bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Carbon-Free RuO2-TiO2 Electrode for Li-Air Batteries
Authors: Park Jin-Bum , Belharouak Ilias , Lee Yun Jung , Sun Yang-Kook 
Published: February 2020

Li-O2 batteries offer the highest energy density among rechargeable batteries. This superb energy density makes the system one of the most attractive energy storage devices for electric vehicles (EV), energy storage systems (ESS), and other applications1 where high energy density is the most important figure of merit. There remain many challenges, however, for the practical application of Li-O2 batteries including low energy efficiency caused by the large energy loss during Li-O2 electrochemical cycles. The widely-accepted theoretical reaction of Li-O2 batteries is 2Li+ + O2 + 2e- ↔ Li2O2. The forward direction forming Li2O2 represents the discharge process and the reverse reaction of Li2O2 decomposition the charge process; however, many parasitic reactions have been reported, especially involving electrolyte and carbon materials.2 These undesired side reactions significantly reduce the round-trip efficiency of Li-O2 batteries. Carbon in particular, the most common material for air electrodes because of its high surface area and good electrical conductivity, may react to Li2CO3 in Li-O2 cells that impede the reversible Li-O2 reaction.2
Some of the alternative cathode materials suggested recently include TiC,3 indium tin oxide (ITO).4 Bruce and his co-workers3 ascribed the stability of TiC cathodes to the surface TiO2 layer on TiC. The TiO2 surface layer was stable from the attack of oxygen radicals during cycling. Recently, TiO2 nano tubes have been explored as a support for electrocatalysts.5 The resulting cells showed enhanced cycle life due to the higher stability of TiO2 when compared with carbon materials. The Pt or RuO2 catalyst-loaded TiO2 nanotube exhibited an enhanced cyclability with low charge potentials, especially under high current density. Despite the high specific capacity in their research, however, the actual capacity of Li-O2 batteries was not sufficient for practical application, since the specific capacity was calculated based on the catalyst loading mass, which is only 0.1 mg on a 15 mm support. Li-O2 batteries must be highly reversible with a high cell capacity for high energy applications.
Here, we synthesized RuO2/mesoporous TiO2 composites, abbreviated as RuO2/mTiO2, and used as a cathode material for Li-O2 batteries. A carbon-free electrode of RuO2/mTiO2 showed 4 mAh of cell capacity with alow charge potential of under 4 V.

References

1. J. Lu, L. Li, J.-B. Park, Y.-K. Sun, F. Wu, K. Amine, Chem. Rev. 114, 2014, 5611-5640.
2. B. D. McCloskey, A. Speidel, R. Scheffler, D. C. Miller, V. Viswanathan, J. S. Hummelshøj, J. K. Nørskov, A. C. Luntz, J. Phys. Chem. Lett. 3, 2012, 997-1001.
3. M. M. Ottakam Thotiyl, S. A. Freunberger, Z. Peng, Y. Chen, Z. Liu, P. G. Bruce, Nat. Mater. 12, 2013, 1050-1056.
4. F. Li, D. M. Tang, Y. Chen, D. Golberg, H. Kitaura, T. Zhang, A. Yamada, H. Zhou, Nano Lett. 13, 2013, 4702-4707..
5. G. Zhao, F. Mo, B. Wang, L. Zhang, K. Sun, Chem. Mater. 2014, 26, 2551-2556.
Polymer Encapsulated Sulfur Nano-Composite for Long Cycle-Life Lithium Sulfur Battery
Authors: Ansari Younes , Zhang Sonia , Chiang Yet-Ming 
Published: February 2020

