bluuebunny/crossref_metadata_2025_split huggingface dataset:
Design and Syntheses of New Dipolar Organic Aprotic Solvents for 5V Lithium-Ion Batteries
Authors: Flamme Benjamin , Haddad Mansour , Phansavath Phannarath , Vidal Virginie , Chagnes Alexandre 
Published: February 2020

The development of new technologies for electrochemical energy storage is one of the main challenge of the next decades. Many hopes now rely on lithium-ion batteries (LiBs) that have invaded the market of laptops and which appear to be the best choice with the short time for electric vehicles, and perhaps for network applications (electricity storage from wind turbines or solar cells for example). Many works concern the search for cathodes with high-energy density but only few studies focus their research on the synthesis of new dipolar aprotic organic solvents for LiBs electrolytes. Thus, there is a need to deviate from traditional approaches for identifying new electrolytes stable to high voltage that are based on "Trial and Errors" approaches. To alleviate this issue, a collaborative project funded by the French Research Agency (ANR) and reuniting multidisciplinary research groups that combines highly and specific complementary skills in organic chemistry, electrochemistry, solution chemistry, thermodynamics and theoretical chemistry was launched in October 2014. The present paper aims at presenting recent advances from this group on the design of new electrolytes for high-voltage batteries.
After a brief critical review of literature data about physicochemical and electrochemical properties of electrolytes for lithium-ion batteries in order to highlight the lack of homogeneity, new data will present data in order to get a homogenized database for performing QSPR calculations. In particular, this database will include a set of 20 new dipolar aprotic organic solvents synthesized and characterized in the present work. Based on the trend between the chemical structure of solvents and their physicochemical and electrochemical properties deduces from the above-mentioned database, the formulation of new electrolytes for 5V lithium-ion batteries will be presented. A particular attention will be paid on the anodic stability of these electrolytes at a NMC electrode and their behavior at a graphite electrode.
Numerical Study of Striped Diffusion during Lithiation of Tin Oxide Anodes
Authors: Ramasubramanian Ajaykrishna , Yurkiv Vitaliy , Najafi Ali , Nie Anmin , Khounsary Ali , Shahbazian-Yassar Reza , Mashayek Farzad 
Published: February 2020

Tin oxide (SnO2) is widely recognized as a promising negative electrode material for high capacity lithium (Li)-ion batteries due to its high-energy density. Recent experiments1–3 using high-resolution Transmission Electron Microscopy (TEM) show that the lithiation process in SnO2 nanowires occurs in two stages. Initially, rapid Li diffusion occurs from one end of the nanowire to the other through narrow stripes along the electrode. This stage is followed by a second stage where Li diffuses through the bulk at a much lower speed throughout the electrode leading to amorphization. In order to understand this complex phenomenon we have employed a finite element (FE) modeling in conjunction with previous in-situ TEM experiments3 to study the lithiation of SnO2 nanoelectrodes. In the experimental work, SnO2 nanowire lithiation process was characterized using in-situ TEM where the SnO2 nanowire was placed on the negative side of the in-situ setup and was brought in direct contact with the Li source.1

The idea behind FE in this context is to formulate the lithiation process using physical models which provide results consistent with experimental observations. The model is based on the understanding that in SnO2 nanowire a slip plane is created due to non-perfect contact of the source or defects and the stress at the slip planes leads to significantly higher diffusion coefficient.1

The developed constitutive model which has been implemented in FE, captures the formation of striped diffusion regime and corresponding electrode’s expansion during the lithiation of SnO2. In particular, the model incorporates the formation of stripes by using a variable nonlinear diffusivity coefficient which is a function of the concentration-dependent stress. The structural changes associated with the Li diffusion/intercalation in the electrode geometry are modeled using a 2D plane strain assumption and linear elastic material. The results from the model show a clear formation of striped diffusion regime due to the induced stresses, at low concentrations of Li. This results in a small strain of 10% within the nanowire and is followed by a bulk diffusion and expansion at higher concentrations. Thus, the simulations allow for the spatiotemporally resolved prediction and analysis of Li diffusion/intercalation and its influence on the electrode performance under the realistic operation conditions.

