bluuebunny/crossref_metadata_2025 huggingface dataset:
(Invited) Mesoscale Design of Semiconductor Photoelectrodes for Energy Conversion
Authors: Lewis Nathan S
Published: December 2024

We are developing materials to enable the direct capture of sunlight and electrochemical production of chemical fuels such as hydrogen, inspired by the Fujishima-Honda effect. To extend the response into the visible region of the solar spectrum, we are designing photoelectrodes consisting of 3D, mesostructured semiconductor components decorated with heterogeneous catalysts to drive fuel-forming electrochemical reactions at low overpotentials. High aspect-ratio semiconductor rods enable the use of low cost, earth-abundant semiconductor photoelectrodes without sacrificing energy conversion efficiency, due to orthogonalization of light absorption and charge-carrier collection. Inorganic phototropic growth due to light-directed electrodeposition of p-type semiconductors yields tunable anisotropic wetting of surfaces in accord with the Lotus leaf effect, also as pioneered by Prof. Fujishima. A series of phosphide and antimonate materials provides alternatives to traditional catalysts based on platinum-group for catalysis of the hydrogen-evolution and oxygen-evolution reactions. Additionally, thick, uniform TiO2 coatings similar to those used by Fujishima for self-cleaning coatings can chemically protect semiconductor photoelectrodes without compromising light collection or electrical conduction.
Inorganic Photocatalysts for Accelerating Water Dissociation in Bipolar Membrane Interfaces
Authors: Lenef Julia D. , Deutsch Todd G
Published: December 2024

Bipolar membranes (BPMs) are important functional materials for the advancement of next-generation water electrolyzers, CO2 electrolyzers, and electrodialysis for direct ocean capture (DOC) of CO2. BPMs consist of both an anion exchange membrane and cation exchange membrane that can maintain large pH gradients across the junction, enabling independent optimization of the catalyst and electrolyte to achieve favorable kinetics and thermodynamics. However, many of these applications are limited by energy efficiencies from slow water dissociation (WD) kinetics of the dissociation catalyst at the interface of the BPM, which generate OH- and H+ from H2O in a reverse biased BPM. To address this, we harness visible-light active photocatalyst particles to assist in the dissociation reaction, therefore, minimizing the overpotential and resulting cell voltages. The visible-light active photocatalyst—Pt-doped TiO2—were selected due to its desirable pH stability and absorbance in the visible region compared with undoped TiO2. Using electrochemical methods in a water electrolysis cell, we observe a reduction in the membrane impedance by electrochemical impedance spectroscopy (EIS) and a reduction in the overall cell voltage by cell polarization (i.e., V-I) measurements. Robust materials characterization by X-ray fluorescence (XRF), inductively-coupled plasma mass spectrometry (ICP-MS) and cross-sectional scanning electron microscopy (SEM)/energy dispersive spectroscopy (EDS) reveal the effect of increasing catalyst loading on the membrane resistances during operation. By controlling the WD photocatalyst loading, we provide (1) the first detailed study on its effect on the electrolysis cell performance and (2) a thorough quantification and microscopic visualization of the embedded catalyst particles in the polymer matrix. This research provides a light-activated pathway to increasing the device energy efficiencies coupled with a comprehensive understanding of the true loading (i.e., in contrast to indirect methods) and catalyst distribution across the interface.
One-Pot Solution Synthesis of Bulk and Surface Simultaneously Optimized BiVO4 Photoanode with Enhanced Photoelectrochemical Water-Splitting Activity
Authors: Hwang Sung Won , Jeong Yoo Jae , Cho In Sun
Published: December 2024

Bismuth vanadate (BiVO4, BVO) with a monoclinic crystal structure has attracted significant interest in photoelectrochemical (PEC) and photocatalytic (PC) oxidation that are utmost critical processes to producing clean hydrogen fuels from solar energy. BVO has a suitable bandgap (2.4 eV), which enables it to absorb sunlight up to a wavelength of 520 nm. Furthermore, it possesses a suitable location of the valence band edge for water oxidation, decent photoelectrochemical/photochemical activity, and moderate stability in neutral electrolytes. Nevertheless, PEC performance is hindered by diverse inherent drawbacks, including inadequate conductivity and mobility, limited light absorption, and significant charge recombination at the bulk and surface 1,2.

This study demonstrates a novel one-pot solution method to synthesize high-performance BVO photoanodes for photoelectrochemical (PEC) water-splitting. We designed a stepwise dual reaction (SDR) to optimize the bulk and surface characteristics via texturing and surface reconstruction. The key innovation lies in controlling precursor concentration, ethylene glycol (EG), and manipulating growth kinetics and surface reconstruction. EG plays a crucial role in achieving this texture and surface reconstruction. Compared to conventional BVO (non-textured and non-surface-reconstructed), the optimally synthesized textured and surface-reconstructed BVO (ts-BVO) exhibits significantly improved charge transport (70% vs. 8%) and surface charge transfer efficiencies (85% vs. 9%). Furthermore, by depositing the CoBi oxygen evolution electrocatalysts, the ts-BVO achieved a steady photocurrent density of 4.3 mA/cm2 at 1.23 V vs. the reversible hydrogen electrode (RHE) and an almost unity Faradaic efficiency of 98% under simulated sunlight illumination (1 sun). Our findings highlight the effectiveness of solution chemistry in controlling the texture and surface characteristics of photoanode for efficient photoelectrochemical water-splitting 3,4.

