bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spherical Shaped Particle of Randomly Packed LiFePO4 Nanoplates for High-Rate of Li-Ion Batteries
Authors: Oh Woong , Patil Virendra , Yoo Jong Won , Yoon Won-Sub , Yi Gi-Ra 
Published: February 2020

Energy storage is the key factor for saving and using renewable energy. Among the various energy storage devices, Li-ion battery is the most promising storage device owing to its high energy density, efficiency and cycle life. Not only for the small application like mobile phone and laptop computer but also electric vehicles (EVs) and massive energy storage system (ESS), numerous applications have been used Li-ion battery. However its high energy density is like a double-edged sword, the safety issues have been a problem for the practical market. The safety problems from the Li-ion battery usually come from thermal runaway, which is mainly come from oxygen release from the cathode material. Lithium iron phosphate (LFP) has PO4 polyanion that oxygen atom is strongly bonded with phosphorus and prevents oxygen release, therefore, it is well known as the safe cathode material for the Li-ion battery. Also for the high power battery applications, LFP is a promising material owing to the ability of high-rate charge and discharge performance. For the high rate availability on LFP material, two important key factors should be satisfied; one is fast ion diffusion inside the material and the other is high electric conductivity. The Li-ion diffusivity coefficient and electron conductivity are intrinsic properties of the material, however, particle size or morphology and conducting agent coating can raise the speed of diffusion and conduction.
Here, we demonstrated those factors by solvo-thermally synthesized plate shape nanoparticle and spherical secondary particle with carbon coating using spray-drying. The nanoparticle has a flat shape in b-axis, therefore, diffusion speed increase because the diffusion distance of lithium is greatly reduced. The nanoparticle without spray-drying showed low capacity and also poor C-rate performance even with the carbon coating. Besides, after forming the spherical particles, it showed 162mAh/g of initial capacity at the 0.1C rate and maintains more than 80% of initial capacity (~130.91mAh/g) at the 50C rate. Moreover, electrode density which is the intrinsic weakness of nanoscale electrode material has been improved and the spheres carried out excellent cycling ability which shows 98% capacity retention over 500cycles at 1C after the high C-rate test. In order to analyze the causes of such good characteristics, morphology and crystallographic directions were confirmed by SEM and TEM image, and electrical conductivity and diffusion coefficient were calculated by using Cyclic Voltammetry (CV), Galvanostatic Intermittent Titration Technique (GITT) and Electrochemical Impedance Spectroscopy (EIS).
More details will be discussed at the meeting.
(Invited) Preserving a High Energy Density of the Lithium-Rich Layered Oxides (LLO) and New Lithium Diffusion Model for Llo
Authors: Kang Kisuk 
Published: February 2020

