bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of Crosslinking of Guar Gum As a Bio-Derivative Binder for Negative Electrodes of Lithium-Ion Batteries
Authors: Choi In-Yeong , Lee Ji-Eun , Oh Eun-Suok 
Published: February 2020

Nowadays, large-sized lithium-ion batteries (LIB) for electric vehicles (EV) and energy storage systems (ESS) require extraordinary long-cycled, high-powered, and high-capacity, when compared to small-sized LIBs for mobile devices. In addition, it is also necessary to actively respond to environmental problems by applying green materials.
From our previous results, guar gum binders, branched polysaccharides, facilitated the transport of lithium ions in Li4Ti5O12(LTO) electrodes than conventional carboxymethyl cellulose (CMC) binders, linear polysaccharide, even though their adhesive strength were not as strong as CMC[1]. Unlike polyvinylidene fluoride (PVdF), guar gum binder was soluble in water, thus allowing the LIB manufacturing process to be environmentally friendly.
In this study, we investigate the effect of crosslinking of the guar gum binder on their mechanical properties in the LTO electrodes. To evaluate the effect of these crosslinking, a variety of physical and electrochemical characterization are applied.

Reference

1. Bo-Ram Lee, So-Jin Kim and Eun-Suok Oh, Journal of the Electrochemical Society, 161, A2128-A2132 (2014)
High Performance Pillared Vanadium Oxide Xerogel Cathode for Lithium Ion Batteries
Authors: Hawthorne Krista L , Tung Siu on , Mainero James , Ding Yi , Thompson Levi T 
Published: February 2020

Lithium ion batteries commonly utilize layered oxide materials as the cathode, where lithium is intercalated and deintercalated between the layers in the crystal structure during cycling. The repeated lithium insertion and extraction can cause stress on the material, leading to fracture. Additionally, the extent of lithiation may cause phase changes in the layered structure that are sometimes irreversible. These changes to the material cause capacity loss and reduce the battery cycle life. This research focuses on nanostructuring layered oxides to enhance their cyclability and power capabilities. In particular, vanadium oxide xerogels were modified by adding pillaring molecules between the layers to increase the interlayer spacing. Vanadium oxide xerogels possess attractive capacities but suffer from significant capacity fade due to distortion of the crystal structure. We hypothesize that the pillars will enhance thermal and mechanical stability by reducing the strain on the structure and increasing lithium ion mobility, thereby increasing the cycle life and high rate capacities.
Aluminum Keggin ions were used as pillaring agents for the vanadium oxide xerogels. X-ray diffraction showed an interlayer spacing increase from 1.14 to 1.32 nm after pillaring, consistent with the size of the keggin ions (~1.3 nm), while still maintaining the layered V2O5 xerogel crystalline structure (Figure 1). Elemental analysis indicated an aluminum loading of 9 wt% in the pillared material. The pillared materials also demonstrate increased thermal stability and rate capabilities during cycling in coin cells, with capacities over 60% higher than those of the unpillared V2O5 xerogel. Additionally, the pillared materials retained more capacity during cycling at C/2. Pillaring the layered vanadium oxide xerogels improved both capacity retention and battery lifetime.
Figure 1. Diffraction patterns for V2O5 xerogel (a), pillared V2O5 xerogel (b), and pillared V2O5 xerogel after heat treatment in either air (c) or nitrogen (d). The dotted line is intended as a guide for the eye.

Figure 1
Lithium Iron Phosphate Nanosheet Nests As Cathode Material for Li-Ion Batteries
Authors: Wainright Robert John , Ramasamy Ramaraja P. 
Published: February 2020

Nano Electrochemistry Laboratory, College of Engineering, The University of Georgia, Athens, GA 30602.

