bluuebunny/crossref_metadata_2025_split huggingface dataset:
Advanced Multiphase Silicon-Based Anodes for High-Energy-Density Li-Ion and Li-Air Batteries
Authors: Golodnitsky Diana , Goldstein Keren , Freedman Kathrin , Menkin Svetlana , Peled Emanuel 
Published: February 2020

Given that lithium-ion and lithium-air batteries are the preferred choice for EVs and plug-in applications for the next 10–15 years, the focus is on improving their safety and performance. New, higher-capacity materials are required in order to address the need for greater energy density, longer cycle life and safer high-power operation. Silicon offers the highest gravimetric and volumetric capacity as an anode material (e.g. Li22Si5: nearly 4,200mAh/g, 9,800mAh/mL). The lithium-rich silicon compounds have high melting points. Their higher working potentials (vs. Li) eliminate the possibility of metallic-lithium deposition due to overcharge. Silicon is the second-most abundant element in the earth’s crust, and it is environmentally benign. Unfortunately, Si-based electrodes typically suffer from large volume changes (up to 420%) during insertion and extraction of lithium. This is followed by cracking and pulverization of silicon, which in turn, leads to the loss of electrical contact, unstable SEI and eventual capacity fading.
We have developed two synthetic routes for the preparation of core-shell silicon multiphase composite particles. We studied the process of formation of the protective SEI layer on the anode nanoparticles and tested small laboratory-prototype cells with advanced anodes. The methods of attachment of silicon nanoparticles to carbon nanotubes (multi-wall carbon nanotubes (MWCNT)) were developed with the purpose of creating silicon anodes supported by a strong, rigid and high-electrically-conducting matrix. The methods are based on the silanization process or pyrolysis. STEM analysis showed that silicon particles are dispersed uniformly on the surface of the MWCNT. ESEM images indicated the formation of silicon nanoparticles wrapped by carbon nanotubes and coated by nanometer thick amorphous carbon. TEM, EELS and XPS tests confirm the formation of a layer of carbon on top of the silicon nanoparticles and Si-C bonding (Fig.1). The feasibility of using electrophoretic deposition for the preparation of composite silicon anodes coated by a ceramic-in-polymer protective layer has been proven.
Li/LiPF6 EC:DEC/Si-C-MWCNT cells with anodes composed of about 50% core-shell Si-C composite exhibited de-intercalation capacity of 1373mAh/gSi at the 50th cycle and 1021mAh/cm2 at the 410thcycle. Li/LiTFSI-Pyr14/Si-C-MWCNT cells ran for more than 30 cycles with capacity of 1500mAh/gSi. Doped Si-alloy nanoparticles were formed by electrochemical means. The anodes are being tested.

Acknowledgments

Research is funded by EU FP7, contract no. 265971 and by Israel Academy of Science
Monitoring the Location of Cathode Reactions in Li-O2systems
Authors: Landa-Medrano Imanol , Pinedo Ricardo , Ruiz de Larramendi Idoia , Ortiz-Vitoriano Nagore , Jimenez de Aberasturi Dorleta , Ruiz de Larramendi José Ignacio , Rojo Teófilo 
Published: February 2020