The lithium-sulfur (LiS) battery is of great interest owing to its remarkable theoretical capacity of 1672 mAh g-1 and specific energy of 2600 Wh kg-1. The low operating voltage of the LiS battery (~2.0 V) provides safety advantages over high-voltage cathode materials, and elemental sulfur is environmentally friendly and inexpensive. However, well-known issues in Li-S batteries include the loss of electrical contact, low electronic conductivity of sulfur, and shuttling of polysulfides during cycling. The shuttle effect is known to cause the low utilization of the sulfur, degradation of cycle-life and, low Coulombic efficiency in LiS batteries.
Using conductive materials to encapsulate sulfur nano-particles to improve the electronic conductivity of sulfur and limit the polysulfide dissolution is one of the striking strategies for the development of LiS batteries of long cycle-life and high Coulombic efficiency (above 95%). Most polymer-encapsulated nanocomposites reported thus far require low-temperature treatment as well as long synthesis time, and have short cycle life barely exceeding 100 charge/discharge cycles. Here, we demonstrate that by controlling the pore size of the encapsulating polymer membrane, we can achieve significant improvement in the cyclability and Coulombic efficiency of an Li-S battery. Polyaniline is used as the encapsulating polymer membrane since it reacts with sulfur at high temperature to form a cross-linked structure, which is known to significantly improve the cycling performance. Morphology of the polymer may be controlled by intercalation of metal oxide nano-particles (e.g., MnO2, ZrO2, TiO2) into the pores of the porous polyaniline (PAN) as the encapsulating polymer. To accommodate the large volumetric expansion of sulfur during lithiation, sufficient empty space can be provided by heat treatment of the sulfur/PAN nano-composite.
Up until now, the sulfur/PAN nano-composites production has required low- temperature treatment of reactants for 24-48 hours under nitrogen or argon atmosphere. As a unique advantage, we provide a simplified short-time (3 hours) synthesis method at room temperature under air atmosphere.

Acknowledgment: This work is supported as part of the Joint Center for Energy Storage Research (JCESR), an Energy Innovation Hub funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences.
Intermediate Temperature Molten Salt Lithium Batteries, New Chemistries and Beyond
Authors: Giordani Vincent , Chase Gregory V , Uddin Jasim , Tan Hongjin , Tozier Dylan , Burke Colin M , Greer Julia R , McCloskey Bryan D , Addison Dan 
Published: February 2020

A current focus in battery research, particularly for electric vehicles and stationary energy storage applications, is identifying new chemistries that could enable a higher energy density and lower cost battery than currently available Li-ion batteries. Li-ion electrode materials, which dictate attainable battery energy densities, used in these batteries have changed little in the past decades, and therefore physical limits in Li-ion battery pack energy density are being approached given the enormous development efforts in the field. In this work, we take a close look at molten salt lithium batteries and in particular alkali metal nitrate/nitrite molten salt electrolytes which exhibit low melting point temperature, high ionic conductivity, high thermal stability and good interfacial properties against lithium metal anode. More specifically, we investigated the O2 electrode electrochemical behavior as well as the reduction of nitrates on metal and metal oxide nanoparticles to form lithium oxide and nitrites. The results reported herein provide a potentially transformative approach to enable a rechargeable Li-O2 battery chemistry through the use of inorganic molten salts as electrolytes. Building on our previous foundational research, in which we identified that all organic electrolytes are incompatible with the reversible Li-O2 electrochemistry, the electrolyte compositions reported here do not contain unstable organic solvents. As a result, the reversibility of the Li-O2 electrochemistry reported here is unprecedented. Another approach developed at Liox Power, Inc. is the use of nitrates as electroactive material, or in other words, as both the electrolyte and the cathode material. In this case the battery discharge reaction proceeds as the electrochemical reduction of nitrate anions NO3
- present in the electrolyte phase. High Li+ and NO3
-concentration and ionic conductivity allow extremely fast kinetics at 150 °C resulting in very low discharge overpotentials. Furthermore, we demonstrate that such electrochemical reaction is reversible and lithium oxide particles (octahedron equilibrium Wulff shape) can be recharged with energy efficiencies greater than 97%.

Figure 1. Top, voltage profile (first 2 cycles) of a cell employing a Li metal anode, a LiNO3-KNO3 eutectic and a Ni cathode, cycling at 150 °C at 0.32 mA/cm2, under Ar gas. Bottom, voltage profiles of (black) organic electrolyte Li-O2 cell and (red) LiNO3-KNO3 molten salt Li-O2 cell; both cells used a Li metal anode, a Super P carbon black cathode (5% PTFE binder) and cycled at 0.32 mA/cm2 under pure O2 gas.

Figure 1
High Rate Performance Spinel-Layered Based Li-Rich Compounds As Cathode Materials for Next Generation Lithium-Ion Batteries Application
Authors: M Subramaniyam Chandrasekar , Tai Zhixin , Liu Hua Kun , Dou Shi Xue 
Published: February 2020