Lithium-rich layered oxides (LLOs) are considered promising cathode materials for lithium-ion batteries because of their high reversible capacity, which is attributed to the exploitation of the novel anionic redox in addition to the conventional cationic redox process. Cobalt-free layered lithium-rich nickel manganese oxides, Li[LixNiyMn1
−
x
−
y]O2, are one of the promising positive electrode materials for lithium rechargeable batteries because of their high energy density and low materials cost. However, substantial voltage decay is inevitable upon electrochemical cycling, which makes this class of materials less practical. It has been proposed that undesirable voltage decay is linked to irreversible structural rearrangement involving irreversible oxygen loss and cation migration. In the first part of my talk, we demonstrate that the voltage decay of the electrode is correlated to Mn4+/Mn3+ redox activation and subsequent cation disordering, which can be remarkably suppressed via simple compositional tuning to induce the formation of Ni3+ in the pristine material. By implementing our new strategy, the Mn4+/Mn3+ reduction is subdued by an alternative redox reaction involving the use of pristine Ni3+ as a redox buffer, which has been designed to be widened from Ni3+/Ni4+ to Ni2+/Ni4+, without compensation for the capacity in principle. Negligible change in the voltage profile of modified LLO is observed upon extended cycling, and manganese migration into the lithium layer is significantly suppressed.
In the second part of the talk, I will discuss about transition metal (TM) migration, which is now understood to be the critical factor triggering the anionic redox as well as the phase transition, although the origin is still under debate. A better understanding of the specific TM migration behavior and its effect during charge/discharge would thus enable further development of this class of materials. I will show that the unique TM migration during charge/discharge significantly alters the lithium diffusion mechanism/kinetics of LLO cathodes. I present clear evidence of the much more sluggish lithium diffusion occurring during discharge (lithiation) than during charge (de-lithiation), which contrasts with the traditional lithium diffusion model based on simple topotactic lithium intercalation/deintercalation in the layered framework. The reversible but asymmetric TM migration in the structure, which originates from the non-equivalent local environments around the TM during the charge and discharge processes, is shown to affect the lithium mobility. This correlation between TM migration and lithium mobility led us to propose a new lithium diffusion model for layered structures and suggests the importance of considering TM migration in designing new LLO cathode materials.
Anomalous Segregation in Lithium-Rich Layered Oxide Uncovers New Theoretical Design Rule for Stable Cathode in Lithium-Ion Battery
Authors: Xin Huolin , Lin Ruoqian , Hu Enyuan , Bak Seong-Min , Yu Xiqian , Persson Kristin A , Wu Qin , Yang Xiao-Qing 
Published: February 2020

Here we report the TEM, X-ray, and first-principle investigation of a promising high-capacity lithium-rich 3d-4d (Mn-Ru) transition-metal layered compound. The incorporation of 4d transition metals here offers an uncharted phase space for mechanistic exploration as compared to the well documented 3d transition metal (TM) oxides. Using state-of-the-art electron and X-ray based techniques, we find surprisingly, after cycling, ruthenium segregates out as metallic nanoclusters on the reconstructed surface. Our calculations show that the unexpected ruthenium metal segregation is due to its thermodynamic insolubility in the oxygen deprived surface. This insolubility can disrupt the reconstructed surface, which explains the formation of a porous structure in this material. The revealed mechanism allows us to provide predictive guidance for the future design of lithium-rich as well as stoichiometric layered cathode materials.
This research used resources of the Center for Functional Nanomaterials, which is a U.S. DOE Office of Science Facility, and the Scientific Data and Computing Center, a component of the Computational Science Initiative, at Brookhaven National Laboratory under Contract No. DE-SC0012704. Dr. Enyuan Hu, Dr. Seongmin Bak, and Dr. Xiao-Qing Yang were supported by the Assistant Secretary for Energy Efficiency and Renewable Energy, Vehicle Technology Office of the U.S. Department of Energy through the Advanced Battery Materials Research (BMR) Program, including Battery500 Consortium under Contract DE-SC0012704. Work done by R.Z. is partially supported by the U.S. Department of Energy’s Office of Energy Efficiency and Renewable Energy (EERE) under the Award Number: DE-EE0008444. The work at IOP was supported by funding from Ministry of Science and Technology of China (Grants 2016YFA0202500) and the National Natural Science Foundation of China (51822211). H.C. and J-C.Z. were supported by the National Natural Science Foundation of China (51661135011). This research used resources 8-ID, 23-ID-2, and 28-ID-2 of the National Synchrotron Light Source II, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Brookhaven National Laboratory under Contract No. DE-SC0012704. This research used resources of beamline 8.0.1 of the Advanced Light Source, which is a DOE Office of Science User Facility under contract no. DE-AC02-05CH11231. We acknowledge the technical support from beamline scientists Dr. Jianming Bai and Dr. Eric Dooryhee at the XPD beamline of NSLSII.
Electrochemical Modeling on Crack Propagation within Ni-Rich Layered Cathode Materials
Authors: Park Sunho , Park Joonam , Song Jihun , Ryou Myung-Hyun , Lee YongMin 
Published: February 2020