Keywords: One-pot hydrothermal, ethylene glycol, BiVO4, texture, surface activation, photoelectrochemical water-splitting

Reference

1 H. S. Han, S. Shin, D. H. Kim, I. J. Park, J. S. Kim, P. S. Huang, J. K. Lee, I. S. Cho and X. Zheng, Energy Environ Sci, 2018, 11, 1299–1306.

2 Y. J. Jeong, S. W. Hwang, S. Chaikasetsin, H. S. Han and I. S. Cho, Chemical Engineering Journal, 2022, 435, 135183.

3 I. S. Cho, H. S. Han, M. Logar, J. Park and X. Zheng, Adv Energy Mater, 2016, 6, 1–9.

4 I. S. Cho, Z. Chen, A. J. Forman, D. R. Kim, P. M. Rao, T. F. Jaramillo and X. Zheng, Nano Lett, 2011, 11, 4978–4984.
(Invited) Combining Biocatalysis with Electrochemistry for Organic Electrosynthesis
Authors: Minteer Shelley D.
Published: December 2024

As the world is considering electrification of everything from cars to industry, there has been a recent push for the electrification of the chemical industry, but the challenge is that electrochemistry rarely has the selectivity needed for the production of pharmaceutical chemicals. This paper will discuss the combination of enzymatic biocatalysis with electrochemistry to improve the selectivity of organic chemical electrosynthesis. This paper will include a discussion of the major challenges in the field, including: cofactor regeneration, facile electron transport, solubility, and stability.
Dissolution of Spent NCM Cathodes Via Electron Transfer from the Anaerobic Respiration of Shewanella Putrefaciens
Authors: Kim Seongryeong , Jung Haesung
Published: December 2024

With the rapid growth of the electric vehicle (EV) market, the global demand for lithium-ion batteries (LIBs) is increasing significantly. As the LIB market expands, we are also confronting the challenge of disposing of the increasing number of spent LIBs. Currently, pyrometallurgy and hydrometallurgy are the commercialized methods for recycling spent LIBs. However, these processes result in significant environmental pollution, high energy consumption and the depletion of valuable resources such as Li and Mn in the slag. Here, we explored the dissolution of spent NCM622 cathodes, a critical component of LIBs, using bioleaching via the anaerobic respiration of Shewanella putrefaciens bacteria in the neutral environment (i.e., pH 7.5). This study enhances the novelty of bioleaching as an eco-friendly and simple technology. The spent NCM622 cathodes were dissolved by approximately 79 % within four weeks. Using X-ray photoelectron spectroscopy (XPS), we confirmed the electron transfer from S. putrefaciens to the NCM622 cathode. Before the reaction, the oxidation states of the elements in the NCM622 were identified as Ni (III), Co (III), and Mn (IV). After the reaction, the metals were reduced to Ni (II), Co (II), and Mn (II/III), respectively, by the respiration of S. putrefaciens under anaerobic conditions. When S. putrefaciens respired under anaerobic conditions, electrons were transferred to the metals in the NCM622, and the metals in the NCM622 were reduced and subsequently dissolved (i.e., dissimilatory process). This study provided a new mechanism of bioleaching of valuable metals in spent LIBs under environmentally sustainable conditions through the dissimilatory process by S. putrefaciens. Furthermore, this technology could be expanded to advance microbial fuel cells (MFC), enabling the recycling of spent cathodes in LIBs while generating electricity.
A Sulfurized Carbon Cathode for High-Capacity and Long-Life Lithium–Sulfur Batteries
Authors: Luo Mei , Calvary Caleb Aaron , Qin Yan , Jansen Andrew N. , Hood Zachary D. , Liu Yuzi , Villegas Salvatierra Rodrigo , Lu Wenquan
Published: December 2024

Lithium–sulfur (Li–S) batteries have emerged as promising candidates for next-generation energy storage systems due to their high energy density and low cost. However, challenges such as the low conductivity of sulfur, the notorious "shuttle effect," and substantial volume expansion during charge/discharge cycles have hindered their practical applications. In this study, we introduce sulfurized carbon (SC), a variant of sulfurized poly(acrylonitrile), developed by Zeta Energy, as a cathode material for Li–S batteries, which could mitigate the shuttle effect and enable long cycling life. Remarkably, our SC cathode exhibits a high reversible capacity exceeding 660 mAh/g at a C/3 current rate, maintaining stable retention over 1000 cycles. Moreover, it demonstrates commendable rate capability, sustaining over 92% capacity at a discharge rate of 2C, along with a high area capacity exceeding 3.5 mAh/cm², enabling practical high energy density applications. A series of characterizations, such as Scanning Electronic Microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), have been utilized to investigate the exact molecular structure and its electrochemical reaction mechanism. Additionally, we investigate the effectiveness of incorporating single-wall carbon nanotubes (SWCNTs) as an alternative to the conventional carbon black conductive additive for this SC cathode, and discovered an enhanced electronic conductivity, a significant reduction in charge-transfer resistance and a notable increase in cell capacity. Overall, this work provides insights into sulfur cathodes, paving the way to advance lithium–sulfur battery technology for electric vehicle applications.

