bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigating the Moisture Sensitivity of Nickel-Rich Cathodes in Lithium-Ion Battery Production: Implications for Production Atmospheres and Cost Reduction
Authors: Lechner Maximilian , Wölfl Simon , Putz Elena , Daub Rüdiger
Published: December 2024

Nickel-rich cathode materials are considered promising for enhancing lithium-ion battery performance by enabling higher energy densities. However, their sensitivity to humid ambient conditions requires stringent production atmospheres, such as dry rooms, leading to significantly increased costs and energy consumption. This study investigated the storage stability of a surface-treated nickel-rich cathode (≥ 90 mol% nickel) under industry-relevant conditions to assess necessary atmospheres and the impact of short-term moisture exposure on material and cell performance. Calendered and non-calendered cathodes were manufactured in a dry room atmosphere with a dew point of −60 °C and subjected to elevated dew points of up to −22 °C and ambient atmosphere (dew point ≈ 5 °C). Analysis of formed impurities revealed that calendered electrodes displayed higher sensitivity to carbonate formation at elevated dew points. Cycling of single-layer full-pouch cells demonstrated that carbonate surface impurities, primarily present on electrodes stored in ambient atmosphere, contributed to lower energy efficiencies during formation. However, no significant difference in cell performance was discernible over prolonged cycling, suggesting potentially reduced dry room requirements. These findings hold significance for cell manufacturers aiming to mitigate production costs and energy consumption, while optimizing the environmental footprint of high-performance battery cell production.
A Guide to Choosing Polymers for Use in Lithium-Ion Cells
Authors: Adamson Anu , Abeysooriya Shanika , Johnson Michel B. , Boetticher Tom , Dahn Jeff R. , Metzger Michael
Published: December 2024

Every commercial lithium-ion cell made by winding or stacking electrodes uses tape to secure the jelly roll. Recently, it has been shown that lithium-ion cell jelly roll tape is often made out of polyethylene terephthalate (PET)1 and can dissolve into dimethyl terephthalate (DMT), a redox shuttle capable of inducing self-discharge unless effective electrolyte additives are present.2

This is due to ester bonds in PET that are susceptible to methanolysis via methanol and lithium methoxide. that are created in situ during battery operation from dimethyl carbonate (DMC), a ubiquitous solvent used in lithium-ion battery cells’ electrolytes. Effective electrolyte additives suppress the production of methanol and lithium methoxide from DMC, reducing the depolymerization of PET. However, the quantity of electrolyte additives used in commercial cells is low (1-3 wt%), and it has been shown that when ≤2 wt% of vinylene carbonate (VC) is used, most of it will be consumed during the first 200 h of operation.3 Thus, PET and any other polymer with a similar structure could become susceptible to methanolysis over long-term cycling.

Other polymers with a similar chemical structure to PET are also often used in battery manufacturing. Examples include polybutylene terephthalate (PBT) or polyethylene naphthalene (PEN), used in cylindrical cell gaskets4 or metalized polymer current collectors5–7, respectively. Due to their chemical structure being similar to PET, it is reasonable to assume that these polymers might also be susceptible to depolymerization during battery operation, if no effective additives are used. However, in these two use cases, the risk of depolymerization does not only affect self-discharge but also cell safety. If a cell gasket or current collector dissolves during battery operation, this could lead to serious battery safety hazards, e.g., leaks or internal shorts.

This study investigates the chemical stability of the most common polymers used in inactive components of commercial lithium-ion cells, e.g., pouch foils, adhesive tapes1, separators8, gaskets4, and metalized polymer current collectors5–7. The chemically stable and safe polymers to use in batteries are shown. In addition, the potential hazards of using chemically unstable polymers are demonstrated, and possible alternatives for battery manufacturers are proposed.

References

A. Adamson et al., Nat. Mater. (2023) https://www.nature.com/articles/s41563-023-01673-3.

S. Buechele et al., J. Electrochem. Soc., 170, 010511 (2023).

R. Petibon, J. Xia, J. C. Burns, and J. R. Dahn, J. Electrochem.
Soc., 161, A1618–A1624 (2014).

H. Kondo and T. Yamada, (2000) https://patents.google.com/patent/US6025091A/en.

https://metamaterial.com/solutions/battery-materials/.

https://soteriabig.com/technology/.

http://www.dupontteijinfilms.com/.

S. S. Zhang, Journal of Power Sources, 164, 351–364 (2007).
Impact of Sodium Carboxymethylcellulose Binder on the Performance of Lithium-Ion-Batteries for Industrially Relevant Anode Formulations
Authors: Keim Noah , Bauer Werner
Published: December 2024

To change the solvent in LIB electrodes to water, a water-based polymer binder has to replace the current PVdF binder. This led to Sodium Carboxymethylcellulose (NaCMC) being introduced as a water-soluble binder for LIBs. Due to NaCMC creating a weak connection with the current collector, usually, another additive like SBR rubber is usually added to increase adhesion. Nevertheless, NaCMC dominates the properties of the slurry and influences the structure of the final electrode decisively. Combining the multitude of functionalities of the NaCMC with it being produced from the most abundant polymer in the world, it creates a highly attractive binder, also from an industrial point of view. However, despite widespread use, there is only limited knowledge on how the NaCMC influences key battery properties and battery performance.