A quest to hunt for reliable, cost-effective and high rate performing materials constitute the hot topic in applications for lithium-ion batteries (LiBs) in hybrid/plug-in electric vehicles. In order to foresee these objectives, herein, we have attempted to synthesis spinel-layered Li-rich Li-Mn-M-O based compound as cathode material for lithium-ion batteries applications via simple, low temperature - solvothermal method. Both as-obtained and annealed samples were characterized for their phase, morphology using x-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM), respectively. When electrochemically tested against Li+/Li0 between 2.0 – 4.8V, the annealed Li-rich spinel-layered exhibited excellent specific capacity and rate capability even at high current density, making it as a probable next generation cathode material for LiBs application.
Effects of the Chemical Structure of Thickening Agent on the Dispersion and Electrochemistry of Li-Ion Batteries
Authors: Li Chia-Chen , Chen Meng-Fu , Rohan Rupesh , Lee Jyh-Tsung 
Published: February 2020

To make electrode sheets for lithium-ion (Li-ion) cathodes or anodes with appropriate mechanical properties, the electrode-active material and conductive agent generally have to be blended with specific polymeric binders. To mix all the inorganic electrode materials homogeneously with polymeric binder, appropriate solvent that can dissolve the binder is required. According to the type of solvent used, the as-prepared electrode slurry can be classified as two systems – a water-based system and an organic solvent-based system. For environmental consistency and cost considerations, the water-based system, which uses environmentally benign binders and solvents, has attracted increasing attention and has become a new trend in the manufacture of Li-ion electrodes. Among water-compatible polymers, the aqueous emulsion of styrene-butadiene rubber (SBR) is the commonly used binder for electrodes of Li-ion batteries. It is known that SBR provides not only good binding for electrode powders but also the required adhesion of electrode sheets to the current collector. Nevertheless, SBR comes in the form of an aqueous emulsion, which has very low viscosity and, therefore, does not facilitate the wetting of its fabricated electrode slurry on the current collector during casting. To improve the wetting, SBR is generally blended with the thickening agent CMC.
Many studies have shown that using CMC as a thickening agent is beneficial to the rate capability of the as-prepared cathodes but too much addition may cause the corresponding electrode slurries to gel, which the gelled slurries are unavailable for casting. Since CMC contains two kinds of functional groups, carboxyl and hydroxyl groups, it would be interesting to clarify which one of the functional groups causes the gelation of the electrode slurries. Based on the experimental results of replacing CMC by other reagent, such as poly(vinyl alcohol) (PVA), poly(acrylic acid) (PAA) and guar gum (GG), it was found that the hydroxyl group rather than the carboxyl group dominates the gelation of CMC in the slurry. Besides to the gelling function, the presence of hydroxyl group in the chemical structure of the thickening agent is also detrimental to the electrochemical performances of as-constructed electrodes and Li-ion cells.
Electrochemical Behavior of Li5FeO4 (LFO) in Energy Storage Applications
Authors: Johnson Christopher , Lin Chi-Kai , Lee Eungje , Su Xin , Lu Wenquan , Trask Stephen E. , Wang Xiaoping , Maroni Victor A. , Ren Yang , Alp Esen E. , Brown Dennis , Krumpelt Michael , Thackeray Michael M. , Chan Maria K. Y. , Kinaci Alper , Li Liang , Yao Zhenpeng , Wolverton Christopher 
Published: February 2020

The push for high capacity cathodes capable of Li storage greater than Li/TM (TM=transition metal) ratio of one in Li-ion batteries (LIB) is extremely challenging, but necessary to increase energy densities. The rock-salt layered lithium oxide material, Li2MnO3, is particularly well studied and can release essentially all of its Li during electrochemical charge on the first cycle yielding over 400 mAh/g (cycled >4.6 V vs. Li metal), but this process is irreversible, and capacity rapidly fades. Recently we have been studying the electrochemical behavior of higher lithium-content containing phase, Li5FeO4 (LFO) (a defect anti-fluorite structure, with large lithium content, Li/Fe = 5), in the following three roles: (1) as a reversible 2.8 to 3.0 V cathode, (2) as a Li-source additive to enable Si anode for LIBs, and (3) as a hybrid Li-ion•Li-O2 cathode material.1 As reported by our group, this LFO can provide over 700 mAh/g specific capacity below 4.4 V vs. Li metal2 which now identifies it as an ideal candidate for a myriad of energy storage applications. This poster highlights the LFO material and addresses the following aspects: (1) synthesis of LFO, (2) electrode fabrication, blends and implementation in LIB full cells. The LFO is particularly effective at full cell cycle improvement due to both elimination of high first cycle irreversible capacity losses (ICL), and cycle-to-cycle inefficiencies. Lastly we will back-up our findings through a number of characterization methods in addition to first principles modeling. For example we make use of
novel fast operando Mössbauer spectroscopy
in order to decipher the charge compensation and the stability of tetravalent iron (Fe4+) during real-time cycling of Li/LFO pouch cells. All these results taken together have given us ample understanding of the material, its versatility and extreme effectiveness in energy storage.
[1] L. Trahey, et al., Electrochem. and Solid State Lett., 14, A64 (2011)
[2] C. S. Johnson, et al., Chemistry of Materials, 22, 1263-1270 (2010)