Acknowledgements

The information, data, or work presented herein was funded in part by the Advanced Research Projects Agency – Energy (ARPA-E), U.S. Department of Energy. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. 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.
Manipulating the Electronic Structure of Polar Eelectrocatalysts for Rapid Sulfur Redox Kinetics
Authors: Xu Huifang , Jiang Qingbin , Hui Kwan San , Hui Kwun Nam
Published: December 2024

Heterogeneous structures and doping strategies have been intensively used to manipulate the catalytic conversion of polysulfides to enhance reaction kinetics and suppress the shuttle effect in lithium-sulfur (Li-S) batteries. However, understanding how to select suitable strategies for engineering the electronic structure of polar catalysts is lacking. Here, we conducted a comparative investigation between heterogeneous structures and doping strategies to assess their impact on the modulation of the electronic structures and their effectiveness in catalyzing the conversion of polysulfides. Our findings reveal that Co0.125Zn0.875Se, with metal-cation dopants, exhibits superior performance compared to CoSe2/ZnSe heterogeneous structures. The incorporation of low Co2+ dopants induce the subtle lattice strain in Co0.125Zn0.875Se, resulting in the increased exposure of active sites. As a result, Co0.125Zn0.875Se demonstrates enhanced electron accumulation on surface Se sites, improved charge carrier mobility, and optimized both p-band and d-band center. The Li-S cells employing Co0.125Zn0.875Se catalyst demonstrate significantly improved capacity (1261.3 mAh g−1 at 0.5 C) and cycle stability (0.048% capacity delay rate within 1000 cycles at 2 C). This study provides valuable guidance for the modulation of the electronic structure of typical polar catalysts, serving as a design directive to tailor the catalytic activity of advanced Li-S catalysts.
(Invited) Quantifying Li Plating on Graphite during Fast Charging of Li-Ion Batteries
Authors: McCloskey Bryan D.
Published: December 2024

Li-ion battery fast charge is limited due to challenges posed by lithium plating on the graphite anode, whereby the large overvoltage necessary to drive high Li+ insertion rates instead results in favorable thermodynamic conditions for Li metal deposition on the graphite surface. Li plating is difficult to detect, particularly in small quantities, and results in safety risks and capacity fade due to lithium metal’s high reactivity with conventional electrolytes. Here, we present our efforts to develop both chemical and electrochemical methods to precisely quantify Li plating and detect the state-of-charge (SOC) onset of lithium plating on graphite electrodes during constant current fast charging. We will discuss titration mass spectrometry (TiMS), a highly sensitive (~20 nmol resolution, or 0.5 µAh of plated Li) chemical analysis where gases evolved from harvested graphite electrodes immersed in acid are used to quantify various solid electrolyte interphase species, including electrically isolated (inactive) Li metal.1 TiMS is then used to determine the precise onset of Li plating and to distinguish between the various capacity fade mechanisms that arise during fast charge.2 We then will discuss the use of simple electrochemical cycling techniques to quantify irreversible Li plating in Li|Graphite half-cells as a function of energy density (electrode thickness), charge rate, temperature, and SOC.3 Similar methods are developed to quantify in-situ Li plating for commercially relevant Graphite|LiNi0.5Mn0.3Co0.2O2 (NMC) cells. In combination, all of these techniques provide a highly accurate measure of the onset of Li plating and quantitative insight into capacity losses during fast charging.

1. McShane, E. J.; Colclasure, A. M.; Brown, D. E.; Konz, Z. M.; Smith, K.; McCloskey, B. D., Quantification of inactive lithium and solid–electrolyte interphase species on graphite electrodes after fast charging. ACS Energy Lett. 2020, 5 (6), 2045-2051.

2. McShane, E. J.; Bergstrom, H. K.; Weddle, P. J.; Brown, D. E.; Colclasure, A. M.; McCloskey, B. D., Quantifying graphite solid-electrolyte interphase chemistry and its impact on fast charging. ACS Energy Lett. 2022, 7 (8), 2734-2744.

3. Konz, Z. M.; Wirtz, B. M.; Verma, A.; Huang, T.-Y.; Bergstrom, H. K.; Crafton, M. J.; Brown, D. E.; McShane, E. J.; Colclasure, A. M.; McCloskey, B. D., High-throughput Li plating quantification for fast-charging battery design. Nature Energy 2023, 8 (5), 450-461.
Reassessing the Quantity of Lithium in Metal Batteries: The Less Is More Philosophy from Metal-Free to Metal Anode
Authors: Wang Di , Qiu Jie , Inui Naoki , Hagiwara Rika , Hwang Jinkwang , Matsumoto Kazuhiko
Published: December 2024

Lithium metal-free batteries (LMFBs, often called anode-free batteries), characterized by the absence of pre-loaded lithium metal or host materials at the anode, have emerged as a focal point in battery research due to their theoretically highest energy density.[1] However, LMFBs face significant challenges: their practical energy density and cycle performance are severely limited by lithium inventory loss during initial charging and the limited reversibility of lithium plating/stripping during battery cycles.[2] We reassess the impact of lithium metal quantity at the anode on battery performance.[3] By incorporating a minimal amount of lithium, lean lithium metal batteries (LLMBs) slightly compromise energy density (the 'less') but, as demonstrated in Figure 1, achieve higher practical energy densities and longer lifespans than LMFBs (the 'more') with an N/P ratio of 0.2, an average lithium Coulombic efficiency of 99.9%, and considering an initial capacity loss of 5%. This makes LLMBs a pragmatic choice even under lenient technical conditions.