The objective of this research is to provide valuable insights into optimizing the composition of lithium-ion battery electrodes for enhanced energy storage and cycling stability, based on a better understanding of the influence of NaCMC. Especially, the influence of varying properties of the NaCMC, like degree of substitution and molecular weight are explained in more detail, which were analysed via adhesion strength testing, Karl-Fischer titration, electrical resistance and potentiostatic cycling. Finally, the influence of the varying NaCMC properties on the battery performance and SEI formation was investigated with post-mortem liquid NMR.
How Binder Decomposition May Influence the Performance of High-Capacity Silicon Electrodes
Authors: Mennel Jason , Chidambaram Dev
Published: December 2024

Silicon has been one of the most investigated electrodes to replace graphite, with having over ten times the theoretical capacity of graphite at 4200 mAh/g vs 372 mAh/g, respectively. While silicon promises to be a cheap, abundant, alternative, it’s use imparts a host of challenges before wide-spread commercialization can be adopted. Silicon expands several times it’s original size upon lithium insertion, which not only compromises structural integrity of the electrode itself, but cracks the adjacent solid-electrolyte interface layer, causing SEI stability to fluctuate. The methods adopted to overcome this volume expansion have been numerous, from decreasing silicon particle size to nanoscale, to creating nanowires, to nanotubes, that expand inward yet protect the outward facing SEI layer. The binder component in the original slurry is an important ingredient that aids in adhesion to the current collector as well as particle to particle adhesion. A common aspect of slurry composition is that binders are typically on the order of 10-20% by mass of all slurry components. Various binders have been explored for use with silicon, including the common polyvinylidene fluoride (PVDF) and polyvinylpyrrolidone (PVP). Recent literature has also highlighted that binders such as carboxymethyl cellulose (CMC) and polydimethylsiloxane (PDMS) can significantly improve performance over traditional binders when used with silicon electrodes. Another common method for enhancing silicon performance is by using a metal additive such as tin or copper, in small 1-2% by mass amounts. In the case of copper additive, a desired Cu3Si phase has been noted to improve performance and is obtained once the casted film is heat treated at 700°C. When heat treating a film to such high temperatures, traditionally, the nature of the binder is assumed to be burned off, or converted to some miniscule amounts of carbon, as all polymers carbonize around 400°C. Our investigation of increasing capacity of silicon electrodes at low temperatures has shown that the nature of the binder in fact does play a role in cell performance, even after the binder has carbonized through the heat treatment step. We have compared the traditional PVDF and PVP binders in full cells with lithium metal and an ether-based electrolyte, with the PVDF binder actually demonstrating significantly improved capacity over PVP at both room temperature and -20°C through long cycle life testing. The resultant cells using PVDF binder maintain over 1000 mAh/g capacity after 100 cycles at room temperature and 250 cycles at -20°C.
High Throughput Screening of Disordered Rocksalt Type Overlithiated Anode
Authors: He Yufang , Ouyang Bin
Published: December 2024

Rechargeable lithium-ion batteries with high energy density and fast-charging capability are vital for commercial application. Disordered rocksalt-type materials, characterized by overlithiation (cation/anion ratio > 1.0 due to additional lithium insertion), have emerged as promising candidates for high-rate and low-voltage anodes. Motivated by the already reported Li3+xV2O5 (0≤x≤2) anode, an exhausted search among all potential redox center as anodes have been performed with high throughput density functional theory (DFT) computations. A comprehensive search among all potential redox centers for anodes was conducted. In total, 23 redox centers from the periodic table were systematically evaluated for their stability, average voltage, electronic conductivity, and volumetric change during cycling. Potential overlithiated DRX anodes, comparable to the state-of-the-art Li3+xV2O5 (0≤x≤2) anode, will be showcased. Additionally, compositional design principles will be outlined, derived from data mining the high-throughput DFT data.
(Invited) Dry Electrode Technologies Toward High Energy Density and Low-Cost Lithium-Ion Battery
Authors: Choi Junghyun , Kim Patrick Joohyun , Lee Dongsoo
Published: December 2024

The electric vehicle (EV) market has grown very rapidly to meet the demand for net-zero carbon emissions in the transportation sector. The rapid growth of EVs is primarily attributed to the technological advances in lithium-ion batteries, making them the most promising energy storage devices due to their outstanding electrochemical performance. In recent years, the lithium-ion battery industry has made attempts to achieve price and driving range parity between electric vehicles and internal combustion vehicles. Significant efforts have been devoted to developing electrode processes as well as active materials in order to achieve low-cost and high-energy-density lithium-ion batteries. Particularly, the adoption of thick film electrodes is an effective way to increase both energy density and cost efficiency by reducing the amount of inactive materials, such as current collectors, separators, and cell components. In this presentation, we introduce the dry electrode technology to achieve ultra-thick film electrode. Dry electrode technology has the potential to provide a breakthrough in achieving higher loading levels and electrode densities. Moreover, the distribution of binders in dry electrodes does not impede lithium-ion transport, unlike wet electrode binders such as PVdF. Due to these synergistic effects, dry electrode-based electrodes have achieved ultra-high loading levels with lower resistance compared to wet-based electrodes. Additionally, dry electrode technology on the anode side has limitations due to the low low lowest unoccupied molecular orbital level (LUMO) level of the PTFE binder, resulting in side reaction during lithiation. This phenomenon significantly worsens battery performance, affecting factors such as initial Coulombic efficiency and cycle life. We suggest an effective strategy to mitigate the side reactions of dry-electrode technology.
Surface and Bulk Stabilization of Silicon Anodes Via in-Situ Formation of Li-M-Si Zintl Phases Using Multivalent Cation Additives
Authors: Park Sohyun , Wang Evelyna , Key Baris , Dogan Fulya
Published: December 2024