Lithium-ion batteries are the current state-of-the-art energy storage technology for advanced electric vehicles and portable power applications due to their high energy density. The need for low cost lithium ion batteries has driven the development of inexpensive LiFePO4 cathodes, which offer a relatively high specific capacity (170 mAh·g-1) and relatively high discharge potential plateau (3.45 V) at a fraction of the cost of other materials. In additional to the low electrical conductivity, one of the major drawbacks of this material is the inherently slow lithium diffusion. Unlike spinel or layered structures, the olivine structure of LiFePO4 allows lithium diffusion in only one direction and therefore severely limits the intercalation rate due to slow solid-state diffusion. This limitation could be overcome by de-sizing the material in the < 010 >, the direction of diffusion. This can be achieved by synthesizing LiFePO4 nanosheet nests (LFP-NSN) using a directed growth method adapted and modified from a synthesis procedure reported earlier.1 Figure 1 shows the scanning electron microscopy (SEM) image of the LFP-NSN synthesized by our modified procedure. Figure 2 shows the X-ray diffraction (XRD) pattern of the synthesized LFP-NSN, which compares well with the XRD pattern of orthorhombic, olivine-type LiFePO4 from the library. For battery testing, the synthesized structures were mixed in a ratio 80:10:10 of LFP-NSN: Super C carbon: poly(vinylidine fluoride) in N-methyl pyrrolidone to form a slurry that was cast on aluminum foil to be used as the cathode in CR2032 lithium ion coin cells for testing and evaluation.

Fig. 1: a) SEM image and b) XRD pattern (black) with LiFePO4 characteristic peaks identified in red of LFP-NSN synthesized by a solvothermal reaction.

Acknowledgements:

The authors would like to thank Dr. Tina Salguero and Dr. Zhengwei Pan for their help in this project.
* Corresponding Author: rama@uga.edu

Reference:

1. Y. Zhao, L. Peng, B. Liu and G. Yu, Single-Crystalline LiFePO4 Nanosheets for High-Rate Li-Ion Batteries. Nano letters
2014,
14, 2849-2853.

Figure 1
High Capacity Hybrid Si-SWCNT Anode Structures for Li-Ion Batteries
Authors: Bobrenok Oleg , Kosolapov Andrew , Shchukin Victor , Sharafutdinov Ravel , Predtechensky Mikhail , Tikhonov Konstantin , Notman Konstantin 
Published: February 2020

In this presentation we describe structure, synthesis routes and electrochemical performance of hybrid Si-SWCNT composites developed by our team. We have investigated several approaches to the design of the silicon anodes to accommodate volumetric changes during charge and discharge of Si active material. Mass-produced single wall carbon nanotubes (SWCNTs) were used as a structural component in the 3D electrode matrix to provide mechanical support and conductivity path to deposited Si nano-beads. In other structures, layers of SWCNT acted as a cushion accommodating volumetric changes of Si layers. Initial capacity of 2500mAh/g was achieved with good capacity retention up to 300 cycles. Advantages and shortcomings of several Si-SWCNT anode designs will be discussed.
Ternary Type I Silicon Clathrates for Lithium-Ion Battery Anodes
Authors: Li Ying , Chan Candace K. 
Published: February 2020

Silicon clathrates contain cage-like structures that can encapsulate various guest atoms or molecules. Here we present an electrochemical evaluation of type I silicon clathrates based on Ba8AlySi46-y as the anode material for lithium-ion batteries. Post-cycling characterization with NMR and XRD show no discernible structural or volume changes even after electrochemical insertion of 44 Li (~1 Li/Si) into the clathrate structure. The observed properties are in stark contrast with lithiation of other silicon anodes, which become amorphous and suffer from large volume changes. The electrochemical reactions are proposed to occur as single phase reactions at approximately 0.2 and 0.4 V vs. Li/Li+ during lithiation and delithiation, respectively, distinct from diamond cubic or amorphous silicon anodes. Reversible capacities as high as 499 mAh g-1 at a 5 mA g-1 rate were observed for silicon clathrate with composition Ba8Al8.54Si37.46, corresponding to ~1.18 Li/Si. These results show that silicon clathrates could be promising durable anodes for lithium-ion batteries. Changing the composition of the clathrate, namely replacing the Ba guest atom and Al framework substitution with other metals, was found to have a strong effect on the number of Li reversible inserted into the structure. The cycling performance of the clathrate electrodes in different liquid and solid electrolytes will also be presented.
Reference:
Y. Li, R. Raghavan, N.A. Wagner, S.K. Davidowski, L. Baggetto, R. Zhao, Q. Cheng, J.L. Yarger, G.M. Veith, C. Ellis-Terrell, M.A. Miller, K.S. Chan, C.K. Chan, Advanced Science, DOI: 0.1002/advs.201500057, (2015).
Mineral-Inspired, Nanostructured Polyanion Materials for Rechargeable Battery Electrodes
Authors: Zhao Ran , Li Ying , Chan Candace K. 
Published: February 2020

