bluuebunny/crossref_metadata_2025_split huggingface dataset:
(Invited) Investigating Failure in Anode-Free Lithium-Metal Pouch Cells with Liquid Electrolytes
Authors: Weber Rochelle , Genovese Matthew , Louli Alexander J , Dahn Jeff R 
Published: February 2020

Anode-free, or zero-excess lithium-metal cells, promise higher energy density than existing lithium-ion batteries. However, the abysmal performance of cells with lithium-metal electrodes prevents them from being used in commercial products that require long-life: electric cars and energy storage products. Many researchers believe all-solid state cells are necessary to achieve the lifetime required for these applications, but solid electrolytes complicate cell manufacturing and incur the huge costs required to rebuild existing production facilities designed to handle cells with liquid electrolytes. If a long-life anode-free cell could be made using a liquid electrolyte, this would be the best path forward for fast and inexpensive introduction into the existing market.
In this work, baseline NMC532/Cu anode-free pouch cells with 1M LiPF6 in FEC:DEC (1:2 vol) were tested at 40°C, with C/5 charge and C/2 discharge between 3.6 V – 4.5 V. Cells with this electrolyte lose 80% of their initial capacity before 20 charge-discharge cycles. Liquid electrolytes with different lithium salts are tested and show improved performance. To investigate the capacity loss mechanisms, SEM is used to track lithium morphology, XPS is used to compare SEI composition, and liquid NMR is used to track the electrolyte volume and degradation at various points throughout cycling. The results of these experiments are used to guide further optimization of the electrolyte composition which give incremental improvements in capacity retention. With continued works towards understanding the failure of these cells, a commercializable anode-free lithium-metal cell with liquid electrolyte may be realized.
Effect of the Direct Pre-Lithiation on Cycling Performance of Li Ion Battery with Silicon-Containing Anodes
Authors: Kim Kyoung Hwan , Shon Jeong-Kuk , Park Hwi-Yeol , Jeong Huisu , Lim Sungjin , Heo Jin S. 
Published: February 2020

The desire to advanced lithium ion battery is growing with the expansion of electronic markets. Therefore, studies on making electrode materials with high energy density and long cycle life are actively conducted. Among those materials, silicon containing anode is one of the most important materials in making high energy density batteries because of the high theoretical capacity of silicon (~4200mAh/g). However, silicon containing anodes have the disadvantage of large initial irreversible capacity and continuous capacity loss due to large volume change of silicon. Because Li ions transferred from the cathode to the anode disappear without being reversibly used for charging and discharging, the capacity of the full cell becomes significantly smaller than expected. To solve this problem, pre-lithiation has been proposed as a powerful method which can be done through several methods including chemical and electrochemical pre-lithiation and pre-lithiation by direct-contact to lithium [1]. Pre-lithiation studies show that the Coulombic efficiency and discharge capacity dramatically increased.
In this research, we propose a method to improve a cycle life of Li ion batteries with silicon containing anodes by applying pre-lithiation to suppress the volume change of silicon. We applied a direct pre-lithation method to increase the cycle life through depositing Li onto the anode; which has an impact on the manufacturing process and the accurate controlling of Li amount. When the coin cell was fabricated with a high capacity cathode and a pre-lithiated silicon containing anode, we were able to obtain not only high discharge capacity (~18%) but also enhanced cycle life characteristics (~30%). In order to investigate the cause of improved cycle life of the cell, three electrode electrochemical experiments were conducted, and then the charged/discharged state of the anode and the cathode are separately extracted in the full cell profile. Analysis of the extracted profiles confirms that the end-voltage of the anode with accurate amount of extra Li is lowered, which means that the silicon in the anode did not completely shrink after discharge. This result demonstrates that the pre-lithiation method is effective in reducing the volume change of the silicon during cycling. Electrochemical impedance spectroscopy (EIS) and transmission electron microscopy (TEM) also supported the above results. We would like to share this result through the presentation and hope that this work will provide an effective method to build a long cycle life Li ion battery with silicon-containing anodes.