Rechargeable lithium-ion batteries (LIBs) are being actively applied to energy storage systems (ESSs) and electric vehicles (EVs) because of their high energy density and long-life characteristics. Essential to the success of these efforts is warranty for not only battery performance but also reliability, which needs to understand the underlying degradation mechanism. Particularly, as the Ni content in cathode active materials increases, crack formation and propagation within the particle has been investigated as one of main causes for LIB degradation. However, although the formation of this crack is highly related to the number of cycles and the state of charge (SOC), the related research is still stayed in place.
In this study, a new electrochemical model for lithium ion batteries is proposed based on theoretical equations of crack propagation. We aim to model the phenomenon of crack propagation after cycling in different depth of discharge (DOD) levels using 18650 cells, whose chemistry is LiNi0.8Co0.15Al0.05O2/Graphite. In particular, since LiNi0.8Co0.15Al0.05O2 has a form of secondary particle, its degradation is closely related to cracks within the particle when it is charged to high voltage over long-term cycling. And it has been found the range of SOC has a greater impact on degradation than the number of cycles. We try to establish the model by giving the degradation impact of SOC and the number of cycles differently. This choice of model brings a cycle life prediction with a few parameters to be fitted to particular cells.
Implementation of Tin Dioxide/Graphene/Graphene Oxide for High Capacity and Long Cycle Life Lithium Ion Batteries
Authors: Dorvilien Valerio , LopezdeVictoria Monica , Dorvilien Valerio , Mendoza Frank , Weiner Brad R. , Morell Gerardo 
Published: February 2020

We explored a non-conventional process to synthesize SnO2/G/GO composite powder which is a conformal structure that was characterized under different techniques. Comprehensive analysis of the structural and chemical properties reveals that the material consists of highly dispersed SnO2 nanoparticles in G/GO matrix.
We examine the electrical conductivity of the electrodes by atomic force microscope (AFM), scanning electron microscope (SEM) and transmission electron microscope (TEM). The SnO2/G/GO composite exhibited high discharge capacity and excellent electrochemical performance as anode material for lithium ion Battries. The quantitative/qualitative results show that G/GO is providing contact areas which results in more energy density at the interface electrode/electrolyte and that the SnO2 provides additional ions to the EDL and the electrochemical process.
A Scalable Froth-Flotation Separation Process for Direct Recycling of Li-Ion Batteries and Its Technical Feasibility
Authors: Shin Hosop , Zhan Ruiting , Dhindsa Kulwinder , Pan Lei , Han Taehee 
Published: February 2020

The increasing demand for Li-ion batteries (LIBs) in hybrid and electric vehicles had led to a significant increase in the volume of new and end-of-life LIBs. For this reason, recycling of spent LIBs has attracted significant attention in recent years for future sustainability. Different from existing recycling methods such as pyrometallurgical and hydrometallurgical methods, direct recycling method recovers cathode and anode active materials directly in reusable forms at a low cost. This process consists of two steps: 1) liberation and separation, and 2) re-functionalization (or re-lithiation). Many previous studies have been focusing on the second step only. To successfully implement the direct recycling process, development of a scalable and environmentally friendly separation process for battery active materials while preserving their functional integrity is necessary. To date, no studies have been conducted to evaluate the technical feasibility of such a scalable separation process for the direct recycling method.
In this work, a water-based recycling process was developed to recover cathode active materials from LIBs. In this recycling process, froth flotation technique was used to separate cathode active materials from a mixture of cathode and anode materials. A variety of electrochemical analyses of the recycled cathode active materials were systematically conducted to evaluate technical feasibility and understand current challenges of this recycling process. The present research demonstrated that the use of kerosene as the collector in the froth flotation process improved the purity of produced cathode active materials, and the recycled cathode materials preserved their original electrochemical reactivity. Cycle performance (up to 200 cycles) and rate capability (up to 1C) of the recycled cathodes were comparable to those of a pristine cathode. However, the reversible capacity of the recycled cathodes was slightly lower than that of a pristine cathode because of cell polarization. The polarization caused by electrode wettability and surface impurities on the recycled cathodes was identified as a key challenge that needs to be addressed further. This work will provide valuable insights into further development of a froth flotation-based recycling process which can be implemented in the direct recycling process.
Recovery of Unwanted Lithium from Graphite Anodes Via Thermal Gradient
Authors: Atkinson Robert W. , Carter Rachel E. , Love Corey T 
Published: February 2020