Lithium-oxygen (Li-O2) batteries have been considered as a promising alternative for high energy storage systems due to their exceptional theoretical energy density. However, many obstacles need to be overcome before developing a safe, green and efficient commercial dispositive [1,2].
One of the key issues of these batteries is the employed electrolyte. Carbonates have been inherited from Li-ion technology, becoming their use popular in the early steps of development of Li-O2 systems. However, due to their decomposition at high potentials [3,4], they are slowly being replaced by other type of electrolytes such as glymes or ionic liquids. In order to study these processes, in addition to common electrochemical characterisation techniques, X-ray photoelectron spectroscopy (XPS), impedance spectroscopy and transmission electron microscopy (TEM) have proved to be fundamental techniques for in situ monitoring of reaction products that take place during charge and discharge [5-7]
In this work, it is proved that the use of organic solvents with low oxygen solubility reduces the active area for the oxygen reduction reaction (ORR) to the oxygen cathode electrolyte triple interface (OCETI). For this aim electrodes loaded with different carbon masses have been cycled in different conditions and post-mortem analyzed by means of X-ray diffraction (XRD), scanning electrode microscope (SEM) and x-ray photoelectron spectroscopy (XPS). The obtained data evidence that the most of the cathode is not active in each stage of the cycling process (Figure 1.a and 1.b). Consequently, expressing the obtained specific capacity values in mA h g-1 units or the current densities in mA g-1 becomes undesirable as it leads to non reasonable comparisons. Moreover, the analysis of the cyclability has evidenced the competition between the OCETI (Figure 1.c) and the applied intensity (Figure 1.d) as the main limiting factors for the performance of these Li-O2 systems.
References:
[1] G. Girishkumar, B. McCloskey, A.C. Luntz, S. Swanson, W. Wilcke, J. Phys. Chem. Lett. 1 (2010) 2193−2203.
[2] K.M. Abraham, Z. Jiang, J. Electrochem. Soc. 143 (1996) 1−5.
[3] S.A. Freunberger, Y. Chen, N.E. Drewett, L.J. Hardwick, F. Bard, and P.G. Bruce, Angew. Chem. Int. Ed. 50 (2011) 8609−8613.
[4] Y. Chen, S.A. Freunberger, Z. Peng, F. Bardé, P.G. Bruce, J. Am. Chem. Soc. 134 (2012) 7952−7957.
[5] Y.-C. Lu, B. M. Gallant, D. G. Kwabi, J. R. Harding, R. R. Mitchell, M. S. Whittingham and Y. Shao-Horn, Energy Environ. Sci 6 (2013) 750-768.
[6] I. Landa-Medrano, I. Ruiz de Larramendi, N. Ortiz-Vitoriano, R. Pinedo, J.I. Ruiz de Larramendi and T. Tojo, J. Power Sources 249 (2014) 110-117
[7] L. Zhong, R. R. Mitchell, Y. Liu, B. M. Gallant, C. V. Thompson, J. Yu Huang, S. X. Mao and Y. Shao-Horn, Nano Lett. 13 (2013) 2209-2214.
Suppression of Unwanted Reactions on the Carbon-Based Air Electrode
Authors: Yoon Dae Ho , Park Yong Joon 
Published: February 2020

In the past decade, lithium ion batteries have played a dominant power source for items ranging from portable electronics to hybrid electric vehicles. However, they still do not offer enough energy density to meet the ever-increasing demands of many applications despite extensive research to explore ways to increase their charge-storage capability. As a new energy storage system, Li-air batteries have attracted numerous attentions because they have the potential to provide several times higher capacity than commercial Li-ion cells [1-2]. Li-air batteries have been developed in different types according to the electrolytes employed, such as aqueous, non-aqueous, and hybrid systems. Because of relatively simple configuration and large real capacity, non-aqueous system is most active all Li-air batteries. Much research effort has been devoted in order to enhance the performance of Non-aqueous Li-air cells [3-4]. However, they still are facing fundamental and practical challenges such as low rate capability, limited cycle life resulting from the instability of the electrode and electrolyte, and significant overpotential on charge due to slow kinetics of dissociation from reaction products (such as Li2O2). These critical issues are highly attributed to the air electrode, the reaction place between lithium ion and oxygen, and electrolyte directly contact with electrode. In this study, the suppression of unwanted reactions on the air electrode during cycling is main issue. With aim to suppress the unwanted reactions, the surface of carbon was passivated by stable materials. The surface defects of carbon facilitate unwanted electrolyte decomposition reactions during cycling, which deteriorate the cyclic performance of air cell [5-6]. So the passivation of carbon is expected as an effective approach for enhancing the cycling performance of the Li-air batteries.
References
[1] A. Kraytsberg, Y. Ein-Eli, J. Power Source. 196 (2011) 886
[2] A. Débart, J. Bao, G. Armstrong, P.G. Bruce, J. Power Sources 174 (2007) 1177
[3] D. Capsoni, M. Bini, S. Ferrari, E. Quartarone, P. Mustarelli 220 (2012) 253
[4] Z. Peng, S. A. Freunberger, L. J. Hardwick, Y. Chen, V. Giordani, F. Bardé, P. Novák, D. Graham, J. M. Tarascon, and P. G. Bruce, Angew. Chem. Int. Ed. (2011) 50, 1
[5] J. Lu, Y. Lei, K. C. Lau, X. Luo, P. Du, J. Wen, R. S. Assary, U. Das, D. J. Miller, J. W. Elam, H. M. Albishri, D. A. El-hady, Y. K. Sun, L. A. Curtiss, K. Amine, Nat. Commun. 4 (2013) DOI: 10.1038/ncomms3383.
[6] B. D. McCloskey, A. Speidel, R. Scheffler, D. C. Miller,V. Viswanathan, J. S. Hummelshøj, J. K. Nørskov and A. C. Luntz, J. Phys. Chem. Lett. 3 (2012) 997.
Li-S Cathodes with Extended Cycle Life By Sulfur Encapsulation in Disordered Micro-Porous Carbon Powders
Authors: Aurbach Doron , Rosenman Ariel , Salitra Gregory , Elazari Ran , Garsuch Arnd 
Published: February 2020