This work was supported as part of the Center for Electrochemical Energy Science (CEES), an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences. Use of the Center for Nanoscale Materials, (Raman) The Advanced Photon Source (operando XRD), and the Electron Microscopy Center (SEM) is supported by the U. S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.
A Systematic Adhesion Map in Lithium-Ion Battery Electrodes Having Different Design Parameters By Using a Saicas Tool
Authors: Kim Kyuman , Byun Seoungwoo , Cho Inseong , Ryou Myung-Hyun , Lee Yong Min 
Published: February 2020

When we fabricate a variety of electrodes for lithium-ion batteries (LIBs), some electrode design parameters such as composition, loading level, density, etc. are generally predetermined depending on the targeted energy and power densities. Since they are complexly related to each other, repetitive experiments should be carried out to get reliable long-term cycle life as well as initial capacity. At this point, an optimum binder content or density always remains a difficult question, because there is no systematic research on adhesion properties for LIB electrodes. In addition, only the peel test with the 3M Scotch tape has widely used to compare electrode adhesion strength as a relatively comparing tool. Thus, our group has introduced a tool, the Surface and Interfacial Cutting and Analysis System (SAICAS), to measure shear stress as well as adhesion strength of the LIB electrodes [1-3]. Although our previous works provided battery scientists and engineers with worthwhile data, more systematic investigation to separate intrinsic adhesion property from loading is greatly required.
Herein, we applied the SAICAS tool to measure all the adhesion properties of LIB LiCoO2 electrode having three different loading levels, 5, 10, and 15 mg cm-2, and four different electrode densities, 2.0, 2.5, 3.0, and 3.5 g cm-3. Not only the adhesion strength between current collector and electrode coating layer, but also the adhesion strength at the middle of the electrode coating layer are obtained and compared to divide each intrinsic adhesion strength independent of loading effect. From those data, we could propose an empirical equation to predict adhesion strength if density and loading level are provided. This equation is also confirmed in the LiCoO2 electrode system by comparing the adhesion strength of arbitrary electrodes with different loading and density.

Acknowledgements

This work was supported by the Human Resource Training Program for Regional Innovation and Creativity through the Ministry of Education and National Research Foundation of Korea (NRF-2014H1C1A1066977).

References

[1] Son, B.; Ryou, M.-H.; Choi, J.; Lee, T.; Yu, H. K.; Kim, J. H.; Lee, Y. M., Measurement and Analysis of Adhesion Property of Lithium-Ion Battery Electrodes with SAICAS. ACS Appl. Mater. Interfaces 2013, 6, 526-531.
[2] Choi, J.; Ryou, M.-H.; Son, B.; Song, J.; Park, J.-K.; Cho, K. Y.; Lee, Y. M., Improved High Temperature Performance of Lithium-Ion Batteries through Use of a Thermally Stable Co-Polyimide-Based Cathode Binder. J. Power Soures 2014, 252, 138-143.
[3] Choi, J.; Kim, K.; Jeong, J; Cho, K. Y.; Ryou, M.-H.; Lee, Y. M., Highly Adhesive and Soluble Co-polyimide Binder: Improving the Long-Term Cycle Life of Silicon Anodes in Lithium-Ion Batteries, ACS Appl. Mater. Interfaces, 2015, 7, 14851-14858

Figure 1
A Single-Lithiun-Ion Conductor Coordinated Porous Pvfm-Peg Based Membrane and Plasticizer As Electrolyte for Lithium Ion Batteries
Authors: Lian Fang , SUN Xiaomeng 
Published: February 2020