It is important to note that this discussion does not endorse one over the other; LMFBs and LLMBs inherently share many similarities and overlapping technologies, such as benefits derived from advanced electrolytes and protocol management. Moreover, LMFBs offer manufacturing advantages by avoiding strict measures required for handling fragile lithium metal, presenting distinct benefits. Additionally, performance metrics derived from LLMBs are invaluable for guiding future LMFB evaluations. Certain LMFB enhancements, like the creation of artificial SEI layers or the use of 3D current collectors, might inadvertently increase battery weight and size, negating the foundational purpose of LMFBs. In such scenarios, the energy density and battery performance of LLMBs, under comparable conditions, can serve as benchmarks to assess the tangible impact of such interventions on LMFBs, ultimately aiming to genuinely elevate battery efficacy.

References

[1] S. Nanda, A. Gupta, A. Manthiram, Adv. Energy Mater. 11 (2021) 2000804.

[2] C. Heubner, S. Maletti, H. Auer, J. Hüttl, K. Voigt, O. Lohrberg, K. Nikolowski, M. Partsch, A. Michaelis, Adv. Funct. Mater. 31 (2021) 2106608.

[3] D. Wang, J. Qiu, N. Inui, R. Hagiwara, J. Hwang, K. Matsumoto, ACS Energy Lett. 8 (2023) 5248.
Revealing the Molecular Origin of Driving Forces and Thermodynamic Barriers for Li+ Ion Transport to Electrode-Electrolyte Interfaces
Authors: Aggarwal Abhishek , Gordiz Kiarash , Baskin Artem , Grossman Jeffrey , Shao-Horn Yang
Published: December 2024

Researchers around the world are working to increase the energy-efficiency and the energy density of lithium-ion batteries. However, the mechanism and the factors influencing the charge transfer (CT) kinetics at the electrode-electrolyte interface remain poorly understood. In this work, we provide atomistic understanding of the interfacial CT mechanism, the underlying microscopic steps, and CT rates at an electrode-electrolyte interface. In addition, we connect our computational results with the experimental measurements and Marcus-like theories of charge transfer. Using state-of-the-art computational techniques, such as metadynamics and molecular dynamics simulations, we model the electrode (cathode)-electrolyte interface and compute the free energy profiles of Li-ion adsorption at the interface, subsequent ion-desolvation and intercalation into the cathode. We study the adsorption of Li+ ion on Li0.5CoO2 (104) surface for different electrolytes, and salt compositions to uncover the trends governing charge transfer kinetics. Using the free energy profiles of Li+ desolvation and intercalation at the solid-liquid interface, we provide estimation of the adsorption and desolvation energy at the interface and find out the key thermodynamic barrier(s) which act as a roadblock for ion transfer in Li-ion batteries. We then study the influence of various components of the battery and propose ways to tune the energy barrier for ion transport. We find that increasing the salt concentration in the electrolyte increases the accessible solvation states to Li+ ion, thereby changing the energy barrier for the Li+ ion to intercalate into the electrode. Moreover, we find that changing the salt from LiPF6 to LiClO4 further modifies the energy landscape of Li+ ion and can enhance the performance of the battery. This work builds an understanding of the effect of salt concentration and electrolyte composition on the Li+ transport properties at interfacial regions. Our computational framework can provide descriptors to enhance the performance and stability of lithium-ion batteries.
Importance of Fluorine in Non-Flammable High Voltage Electrolytes for LNMO||SiGr Cell Chemistry
Authors: Leopold Maike , Woelke Christian , Winter Martin , Cekic-Laskovic Isidora
Published: December 2024

Due to their high energy density and long cycle life, lithium-ion batteries are becoming increasingly important in energy storage and electric vehicle applications. On the cathode side, the high voltage LiNi0.5Mn1.5O4 (LNMO) electrode has emerged as a promising candidate enabling a high reversible specific capacity of 147 mAh g-1 and high theoretical energy density of 650 Wh kg-1. The complete elimination of Co as a critical raw material is also important with regards to the fluctuating costs and environmental impact.1 Combined with silicon-based electrodes and the roughly ten-fold increase in specific capacity of Si compared to the state-of-the-art graphite, achievable energy density of the resulting cell chemistry can be significantly improved.2

In this work a flame retarded high voltage electrolyte formulation for 250 mAh LNMO||SiGr pouch cells, was designed and comprehensively characterised. Next to the electrochemically stability up to 5 V vs. Li|Li+, suppression of Mn and Ni dissolution and the ability of enabling formation of effective SEI and CEI layers are standing out as the electrolytes key features. By using fluorinated solvents and co-solvents in comparison to non-fluorinated solvents, a high voltage oxidative stability up to 5.0 V vs. Li|Li+ and effective interphases (SEI and CEI) formation could be achieved. Likewise, the galvanostatic cycling performance and the accumulated discharge energy was increased by approximately 62 %, while the roll over failure was suppressed for more than 500 charge/discharge cycles. The addition of a flame-retardant additive in amount of only 1 wt.% to the fluorinated solvents mixture resulted in a non-flammable electrolyte with sufficiently good cycle life.