Silicon is drawing attention as the upcoming anode material for the next generation of lithium-ion batteries due to its higher capacity compared to commercial graphite. However, silicon anions formed during lithiation are highly reactive with binder and electrolyte components creating an unstable SEI layer and limiting the calendar life of silicon anodes. In this study, the reactivity of lithium silicide and the formation of unstable SEI layer is mitigated by utilizing the use of a mixture of Ca and Mg multivalent cations as an electrolyte additive for Si anodes to improve their calendar life. Ca and Mg ions in the electrolyte diffuse into silicon particles forming relatively thermodynamically stable quaternary Li-Ca-Mg-Si Zintl phases with less chemical reactivity, in an in-situ fashion, stabilizing the bulk. Ca and Mg cations also react with the F anions in the electrolyte, forming a layer of nanocrystalline CaF2 and MgF2 that is closely coated around the silicon particles. The CaF2-enabled new SEI is strong and dense, which effectively protects the silicon core from side reactions, leading to lower capacity decay after calendar aging at high voltage. To understand the mechanism of ternary/ quaternary Zintl phase formation and its dynamics upon lithiation/delithiation, high-resolution solid-state 7Li and 29Si nuclear magnetic resonance (NMR) are utilized to directly probe the local Li and Si environments on Si electrodes harvested from coin and pouch cells at various states of (de)lithiation. The effect of multivalent cation additives on bulk and surface of aged silicon anodes was studied by multiple structural characterization techniques such as Electron Microscopy, HRXRD, ex situ and operando solid-state NMR. The results show that the electrodes that are gone through cycling and calendar aging with multivalent cations tended to have less cracking on the electrode surface, less lithium trapping in the bulk and the presence of mixed cations enhances cation migration and formation of quaternary Zintl phases stabilizing bulk and forming a more stable SEI in comparison to baseline electrolytes.
Lithium Sulfate Coating of Co-Free, Li-Rich Layered Oxide Cathode for Improving Electrochemical Performance
Authors: Moon Jung Hyeon , Kang Hyeonmuk , Hwang GyuSeong , Lee Junho , Shin GeunHyeong , Cho EunAe
Published: December 2024

In the continued evolution toward high-performance lithium-ion batteries, cobalt has presented itself as a major obstacle due to its price, toxicity and supply. Thus, Co-Free, Li-rich Layered Oxide Cathodes (CF-LLC) have become a promising cathode for their exclusion of cobalt and high theoretical capacity. Nevertheless, CF-LLC suffers from issues such as sluggish kinetics, lowered early capacity and voltage fade due to structural degradation. This is due to the increase in cation mixing resulting from the absence of cation-ordering cobalt. To mitigate this, a pre-lithiation sulfate coating of the cathode carbonate precursor was implemented; which upon lithiation, presents a Li2SO4 coated CF-LLC (S-CF-LLC). The Li2SO4 coating prevents the agglomeration of primary particles during lithiation leading to a smaller average primary particle size. Hence, the surface area is increased and the Li diffusion pathways are shortened, leading to increased Li diffusivity during deep charging/discharging. The coating also prevents transition metal (TM) dissolution by acting as a protective barrier against HF attack from the electrolyte. The S-CF-LLC was successfully synthesized using a hydrothermal synthesis method with a wet chemical coating step and the synthesis was confirmed using XRD, SEM, XPS, ATR-FTIR and HR-TEM techniques. Galvanostatic cycling showed that the first cycle capacity increased from 205.1 mAhg-1 to 259.0 mAhg-1 after coating, owing to the particle size reduction. GITT analysis also revealed and increase in the Li diffusion coefficient during deep charging/discharging. Moreover, the efficacy of the coating was shown through cycle data after 100 cycles, which showed good Coulombic efficiency with a high average of 99.5 %, and a decrease in voltage fade per cycle by 12.9 %. TOF-SIMS analysis was used to confirm the protective mechanism of the Li2SO4 coating layer, and XPS and Raman Spectroscopy were used to confirm the reduction in transition metal dissolution for the coated sample, which was further confirmed through HAADF STEM analysis. Overall, the successfully synthesized S-CF-LLC paves the future for cobalt-free high-performance batteries.
Enhancing Lithium-Ion Battery Performance through Dual Doping in Ni-Rich Cathodes
Authors: Lee Soo-Been , Sun Yang-Kook
Published: December 2024

Doping is crucial for maintaining the long-term stability of Ni-rich layered cathodes in lithium-ion batteries. However, using a single dopant is often insufficient in achieving a stable, high-energy cathode material. In this study, we used a dual doping approach by employing Al3+ and Nb5+ ions to enhance the cycling stability of Li[Ni0.92Co0.04Mn0.04]O2 (NCM92) cathodes. Al3+ doping reinforces the crystal structure, while Nb5+ doping optimizes the morphology of primary particles. This dual doping strategy not only harnesses the advantages of both dopants simultaneously, but also showcases remarkable performance improvements through synergistic effects. The resulting Li[Ni0.905Co0.04Mn0.04Al0.005Nb0.01]O2 (AlNb-NCM92) cathode, developed via dual Al and Nb doping, demonstrates remarkable stability. These findings highlight the importance of a comprehensive doping strategy that considers both crystal structure and microstructure to maximize the long-term stability of high-energy Ni-rich cathode materials.
The Impact of Li2MnO3 Proportion on the Structure and Electrochemical Performance of xLi2MnO3‧(1-x)LiNi1/3Mn1/3Co1/3O2 for Lithium-Ion Batteries
Authors: Tsai Shu-Yi , Fung Kuan-Zong , Lin Wei-Zhi
Published: December 2024