Polyanion materials are promising candidates for new rechargeable battery electrodes due to their good capacity, operation voltage, safety characteristics, as well as low cost. A family of materials based on metal hydroxysulfate or hydroxyphosphate naturally occurring minerals offers the possibility for improved performance as cathode materials due to the following characteristics: (1) open framework or layered structures that can facilitate fast Li+ insertion, (2) flexibility in alkali and transition metal cation incorporation as observed in nature, which can allow for the design of solid-solutions to enhance structural stability, capacity, and reaction potentials, and (3) possibility for multi-electron redox reactions, which can result in capacities >200 mAh/g. This presentation will introduce our investigation into nanostructured brochantite and jarosite minerals for use as electrodes in Li-ion and Na-ion batteries.
The electrochemical properties of brochantite, Cu4(OH)6SO4, a natural mineral and patina constituent on the Statue of Liberty, were investigated. Nanostructured brochantite was synthesized using precipitation and microwave-assisted hydrothermal reactions and evaluated in half-cells with Li metal counter electrodes. Reversible capacities >400 mAh/g corresponding to the 2 electron reduction of Cu2+ and discharge potential of 1.8 V versus Li/Li+ were observed in brochantite with a nanoplate morphology.
The electrochemical properties of the jarosite and V3+ jarosite analogue compounds, MN3(SO4)2(OH)6, where M=K, Na and N=Fe, V, were also investigated. A common industrial mining waste byproduct and naturally occurring mineral on Earth and Mars, the jarosite structure can accommodate many different cations and may serve as a good starting point for developing cathodes for batteries beyond Li-ion. Microstructured jarosites were synthesized using microwave-assisted hydrothermal reaction and the electrochemical characteristic were evaluated in half-cells with Li and Na metal.
Detailed characterization using X-ray diffraction, scanning and transmission electron microscopy, and X-ray photoelectron spectroscopy was performed to better understand the structural changes and reaction mechanisms in both brochantite and jarosite systems.
Reference:
R. Zhao, T. Yang, M.A. Miller, C.K. Chan, Nano Lett., 13, 6055 – 6063 (2013).
Operando high-Energy Synchrotron X-Ray Diffraction and Modeling of Alpha-MnO2 Battery Materials upon Heat Treatment
Authors: Yang Zhenzhen , Chan Maria K. Y. , Ren Yang , Johnson Christopher , Thackeray Michael M. 
Published: February 2020

Hybrid Li-ion/Lithium-O2 batteries offer extremely attractive theoretical energy densities and therefore represent a rapidly emerging area of research. Our research has focused on developing dual-functioning metal oxides electrode/electrocatalyst materials that can lower the charge hysteresis and potentially impact the nature of the discharge products. Specifically we have synthesized and characterized the transition metal oxide, α–MnO2, which has a hollandite-type structure with relatively large, one-dimensional (1-D) ‘2x2’ tunnels formed by the connection of octahedral [MnO6] units, operates as a superior electrode/catalyst in hybrid Li-ion/Li-O2 cells. α–MnO2 generally contains 2~3% of lattice water in the crystal structure, which stabilizes the structure and dramatically influences not only electrochemical properties but also other properties such as density and electronic conductivity. The water can be removed from α-MnO2 framework by heat treatment without degradation of the structure, and then partially replaced by Li2O. The Li2O-doped alpha-MnO2 electrodes, stabilize the structure and provide higher capacities on cycling than the parent material. However, the structure changes of hydrated and dehydrated MnO2 related with electrochemical properties has not been clarified yet. Herein we report operando temperature-resolved high energy X-ray diffraction experiments performed on alpha-MnO2 electrodes. The data provides evidence that the crystal structure of α-MnO2 undergoes reversible changes in lattice parameters and strain during heating and cooling. Insights into reversible changes of tunnel structure of MnO2 with H2O/H3O+, as determined by first principles density functional theory calculations, are used to provide a possible explanation for some of the observed results. With the help of the proposed technique, we are expecting to understand the water removal and insertion into MnO­2 and generate knowledge on how to improve the sustainability in the practical usage of α-MnO2 as Li and oxides capture medium for hybrid Li-ion/Li-O2 cells.
Biwedge Octahedron-Shaped Li-Excess Nickel-Manganese Oxide Cathode Showing Remarkably Suppressed Potential Fade
Authors: Wu Nae-Lih , Chen Wen-Chin , Wu Hung-Chun 
Published: February 2020