References:

[1] T. Fu, D. Lu, Z. Yao, Y. Li, C. Luo, T. Yang, S. Liu, Y. Chen, Q. Guo, C. Zheng, W. Sun, J. Mater. Chem.,
11, 13889-13915 (2023). DOI: 10.1039/D3TA01777J

[2] C. Wölke, B. Sadeghi, G. Eshetu, E. Figgemeier, M. Winter, I. Cekic-Laskovic, Adv. Mater. Interfaces,

9
, 2101898 (2022). DOI:10.1002/admi.202101898
Impact of Graphite Materials on the Consumption of Prop-1-Ene-1,3-Sultone and Vinylene Carbonate in Lithium-Ion Cells
Authors: Adamson Anu , Tuul Kenneth , Metzger Michael
Published: December 2024

It has been shown that electrolyte additives can be highly beneficial to the performance and lifetime of lithium-ion cells.1,2 However, many additives are consumed in the early cycles, which will affect the cycling performance of the cell over long-term operation. It has been shown that most electrolyte additives are consumed relatively early. For example, when ≤2 wt% vinylene carbonate is used in Li[Ni0.33Mn0.33Co0.33]O2/graphite cells, most of it is consumed during the first 200 h of cell operation.3

Prop-1-ene-1,3-sultone (PES) and vinylene carbonate (VC) are among the most used electrolyte additives in lithium-ion cells. PES is useful for suppressing gas formation, and VC has been found to form a stable solid-electrolyte interphase (SEI), preventing further electrolyte decomposition on the negative electrode. The SEI formed by the decomposition of both additives on the negative electrode surface has been thoroughly characterized.4 However, the dependence between the consumption of these additives and the choice of negative electrode has not been thoroughly examined.

In this work, the consumption of PES and VC was investigated in Li[Ni0.8Mn0.1Co0.1]O2/artificial graphite (NMC811/AG) or Li[Ni0.83Mn0.06Co0.11]O2/artificial graphite (Ni83/AG) pouch cells with four different artificial graphites. The physical properties of these graphite materials were reported by Eldesoky et al.5 Various amounts of VC and PES (alone or in combination with each other) between weight percentages of 0.5 to 2% were used. The cells were formed, after which the electrolytes were extracted and analyzed with quantitative GC-MS to find the amount of additives consumed.

This study demonstrates the significant effect the choice of artificial graphite has on PES and VC consumption rates. In addition, the impact of varying additive amounts and using graphites with different physical properties on formation parameters such as first-cycle efficiency (FCE), charge transfer resistance (Rct), and gas production will be shown.

References

E. R. Logan et al., J. Electrochem. Soc., 167, 130543 (2020).

T. Taskovic, L. M. Thompson, A. Eldesoky, M. D. Lumsden, and J. R. Dahn, J. Electrochem. Soc., 168, 010514 (2021).

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

L. Madec et al., J. Electrochem. Soc., 162, A2635 (2015).

A. Eldesoky et al., J. Electrochem. Soc., 169, 010501 (2022).
(ECS Battery Division Research Award) Sustainable LiFePO4 and LiMn
x
Fe1-X
PO4 (x = 0.1 to 1) Cathode Materials for Lithium-Ion Batteries: From Materials to Systems
Authors: Nekahi Atiyeh , Kumar Anil , Li Xia , Deng Sixu , Zaghib Karim
Published: December 2024

This presentation offers a comprehensive overview of the entire process involved in the fabrication of C-LFP/LMFP-based lithium-ion batteries , from the initial elements in the mine to the assembly of the final systems that power EVs or energy storage. C-LiFePO4 (C-LFP) and C-LiMn
x
Fe1-x
PO4 (x=0.1 to 1) (C-LMFP)-based technologies represent an increasing segment of lithium-ion batteries (LIBs) for electric vehicles (EVs) and energy storage due to desirable properties such as high safety, low cost and long cycle life. Our review encompasses the entire LIB development process, starting from mineral resources, including Li, Fe, Mn, and PO4, their global reserves; mining procedures, followed by the preparation procedures for the main Fe- and Mn-containing precursors (Fe0, FexOy, FePO4, FeSO4, and MnSO4). Their utilization in LIBs and their incidence on the electrochemical performance of the final active cathode materials are also analyzed. We outline pioneering synthesis methods for olivine production lines, with emphasis on hydrothermal liquid-state synthesis, molten-state synthesis, and solid-state synthesis. We conclude with electrode engineering and the design and optimization of electrolytes in view of applications to systems.
(2023-2024 ECS Toyota Young Investigator Fellowship Award) Ultrafast Electrodeposition of Faceted Li Metal
Authors: Li Yuzhang
Published: December 2024

Electrochemical deposition of metals with precise morphological and chemical control is of fundamental importance to a broad range of electrochemical systems, including energy storage, large scale manufacturing, electronics, and electrocatalysis. For non-reactive metals (e.g. Ni, Pt), electroplating is a commercially established process that gives the desired control of deposition morphology and chemistry. However, deposition of reactive metals (e.g. Li, Na) critical for enabling next-generation batteries is complicated by metal surface corrosion that occurs concurrently with metal deposition, making such electrodeposition processes neither well-understood nor well-controlled. This work highlights the electrodeposition of lithium (Li), a reactive metal anode plagued with uncontrolled dendritic morphologies and surface corrosion, both of which are intimately linked and occur simultaneously. Despite tremendous research efforts to mitigate these issues, common literature descriptions of Li metal deposits (e.g. “chunky”, “pancake”) and their corrosion films (e.g. “strong”, “stable”) are ill-defined and often qualitative, highlighting our incomplete understanding of the deposition process and hindering the practical application of high energy battery chemistries enabled by Li metal. Our work seeks to bridge this critical gap in understanding by solving the fundamental challenge of (1) decoupling simultaneous electrodeposition from surface corrosion of reactive metals and (2) observing their reactive nanoscale interface.
(Invited) Redefined Battery Science and Engineering after 100 Years of Debye-Hückel Theory
Authors: Yamada Atsuo
Published: December 2024