Sulfur cathodes have excellent theoretical properties for use as positive electrodes in rechargeable lithium batteries, but lack long-term stability required of practical secondary battery systems. To deal with this issue, high capacity Lithium-Sulfur cathodes with extended cycle life were prepared through thermal encapsulation of sulfurat 155°C in disordered micro-porous carbon powders that have high specific surface-area of ~ 2000 m2/g. The electrodes have been characterized using X-ray diffraction (XRD), Scanning electron microscopy/energy-dispersive X-ray (SEM/EDX), Raman spectroscopy, Thermal Gravimetric Analysis (TGA) and Gas adsorption technique. By using microporous carbon as matrices for sulfur cathodes and lithium nitrate as an additive to the electrolyte solution, that suppresses the shuttle phenomena in Li-sulfur batteries, we managed to achieve a reversible capacity of over 500mAh/g after 1000 cycles (Figure 1) with a Columbic efficiency approaching 100% throughout cycling. The sulfur composite cathodes of 14mm in diameter (area of ~1.54 cm2) and active material load of more than 1mg/cm2were tested in a two electrodes configuration with coin-type cells (2523,NRC, Canada). Electrolyte solution was DOL and DME (1:1 ratio) with 10% LiTFSI and 2% of LiNO3(by weight).
The influence of the volume of the electrolyte solutions in Li-S cells was further evaluated by analyzing their voltage profiles during cycling.
Li-Oxygen Versus Li-Ion Battery Systems: Chances and Challenges for Utilization in the Automotive Industry
Authors: Traußnig Thomas , Fink Clemens , Lukacs Andras , Stuetz Harald , Hennige Volker 
Published: February 2020

Due to its ultra-high energy density Li-oxygen battery technology is one of the first-choice candidates for the realization of full electric vehicles capable of covering a driving range beyond 500 km [1].
The present contribution deals with the development of a full system for operating Li-oxygen technology in an automotive environment.
Electrochemical models based on the work of Doyle and Newman [2] as well as battery system requirements form the fundament for developing a suitable Li-oxygen cell design (i.e. simulation of reactant flow). The integration of the cells into a full battery system is elaborated in detail with special focus on the requirements of Li-oxygen technology [3]. For the Li-oxygen battery system an operation strategy is described. A discussion of range- and power capabilities as well as predictions for weight and volume of the full battery system for achieving a vehicle range beyond 500 km is presented. With the help of statistical methods safety aspects of Li-oxygen battery pack design are studied. In addition a comparison between conventional Li-ion technology and Li-oxygen technology on battery system level is drawn.
Our findings point out that both Li-oxygen and Li-ion technology feature mutually beneficial properties with respect to energy and power density and that a combined use of these technologies is highly recommendable for automotive applications.
[1] Girishkumar et al, J. Phys. Chem. Lett. 1, (2010), p.2193-2203
[2] J. Adams, M. Karulkar, J. Power Sources 199 (2012) 247-255
[3] Traußnig et al, Poster Session, Kraftwerk Batterie (2013)

Acknowledgement

The research leading to these results has received funding from the European Union’s Seventh Framework Program under EC-GA No. 265971 ‘LABOHR’.
The attached image shows a Li-oxygen pack design which is separated into three different areas (oxygen uptake area in yellow, cell assembly in blue and E/E unit in red -> see also integrated caption). The simulation on the upper right side of the image studies the impact of the reactant flow on cell chemistry, whereas the simulation on the lower right side of the image investigates the impact on system level.
In Situ Synchrotron XRD on a Capillary Li-O2 Battery Cell
Authors: Storm Mie Møller , Johnsen Rune E. , Norby Poul 
Published: February 2020