References

[1] Holtstiege, florian, et al, Batteries, 4.1 (2018): 4
Investigation of the Aging Behavior of Large Li-Ion Cells By a Novel Reassembling Process Using Coin Cells
Authors: Schmid Alexander Uwe , Birke Kai Peter 
Published: February 2020

Cycle aging tests of high-capacity (Ah) Li-ion cells are cost and time intensive since (i) high currents have to be applied (expensive measurement set-up) and (ii) predicting the cell aging behavior requires many tests with different parameters, e.g. temperature, C-rate, depth of discharge. Analyzing the aging behavior of large Li-ion cells by means of cycling the extracted cell material in small coin cells would tremendously lead to a faster and effective aging prediction. Many aging tests could be parallelized since only very low currents are needed. The condition for comparability between coin- and original cells is the same aging mechanism in both cell types and a reproducible coin cell assembly.
We test our coin cell assembly method on 40 Ah Li-ion pouch cells. We extract 62 coin cells out of three pristine 40 Ah pouch cells. The coefficient of variation in capacity of those coin cells at begin of life is 1.42% which is in the range of cell-to-cell variations of industrially produced cells at begin of life. Calendar and cyclic aging tests of 40 Ah pouch cells and extracted coin cells are conducted at different temperatures. Differential analyzes and impedance measurements help to detect the aging mechanisms of both cell types.
Finally, factors are introduced which may explain the measured offset in the respective aging curves.
The Impact of Calendering on the Electronic Conductivity Heterogeneity of Lithium-Ion Electrode Films
Authors: Hunter Emilee E , Vogel John E. , Wheeler Dean , Mazzeo Brian A 
Published: February 2020

Electrical conductivity is a key metric in the performance of lithium-ion batteries. However, accurately measuring the electronic conductivity nondestructively is difficult. We have developed a micro-four-line probe that has been used to make this measurement and to demonstrate the heterogeneity of electrical conductivity of lithium-ion electrodes on a mm scale [1]. Such heterogeneity or non-uniformity can cause the lithium ion battery to degrade unevenly overtime, which is undesirable.
The design of the micro-four-line probe has been improved into a flexible-four-line probe. This flexible measurement device is able to conform to the surface of the electrode, which improves the contact and the resulting electronic conductivity measurement. The flexible probe has been used to take accurate measurements of electronic conductivity and the contact resistance between the film and the current collector.
The microstructure of lithium-ion electrodes is another important characteristic that determines the performance of lithium-ion cells, including electronic and ionic conductivity of electrodes. Calendering, an important step in the manufacturing process, affects the microstructure as the film is compressed to a uniform thickness. Prior to calendering there are more substantial variations in the thickness of the electrode film, which constitutes surface roughness, as illustrated in the included thickness profile (figure).
The effect of calendering on the electronic heterogeneity of electrode films will be reported. The flexible probe will be used to measure the variation in electronic conductivity across the electrodes. A thickness analysis of the electrode films before and after calendering will complement the electrical measurements. This information increases our understanding of electrode manufacturing processes to allow for future optimization of these processes.

References:

Vogel et al., Electrochimica Acta 297, 820 (2019).

Figure 1
Synthesis and Characterization of Alumina-Doped Lithium Borovanadate Glasses As a Promising Cathode Material for Lithium Batteries
Authors: Kindle Michael , Kmiec Steven , d'Anciães Almeida Silva Igor , Martin Steve W , Eckert Hellmut , McCloy John S. , Song Min-Kyu 
Published: February 2020