Thermal management is a known design consideration for safe and stable cycling of Li-ion batteries. Active thermal management systems attempt to maintain isothermal control to limit thermal excursions that can lead to premature cell performance loss and safety failures. Low temperature cycling is one example of unsafe Li-ion battery operation, which has been shown to limit cycle life by lithium plating and can also lead to dendrite nucleation and growth that can cause internal short circuits and battery failure. However, it can be assumed that these engineering controls cannot consistently maintain the safe isothermal condition and localized thermal gradients will develop within cells.
We previously showed that the application of an external thermal gradient has a profound effect on cell electrochemical processes. For lithium metal symmetric cells, the direction of an interelectrode thermal gradient dictates lithium plating morphology and determines whether unstable, dendrite growth or stable plating occurs (1). We have also demonstrated that applying a thermal gradient (cold anode, warm cathode) allows plating lithium on graphite on-demand, dramatically reducing cell capacity by loss of lithium inventory (2). In this way, a thermal gradient rapidly incites realistic cell failure modes, accelerating testing to battery failure to enable improved understanding of battery failure.
This talk focuses on the utility of reversing the direction of interelectrode thermal gradients to strip lithium from the graphite electrode. We use post mortem materials characterization techniques including X-ray diffraction (XRD), scanning electron microscopy (SEM), and Raman spectroscopy to characterize texture and morphology of the plated and lithium metal on graphite and confirm its recovery. A thermal gradient effectively restores battery health by modulating plating to recover lithium inventory and battery capacity; this thermal gradient reversal prevents internal short circuits from dendrite growth and ultimately extends battery lifetime in NMC|graphite cells. In addition to post mortem materials characterization, we use electrochemical impedance spectroscopy (EIS) and incremental capacity analysis to monitor lithium plating and stripping modulation.
References

A. Mistry, C. Fear, R. Carter, C. T. Love and P. P. Mukherjee, ACS Energy Letters, 4, 156 (2018).

R. Carter and C. T. Love, ACS Appl Mater Interfaces (2018).
Desalination Technologies Utilizing Solar Energy
Authors: Zheng Yanjie , Hatzell Kelsey B. 
Published: February 2020

Geographic areas that are rich in seawater or brackish water but lack freshwater resources require desalination technologies in order to meet water needs. Desalination processes are energy intensive, and thus there is a growing interest in coupling desalination with solar energy technologies (i.e. electrical or thermal energy sources). Three main approaches are: (1) photovoltaic-reverse osmosis (PV-RO), (2) solar-thermal desalination, and (3) solar-electrochemical1-4. The first approach creates electrical energy to drive a pressure driven membrane desalination approach and the second approach creates heat to drive a phase change separation process. Finally, the third approach is potentially the least well studied because most electrochemical separation technologies still reside at the benchtop scale. In this poster we theoretically evaluate the energetics and technoeconomics of various solar-desalination schemes and assess the potential of electrochemical technologies for industrial separations applications.
[1] Pugsley, A., Zacharopoulos, A., Mondol, J. D., & Smyth, M. (2016). Global applicability of solar desalination. Renewable energy, 88, 200-219.
[2] Mistry, K. H., McGovern, R. K., Thiel, G. P., Summers, E. K., Zubair, S. M., & Lienhard, J. H. (2011). Entropy generation analysis of desalination technologies. Entropy, 13(10), 1829-1864.
[3] Zheng, Y., Zhao, Y., Liang, S., & Zheng, H. (2018). Thermo-Economic Optimization of an Idealized Solar Tower Power Plant Combined with MED System. Entropy, 20(11), 822.
[4] Warsinger, D., Mistry, K., Nayar, K., Chung, H., & Lienhard, V. (2015). Entropy generation of desalination powered by variable temperature waste heat. Entropy, 17(11), 7530-75
Electrochemistry Research in the Stickney Lab: A Brief Summary of Dr. John Stickney's Past and Present Research
Authors: Howell Pauline , Stickney John Lewellen , Sisk Peter 
Published: February 2020