References

1. A. Nie, L. Y. Gan, Y. Cheng, H. Asayesh-Ardakani, Q. Li, C. Dong, R. Tao, F. Mashayek, H. T. Wang, U. Schwingenschlgl, R. F. Klie, and R. S. Yassar, ACS Nano, 7, 6203–6211 (2013).
2. L. Q. Zhang, X. H. Liu, Y. C. Perng, J. Cho, J. P. Chang, S. X. Mao, Z. Z. Ye, and J. Y. Huang, Micron, 43, 1127–1133 (2012).
3. J. Y. Huang, L. Zhong, C. M. Wang, J. P. Sullivan, W. Xu, L. Q. Zhang, S. X. Mao, N. S. Hudak, X. H. Liu, A. Subramanian, H. Fan, L. Qi, A. Kushima, and J. Li, 330, 1515 LP – 1520 (2010).
PEDOT/PSS-Coated Porous Silicon as anode of lithium-Ion Batteries
Authors: Wang Yadong , Zhang Yue 
Published: February 2020

Silicon (Si) has been regarded as the most promising anode material of lithium-ion batteries (LIBs) because of its super-high theoretical capacity. However, dramatic volume variations during cycling of lithiation/de-lithiation will trigger electrode pulverization, disruption and structural failure of solid electrolyte interface (SEI), and the according poor cycling performance as well.
Nanolization, composite with buffer material and special microstructure design of silicon based materialsare the most common strategy to alleviate the volume change effects[1-2]. The given electrode material design are usually with high-cost, complicated process and low volume specific capacity.
In this work, the porous Si in the size of several micrometers are synthesized by Metal-assisted chemical etching(MaCE) method, in which micro-sized Si particles is locally etched in the isopropyl alcohol solution containing AgNO3 and HF[3]. The resulting porous Si is subsequently coated with a thin PEDOT/PSS layer. PSS is used in dispersing porous Si particles well into an aqueous solution and then tethering EDOT monomer onto the surface of porous Si particles to facilitate the formation of a uniform PEDOT coating [4].
Fig. 1. SEM image of porous Si (a) and porous Si@PEDOT/PSS(b).
Figure 1 shows that the pore size in the as synthesized silicon particles is below 200nm, and the PEDOT/PSS is uniformed coated on the silicon particle surface. This unique micron sized core-shell structure is considered to contribute to cycle stability and rate capability. The micron size silicon particles will help the realization of favorable volume specific capacity. The suitable sized pores in the silicon will be enough to accommodate the volume change resulting from lithiation. And the PEDOT/PSS coating is used to shield the silicon from the direct contact to electrolyte and inhabit the repeated rupture and reconstruction of SEI during volume change charge/discharge cycling. The detailed electrochemical performance of this silicon electrode material will be reported in meeting poster session.
Acknowledgement Financial support by the National Science Foundation of China (21473128 and 21373154) is gratefully acknowledged.

References
[1] J. Zhang, C. Zhang, et al., Nanoscale Res. Lett.10 (2015)395.
[2] B. Wang, X. Li, et al.,Nano Lett. 13 (2013) 5578.
[3] Chang C, Liu Y, Chen C. Surface and Coatings Technology, 303, 232, 2016.
[4] Chen L, Yuan C, Dou H, et al. Electrochim. Acta, 54, 2335(2009).

Figure 1
Analysis of the Synergic Effects in LiFePO4/Li2CuO2 Cathode Blends for Li Ion Batteries Via Electrochemical and EPR Experiments
Authors: Juarez-Yescas Carlos , Guzmán Gregorio , Ramos-Sánchez Guadalupe , Aguilar-Eseiza Noe , Ramirez-Rosales Daniel , González I. 
Published: February 2020