Lithium-rich layered oxides have recently emerged as promising cathode materials for high-energy storage applications.This study focuses on the synthesis of a range of cathode materials using the sol-gel method. These materials are denoted by the molecular formula xLi2MnO3‧(1-x)LiNi1/3Mn1/3Co1/3O2, where x varies from 0 to 1 in increments of 0.3. The main objective is to explore the structure and electrochemical properties of these cathode materials. The presence of a higher Li2MnO3 content was found to stabilize the Li-rich structure and enhance the overall capacity of the electrodes. This stabilization was attributed to the presence of stable tetrahedral Li within the structure. However, it is important to note that the irreversible reaction of Li2MnO3 had a negative effect on the electrode's capacity, resulting in a reduction in overall capacity.The 0.5Li2MnO3‧0.5Li(Ni1/3Mn1/3Co1/3)O2 composition exhibited the best electrochemical performance. It demonstrated a discharge capacity of approximately 250 mAh/g and a capacity retention of around 215 mAh/g after 30 cycles.
Investigation of Single-Crystal Process for Ni-Rich Layered Oxides Cathode through Solid State Reaction
Authors: Fung Kuan-Zong , Tsai Shu-Yi , Chen Yu-Hsuan , Chen Yu-Fan
Published: December 2024

Processing of Ni-rich NMC layered oxide cathodes commonly adopt the co-precipitation technique. As a result, very uniform oxide particles in nano-meter range are obtained. However, NMC micro-cracks tend to form in these so-called polycrystals due to volume changes after repeated hundreds of charge/discharge cycles.

In recent years, layered oxides developed by a single-crystal process has received great attention. Ni-rich layered oxides with µm-size grain size tend to give better cycling performance with enhanced structural integrity and less volume change during extended cycling tests. Single-crystal process, in fact, involves heating/calcination of oxide/carbonates/nitrates powder compacts. Accordingly, reactions such as decomposition, chemical reactions, diffusion, oxidation, sintering, grain-growth take place as well. Processing parameters such as temperatures and atmosphere play important roles on the grain growth of Ni- rich layered oxides. Furthermore, the lithiation/oxidation of Ni-containing oxides during single-crystal processing may involve charge compensation resulted from defect reactions. During the different stages of processing, the structural, microstructural and electrical properties of decomposed precursors and resultant layered oxides will be examined using XRD, SEM and DC/AC impedance measurements. CV and charge/discharge tests from assembled coin cells will be used to evaluate electrochemical properties of single-crystal Ni-rich layered oxides.
The Structure and Electrochemical Properties of High-Nickel LiNi1−x−YMnxAlyO2 As Cathode Materials for Lithium-Ion Secondary Batteries
Authors: Jung Da-Hee , Shim Jae-Hyun , Choi Woo-Seong , Kim Ju-Whan
Published: December 2024

Recently, due to the expansion of the electric vehicle market, there has been an increasing demand for cathode materials, which are essential components of batteries. Commercialized high-energy density lithium-ion batteries primarily use cathode materials such as high-nickel NCM and NCA. However, the cost of cathode materials is increasing due to limited reserves and supply issues of cobalt, the main raw material for NCM and NCA. Therefore, cobalt-free cathode materials are considered an effective solution to the high cobalt price problem and are seen as a means to lower the cost of lithium-ion secondary batteries.

In high-nickel cathode materials, cobalt suppresses Ni/Li mixing, improving the crystallographic structural stability, and enhances lithium ion conductivity, thereby improving the power characteristics. Consequently, materials with different dopants instead of cobalt are being researched for high-nickel cathodes. A prominent example is NMA, which uses aluminum instead of cobalt.

Despite the cost-saving advantages, NMA has several limitations. Compared to cathodes containing cobalt, NMA exhibits drawbacks such as crystallographic structural instability and the formation of lithium dendrites during charging and discharging, leading to degradation in battery lifespan and stability. Various research efforts are underway to address these issues.

This study aims to analyze the structure of NMA manufactured through various process variables and observe the electrochemical changes of NMA according to its crystal structure. This research involves the analysis of crystal structure using X-ray diffraction (XRD) and scanning transmission electron microscopy (STEM), as well as the analysis of electrochemical properties using electrochemical impedance (EIS) spectroscopy techniques.
Effect of the Mxene Introduced to Hollow-Core Shell Binder on Silicon Anode in Lithium Ion Battery
Authors: Seo Yuri , KIM In Seo , Hwang Chan Hee , Lee Jang Hee , Shin Ye Eun , OH Eun-Suok
Published: December 2024

Mxene-based materials have attracted an attention in the application of next generation lithium ion battries (LIBs) because of their large surface area, excellent conductivity, and well dispertion into water. Our pervious studies on water-dispersible Mxene-containing binder has achieved to the improvement on the electrochemical performance of high-capacity Si anode. In this study, we present a more efficient MXene-containing binder, Mxene-containing acrylic acid-based core-shell structure (MX-ACS) synthesized by in-situ emulsion polymerization. Futhermore, the introduction of MXene segment in MX-ACS improves the conductivity and stability of binder, leading to the extended lifespan and enhanced performance of the batteries.