In any electrochemical system, electrode potential is the central variable that regulates the driving force of redox reactions. However, quantitative understanding of the electrolyte dependence has been limited to the classic Debye-Hückel theory that approximates the Coulombic interactions in the electrolyte under the dilute limit conditions. Therefore, accurate expression of electrode potential for most of practical electrochemical systems has been a holy grail of electrochemistry research for over a century. Here we show that the ‘liquid Madelung potential’ based on the conventional explicit treatment of solid-state Coulombic interactions enables quantitatively accurate expression of the electrode potential, with the Madelung shift obtained from molecular dynamics reproducing a hitherto-unexplained huge experimental shift for several battery electrode. Furthermore, incorporating the effects of entropy and polarization dynamics could polish the theoretical model to perfectly fit the experimental data. Thus, a long-awaited method for the description of the electrode potential in any electrochemical system is now available after 100 years of classical Debye-Hückel theory.

[1] P. Debye & E. Hückel, Physikalische Zeitschrift, 24, 185 (1923), [2] N. Takanaka, et al., and A. Yamada, Denki Kagaku, 91, 140 (2023) [3] S.Ko, et al., and A. Yamada, Next Energy, 100014 (2023), [4] S. Ko, et al.,and A. Yamada, Nature Sustain., 6, 1705 (2023), [5] N. Takenaka, et al., and A.Yamada, Nature Comm., 15, 1319 (2024)
How Low Temperature Heat Transfer Fluids Improve Localized High-Concentration Electrolytes for Lithium-Metal Batteries
Authors: Weintz Dominik , Woelke Christian , Winter Martin , Cekic-Laskovic Isidora
Published: December 2024

The rising deployment of portable devices and electric vehicles has accelerated the development of high energy-dense batteries and revived interest in lithium metal as an anode material in recent years. However, by employing the widely-used organic carbonate-based electrolyte formulations in lithium-metal batteries (LMBs), whisker-like Li deposits emerge during galvanostatic cycling, precipitating a rapid active material degradation.1 Consequently, researchers have shifted their focus towards novel electrolyte formulations aimed at facilitating a dense Li deposition and prolonging the cycle life of LMBs. A promising approach is the application of localized high-concentration electrolytes (LHCEs) due to their unique solvation structure, causing the formation of an effective anion-derived Solid Electrolyte Interphase (SEI) and a dense Li deposition morphology.2–5 One of the remaining challenges for this novel electrolyte concept is the low ionic conductivity and the resulting declining galvanostatic cycling performance at higher current densities (> 1 mA cm-2), thus making the increase of the ion mobility crucial to enable LHCEs to become viable electrolyte solutions for LMBs.

In our study, we investigated inexpensive heat transfer fluids as effective co-diluents for LHCEs employed in LMBs. Incorporating these low-cost fluids into the electrolyte formulation results in lower viscosity and enhances molecular diversity, thereby improving transport properties and causing superior fast-charging capabilities of the resulting LMB chemistry. While the introduction of these novel co-diluents appears to have no discernible effect on the composition of the interphase layer formation, their presence promotes a more uniform lithium deposition morphology, particularly under higher charging rates. Additionally, the non-flammable nature of these components enhances the safety profile of the LMBs, rendering the novel components as multifunctional co-diluents for LHCEs and concurrently improving several crucial properties of the resulting electrolyte formulation.

References:

Horstmann, B. et al. Strategies towards enabling lithium metal in batteries: interphases and electrodes. Energy Environ. Sci.
14, 5289–5314 (2021).

Cao, X., Jia, H., Xu, W. & Zhang, J.-G. Review—Localized High-Concentration Electrolytes for Lithium Batteries. J. Electrochem. Soc.
168, 010522 (2021).

Ren, X. et al. Enabling High-Voltage Lithium-Metal Batteries under Practical Conditions. Joule
3, 1662–1676 (2019).

Ren, F. et al. Solvent–Diluent Interaction-Mediated Solvation Structure of Localized High-Concentration Electrolytes. ACS Appl. Mater. Interfaces
14, 4211–4219 (2022).

Angarita-Gomez, S. & Balbuena, P. B. Ion mobility and solvation complexes at liquid–solid interfaces in dilute, high concentration, and localized high concentration electrolytes. Mater. Adv.
3, 6352–6363 (2022).
Influence of Oxygen Defects on Electrochemical Performance of Ni-Rich Layered Oxides for Future Lithium-Ion Batteries
Authors: Henseler David , Vettori Kilian , Schröder Steffen , Nakamura Takashi , Henss Anja , Janek Jürgen
Published: December 2024

Ni-rich layered cathode active materials (CAMs) are promising candidates for application in lithium-ion batteries due to their high reversible capacity. To further improve the performance of lithium-ion batteries, changing the transition metal composition in CAMs is a good approach to gain a higher capacity, better capacity retention as well as higher rate capability and safety. The oxygen lattice has been considered and widely accepted to be electrochemically inactive, even though it plays a key role in the phase transformations that occur at high degrees of delithiation, as oxygen is released during these high delithiation states. In addition, released oxygen can cause thermal runaway, by exothermic reaction with electrolyte 1,2. However, the effect of oxygen defects and vacancies on the electrochemical performance of cathode active materials in lithium-ion batteries has been scarcely investigated. Research has mainly focused on lithium-rich layered materials, where oxygen vacancies have led to improved battery performance in terms of rate capability, higher discharge capacity and reduced oxygen evolution 3. However, many of these publications suffer from an unprecise content of oxygen deficiencies within the cathode active material with large errors. In this work, a solid-state reactor for electrochemical extraction of oxygen is used to obtain an accurate oxygen deficiency with low error for Ni-rich layered NCM 811 4. Using this process, 1 mol%, 2 mol% and 5 mol% oxygen deficient NCM 811 are produced and (electro)chemically characterized. The effect of oxygen defect concentration on discharge capacity, capacity retention, rate capability and structural stability is investigated in liquid cells. In addition, electrochemical impedance spectroscopy (EIS) is used to reveal changes in electrode resistances. To obtain the cathode impedance only, a three-electrode setup is used, which utilizes a μ-reference electrode made of gold wire.