Li-ion batteries (LIBs) are foreseen to play a very important role in energy storage for the next decade. Research for advanced Li-ion secondary batteries has been following the direction toward higher energy and power densities. Various cathode materials, such as LiCoO2, LiMn0.33Ni0.33Co0.33O2, spinel LiMn2O4,olivine LiFePO4, and Li1+x(M,Mn)1-xOy, having different or similar lattice structures have been developed. Among these materials, the class of layered Li-rich Mn-transition metal oxides (Li1+x(M,Mn)1-xOy) has lately drawn escalated attention due to their potential high capacities beyond 200 mAh/g. In these oxides, the excess Li ion gives rise to the presence of inter-grown Li2MnO3 slabs within Li(M,Mn)O2 matrix to form a layered “composite” structure. These Li2MnO3 slabs may be transformed to electrochemical active MnO2 layers by removal of Li+ upon charging above 4.5 V (versus Li/Li+) and stabilizing the layered structure under high depth of lithiation/de-lithiation during the charge/discharge cycles. During charge and discharge process, the layered composite suffers from the well known phenomena of potential fade. The potential fade has been attributable to the migration of the transition metal ions, notably manganese and nickel, into the lithium layers, causing slow transformation to a spinel-like domain within the crystal lattice. The fade results in gradual loss in energy capacity of the electrode.
In this study, a biwedge octahedron-shaped Li1+x(M,Mn)1-xOy powder has been synthesized via a oxalate-based precipitation process followed by high-temperature calcination. The resulting powder shows a large aspect ratio with a width near 10 μm and a thickness of a couple of μm. The large width allows for high powder tap density, while the small thickness enables fast charging-discharging kinetics. More importantly, in either full-cell or half-cell testing, the resulting oxide electrode showed essentially no potential fade after several hundred cycles. The synthesis process and the material and electrochemical characterization results will be presented.

Figure 1
Identification of Multiple Failure Mechanisms in Si-Based Electrodes for Li-Ion Batteries
Authors: Beattie Shane D , Loveridge Melanie , Polzin Bryant J , Lain Michael J , Rubio Irene 
Published: February 2020

Identification of multiple failure mechanisms in Si-based electrodes for Li-ion batteries
Silicon (Si) electrodes are often studied as an alternative to graphite for negative electrodes in Lithium-ion (Li-ion) battery technology due to their high theoretical specific and volumetric capacity (3579 mAh/g and 2190 mAh/cm3respectively). Although encouraging theoretically, practical silicon electrodes exhibit relatively low cycle efficiency, causing capacity to drop quickly as a function of cycle number. There are numerous factors which conspire to reduce cycle life in silicon electrodes. Eight of the most important factors to consider are:
1) Evolution of the voltage profile to higher charge voltages as a function of capacity/cycle number and the effect on cycle efficiency (Figure 1)
2) Large expansion during lithiation (up to 280%)
3) Delamination from the current collector as a function of cycle number (Figure 2)
4) Instability of the Solid Electrode Interphase (SEI) due to large volume expansion
5) Instability of the electrolyte with lithiated silicon (Figure 3)
6) Excessive gassing due to electrolyte decomposition
7) Continued growth of electrode thickness as a function of cycle number
8) High porosity and therefore low volumetric energy density
This communication will present data exemplifying each of the failure mechanisms above.
In addition, the use of a Raspberry Pi to collect data for some of the experiments above will be discussed (Figure 3).

Figure 1
A New Design and Fabrication of Si-C Composite for Lithium-Ion Batteries Anodes
Authors: Ogata Ken , Takei Koichi , Lee Byoung-Sun , Lee Kang Hee , Yu Tae-Hwan , Doo Seokgwang 
Published: February 2020

For the last few decades, nano-structured silicon anodes are expected to be alternatives to graphitic carbons in rechargeable Li-ion batteries, owing to their extremely high capacities [1,2]. Despite the recent intensive studies with a variety of elaborated nano-Si materials, major use of Si in the anode, i.e. with higher Si wt% in graphite, is still limited. This is due to numerous and entangled issues, the most basic being the complex kinetics and thermodynamics that control the reactions and the huge structural rearrangements, which we have previously elucidated [3]. Based on our previous findings, in this study, we have re-designed and fabricated Si-C composites with scalable methods that can intrinsically overcome the fundamental degradation issues, correlating its electrochemical properties with Li-Si local phase transformations at atomistic scale. Details will be discussed at the conference.
[1] Obrovac, M. N. & Christensen, L, Electrochem. Solid-State Lett. 7, A93–A96 (2004).
[2] Holzapfel, M. et al., Electrochim. Acta 52, 973 (2006)
[3] Ogata, K. Grey, C.P., et al., Nat. Commun. 5, 3217 (2014)
Foldable Paper-Based Lithium-Ion Batteries
Authors: Chan Candace K. 
Published: February 2020