The effect of Mxene percentage in MX-ACS binder is thoroughly evaluated using various the physical and electrochemical characteristic techniques such as SEM, DSC, TGA, Raman, cyclic performance, EIS, and so on

Keywords: high capacity Si anode, Polymer binder, MXene, acrylic acid-based core-shell

Figure 1
Unravelling the Relationship between Crystallographic Structure and Oxygen Evolution Reaction Activity of Nickel Cobalt Oxide Thin Films
Authors: van Limpt Renee , Lao Mengmeng , Tsampas Michail N. , Creatore Mariadriana
Published: December 2024

The development of a sustainable energy system relies on the production of green hydrogen. One of the major challenges for water splitting is the synthesis of platinum group metal-free oxygen evolution reaction (OER) electrocatalysts. Spinel nickel cobalt oxides (NCOs) have attracted particular interest due to their stable electrocatalytic performance. The less researched rock-salt NCOs, however, are also promising due to their ability to convert to the OER-active hydroxide phase1. Further development of NCO electrocatalysts requires fundamental understanding of their crystallographic structure-OER performance relationship. This work addresses ~20 nm atomic layer deposited (ALD) NCO thin film systems with a broad composition range to unravel the above-mentioned relationship.

Our previously developed ALD supercycle process2 based on Ni(MeCp)2, CoCp2 and O2 plasma is employed to generate a full range of chemical compositions, such that the phase transition from Ni-rich rock-salt films to Co-rich films at ~55 at.% Co can be observed. Extensive material characterisation reveals that the phase transition is accompanied by an increase in the +3/+2 ratio of the oxidation state of both Ni and Co. Electrochemical analysis in 1M KOH shows an optimal performance for the 30 at.% Co rock-salt film after 500 CV cycles and a synergistic effect between cobalt and nickel such that NCO films are more OER active than Co3O4 and NiO. The films show a composition-dependent activation during CV cycling, where a decrease in activation is observed for increasing Co at.%. No activation is observed for the spinel films. The activation is driven by bulk transformation to the active (oxy)hydroxide phase and is accompanied by an increase in electrochemical surface area (ECSA) up to a factor 8 for rock-salt films. The overpotential after cycling is corrected for the increase in ECSA using an original method, which reveals that Ni-rich spinel structure films are intrinsically more active3.

The use of model systems in combination with extensive material characterisation and prolonged electrochemical testing allows us to distinguish two classes of NCO catalysts, the instantly active and highly stable Co-rich spinel films and the high surface area Ni-rich rock-salt phase which develops upon extensive activation . Placing these results in perspective, we conclude that application of these catalysts on high surface area 3D electrodes would benefit from the more intrinsically active spinel NCO films, whilst activated rock-salt films would be the preferred choice for thin film electrocatalysis studies. These results also show that rock-salt NCO films (<40 at.% Co) could be a more sustainable alternative to the more commonly used spinel NCO films.

1Gebreslase et al. J. Energy Chem. 2022, 67, 101-137

2van Limpt et al. JVSTA, 2023, 41, 032407

3van Limpt et al. Adv. Energy Mat. under review

Figure 1
Using Operando Mass Spectrometry to Study Room Temperature C-H Bond Activation of Propane on Pt Electrocatalyst in Aqueous Acidic Electrolyte
Authors: Bhadouria Ashutosh , Tackett Brian Michael
Published: December 2024

C-H bond activation is an important step in order to produce industrially relevant products from readily available light alkane feedstock. Thermally, C-H activation has been hypothesized as a rate-limiting step for various reactions, such as alkane-to-alcohol conversion and alkane dehydrogenation. However, high-temperature processes, typically utilized for such endothermic activations, are energy-intensive and ultimately lead to a large carbon footprint. Therefore, there is a need to enable C-H activation at lower temperatures, and an electrochemical pathway, powered by renewable energy, is a promising alternative. An electrocatalyst can utilize potential as a driving force to initialize the reactivity of light alkanes via activating a C-H bond. Electrochemically, Pt has shown activity towards functionalizing alkanes, although producing an undesired byproduct - CO2 - with high faradaic efficiency. Furthermore, little is known about the adsorption mechanism, identity of adsorbate species, and potential conditions suitable for enabling selective oxidation to valuable intermediates.

Our work uses Electrochemical Mass Spectrometry (ECMS) to elucidate the potential dependence of propane activation on a Pt electrocatalyst. Potentiodynamic profiles enable quantification of charge involved in the proposed faradaic pathway while mass spectrum analysis reveals the identity and quantity of gas-phase species produced. We found that the adsorption of a neutral, non-polar alkane – propane – is dependent on the potential applied at the Pt electrocatalyst in aqueous acidic electrolyte. When propane is introduced in the cell at varying adsorption potential holds, we found that the propane-derived adsorbates reached a maximum coverage at an adsorption potential of 0.3 VvsRHE. An oxidative charge transience was observed when propane was introduced to the cell, which is consistent with a dissociative chemisorption mechanism – via a C-H bond activation. Additionally, the identity of propane-derived adsorbate species was determined via a combination of coulometry and mass spectrometry to quantify the extent of dehydrogenation of C3
* adsorbates.