Much of the focus in improving the specific energy in Li-ion batteries is centered on the cathode, specifically designing new active materials; moreover, a promising alternative is the use of ‘blended’ electrodes, which are comprised of at least two different active materials working synergically. Although the principle behind these collaborative properties is not yet fully understood, the reasoning behind this proposal is based on the correlation of property-function of each component. Blending two or more cathode materials can result in a cathode with fewer of the drawbacks than the parent materials, allowing for an optimized performance compared to what would be possible with the individual materials. LiFePO4 and LiCoO2 are two of the most commercial cathode materials because of their high stability and adequate specific capacities, but are unable to meet the higher capacity demands of newer technologies. Li2CuO2 is a promising cathode material with a specific capacity of 490 mAh/g, notwithstanding it undergoes irreversible phase changes during cycling, resulting in poor cyclability and a specific capacity far lower than its theoretical capacity1. The objective of this study is to take advantage of the stability of commercial active materials, such as LiFePO4 and LiCoO2 to stabilize the high capacity Li2CuO2 phase for practical use. Preliminary results of the Li2CuO2/LiFePO4 blends have shown an improved capacity, albeit still below the theoretical capacity of Li2CuO2, and a slight improvement with respect to the cyclability. The method used to blend these materials as well as the inclusion of the conductive and binding additives and the order of addition during the blending have all shown to affect the battery’s performance. Electron Paramagnetic Resonance (EPR) experiments have shown that electrodes blended with a ball mill presumably lead to the formation of stable oxygen vacancies which have an effect on the synergy which is not observable in pure Li2CuO2 blended cathodes or physical mixtures. Additionally, the presence of the conductive and binding additives during the blending process appear to result in a more homogenous mixture, preventing the reversion of Li2CuO2 into its precursors during the blending process, thus promoting higher specific capacities. The authors thank CONACyT-SENER- 416 Sustentabilidad No. 245754 for the financial support.
1. G. Ramos-Sanchez et al., Solid State Ionics, 303, 89–96 (2017).
Understanding the Solution Chemistry of Coprecipitation and the Homogeneity of the Precipitated Particle to Achieve Excellent Electrochemical Performance of Transition Metal Oxide Cathode Materials for Lithium-Ion Batteries
Authors: Dong Hongxu , Koenig Gary , Wang Anny , Barron Alexandra 
Published: February 2020

Coprecipitation is a widely used method to synthesize multicomponent transition metal cathode materials for lithium-ion batteries. The major advantages of the coprecipitation method are the homogeneity of different transition metal ions within the precipitated particles, and the tunability of the particle morphology through control of the reaction conditions. In this poster, we will show our recent results related to the coprecipitation of precursors for lithium-ion active materials, as well as their conversion to cathode materials. Solution chemistry was chosen to achieve explicit control over particle composition, and a variety of characterization methods including electrochemical evaluation were utilized to demonstrate the structure and performance of the synthesized materials. As an example material, we will use high voltage spinel LiMn1.5Ni0.5O4 synthesized from manganese and nickel blend oxalate precursor. We will present insights into nucleation and particle growth processes during particle formation in the coprecipitation reaction. We will also demonstrate the level of homogeneity that coprecipitation is able to achieve relative to traditional solid-state methods.
Stabilizing High-Voltage and High-Capacity Cathode-Electrolyte Interface Using Functional Electrolyte Component
Authors: Lee Hee-Yeol , Pham Hieu Quang , Kwon Young-Gil , Hwang Eui-Hyung , Song Seung-Wan 
Published: February 2020

Li- and Mn-rich xLi2MnO3
∙(1−x)LiMO2 (M = Mn, Ni, Co) layered oxides cathode materials are known to exhibit high specific capacities ≥ 250 mAhg−1 on the high-voltage operation above 4.6 V vs. Li/Li+,1,2 which are considered as promising cathode materials for achieving advanced high-energy density lithium-ion batteries. The capacity of these cathode materials can increase by increasing the charge cut-off voltage. However, the limited anodic instability of the conventional carbonate-based organic electrolytes above 4.2 V vs. Li/Li+ makes the attainment of high capacity from Li-rich layered oxide cathode material difficult. In order to mitigate the electrolyte issue, we have been developing new functional electrolyte components with high anodic stability above 4.6 V to stabilize high-voltage interface between Li-rich layered oxide cathode and electrolyte.1,2 High-voltage electrochemical and cathode-electrolyte interfacial studies and their correlation to high-voltage cycling performance would be presented in the meeting.