The desire for scalable energy storage technologies with higher specific energy densities has been intensified. Along with this, exploring and advancing new chemistries could provide alternatives to cobalt-based cathodes in sourcing and cost. Glass electrodes can have a capacity of 500 mAh/g and can be produced in facile melt quench procedures. In particular, many vanadate glasses have shown the improved performance compared to their crystalline counterparts. For examples, vanadate glass-based electrodes have exhibited increased capacity, better cycling stability and higher rate capability when compared to those of crystalline counterparts, V2O5 based cathodes. The improved performance in the glass system is primarily linked to the lack of irreversible loss that occurs from a crystalline phase changes which do not occur in amorphous materials. Many vanadate-modified glass systems have been investigated. However, a more detailed analysis of the effect of lithium borates and how they alter the glass system has not been carried out. Here we report our systematic studies on the effects of altering the content of lithium borate ratios on the modification of the boron coordination, and thus the formation of boron superstructures and non-bridging oxygen (NBO) sites.
While the LiBO2-V2O5 system is reported as a promising high-performance cathode material, this glass system shows inconsistent glass formability in literature at high vanadium content, which is the electroactive species. An analysis of the effect of LiBO2 and Al2O3 on the vanadate glass system has been performed. X-ray photoelectron spectroscopy (V) and nuclear magnetic resonance (B-11) data show that alumina stabilizes and increases the BO3 coordinated species and decreases V4+ concentration which promotes VO4 chains to form with BO3 units, which is a stable glass structure according to literature. This is likely due to the [AlO4]- species, which requires charge compensation and reduces the amount of [BO4]- units that need to form. The lithium being attracted to the alumina structures likely limits how much lithium can then depolymerize the borovanadate glass network. The boron coordination changes and NBO sites that can be seen can also be related back to the rate capability, stability and performance of these glasses in electrochemical cells. More NBO sites means better ionic conduction and thus better rate capability and utilization of the active material. This extension of the borovanadate glass forming region, confirmed by various structural analysis, could improve the energy density of lithium batteries as well as offer viable alternatives to cobalt-based cathodes. Glass electrodes are a very promising alternative to traditional intercalation chemistries and warrant more exploration.
Unraveling the Role of Al Substitution in Anionic Oxygen Activity of Ni-Rich Layered Oxide Cathodes
Authors: Li Ning , Sallis Shawn , Papp Joseph K , McCloskey Bryan D. , Yang Wanli , Tong Wei 
Published: February 2020

Ni-based layered oxides have attracted great attention for the development of high energy and high capacity Li-ion cathodes. The most popular Ni-based cathodes, LiNi
x
Mn
y
Co1-x-y
O2 (NMC) and LiNi
x
Co
y
Al1-x-y
O2 (NMC), are indeed derivatives of LiNiO2 by partially substituting Ni with Co, Mn or Al. The current trend to develop high-Ni and low-Co or Co-free layered Ni-based oxide cathodes, makes a strong push to the limit of Ni content in such layered oxides, leading to many common properties with their parent compound, LiNiO2. In fact, lithium nickel oxide often exists off-stoichiometry because of the presence of Ni2+ in the Li layer, which blocks the Li+ diffusion pathway upon lithiation/delithiation. Therefore, a second metal of a minimal content, such as Co or Al, which can somehow facilitate the formation of layered structure is still needed, although they are not strongly favored due to cost and sacrifice upon the use of inactive Al.
In this work, a number of Al substituted lithium nickel oxides, LiAl
x
Ni1-x
O2 (0 ≤ x ≤ 0.20), have been synthesized via a solid state reaction, showing good R
m layered structure. Along with their parent LiNiO2, the oxygen activity in these compounds have been studied using combined synchrotron X-ray absorption spectroscopy (XAS), resonant inelastic X-ray scattering (RIXS) and differential electrochemical mass spectrometry (DEMS). The goal of this research is to elucidate the role of Al on the anionic oxygen activity in Ni-based layered oxides, including both reversible anionic oxygen redox and irreversible oxygen release during the electrochemical process. The electronic structure of transition metal and O was investigated at different states of charge to obtain a complete picture of cationic and anionic redox during the charge/discharge process. Beyond the redox chemistry, the effect of Al substitution on the phase transformation at highly delithiated states, dominated by H2 to H3 phase transformation for LiNiO2, as well as thermal stability was carefully studied. We hope this work helps provide a comprehensive picture of the role of Al substitution on the overall performance of Ni-based layered oxide cathodes.
Understanding Surface Reactivity on Ni-Rich Layered Oxide Cathodes
Authors: Chen Guoying , Zhu Jian 
Published: February 2020