In situ studies give an opportunity to explore systems with a minimum of external interference. As Li-air batteries hold the promise for a future battery technology the investigation of the discharge and charge components of the cathode and anode is of importance, as these components may hold the key to making a large capacity rechargeable battery[1]. Different design for in situ XRD studies of Li-O2 batteries has been published, based on coin cell like configuration[2] [3] or Swagelok designs [4]. Capillary batteries have been investigated for the Li-ion system since its development[5], but no capillary batteries of Li-air has yet been designed. Some of the advantage of the capillary battery design lies in its ability to separate the cathode and anode and avoid the use of glass fiber or separators, which may enable ex situ analysis of battery components. The battery design consist of a electrolyte filled capillary with anode and cathode in each end suspended on stainless steel wires, the oxygen in-let is placed on the cathode side of the capillary with a flushing system for oxygen in-let. In this study we present a flexible design of a capillary based Li-O2 battery with discharge and charge investigated in dimethxyethane (DME) with synchrotron XRD. The in situ study in these batteries show clearly how Li2O2 precipitates on the cathode side of the battery during discharge (see Figure), as the Li2O2 reflections at 21.2°, 22.5° and 37.1° grows. The reflection at 27.8, 28.4 and 32.16 is from a stainless steel wire where the cathode is attached. The in situ XRD measurements show how the Li2O2 growth depend on current discharge rate and how the FWHM changes dependent on reflection and charge/discharge.Several cells were tested both ex situ and in situ, and in situ XRD for 1st discharge/charge and 2nd discharge/charge of the battery cell were measured, to give a better understanding of the electrochemistry in the Li-O2battery.
1. Girishkumar, G., et al.. The Journal of Physical Chemistry Letters, 2010. 1(14): p. 2193-2203.
2. Lim, H., E. Yilmaz, and H.R. Byon, The Journal of Physical Chemistry Letters, 2012. 3(21): p. 3210-3215.
3. Ryan, K.R., et al.,. Journal of Materials Chemistry A, 2013. 1(23): p. 6915-6919.
4. Shui, J.-L., et al., Nat Commun, 2013. 4.
5. Johnsen, R.E. and P. Norby,. Journal of Applied Crystallography, 2013. 46(6): p. 1537-1543.
Estimating Thermal Parameters of Large-Format Laminated Lithium-Ion Batteries Using Thermal Impedance Spectroscopy
Authors: Wu Bin , Zhang Jianbo , Zhou Jun , Li Zhe 
Published: February 2020

The accuracy of battery thermal parameters is crucial to the accuracy of thermal simulations for batteries. Given the structural characteristics of the large-format laminated lithium-ion battery [1], effective methods to determine multiple thermal parameters, such as the thermal conductivity and the specific heat capacity, should be developed to achieve better prediction of battery thermal behaviors.
Generally, the methods for measuring the thermal parameters of batteries can be divided into two categories, the time-domain method and the frequency-domain method. The authors developed a joint computational and experimental time-domain method to estimate the multiple thermal parameters for a 25 Ah laminated lithium-ion battery both in-situ and simultaneously [1]. However, the battery temperature changed from 25 to 35°C in the experiment, hence the estimated thermal parameters were the average properties over 25~35°C. In contrast, the change in the temperature of the sample can be greatly reduced in the frequency-domain method, making it possible to obtain the thermal parameters at different temperatures.
In this work, a frequency-domain method, the thermal impedance spectroscopy (TIS) method is used to simultaneously and in-situ determine two thermal parameters, i.e. thermal conductivity and specific heat capacity, for the large-format laminated lithium-ion battery.
In the experiment, a planar electric heater is sandwiched between two identical batteries (25 Ah, 250 mm × 220 mm × 7.2 mm，NMC-LMO/Graphite), as shown in Fig. 1(a). The electric power for the heater is adujusted at different frequencies (0.1, 0.2, 0.4, 0.6, 0.8 and 1 mHz) and the temperature response on one outer surface is recorded with the attached thermocouple. The entire set-up is placed in an environment chamber.
The heat transfer behavior between the heating power and the temperature response is examined in the frequency domain. An equivalent thermal circuit including thermal capacity and resistance is introduced to derive the analytical expression of thermal impedance, as shown in Fig. 1(b). The thermal circuit is simplified from the 1D heat conduction model, which also takes the covering aluminum-plastic film into account. The thermal conductivity and capacity of the battery core are estimated using the least-square fitting algorithm. The experimental and fitted thermal impedance are shown in Fig. 1(c).
The estimated parameters are validated against the results from the accelerating rate calorimeter (ARC), the heat flow calorimeter (HFC) and the joint computational and experimental time-domain method [1].