One of the most important aspects to enabling paper electronics are suitable and well integrated power sources. A convenient and useful aspect of paper is its ability to be folded into a multitude of shapes, such as those available by applying origami concepts, which can open the door for unprecedented types of paper electronics. Hence, the development of robust batteries that can also be folded is attractive for achieving good integration with paper-based devices. In this talk, I will discuss how paper folding techniques inspired from Japanese origami can be used to compact a Li-ion battery and increase its energy per footprint area. Full cells were prepared using Li4Ti5O12 and LiCoO2 powders deposited onto current collectors consisting of paper coated with carbon nanotubes. Folded cells showed higher areal capacities compared to the planar versions, with a 5 x 5 cell folded using the Miura-ori pattern displaying a ~14X increase in areal energy density. Furthermore, these cells could achieve extremely high levels of deformability, including foldability, bendability and twistability. This strategy represents the fusion of the art of origami, materials science, and functional energy storage devices and provides new opportunities for foldable, flexible and curvilinear electronics with new mechanical characteristics and functionalities.

References:
Q. Cheng, Z. Song, T. Ma, B.B. Smith, R. Tang, H. Yu, H. Jiang, C.K. Chan, Nano Lett., 13, 4969-4974 (2013).
Z. Song, T. Ma, R. Tang, Q. Cheng, X. Wang, D. Krishnaraju, R. Panat, C.K. Chan, H. Yu, H. Jiang, Nature Commun., 5, 3140 (2013).
Design, Fabrication and Characterization of Flexible Thin Film Rechargeable Lithium Ion Batteries
Authors: Oukassi Sami , Giroud-Garampon Cédric , Poncet Séverine , Salot Raphaël 
Published: February 2020

The advent of fully flexible electronics is considered as a major technological leap forward and has attracted much attention during the last decade. Compared with conventional electronics, flexible electronics are lightweight, bendable and may be wearable or implantable. Hence the rapid and continuous growth in this field has stimulated the research and development of corresponding flexible energy storage systems and more particularly rechargeable lithium ion batteries [1-3].
In this work we developed flexible thin film lithium ion batteries based on all-solid-state materials. The flexible batteries were fabricated using sequential physical vapor deposition techniques. A thin film battery (TFB) architecture consisting of Ti/V2O5/LiPON/Li/encapsulation multilayer was deposited on flexible polyimide substrate. The fabricated flexible TFBs presented an overall thickness of 70µm (figure 1).
The flexible TFBs delivered discharge capacity as high as 0.15mAh (1.5 cm² of cathode area) upon galvanostatic cyling at C/5 rate within 3.8-1.5V voltage range. The capacity decreased during cycling with an average fading rate of 0.25% over 100 cycles (figure 2). Electrochemical impedance spectroscopy (EIS) measurements and modeling analysis revealed a significant and continuous increase of the internal resistance during cycling. Furthermore, it was shown that the internal resistance increase was induced by a progressive decrease of the electrolyte/electrodes contact area. A strong correlation was identified between the variation of electrolyte/electrode contact area and variation of flexible TFB discharge capacity.
TFBs having the same architecture and the same design were fabricated on two substrates: a flexible polyimide foil and a rigid silicon wafer. Electrochemical characterization showed a clear influence of substrate type on TFBs discharge capacity and internal resistance variations during cycling (figure 3). The electrochemical results variation with substrate type is discussed in terms of differences of TFB multilayer mechanical behaviour during cycling in both configurations.
References
1- Y. Hu and X. Sun, J. Mater. Chem. A, 2, 10712 (2014).
2- L. Li, Z. Wu, S. Yuan, and X. Zhang, Energy Environ. Sci., 7, 2101 (2014)
3- M. Osiak, H. Geaney, E. Armstrong and C. O'Dwyer, J. Mater. Chem. A, 2, 9433 (2014).

Figure 1