References

1 R. Jung, M. Metzger, F. Maglia, C. Stinner and H. A. Gasteiger, J. Electrochem. Soc., 164, A1361 (2017).

2 R. Jung, P. Strobl, F. Maglia, C. Stinner and H. A. Gasteiger, J. Electrochem. Soc., 165, A2869 (2018).

3 B. Qiu, M. Zhang, L. Wu, J. Wang, Y. Xia, D. Qian, H. Liu, S. Hy, Y. Chen, K. An, Y. Zhu, Z. Liu, and Y. S. Meng, Nat. Commun., 7, 12108 (2016).

4 T. Nakamura, H. Gao, K. Ohta, Y. Kimura, Y. Tamenori, K. Nitta, T. Ina, M. Oishi and K. Amezawa, J. Mater. Chem. A, 7, 5009 (2019).
Doping Engineering of Manganese on Cobalt Oxide in Particle Size-Controllable Compound Anode for Lithium-Ion Batteries
Authors: Jung Ji-Won , Na Hyunmin , Kim Na-Yeong , Lee Ho-Jin , Park Jeong-Ho , Seo Jae-Woo , Choi Seon-Jin , Lee Jiyoung , Kim Hyun-Suk , Cheong Jun Young
Published: December 2024

Lithium-ion batteries (LIBs) are of significant importance in facilitating the functionality of portable electronic devices and electric vehicles due to their exceptional energy density and extended lifespan. This study introduces a novel approach to enhance the efficiency of lithium-ion batteries (LIBs) by employing nanofibers of cobalt oxide (Co3O4) doped with manganese. The focus of this study revolves around the reduction in grain size, increase in ionic transport, and improvement in cycling stability. The application of a tailored methodology for the production of Mn-doped Co3O4 nanofibers leads to a deliberate decrease in grain size, which consequently enhances the quantity of available active sites for the process of lithium-ion intercalation. Consequently, this phenomenon enhances the rate of reaction kinetics during both the charging and discharging procedures. The incorporation of manganese dopants into the Co3O4 nanofiber architecture improves the promotion of lithium-ion diffusion, mitigates charge transfer resistance, and enhances cycling performance. The implications of the study's findings are significant for the advancement of anode materials with improved performance, as well as for the exploration of anode materials utilizing nanofibers. This research offers tremendous contributions to the field of environmentally sustainable energy technologies by providing valuable insights into the development and engineering of advanced lithium-ion batteries.
Preserving the Lithium Affinity of Thin Li-Alloy Coatings on Current Collectors for No-Excess Lithium Metal Batteries
Authors: Seo Jiyeon , Lee Jiwon , Lee Hongkyung
Published: December 2024

Zero-excess lithium metal batteries (ZE-LMBs) are at the forefront of battery technology, boasting unparalleled energy density. The lack of materials to host lithium, however, leads to unregulated growth of lithium dendrites on the copper current collectors. This causes a persistent reduction in the lithium supply and significant degradation of the electrolyte, which restricts the battery's efficiency over time. This research introduces the use of extremely thin (~50 nm) coatings made of six different metals (Cu, Ag, Au, Pt, W, and Fe) on copper bases. The aim is to explore how these coatings can contribute to the development of current collectors that support stable operation of ZE-LMBs. The study reveals that coatings made from Ag, Au, and Pt, as opposed to those made from Cu, W, and Fe, increase the surface's affinity for lithium, effectively reducing the growth of lithium dendrites and enhancing the reversibility of lithium deposition. Specifically, platinum (Pt)-coated copper collectors are able to keep their lithiophilic surface properties through numerous cycles of lithium deposition and removal. This is due to their ability to preserve the integrity of the initial coating layer, leading to improved battery life and performance in ZE-LMBs. The findings underscore the critical role of selecting the right lithium-alloy metals for coatings to maintain a lithiophilic surface, control lithium plating without dendrites, and enhance the electrochemical stability of ZE-LMBs.
Lithium Dendrite-Free High-Voltage Lithium-Ion Pouch Cell Enabled By Ambi-Functional Additive
Authors: Vu Dung Tien Tuan , Im Jinsol , Kim Jaehee , Han Jisoo , Chung Gyeongjun , Nguyen Giang Thi Huong , Junhyeok Seo , Kim Minjae , Hwang Eui Hyung , Kwon Young Gil , Shin Jae Wook , Cho Kuk Young , Song Seung-Wan
Published: December 2024

