors: Yang Min-Ji , Shim Jae-Hyun , Park Jeong-Yeon , Park Jae-Wan
Published: November 2022

Li-ion secondary batteries have been applied to various electronic devices since Sony released a lithium secondary battery using hard carbon as an anode in 1991. The market for large secondary batteries is gradually expanding and moving forward. And although high energy density, cyclability, and stability are required for use in various applications at this time, the currently commercialized graphite anode is facing the limit of theoretical capacity (LiC6, 372 mAh/g).

While research on next-generation anode materials is underway to increase the energy density of lithium secondary batteries, silicon has a high theoretical capacity close to 4000 mAh/g, attracting attention as an anode for next-generation lithium-ion batteries. However, the capacity retention rate is low due to the huge volume change and low electrical conductivity that occur during charging and discharging of silicon.

In order to solve this problem, many studies are being conducted, such as a) making a silicon-sized structure into a nano-scale and porous structure, b) oxidizing silicon, and c) a composite with a carbon material. Among them, much attention has been paid to improving the electrochemical performance of a silicon-based anode by designing a structure by fabricating silicon in a nano size. Compared to conventional silicon materials, nano-sized silicon was able to better withstand the stress caused by volume expansion during charging/discharging in the nano-surface-to-volume ratio. As a result, intergranular cracking can be limited, thereby improving cycle stability and maintaining high capacity. The particles can shorten the diffusion path of lithium by providing a stable electron and Li-ion transport path, and can provide increased rate-limiting properties and reduced resistance.

In this study, the effect of the manufactured silicon grain size on the mechanical and electrochemical properties of the Li-ion secondary battery was studied by various analytical methods.
Battery Health Retention from Thermal Runaway Suspension
Authors: Zhang Liwen , Liu Lu , Zhao Peng
Published: November 2022

With growing applications of Li-ion batteries in ground transportation and energy storage systems, thermal runaway of Li-ion batteries has become a major concern for energy and public safety. In this work, we come up with a strategy to suspend thermal runaway and meanwhile retain the electrochemical performance of the battery. We first analyzed the temperature and voltage evolution of commercial LFP 18650 cells during thermal runaway test following the standard heat-wait-seek strategy in an accelerating rate calorimeter (ARC). It is found that the voltage signal has a sudden drop corresponding to a similar temperature of 135 ℃, before the occurrence of thermal runaway. Thermal runaway suspension experiment is conducted by activating cooling when desired voltage and/or temperature signal is reached. It is observed that thermal runaway suspension from the voltage signal fails to prevent the battery from further damage. For thermal runaway suspension at the temperature signal 130 ℃, batteries are successfully saved regardless of fast liquid N2 cooling, or slow cooling using N2 gas. Further EIS testing shows that the batteries retained from thermal runaway suspension have increased bulk resistance while polarization resistance remains unchanged. The cycling performance of the saved batteries has demonstrated identical voltage but reduced capacity by around 20%. This research can provide useful guidance on thermal runaway prevention and health retention of Li-ion batteries.
A Study on the Cathode Materials Recovery Process Using Various Wet Chemistry
Authors: Kang Julgi , Kim Whanug , Lim Hong-Woo , Park Sangho
Published: November 2022

Demand for lithium-ion batteries (LIBs) has increased dramatically over the years due to the rapid market expansion of electric vehicles. Current commercial lithium ion batteries mainly contain nickel, cobalt, manganese metal oxides, lithium, phosphates, aluminum, copper, graphite, organic electrolytes and other chemicals. Therefore, the recycling and reuse of used lithium-ion batteries at the end of their useful life are of great interest by many researchers. However, due to the high energy density, high safety and low price of lithium-ion batteries, the difference and variety are large, which poses great difficulties in recycling waste lithium-ion batteries. Lithium ion batteries recycling typically involves both physical and chemical processes. Physical processes typically include pretreatment and direct recovery of electrode materials. These processes typically include decomposition, crushing, screening, magnetic separation, washing, heat treatment, etc. As shown in Figure 1, chemical processes can generally be divided into pyrometallurgical and hydrometallurgical processes which include leaching, separation, extraction and chemical/electrochemical precipitation. Recently, recycling technologies for lithium secondary batteries through a direct regeneration process have been attracting attention. Directly regeneration technique has the advantages of short recovery route, low energy consumption, eco-friendly compared to pyrometallurgical and hydrometallurgical processes. In order to recover the cathode active material from the separated electrode plate, a process for separating the PVDF binder and the cathode active material is required. In general, N-methyl-2-pyrrolidone (NMP) is the most common solvent for the manufacture of cathode electrodes in the battery industry. Although ~99% of the solvent used in electrode manufacturing is recovered, it is however limited in several countries due to negative environmental impacts.

In this study, the cathode materials were separated electrode from used lithium ion cell using various wet-chemistry. Chemical, structural, and electrochemical characteristics of the cathode materials and substrate were investigated.

Figure 1