These results show that propane is activated well within the electrochemical stability of water, and propane-derived adsorbate species preserve the three-carbon propane backbone. Therefore, the adsorbate species can be further functionalized by varying the potential at the electrocatalyst, after the initial adsorption, to make valuable oxidative intermediates. Our findings can be directly applied to tune electrocatalysts in order to selectively activate paraffinic C-H bond at room temperature, aqueous conditions, for decarbonized chemical manufacturing.

Figure 1
Electrochemical Aptasensor for Progesterone Detection
Authors: Carroll Emily , Winterholler Elizabeth , Sparks Taylor D , Minteer Shelley D.
Published: December 2024

Electrochemical biosensors have revolutionized point-of-care diagnostics through commercial accessibility while maintaining detection specificity and sensitivity. Medical biosensors are designed to detect biomarkers in bodily fluids (blood, urine, saliva, sweat) and commonly use enzymes, antibodies, or nucleic acids to bind biomarker targets. An emerging method of biomarker detection uses aptamers which are short, single-stranded DNA or RNA molecules that bind to specific target molecules with high affinity and selectivity. Aptamer sensors are an affordable alternative to antibody-based sensors, have a wider target scope compared to antibody- or enzyme-based assays, and inherently have high structure flexibility and design for redox robe modification. In particular, electrochemical aptamer biosensors (E-AB) represent a promising device architecture wherein an aptamer sequence with a redox probe is tethered to an alkane thiol self-assembled monolayer on a gold electrode (Au-SAM). Upon substrate binding, the conformational changes in the aptamer then enable fast electron transfer to the redox probe and allow rapid and continuous signal transduction of analyte concentrations. E-ABs have been used to target various biomarkers (cocaine, thrombin, tobramycin, vancomycin, etc.) and operate well in vivo, making them an attractive technology for point-of-care diagnostics.

In this work, an E-AB is designed for progesterone monitoring. Progesterone is a key biomarker for monitoring reproductive health, as irregular levels are predictive of unsuccessful pregnancy, abnormal uterine bleeding, early embryonic mortality, or ectopic pregnancy. However, there are no continuous, non-invasive methods for progesterone detection. Current methods are limited to laboratory blood samples, ovulation prediction kits, and cycle tracking, but these methods fall short of achieving continuous, accurate, reliable, non-invasive, accessible, and comprehensive detection. Here, we develop an E-AB with a specific affinity for progesterone using the established Au-SAM architecture, a methylene blue redox reporter, and an aptamer sequence with a high affinity for progesterone. These experiments show proof of concept that an immobilized aptamer with methylene blue can detect progesterone electrochemically and is a promising platform for continuous monitoring of progesterone in vivo.
Elucidating the Mechanism of Nickel-Mediated Electrochemical Alcohol Oxidation Using in-Situ X-Ray Absorption Spectroscopy and Microkinetic Modeling
Authors: Siboonruang Tana , Hannagan Ryan Travis , Schröder Johanna , Jaramillo Thomas F. , Hoffman Adam S. , Tang Maureen , Burke Stevens Michaela
Published: December 2024

Electrochemical alcohol oxidation (AOR) is an attractive replacement for oxygen evolution reaction (OER) in hydrogen production. Compared to OER, AOR has a lower thermodynamic potential and produces higher value products. Nickel-mediated AOR has been proposed to proceed through a chemical, redox pathway preferred by aldehydes (geminal diols in alkaline electrolyte), and a potential dependent pathway preferred by alcohols. The precise mechanism of these reactions and their effects on the material are not well understood. Using furfural and furfuryl alcohol as model molecules, we elucidate the mechanism of nickel-mediated AOR. In-situ tracking of the Ni K edge using x-ray absorption spectroscopy (XAS) reveals nickel is at a more reduced state during AOR compared to when no organic reactant is present. The nickel oxidation state profile, however, varies depending on the reactant present (furfural vs. furfuryl alcohol). Product analysis shows that competition for catalytic sites with OER at high potential could contribute to these differences. Microkinetic modeling explores the potential dependence of the Ni K edge position by studying the interplay between the rate of electrochemical nickel oxidation and its chemical reduction through reaction with alcohol. Understanding this relationship will identify rate-limiting steps and active (and inactive) phases for AOR. Insights from this model system will motivate novel guidelines for AOR catalyst design.
Exploring the True Nature of Doping Effects: The Origin of the Discrepancy in Doping Effects on Ni-Rich Cathode Materials
Authors: Kwon Doo Seok , Bang Jin Ho
Published: December 2024

Co-free, Ni-rich batteries have gained significant traction due to their importance and popularity in the field. Despite numerous doping studies aimed at mitigating the drawbacks associated with Co-free batteries, the outcomes have been inconsistent. This research endeavors to elucidate the true essence of doping effects by employing dopants (Nb, Ti, Zr, Hf, Ta, W, Mo) commonly utilized in Li(Ni0.95Mn0.05)O2 cathode. The findings reveal the advantageous impact of various dopants on doping, albeit to varying extents contingent upon temperature. Notably, each dopant exhibits distinct effects on both the promotion and inhibition of grain size, contingent upon temperature variations. These findings underscore the significance of optimizing temperature conditions to maximize the doping effect, aligning with the unique characteristics of each dopant. Consequently, comprehending temperature modulation in accordance with the growth and suppression traits of individual dopants holds paramount importance for the advancement of high-performance Co-free, Ni-rich cathode.
Differentiating the Aging Mechanisms of Si Anodes
Authors: Chen Zonghai , Cai Jiyu
Published: December 2024