Elevating the charge cut-off voltage beyond traditional 4.2 V is a commonly accepted technology to increase the energy density of Li-ion batteries (LIBs), but the risk of Li-plating and dendrites and fire hazard increases as well. A suggested method to solve these issues is to design functional electrolyte component to form a surface-passivating solid electrolyte interphase (SEI) layer at graphite anode earlier than the occurrence of Li-plating and dendrites. The use of ambi-functional additive, which forms SEI simultaneously at both cathode and anode, is a key to enable a dendrites-free and well-working high-voltage LIB. Herein, we report a novel ambi-functional additive, pentaerythritol disulfate, at 1 wt% without any other additive. We show the feasibility and high impacts of the additive in forming robust SEI layers at LiNi0.5Co0.2Mn0.3O2 (NCM523) cathode and graphite anode in 1 Ah-level pouch cell under 4.4 V, 25 °C and 0.1 C rate, which mitigates the high-voltage instability, metal-dissolution and cracks on NCM523 particles, and prevents Li-plating and dendrites at graphite anode. Ambi-functional additive-derived improved capacity retention with respect to base electrolyte offers a promising path toward the design of practical high-energy LIBs.
Ethereal Based Electrolytes for Ultrastable LiNi0.8Mn0.1Co0.1O2 (NMC811)||Si Full Cells
Authors: Wu Xianyang , Li Xinlin , Amine Khalil , Wu Dezhen , Li Tianyi , Su Chi Cheung , Yang Zhenzhen , Ingram Brian J.
Published: December 2024

With its impressive specific capacity of 3579 mAh/g (when alloyed into Li15Si4 at room temperature), Silicon (Si) anode is widely regarded as an ideal alternative to graphite anodes. However, its commercial viability is still hampered by rapid capacity degradation. Liquid electrolytes based on ethereal solvents such as dimethoxyethane (DME) and diglyme (DG) have demonstrated excellent long-term cycling performance in Li||Si half cells. However, their utilization in full cells like LiNi0.8Mn0.1Co0.1O2 (NMC811)||Si remains limited due to their relatively low oxidation stability at the NMC811 side.

In this investigation, innovative electrolyte systems employing Lithium bis(fluorosulfonyl)imide (LiFSI) salt were developed. Various ethereal solvents including DME, DG, 2,2-dimethyl-3,6,9,12-tetraoxa-2-silatridecane (1NM3), and self-synthesized 1,1,1-trifluoro-2-(2-(2-(2,2,2-trifluoroethoxy)ethoxy)ethoxy)ethane (FDG) were methodically examined. Initially, density functional theory (DFT) calculations were utilized to compare the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) levels of these solvents, revealing that 1NM3 and FDG exhibited lowered HOMO levels, suggesting enhanced oxidative stability on the NMC811 cathode side compared to DME and DG. Subsequently, the solvation structure of the prepared electrolyte systems was investigated via Fourier Transform Infrared Spectroscopy (FTIR). The addition of a -CF3 functional group and the weaker dissociation capacity of FDG resulted in significant cation-anion aggregates (AGGs) within the FDG-based electrolytes, while no such AGGs were observed in the DME, DG, and 1NM3-based electrolytes. Electrochemical properties and performances were further evaluated through systematic tests on Li||Al, Li||Si half cells, and LiNi0.8Mn0.1Co0.1O2 (NMC811)||Si full cells. Differential capacity (dQ/dv) profiles from Si||Li half cells revealed their distinct reduction behavior on the Si anode. Potentiostatic hold tests on NMC811||Li half cells demonstrated the superior oxidative stability of FDG-based electrolytes up to 4.5 V vs. Li/Li+. Long-term cycling results confirmed significant improvements with 1NM3 and FDG solvents in NMC811||Si full cells, maintaining a high specific capacity of 900 mAh/g after 500 cycles for the FDG-based electrolytes. Further analysis of the interphases formed on electrodes via depth-profiling X-ray photoelectron spectroscopy (XPS) indicated enhanced oxidative stability on the NMC811 cathode and improved solid electrolyte interphase (SEI) on Si anodes, leading to enhanced electrochemical performance. Thus, our exploration of these ethereal electrolytes has paved the way for strategic advancements in crafting novel electrolytes specifically designed for Si anodes, highlighting their remarkable long-term cycling capabilities within NMC811||Si full cells.
Localized High-Concentration Electrolytes for High-Voltage Disordered Rocksalt Cathode Materials
Authors: Ahmed Ridwan , Koirala Krishna Prasad , Wang Chongmin , Xu Wu
Published: December 2024

With the pursuit of high energy-density battery systems, cathode materials with high specific capacity and high working voltage are of high interest. Among the transition metal oxide cathode materials, lithium (Li)-rich cation disordered rock salt (DRX) cathode materials are promising candidates for next-generation high-energy-density Li batteries because they offer high specific capacities and cost benefits. Particularly, the manganese (Mn)-based DRXs show more promise due to the utilization of earth abundant material and good thermal stability of Mn. However, these cathodes often face big challenges when cycled in the state-of-the-art LiPF6/carbonate-based electrolytes at voltages up to 4.8 V. These include severe side reactions between the cathode and the electrolyte, transition metal dissolution and structural instability of the cathode particles, all of which result in fast capacity fading. In this work, we developed advanced localized high-concentration electrolytes (LHCEs) to mitigate these problems and enable stable cycling of a DRX cathode material, Li1.2Mn0.6Ti0.2O2 (LMTO). The LHCEs demonstrate high voltage stability of 4.9 V vs. Li/Li+ and capability of forming an ultrathin and stable cathode-electrolyte interphase. Consequently, Li||LMTO half cells with the optimal LHCE exhibit increased capacity, enhanced cycling stability and superior rate capability when compared to the cells with the conventional electrolyte. This work sheds the light of electrolyte development to enable practical DRX cathode-based high-energy Li batteries.