Reference

[1] Zhang J, Wu B, Li Z, et al. Simultaneous Estimation of Multiple Thermal Parameters of Large-Format Laminated Lithium-Ion Batteries[C]//Vehicle Power and Propulsion Conference (VPPC), 2013 IEEE. IEEE, 2013.
Numerical Simulation and in-operando Measurement of the Local Temperature Evolution in a Lithium Ion Battery Cell
Authors: Heubner Christian , Schneider Michael , Junker Nils , Lämmel Christoph , Michaelis Alexander , Hess A. , Mortazavi B. , Roode-Gutzmer Q. , Yang H. , Bobeth Manfred , Cuniberti G. 
Published: February 2020

Aiming at a better quantitative understanding of the fundamental mechanisms that cause heat evolution in lithium ion batteries, theoretical modeling of the temperature evolution was performed associated with in-operando temperature measurements across the interfaces of a single lithium ion battery cell. For that purpose, an experimental setup has been developed at the Fraunhofer IKTS. The cylindrical electrode arrangement and the positioning of the thermocouples at specific interfaces within the lithium ion cell is illustrated in the figure. The success of this experimental approach has recently been demonstrated [1]. The present modeling is based on Newman's pseudo-2D model [2], extended however by including a radial spatial dependence of the electrochemical processes and SoC-dependent material properties. To evaluate the reliability of the electrochemical modeling, simulations of GITT experiments were compared with corresponding measurements using a 3-electrode arrangement. Calculations of the electric potential and current densities within the cell during charging and discharging yield the spatially resolved heat-source densities. The simulations enable the comparison of different contributions to the local heat generation. Reversible heat due to entropy changes, irreversible reaction heat, and ohmic heating within the electrode materials and the electrolyte are included in the temperature model as a function of the SoC for a wide range of charge/discharge rates. The effect of parameter variations on the temperature evolution has been extensively explored, particularly in view of different reported material properties [3]. Differences in the heat generation within the cathode, separator, and anode as a function of time, charge/discharge rate and SoC were successfully identified both theoretically and experimentally. Generally, the numerical results and the measurements reveal the significance of reversible heat effects due to electrochemical reactions under near equilibrium conditions, whereas Joule heating becomes important at high current densities. In-operando measurements allow time-resolved as well as SoC-dependend study of key parameters for the numerical simulation. The present work magnificently show the strong relation between the fundamental electrochemical processes and the resulting heat impact.

[1] C. Heubner, M. Schneider, C. Lämmel, U. Langklotz, A. Michaelis; In-operando temperature measurement across the interfaces of a lithium-ion battery cell; Electrochim. Acta, 113 (2013) 730-734.
[2] M. Doyle, T.F. Fuller, J. Newman; Modeling of galvanostatic charge and discharge of the lithium/polymer/insertion cell; J. Electrochem. Soc. 140 (1993) 1526-1533.
[3] M. Park, X. Zhang, M. Chung, G.B: Less, A.M. Sastry; A review of conduction phenomena in Li-ion batteries; J. Power Sources 195 (2010) 7904-7929
In-Situ Observation of Solid Electrolyte Interphase on LiCoO2 during Cycling to 4.5 V By AFM
Authors: Lu Wei , Zhang Jiansheng , Chen Liwei , Wu Xiaodong 
Published: February 2020

LiCoO2 is the most common cathode material for commercial lithium-ion batteries due to its high tap density, excellent cycling performance and high rate capability. Though LiCoO2 has a theoretical capacity of 274 mAh/g, its reversible capacity is limited to around 140 mAh/g when cycled between 3.0 V and 4.2 V vs Li metal. Increasing the upper cutoff voltage can extract more lithium ions beyond Li0.5CoO2, which can increase the reversible capacity of LiCoO2. However, the electrolyte will be oxidized at such high voltage, which will consume the electrolyte, and form solid electrolyte interphase (SEI) on the surface. The thickness, stability will influence the electrochemical performance of LiCoO2cathode at high voltage.
In this work, we used atomic force microscope (AFM) to study the properties and evolution of SEI films on LiCoO2 cathode during electrochemical cycling. Different structure and evolution processes of SEI on different crystal faces //(001) and „&die;(001) were observed in-situ during the electrochemical reaction. We also study the protecting effect of a thin layer of Al2O3 film on the surface of LiCoO2micro-crystal prepared by atomic layer deposition (ALD) technique.
Figure. (a) LiCoO2 micro-crystal prepared by melting-salt method. (b) LiCoO2 micro-crystal embedded in Al substrate. Topography images of LiCoO2 micro-crystal //(001) face obtained in-situ by AFM at original (c) and charged to 4.5 V (d). Topography images of LiCoO2 micro-crystal „&die;(001) face obtained in-situ by AFM at original (e) and charged to 4.5 V (f).