Polymer electrolyte comprised of lithium dissolved in polymer matrix has draw great attention due to its safety as well as processability, flexibility and lightweight. The dissociation of binary lithium salt in polar polymer matrix gives rise to so called bi-ionic conductors in which both cations and anions migrate as charge carriers. But unfortunatelly, a serious concentration polarization takes place in bi-ionic conductors due to the buildup of the anions at the electrode/electrolyte interface[1]. In order to solve the above problem, a single ion conductive polymer electrolyte has been proposed, in which the counter anions are tethered to the polymer backbone or immobilized in a matrix, eliminating polarization loss and enabling the passage of larger currents through the cells[2]. Until recently, single ion polymer electrolytes reported show low ambient temperature ionic conductivities (<10-6S·cm-1) due to the strong interaction between cations and their immobile matrixes[3].
A single-ion conductive hybrid electrolyte of porous PVFM-PEG based membrane and the optimized PC/EC (1/1, vol) mixed solvent as plasticizer was fabricated. The membrane and its electrolyte were characterized using scanning electron microscopy (SEM), stress-stain test, linear sweep voltammetry (LSV), ionic conductivity and lithium ion transference number measurement. The results indicate the combination of optimized PC/EC (1/1 in vol) plasticizer and porous PVFM-PEG based membranes[4] contributes to a considerable enhancement of room-temperature conductivity to 1.59×10-4S/cm. At the same time, lithium ion transference number of hybrid electrolyte based on the porous PVFM-PEG electrolyte membranes increased to 0.76. The assembled cells from the hybrid electrolyte also show wide electrochemical stability window and excellent cyclability.
Reference
[1] Bouchet R, Maria S, Meziane R, et al. Single-ion BAB triblock copolymers as highly efficient electrolytes for lithium-metal batteries[J]. Nature materials, 2013, 12(5): 452-457.
[2] Sinha K, Wang W, Winey K I, et al. Dynamic Patterning in PEO-Based Single Ion Conductors for Li Ion Batteries[J]. Macromolecules, 2012, 45(10): 4354-4362.
[3] Kobayashi N, Uchiyama M, Tsuchida E. Poly [lithium methacrylate-co-oligo (oxyethylene) methacrylate] as a solid electrolyte with high ionic conductivity[J]. Solid State Ionics, 1985, 17(4): 307-311.
[4] Fang Lian, Hong-yan Guan, Yan Wen, Xiao-rong Pan, Polyvinyl formal based single-ion conductor membranes as polymer electrolyte for lithium ion batteries, Journal of membrane science 2014, 469, 67-72
Materials for High Energy Density and Long-Life Lithium-Sulfur Batteries
Authors: Bugga Ratnakumar V , Jones Simon C. , Jones John-Paul , Pasalic Jasmina , Torres Loraine , Addison Dan , Thiallaiyan Ramanathan 
Published: February 2020

Lithium ion batteries have been successfull deployed in several NASA missions since 2000, including the Mars Exploration Rovers (Spirit and Opportunity), Mars Science Laboratory (MSL), Pheonix Lander, JUNO, Aquarius, Keppler Rovers and SMAP. Being compact, lightweight and durable, these batteries have contributed to significant enhancement or even enablement of these missions. However, NASA’s future missions, i.e. small planetary rovers, planter probes, small satellites, CubeSats etc., warrant more efficient battery technologies, ‘beyond Li-ion,’ with higher energy densities. The lithium-sulfur system emerges as the most promising technology because of its high theoretical specific energy (3-4x) compared to Li-ion cells. To address the needs of the future missions, NASA has initiated projects to develop high-energy and long-life lithium-sulfur cells, with a high cell specific energy of 400 Wh/kg, good cycle life of 300 cycles and an ability to operate safely over a wide temperature range of -10 to +30 °C. Despite its high theoretical energy densities and significant developmental efforts in several laboratories, Li-S technology hasn’t matured yet, mainly due to challenges related to the leaching of reduced products into the electrolyte forming a redox shuttle and also poisoning the lithium anode. Several attempts are being made in the literature to develop cathode designs, e.g., hierarchical porous carbon structures to sequester sulfur and its reduction products, and also electrolyte solutions to minimize their solubility. 1-5 In a similar manner, we have developed improved cell components for Li-S cells,6 i.e., i) new sulfur cathodes with metal sulfide blends that show high specific capacities of ≥800 mAh/g at C/3 rates with high material loadings required for achieving high specific energy and energy densities, ii) Li anode protected with suitable polymer electrolytes that display efficient Li cycling and durability in laboratory Li-S cells, and iii) Electrolytes with co-solvents electrolyte additives and iv) new proprietary electrode coatings serving as polysulfide blocking layers to inhibit the deleterious effects of sulfur redistribution and contribute to a good cycle life. In this paper, we will describe some of these material developments and their electrochemical behavior in three-electrode cells and performance in laboratory pouch.

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Ratnakumar Bugga, Simon Jones, Jasmina Pasalic, Dan Addison and Ramanathan Thillaiyan, 228th ECS Meeting, Phoenix, AZ, Oct. 11 (2015)