Acknowledgements

This research was supported by Ministry of Trade, Industry & Energy (R0004645) and Creative Human Resource Development Consortium for Fusion Technology of Functional Chemical/ Bio Materials of BK Plus program by Ministry of Education of Korea.

References

1. H. Q. Pham, K.-M. Nam, E.-H. Hwang, Y.-G. Kwon, H.-M. Jung, S.-W. Song, J. Electrochem. Soc., 161, A2002 (2014).
2. H. Q. Pham, E.-H. Hwang, Y.-G. Kwon, S.-W. Song, J. Power Sources, 323, 220, (2016).
Recovering Lost Capacity of Aged LiMn2O4 from Commercial Aqueous Battery By Direct Relithiation through Hydrothermal Treatment
Authors: Wang Han , Whitacre Jay 
Published: February 2020

So far, most industrial Li-ion battery recycling processes are conducted using the following two methods: hydrometallurgical method and pyrometallurgical method that completely decompose the electrodes to elemental constituents. Although improvements in term of product quality and process complexity have been made over the industrial Li-ion battery recycling processes, they are still considered to be process-intensive and energy-consuming, while also wasting the initial energy embodied during the production of the cathode materials system. 1-2

In this work, we demonstrate a novel approach to recycle LiMn2O4 as used in aqueous electrolyte batteries. LiMn2O4 cathode material was extracted from commercial aqueous battery that was cycled over several thousand cycles.3 The aged LiMn2O4 cathode material showed lower specific capacity than its uncycled counterpart. The material was then recycled by reacting it with a lithium source through two different methods: (a) solid-state reaction and (b) hydrothermal reaction. We recycled LiMn2O4 cathode material by directly relithiating the aged LiMn2O4 with a lithium source and without breaking it down into elemental form and re-synthesizing it. The advantages of this method are three folds: (1) it reduces usage of high temperature process to break down cathode materials into element form or other compound, (2) it decreases complexity of chemical process, and (3) it reduces usage of different chemicals for element refinement. This study shows the feasibility of recycling aged LiMn2O4through a simple and energy-efficient approach and recovering its lost capacity.
The outcomes of the using these two recycling methods are compared in term of phase purity, morphology, and electrochemical capacity. Our results show that the hydrothermally recycled product had superior phase purity and electrochemical capacity, and compared favorably even with uncycled material
The effect of process parameters in the hydrothermal process such as molar ratio of reactants, reaction temperature and reaction time is discussed and rated. The results show that by adjusting these process parameters, we are able to regenerate aged LiMn2O4through a simple hydrothermal reaction.

Reference:

1. Xu, J.; Thomas, H. R.; Francis, R. W.; Lum, K. R.; Wang, J.; Liang, B., A review of processes and technologies for the recycling of lithium-ion secondary batteries. J Power Sources
2008,
177(2), 512-527.
2. Georgi-Maschler, T.; Friedrich, B.; Weyhe, R.; Heegn, H.; Rutz, M., Development of a recycling process for Li-ion batteries. J Power Sources
2012,
207, 173-182.
3. Whitacre, J. F.; Shanbhag, S.; Mohamed, A.; Polonsky, A.; Carlisle, K.; Gulakowski, J.; Wu, W.; Smith, C.; Cooney, L.; Blackwood, D.; Dandrea, J. C.; Truchot, C., A Polyionic, Large-Format Energy Storage Device Using an Aqueous Electrolyte and Thick-Format Composite NaTi2(PO4)(3)/Activated Carbon Negative Electrodes (vol 3, pg 20, 2015). Energy Technol-Ger
2015,
3 (8), 796-798.