Si-based materials have been widely considered promising high capacity anode materials for high energy density lithium-ion batteries. However, the large scale adoption of Si-based anodes is hindered by their rapid performance degradation during cycling and aging. Understanding the fundamental of failure mechanisms is crucial for rational technology development, aiming at extending the cycle life and calendar life of lithium-ion batteries using Si-based anodes. in this work, both OCV aging and high precision leakage current measurement were utilized to characterize the kinetic of parasitic reactions on Si anodes with the presence of various electrolytes. Particularly, the concept of charge balance is adopted to quantitatively describe the electrochemical impact of charge consumption during aging. It was found that the composition of electrolytes pose significant impact on the electrochemical and mechanical stability of solid/electrolyte interphases. Finally, the implication and application of charge balancing for battery development will also be discussed.
Unraveling Lithium Plating and SEI Properties during Fast Charging of Li-Ion Batteries
Authors: Luo Mei , Gao Xiang , Mijailovic Aleksandar S , Wang Guanyi , Jansen Andrew N. , Yang Zhenzhen , Wu Qingliu , Sheldon Brian W. , Xu Jun , Lu Wenquan
Published: December 2024

As the electric vehicles market expands rapidly, the need for fast-charging lithium-ion batteries become increasingly imperative. However, the persistence of lithium plating, particularly on graphite negative electrodes in state-of-the-art lithium-ion batteries (LIBs), continues to pose performance degradation and safety hazards. Understanding the dominant limitation mechanism remains a subject of controversy. To evaluate the dominant role among particle-level diffusion and charge-transfer at the electrode interphase, we utilized ultra-thin electrodes with different-size graphite particles in conjunction with a pseudo-2-dimensional (P2D) model to evaluate the most likely plating mechanism. The superior performance of small graphite particles, coupled with well-matched modeling data, indicated that particle-level diffusion is the primary mechanism contributing to plating at high rates. Furthermore, we investigated how fast-charging rates influence the morphology of lithium dendrites and their solid electrolyte interphase (SEI) properties using 1.6 Ah pouch cells featuring a LiNi0.5Mn0.3Co0.2O2 cathode and graphite anode provided by Nanoramic Laboratories. Our investigation involved a comparative analysis of the aging behavior of NMC/Gr cells subjected to various charging rates — 0.5C, 2C, 4C, and 6C. Through a series of post-mortem characterizations, including electrochemical impedance spectroscopy (EIS), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS), we identified distinct dendrite morphologies at the graphite anode under varying charging rates, along with fluorine-richer SEI for faster charging process. These findings provide a comprehensive understanding of lithium plating mechanisms, offering valuable insights into the fast-charging behavior in practical Li-ion battery applications.

Acknowledgement

This material is based upon work supported by the U. S. Department of Energy’s Office of Energy Efficiency and Renewable Energy (EERE) under the Advanced Manufacturing Office, award number DE-EE0009111. This work was mainly conducted at the Cell Analysis, Modeling, and Prototyping Facility at Argonne National Laboratory. We used resources of the Center for Nanoscale Materials, U.S. Department of Energy (DOE) Office of Science User Facilities operated for the DOE Office of Science by Argonne National Laboratory under Contract DE-AC02-06CH11357.
LIOVIX® Printable Lithium Technology for Roll-to-Roll Lithium Anode Manufacturing
Authors: Xia Jian , Fitch Brian , Yakovleva Marina
Published: December 2024

Arcadium Lithium Corporation has developed LIOVIX®printable lithium technology; a formulation which combines Stabilized Lithium Metal Powder (SLMP®) and rheology modifiers in a stable suspension that can be printed on most common substrates where a controlled amount of lithium metal is needed. For example, LIOVIX® can be printed on the surface of a pre-fabricated electrode. We have successfully demonstrated this technology in pre-lithiating SiO/Graphite anodes in the range of 0% to 100% of SiO content. LIOVIX® can also be printed as a thin lithium layer on the current collectors, separators, and even solid electrolytes to be used for lithium metal anode applications. The advantage of this technology is that the thickness of the printed lithium layer can be easily controlled. We have demonstrated printed lithium layer thickness in the range of 5µm to 50µm on a variety of substrates. LIOVIX® printable lithium technology is easily scalable using standard battery industry coating and printing equipment. We will present recent progress using R2R pilot equipment development as well as performance data in large format cells that have our technology incorporated.

Figure 1. Pilot scale R2R coater demonstration for production of the 20 µm lithium foil

Figure 1
Understanding Degradation Modes in High-Temperature 18650 Cylindrical Cells to Project Low-Temperature Lifetimes
Authors: Floras Claire , Tuul Kenneth , Martin Maher Sasha , Metzger Michael , Dahn Jeff R.
Published: December 2024

With advances in Li-ion batteries allowing for decades of cycling, there is an incentive to produce accurate lifetime predictions without waiting for the cell to reach end of life1. Since failure mechanisms become apparent more rapidly when cycling at elevated temperatures2, comparing the performance of cells cycling up to 100 °C to ambient temperature cells of the same chemistry and electrolyte composition is useful. Single crystal NMC/artificial graphite chemistries of 60% Ni and low Co concentrations were combined with varying electrolytes which are operable over a wide temperature range without exhibiting significant gassing and while maintaining good capacity retention3.