The mass market penetration of electric vehicles demand lithium-ion batteries (LIBs) that deliver higher energy density, longer cycle life and better safety. [1] Layered lithium transition-metal oxides, particularly Ni-rich lithium nickel manganese cobalt oxides (LiNi
x
Mn
y
Co1-x-y
O2, x ≥ 0.5, referred to as NMC), are currently considered most promising cathode materials in meeting these requirements. The instability of NMC-based electrode surface, however, prevents them from stable high-voltage operation which is needed for achieving high energy density. [2,3] Insights into the mechanisms governing these instabilities are elusive due to the complex nature of these oxides.
Cathode materials are traditionally prepared by high-temperature ceramic methods which produce aggregated particles with significant inhomogeneity that can contribute to additional challenges in diagnostic studies and data interpretation. In our research, crystal samples with excellent uniformity and well-controlled physical properties are prepared. [4] For example, Figure 1 shows a series of NMC crystal samples with various morphologies. This provides a model platform to investigate the relationships among specific properties, surface chemistry and electrochemical performance without ambiguity. In this presentation, we show the specific role of chemical composition, elemental segregation, particle size and morphology on surface reactivity. Design strategies for better performing NMC cathode materials will also be discussed.

References

S.-T. Myung; F. Maglia; K.-J. Park; C. S. Yoon; P. Lamp; S.-J. Kim; Y.-K. Sun, ACS Energy Lett.
2017, 2, 196.

F. Schipper; E. M. Erickson; C. Erk; J.-Y. Shin; F. F. Chesneau; D. Aurbach, J. Electrochem. Soc.
2017, 164, A6220.

W. Li; B. Song; A. Manthiram, Chem. Soc. Rev.
2017, 46, 3006.

J. Zhu and G. Chen, J. Mater. Chem. A
2019,
7 (10), 5463.

Figure 1. SEM images of synthesized NMC crystal samples with four differet morphologies: a) octahedron, b) truncated-octahedron, c) polyhedron and d) platelet.

Figure 1
Cobalt-Based Lithiated Spinel Oxide As a Novel Zero-Strain Cathode
Authors: Lee Eungje , Han Jinhyup , Kwon Bob Jin , Dogan Fulya , Croy Jason R. , Thackeray Michael M. 
Published: February 2020

Zero-strain electrode materials that exhibit extremely small volume changes during intercalation reactions provide unique opportunities for highly stable lithium batteries. In particular, intecalation-induced strain in electrodes is a major factor in the degradation of advanced lithium batteries. For example, recent studies of high-performance Ni-rich layered cathodes unequivocally show a clear correlation between particle fracture, due to anisotropic volume expansion of polycrystalline grains, and continuously increasing cathode impedance.[1] Such chemo-mechanical behavior of electrode materials is even more critical to all-solid-state batteries in which the solid-solid interface between the electrode and solid electrolyte is prone to cracking and disintegration, even with small volume mismatches during electrochemical cycling. The best known zero-strain electrode material is the Ti-based spinel, Li4Ti5O12, that has been developed as a stable anode. Recently, LiRh2O4 spinel has been reported as a zero-strain cathode that operates at 3.2 V vs. Li/Li+,[2] however, its practical use is limited by the high cost of the precious metal, rhodium. A more feasible zero-strain cathode candidate is the ‘low-temperature’ (LT) form of LiCoO2, which adopts a cubic, lithiated spinel structure, Li2[Co2]O4.[3,4] On lithium extraction, LT-LiCoO2 provides an attractive 3.6 V vs Li. However, despite the high operating voltage and minimal volume change, this zero-strain material has received little attention since its discovery because of its poor cycling stability. In this presentation we report that cation substitution greatly improves the electrochemical perperties of LT-LiCo1-xMxO2 electrodes (M = cations). The different effects of various cation substituents on electrode performance will be compared and the zero-strain intercalation mechanism in LT-LiCo1-xMxO2 will be discussed.

References

[1] D. Miller, C. Proff, D.P. Abraham, and J. Bareno, Adv. Energy Mater., 3, 1098 (2013).
[2] Y. Gu, K. Taniguchi, R. Tajima, S.-i. Nishimura, D. Hashizume, A. Yamada, and H. Takagi, J. Mater. Chem. A 1, 6550 (2013).
[3] R.J. Gummow, M.M. Thackeray, W.I.F. David, and S. Hull, Mater. Res. Bull., 27, 327 (1992).
[4] E. Lee, J. Blauwkamp, F.C. Castro, J. Wu, V.P. