bluuebunny/crossref_metadata_2025_split huggingface dataset:
Azo-Integrated Covalent Organic Frameworks As Electrodes for Lithium-Ion Batteries
Authors: Singh Vikram , Kim Jaewook , Kang Bora , Moon Joonhee , Kim Sujung , Kim Woo Youn , Byon Hye Ryung 
Published: July 2022

Covalent Organic Frameworks (COFs) are two-dimensional, porous, and crystalline organic structures. The well-established frameworks provide ordered mesopores, structural stability, high density, and negligible solubility, which are particularly attractive for battery electrodes. By integrating a redox-active azo group to COFs, we designed positive organic electrodes and applied these electrodes for nonaqueous Li-ion batteries. The azo group can undergo two electrons transfer, whereas its reversibility and stability are highly dependent on adjacent functional groups [1,2]. We developed three azo-integrated COFs with three different linkages, -ketoenamine, imine, and thiazole-fused ring. These azo-COFs had identical hexagonal P6/m space groups, ~3 nm of pore size, and 600~1000 m2 g–1 of surface area. However, the redox chemistries of azo groups were remarkably distinct from the linkages. The-ketoenamine and imine based azo-COFs showed irreversible azo reactions, resulting in poor capacity retention. In contrast, the fully conjugated COF containing the thiazole-fused ring rendered excellent cycling stability showing 5000 cycles at 10 C. The reversible azo reaction was also demonstrated by using operando Raman spectroscopy. This result corresponded to the single and sharp redox wave at a formal potential of ~1.7 V vs. Li/Li+, suggesting the one-step two electrons transfer. The solid electrolyte interphase (SEI) was formed at the initial cycles only, which could protect the COF surface and inhibit the continuous decomposition of the electrolyte solution. Electrochemical impedance spectroscopy (EIS) revealed the low charge transfer resistance (~18 Ω), which decreased further after 20 cycles (~6 Ω). The mass transport region in the EIS curve was retained, indicating the access of Li+ to the bulk COF structure through mesopores for cycling. In the presentation, I will discuss the details of COF designs and the role of linkages enhancing the reversible and stable redox reactions in Li-ion cells.

References:

[1] Luo, C., Borodin, O., Ji, X., Hou, S., Gaskell, K.J., Fan, X., Chen, J., Deng, T., Wang, R., Jiang, J. and Wang, C. PNAS, 2018, 115, 2004-2009.
[2] Luo, C., Xu, G.L., Ji, X., Hou, S., Chen, L., Wang, F., Jiang, J., Chen, Z., Ren, Y., Amine, K. and Wang, C., Angew. Chem. Intl. Edn.
2018, 57, 2879-2883.

Figure 1
Development of a LiMnFePO4 / Li4Ti5O12 2Ah Pouch Cell: An Example of the Effective Integration of New Materials
Authors: Dontigny Martin , Perea Alexis , Asakawa Yuichiro , Zaghib Karim , Daigle Jean-Christophe 
Published: July 2022

One of the most promising approaches for limiting climate change is the use of alternative and greener sources of energy (wind, solar, etc.). The electricity generated from these sources fluctuates, however, and a storage solution is needed. The advent of energy storage for wind farms, solar plants, etc., requires a new generation of batteries. It is therefore imperative that a battery with high energy density, a longer life cycle and improved safety be developed.
In this paper, we describe our efforts to develop a safe and long-life cycle LiMnFePO4 (LMFP)/Li4Ti5O12 (LTO) 2Ah pouch cell. One of the major challenges faced in this pursuit was gas evolution during cycling. Various side reactions with active materials resulted in the generation of gas during cycling. To circumvent this, we implemented several mitigation strategies. To combat electrolyte degradation (1.0 M LiPF6 in carbonate solvents) due to Mn2+ dissolution in LMFP, we integrated a new class of polymer as a binder in the cathode preparation, which effectively decreased the degradation during cycling. This polymer also has high voltage stability.1 At the battery’s negative electrode, we developed a new carbon coating method on LTO that minimizes electrolyte degradation and optimizes high C-rate preformances, especially fast charging performances.2 Although these new materials reduce gas evolution, they do not eliminate it. Therefore, we developed the first polymer capable of trapping the carbon dioxide, major component of gases generated during cycling and, in turn, preventing pouch cell inflation. This polymer was integrated in a pouch cell in the form of an insoluble trapping sheet.3 Although relatively simple, this technology made the pouch cells safer. This unique approach is versatile and can be implemented in pouch cells with any type of chemistry when gas scavenging is required. The 2Ah pouch cells did not experience any inflation during extensive cycling and aging. Cells cycled more then 750 cycles at 45oC with a rate of 1C – 1C before reaching 80% retention capacity.
Reference
(1) Daigle, J.-C.; Asakawa, Y.; Zaghib, K. Polymer additives and their use in electrode materials and electrochemical cells. WO2020061710A1, 2020.
(2) Daigle, J.-C.; Asakawa, Y.; Beaupre, M.; Gariepy, V.; Vieillette, R.; Laul, D.; Trudeau, M.; Zaghib, K. Boosting Ultra-Fast Charge Battery Performance: Filling Porous nanoLi4Ti5O12 Particles with 3D Network of N-doped Carbons. Sci. Rep.
2019,
9 (1), 1-9, DOI: 10.1038/s41598-019-53195-1.
(3) Daigle, J.-C.; Asakawa, Y.; Perea, A.; Dontigny, M.; Zaghib, K. Novel polymer coating for chemically absorbing CO2 for safe Li-ion battery. Sci. Rep.
2020,
10 (1), 10305, DOI: 10.1038/s41598-020-67123-1.
(Invited) Battery Design for Fast Charging
Authors: Li Jianlin 
Published: July 2022

Lithium-ion batteries (LIBs) has been broadly applied in electric vehicles (EVs) and the market adoption of EVs can be further improved with enhanced fast charging capabilities. The state-of-the-art chemistries, such as LiNixMnyCo1-x-yO2 (NMC) and graphite, are capable for fast charging. However, the electrodes are limited to thin coating due to mass transport limitation, which results in low energy density and high cost [1]. For example, the United States Department of Energy (DOE) issued a call for proposal in 2017 to enable extreme fast charging with a target of cell energy density higher than 180 Wh/kg which is much lower than that under normal application.
The energy density of LIBs depends on the materials properties and cell engineering. In this presentation, the impact of cell design on energy density under fast charging will be discussed. Specifically, design in electrodes, current collectors, electrolyte, and separator will be elaborated to show their correlation to fast charging application [2-3].

Acknowledgment

This research at Oak Ridge National Laboratory (ORNL), managed by UT Battelle, LLC, for the U.S. Department of Energy under contract DE-AC05-00OR22725, was sponsored by the Office of Energy Efficiency and Renewable Energy (EERE) Vehicle Technologies Office (VTO) and Advanced Manufacturing Office (AMO).

References

[1] Colclasure, A. M.; Dunlop, A. R.; Trask, S. E.; Polzin, B. J.; Jansen, A. N.; Smith, K. Requirements for Enabling Extreme Fast Charging of High Energy Density Li-Ion Cells while Avoiding Lithium Plating. J. Electrochem. Soc.
2019, 166, A1412-A1424.
[2] Parikh, D.; Christensen, T.; Li, J.; Elucidation of separator effect on energy density of lithium-ion batteries, J. Electrochem. Soc.
2019, 166 (14), A3377.
[3] Parikh, D.; Christensen, T.; Li, J.; Correlating the influence of porosity, tortuosity, and mass loading on the energy density of LiNi0. 6Mn0.2Co0.2O2 cathodes under extreme fast charging (XFC) conditions, Journal of Power Sources, 2020, 474, 228601.
Nanoscale Ionic Materials for Nafion Based Nanocomposites Membranes As Single Lithium-Ion Conducting Polymer Electrolytes for Lithium Sulfur Batteries
Authors: Nicotera Isabella , Lufrano Ernestino , Simari Cataldo , Enotiadis Apostolos , Brutti Sergio , Nojabaee Maryam , Sievert Brigitta 
Published: July 2022

Currently, rechargeable batteries with the lithium–sulfur (Li–S) chemistry has attracted great interest as one of the most promising candidates for next generation electrochemical energy storage systems. Research into these high energy density devices is critical to the development of thinner, lighter, and lower cost battery systems. One of the biggest obstacles for practical applications of Li-S batteries is caused by the soluble nature of the highly ordered lithium polysulfides (Li2Sn) in the organic electrolytes and induce a so-called “shuttle eﬀect”. A solid-state electrolyte (SPEs) could be a valid alternative in terms of reducing the polysulﬁdes dissolution and shuttle, as well as to protect the lithium metal anode and to minimize dendrite formation, which is beneﬁcial for improving the safety and cycle life of Li−S batteries. SPEs are typically dual-ion conductor systems both cations and anions are mobile and cause a concentration polarization leading to poor performances of batteries. Recently, single lithium-ion conducting solid polymer electrolytes (SLIC-SPEs) have been proposed for polymer electrolytes, where anions are covalently bonded to the polymer, inorganic backbone, or immobilized by anion acceptors and only the Li+ cation will contribute to a permanent flow of charge. They have advantages over conventional dual-ion conducting SPEs such as unity transference number, absence of harmful effect of anion polarization, extremely low rate of Li dendrite growth and immobilization of the lithium polysulfides in the lithium-sulfur (Li-S) batteries. Polymer electrolytes based on ionomers (e.g., Naﬁon) with easily ionizable groups (e.g., sulfonic groups covalently bonded to the polymer side-chains, −CF2SO3
−) are promising thanks to the high concentration of weakly coordinating anions (counterions). In this work, lithiated Naﬁon and Naﬁon-nanocomposites membranes based on Nanoscale Ionic Materials (NIMs) were synthesized, and their ionic conductivity and lithium transference number were investigated in common nonaqueous organic solvents (EC/PC and Glymes).
A thorough and systematic study of the lithium-ion transport was conducted by p 1H and 7Li pulsed ﬁeld gradient (PFG) NMR spectroscopy and electrochemical impedance spectroscopy (EIS), while the mechanical properties of the film electrolytes have been tested by dynamic mechanical analysis (DMA) in a wide temperature range. The electrochemical studies have been conducted both in Li/Li symmetric cell and in secondary Li-S cells. The preliminary results are very interesting, showing ionic conductivities of the order of 5 × 10-4 S/ cm at 25°C satisfactory properties in terms of stability window and stability of the lithium stripping. The lithium transport number is very close to unity thus confirming the complete immobilization of the negative charge carriers.
Origins of the Fast-Charging Abilities of Niobium Containing Wadsley-Roth Phases
Authors: Baek Sun Woon , Wyckoff Kyra E. , Preefer Molleigh , Saber Muna , Van der Ven Anton , Seshadri Ram , Pilon Laurent 
Published: July 2022

Lithium-ion batteries (LIBs) featuring high energy density have received particular attention in recent years due to their promise as electrical energy storage devices for electric vehicles and portable electronic devices. However, most of the commercial LIBs use graphite anode which suffer from the formation of solid-electrolyte interface (SEI) layer. Moreover, the poor performance of graphite anodes at high C-rates limits their application for fast-charging LIBs. To address the challenges associated with graphite anodes, niobium-containing Wadsley-Roth shear phase materials have been suggested. Thanks to the redox potential of Nb4+
(above 1 V versus Li/Li+), the niobium containing Wadsley-Roth shear phase materials avoid SEI formation. Furthermore, a combination of edge-shared and corner-shared octahedra in this type of shear phase materials forms many tunnel-like regions where Li-ions can rapidly diffuse during lithiation and delithiation. In fact, niobium-containing Wadsley-Roth shear phase materials show impressive cycling performance as fast-charging battery materials and maintain more than 50 % of their theoretical capacity at C-rate of 10 C.
This study aims to understand the fast-charging capability of niobium containing Wadsley-Roth shear phase materials accompanied by ion ordering in the application of LIBs. In addition, it aims to provide experimental evidence to elucidate the occurrence of Li-ion ordering in this type of shear phase materials. To do so, galvanostatic cycling and cyclic voltammetry were performed on selected niobium-containing Wadsley-Roth shear phase materials including TiNb2O7, PNb9O25, VNb9O25, and NaNb13O33. In addition, open circuit voltage and entropic potential of those materials were measured. The results show that ion ordering characterized by a tilde-shaped fluctuation in entropic potential was observed in all tested niobium containing Wadsley-Roth shear phase materials. Furthermore, the results indicate that the b-value approaching 0.5 corresponded to the first order transition accompanied by a two-phase coexistence while the b-value approaching 1 corresponded to the ordering of Li-ions. This analysis implies that the ion ordering phenomena can enhance the fast-charging capability of the material. This study provides valuable insights for fast-charging battery materials.
(Digital Presentation) Evaluating the Corrosivity of Liquid LiPF6 Electrolytes with Nickel-Coated Mild Steel Used in the Manufacturing of Li-Ion Cells for Energy Storage
Authors: Smith Scott R. , Sahota Preet , Wood Bryan D. , Way Brian 
Published: July 2022

Effects of electrolyte degradation on cell performance and corrosion of cell components, e.g. current collectors, are topics that have been reported in the literature.1,2 Recently, it has been reported that water contamination of LiPF6 liquid electrolytes can lead to salt degradation, generating difluorophosphoric acid (DFPH) and hydrofluoric acid (HF).3 With strict quality control of the moisture content in individual components and the use of dryroom conditions for cell assembly the risk of moisture contamination can be practically eliminated. When moisture is allowed to enter the cell in controlled research samples, dark stains indicative of pitting type corrosion have been observed on the inside of mild steel cans that are used to house cylindrically wound electrodes (see Figure 1 inset). Motivation to understand the underlying corrosion mechanism and the influential factors is important to help lower the risk of occurrence in manufacturing further.
The use of a simple corrosion plate cell to study the susceptibility of a mild steel sample immersed in a LiPF6/EC/DMC (15/25/60 wt%) electrolyte will be discussed, with a focus on measured corrosion potentials, E
corr, and current densities, j
corr, extracted from the Tafel region of a potentiodynamic scan. Observations on the influence of acid degradation products in the electrolyte on the corrosion susceptibility of the mild steel will be discussed and applied to study select electrolyte additives previously reported in literature. Early results have shown that additives that scavenge HF and/or water directly can effectively suppress j
corr, as shown in Figure 1, whereas additives that increased DFPH generation had no apparent effect.

References:

[1] Myung, Hitoshi, and Sun. J. Mater. Chem., 2011, 21, 9891-9911.
[2] Ma et al. J. Phys. Chem. Lett. 2017, 8, 5, 1072–1077
[3] Wiemers-Meyer, Winter, and Nowak. Phys. Chem. Chem. Phys., 2016, 18, 26595-26601.
Figure 1: Bar graph of corrosion current, j
corr, measured for a LiPF6/EC/DMC (15/25/60 wt%) control electrolyte with 2500 ppm of water contamination, as well as with ~2 wt% of an additive that formed more DFPH than the control, an additive that formed more DFPH and HF than the control, and an additive that scavenged HF. Inset: Optical image of the inside of a mild steel can disassembled after 14 days of 60°C storage at top of charge illustrating dark regions indicative of steel corrosion.

Figure 1
Concentration Polarization in Batteries: Theory, Experimental Verification and Practical Relevance
Authors: Stolz Lukas , Winter Martin , Kasnatscheew Johannes 
Published: July 2022

Apart from particle-type inorganic solid electrolytes, organic, i.e. solid polymer electrolytes (SPEs), are of high potential interest for the realization of next generation Li metal batteries, given their abundance, low cost, electrochemical stability and wetting ability.(1, 2)
Nevertheless, the poor ion transport in SPEs limits the battery operation to elevated temperature and/or lower rates only and remains main focus of R&D.(3) Besides the internal-resistance induced polarizations (overpotentials), it is the onset of concentration polarization, which determines the operation limit in terms of e.g. temperature and current density.
This work aims to practically unravel the mystery of concentration polarization by means of simple electrochemical experiments in Li||Li cells and mathematical descriptions via the well-known Sand and diffusion equations.(4, 5) The conformity of theory and experiments allows valuable mathematical determinations and predictions of parameter and operation limits. For example, these equations can predict the practical onset of concentration polarization. Also, parameter can be obtained, e.g. diffusion coefficients, based on the experimentally observed polarization onsets.
The relevance of concentration polarization including its impact on the cell performance even in high voltage LiNi0.6Mn0.2Co0.2O2 (NMC622)||Li cells is demonstrated by experimentally varying the applied current, the salt concentration, the temperature as well as the cell set-up (e.g. electrolyte thickness and electrode area-oversizing).(6) The validity of these relations is additionally confirmed in state-of-the-art liquid, i.e. LiPF6/carbonate-based, electrolytes and the special case of single-ion conducting electrolytes is discussed.