By reducing and eliminating degradation modes, such as electrolyte permeation through the cell seal at high temperature, impedance growth, salt consumption, and gas generation, an experiment can be designed wherein the primary degradation mode is Li inventory loss. Once this is the case, and using ultra-high precision coulometry (UHPC) to collect data like that shown in Figure 1, lifetime predictions can be made and validated in combination with long-term CCCV results. Post-mortem analyses of cells can also provide insight into these degradation mechanisms and their implications for lifetime predictions.

Figure 1. fractional capacity vs cycle for NMC 640 pouch cells (black diamonds) and varying 18650 cylindrical cells (NMC640 red circles, NMC60:35:5 blue squares, NMC631 green triangles). The pouch cells and the 18650 cylindrical cells were cycled at C/20 from 3.0-4.0 V on a UHPC instrument. The negative electrode was artificial graphite.

References

[1] C. P. Aiken et al., J. Electrochem. Soc., 169, 050512 (2022).

[2] T. Taskovic, A. Eldesoky, W. Song, M. Bauer, and J. R. Dahn, J. Electrochem. Soc., 169, 040538 (2022).

[3] K. Tuul, S. Martin Maher, C. Floras, W. Black, T. Taskovic, S. Chisholm, A. Clarke, E. Lust, and J. R. Dahn, J. Electrochem. Soc., Under review (2024)

Figure 1
Understanding Capacity Recovery Behavior Using Long-Term Stored Pouch Cells
Authors: Park Siyoung , Lee Yong Min , Lee Hyobin , Jung Tai-Jong , Lim Jaejin , Kang Dongyoon , Song Jihun , Doh Chil-Hoon , Eom Seungwook , Yu Ji-Hyun , Ha Yoon-Cheol
Published: December 2024

Commercial lithium-ion batteries often experience capacity and power degradation when stored for extended periods after production. Interestingly, the reduced capacity can be partially recovered over time when the cells are cycled again, a phenomenon known as capacity recovery. However, it is difficult to separate the analysis of capacity recovery from the capacity decay during recycling. Additionally, the widely accepted explanation for capacity recovery, the passive anode effect (PAE), focuses solely on the lithium inventory within the overhang anode site. To address these challenges, we studied large-capacity LiNi0.4Co0.3Mn0.3O2/graphite pouch cells that were stored for 4 years. During recycling, the capacity gradually recovered over 120 cycles, and this fully recovered capacity was maintained for up to 500 cycles, indicating minimal additional capacity decay during recycling. Our investigation also highlighted the significant impact of breakdown and thinning of the calendar-aged solid electrolyte interphase (SEI) on the entire anode site, affecting both capacity and power recovery beyond just the PAE. Furthermore, by integrating both the PAE and breakdown of the calendar-aged SEI into a life prediction model, we were able to predict the capacity recovery behavior for up to 1000 cycles under various operating conditions. This comprehensive approach provides insights into understanding and predicting the long-term performance of lithium-ion batteries, particularly in relation to storage-induced capacity degradation and subsequent recovery during cycling.
Three-Layer Electrorefining of Molten Zinc Held on Porous Carbon or Silica Sheets in Molten LiCl–KCl–ZnCl2
Authors: Yasuda Kouji , Yamada Shoya , Uda Tetsuya
Published: December 2024

A three-layer electrolysis process utilizing porous holding materials with the impermeability to liquid metals due to the poor wettability but permeability to molten salt electrolytes was investigated, which enables to establish a three-layer configuration of metal(l)/electrolyte(l)/metal(l) by holding metals above the electrolyte regardless of their densities. Porous carbon or silica sheets were selected as the holding materials of liquid Zn, and upper electrode to hold liquid Zn was prepared. Electrorefining experiments was carried out in molten LiCl–KCl–ZnCl2 at 723 K. Three types of experiments were carried out focusing on anodic polarization, electrorefining with cathodic carbon, and three-layer electrolysis using liquid Zn as cathode.

Anodic polarization experiments clarified that evolution of a large amount of Cl2 gas was observed from the graphite components of the upper electrode when a more positive potential than the Cl2/Cl− was applied. The use of insulating silica fiber sheets and holding material allowed for dissolution of Zn at higher current density without gas evolution. In the electrorefining experiments, synthesized crude zinc and ISP crude zinc were electrolyzed to obtain purified Zn at the cathode. The concentration of impurity elements in the cathode Zn was reduced by a factor of 8 to 200 compared to the value in the crude zinc, highlighting the purification effectiveness of the method. In the Zn(l)/electrolyte(l)/Zn(l) three-layer electrolysis, it was verified that the upper electrode was applicable as either an anode or cathode. Current efficiencies were close to 100% in all electrorefining and three-layer electrolysis experiments. From the results obtained, challenges associated with the three-layer electrolysis process were identified, and countermeasures to solve them were proposed.

Acknowledgement: This work is conducted as a collaboration research of Laboratory of Design of Sustainable Materials and Processing, and Laboratory of Non-ferrous Extractive Metallurgy, Department of Materials Science and Engineering, Graduate School of Engineering, Kyoto University. Laboratory of Non-ferrous Extractive Metallurgy is an endowed chair by Mitsubishi Material Corp. We would like to acknowledge Prof. Hisaaki Fukushima at Kyushu University, Prof. Takashi Nakamura at Tohoku University, and Dr. Akihiro Kishimoto at Kyoto University for their valuable discussion. We also acknowledge Mitsui Mining & Smelting Co., Ltd., for supplying the prime western grade metal zinc (ISP crude zinc).