Electrochemical atomic layer deposition (E-ALD) is a method deeply developed and furthered by the research of Dr. John Stickney. This talk will focus on a brief summary of his past research as well as present work conducted in this lab. E-ALD is a method where one component is deposited followed by another, keeping the conditions simple by operating at room temperature and using a three electrode flow cell.1 This type of deposition process adds control to the compound growth by limiting the amount of deposit to less than a monolayer per deposition cycle. A brief overview of the history of advances made in E-ALD will be given, leading into different materials that have been developed. Development of various CdTe deposition techniques will be discussed as well as the investigations into the deposition of germanene.2-4 Finally new work on GeSe will be discussed. Investigations into the effect of pH on the electrochemical deposition of Ge and Se were done. Deposition studies of Ge on Se-coated Au electrodes were carried out as well as Se on Ge-coated Au electrodes at different pHs in an effort to find conditions where a GeSe thin film can be deposited.
References

Stickney, J. L.; Villegas, I.; Suggs, D. W.; Gregory, B. W., Electrochemical Atomic Layer Epitaxy (ECALE). Abstr Pap Am Chem S
1991,
201, 289­Coll.

Zhang, X.; Shen, S.; Howell, P.; Cheng, W.; Mubeen, S.; Stickney, J. L., Journal of The Electrochemical Society
, 166 (5) H3249-H3256 (2019)

ACS Nano2017, 11, 9, 9481-948

Journal of The Electrochemical Society, 164 (7) D469-D477 (2017)
(Invited) Characterizing Li-Ion Battery Extreme Fast Charging through in Situ Measurement of Temperature Distributions
Authors: Huang Shan , Wu Xianyang , Cavalheiro Gabriel M. , Du Xiaoniu , Liu Bangzhi , Du Zhijia , Zhang Guangsheng 
Published: February 2020

Extreme fast charging (XFC) capability is important for wider adoption of battery electric vehicles (1). However, barriers to XFC still exist, including rapid heat generation and potential overheating of Li-ion batteries. Both life and safety of Li-ion batteries could be jeopardized by overheating (2-4). Moreover, temperature distributions in individual Li-ion cells would be non-uniform during XFC (5) due to low thermal conductivity of Li-ion cell materials (6, 7). The non-uniform temperature distribution could then lead to non-uniform degradation and underestimate of overheating by monitoring cell surface temperature. Indeed, a recent numerical modeling study (5) predicts overheating and non-uniform temperature distributions in Li-ion cells during XFC.
In this presentation we will report characterization of Li-ion cell behaviors during XFC through in situ measurement of temperature distributions. Figure 1 shows representative results of a 2Ah Li-ion cell during 1C, 3C, 5C and 7C constant current charging followed by 4.2V constant voltage charging. It can be seen that all temperatures increase much more rapidly during 7C charging than during 1C charging. It can be also seen that the difference between internal core temperature and external surface temperature during 7C charging is much larger than that during 1C charging. The results suggest overheating and obvious non-uniform temperature distributions during XFC even for a small Li-ion cell with capacity of 2 Ah and thickness of only 4 mm.
More results, including heat generation rate, voltage behaviors, effects of cooling, and degradation will be presented and discussed.

Figure 1. Rise of local temperatures in a 2 Ah Li-ion cell during 1C, 3C, 5C and 7C constant current charging followed by 4.2V constant voltage charging with forced convection air cooling

Figure 1