L. Stolz, S. Röser, G. Homann, M. Winter and J. Kasnatscheew, The Journal of Physical Chemistry C, 125, 18089 (2021).

J. Mindemark, M. J. Lacey, T. Bowden and D. Brandell, Prog. Polym. Sci., 81, 114 (2018).

J. Janek and W. G. Zeier, Nature Energy, 1, 16141 (2016).

L. Stolz, G. Homann, M. Winter and J. Kasnatscheew, Data in Brief, 34, 106688 (2021).

L. Stolz, G. Homann, M. Winter and J. Kasnatscheew, Materials Today, 44, 9 (2021).

L. Stolz, G. Homann, M. Winter and J. Kasnatscheew, ChemSusChem, 14, 2163 (2021).

Figure 1
Tetraglyme Based Electrolytes Enabled Excellent Cycling of Sodium Metal
Authors: LE Phung M-L , Jin Yan , Wang Chongmin , Engelhard Mark H. , Zhang Ji-Guang 
Published: July 2022

Sodium metal is a promising anode for batteries because of its high theoretical specific capacity (1165 mAh g-1) and great abundance and low cost. However, fundamental issues such as dendrite formation, “dead sodium” accumulation during cycling, fast SEI dissolution or continuous SEI growth bring challenges for stabilizing reversibility of sodium metal anode. Recent advances in electrolyte engineering and development of highly stable cathode materials have enables sodium metal batteries reaching high CE (>99 %) at room temperature1-5.
Herein, we report a feasible pathway toward further stabilization of sodium metal anode using tetraglyme solvent (TEGDME) based electrolyte with various sodium salts (NaBF4, NaPF6, NaTFSI, NaFSI, NaClO4, NaOTf). It is demonstrated that a Na||Cu cell exhibited an average Coulombic efficiency of 99.9 % over 200, 850, and 1000 plating-stripping cycles when an electrolyte of 1M NaOTf in TEGDME, 1M NaPF6 in TEGDME, and 1M NaBF4 in TEGDME were used, respectively. Furthermore, 1M NaBF4 in TEGDME electrolyte also enabled excellent cycling stability of Na||Na3V2(PO4)2 batteries at high rate (1 C) for 1000 cycles with capacity retention of 90.8 %.

References

Seh, Z. W.; Sun, J.; Sun, Y.; Cui, Y. A Highly Reversible Room Temperature Sodium Metal Anode. ACS Cent. Sci. 2015, 1, 449−455.

Cao, R.; Mishra, K.; Li, X.; Qian, J.; Engelhard, M. H.; Bowden, M. E.; Han, K. S.; Mueller, K. T.; Henderson, W. A.; Zhang, J.-G. Enabling Room Temperature Sodium Metal Batteries. Nano Energy
2016, 30, 825−830.

Zheng, J.; Chen, S.; Zhao, W.; Song, J.; Engelhard, M.H.; Zhang, J.G. Extremely Stable Sodium Metal Batteries Enabled By Localized High-Concentration Electrolytes, ACS. Energy. Lett.
2018, 315−321.

Goktas, M.; Bolli, C.; Buchkheim, J.; Berg, E. J; Novak, P.; Bonilla, F.; Rojo, T.; Komaba, S.; Kubota, K.; Adelhem, P.; Stable and Unstable Diglyme-Based Electrolytes for Batteries With Sodium or Graphite as Electrode., ACS Appl. Mater. Interfaces
2019, 11, 32844-32855.

Le, P.M.L; Vo, D.T; Pan, H., Yan, J.; He, Y.; Cao, X.; Nguyen, H.V; Engelhard, M.H; Wang, C.; Xiao, J.; Zhang, J-G., Excellent Cycling Stability of Sodium Anode Enabled by a Stable Solid Electrolyte Interphase Formed in Ether-Based Electrolytes, Adv. Funct. Mater. 2020, 30, 2001151

Acknowledgement

This work is supported by the Assistant Secretary for Energy Efficiency and Renewable Energy, Office of Vehicle Technologies of the US Department of Energy (DOE) through the Advanced Battery Materials Research (BMR) program under contract no. DE-AC05-76RLO1830.