Figure 1
Single-Frequency Battery State-of-Health Diagnostic for LiFePO4 Cells in 4P1S Array
Authors: Huhman Brett 
Published: February 2020

The determination of the state of health of a battery cell is of critical importance when high discharge rates are necessary (>10C). The US Naval Research Laboratory (NRL) has performed work previously to determine a single frequency using Electrochemical Impedance Spectroscopy (EIS) that can describe the state of health for a single LiFePO4 cell. However, a battery system that can be used in the field requires multiple cells in parallel. Thus, NRL has expanded the previous work to evaluate four cells connected in parallel. The first array was constructed of cells carefully selected for the same equivalent series resistance (ESR) at 1 kHz, the same capacity to within 25 mAH, and nearly identical EIS spectra from 1 kHz – 1 Hz. Four replicant arrays were subsequently constructed of cells with identical ESR and capacity to represent the battery pack construction by a manufacturer. Each array will be pulse discharged at 10C (26 A) using a discharge profile identical to a pulsed power system at NRL. Results from the lifetime testing will be presented, with an electrochemical model and a post-mortem analysis of the battery film surfaces.
The Influence of Surface Morphology of Copper Foils on the Efficiency of Lithium Ion Batteries
Authors: Yen Chih-Han , Dow Wei-Ping 
Published: February 2020

For the increasing demand of portable electronic devices and electric vehicles, lithium-ion batteries (LIBs) become a fast-growing and crucial technology because of high power density and light weight. To manufacture LIBs with good performance and appropriate cost, the components constituting LIBs should not only possess excellent quality and reliability but also be cost-effective. The current collector in the negative electrode of LIBs is an indispensable material, and the most commonly used material is copper foil with optimal quality. Currently, the mainstream copper foil adopted in LIBs is manufactured by rolling, since the rolled copper foil provides smooth surfaces on double sides (Rz < 1 μm), which ensure good capacity retention rate. However, the rolled copper foil is much more expensive than electrodeposited (ED) copper foil, especially for ultra-thin one (< 8 μm), since it requires more times of rolling and annealing. Consequently, the manufacture of thin ED copper foil with optimal properties is a critical issue to lower the cost of LIBs. Unfortunately, the ED copper foil produced by conventional method is not applicable in LIBs industry, and the main reason is that the surface roughness of the ED copper foil on both sides is remarkably different, which affects the capacity retention rate of LIBs [1]. In addition, the actual mechanism of how the surface morphology influencing the performance of LIBs has been not studied yet. In this work, we produced an 8 μm thick ED copper foil with different surface morphology by adding specific additives in the plating bath, including very low profile copper foil (Rz < 0.1 μm) or copper foil with pinholes on the surface, and comparing the performance of these ED copper foils with a conventional ED copper foil and a commercial rolled copper foil. The surface morphology and structure of each copper foil was examined by SEM, AFM, and XRD. Most importantly, carbon based material would be coated on these copper foils and then sealed in coin cells to examine the electrochemical behavior and efficiency of lithium ion coin cells. Accordingly, the relationship of the active carbon material and the surface morphology of the negative current collector was clarified.

Reference

:

1. Kazuo Kondo, Rohan N. Akolkar, Dale P. Barkey, Masayuki Yokoi, Copper Electrodeposition for Nanofabrication of Electronics Devices, p. 243, Springer-Verlag New York (2014).
(Invited) Interface Engineering and Characterization in Lithium-Garnet Batteries
Authors: Hu Liangbing 
Published: February 2020

Solid state electrolytes are known for non-flammability, dendrite blocking, and stability over large potential windows. Garnet-based solid-state electrolytes have attracted much attention for their high ionic conductivities and stability with lithium metal anodes. However, high interface resistance with lithium anodes hinders their application to lithium metal batteries. In this talk, I will discuss various interface engineering materials for Li metal and Garnet, including ALD Al2O3, PECVD Si, metals and alloys (Nature Materials 2016; JACS 2016; Advanced Materials 2017; Science Advances 2017).
I will also discuss our recent progress on cathode-garnet interface engineering. I will also discuss our recent achievement on in-situ neutron depth profiling technique in understanding Li-garnet and CNT-garnet interfaces.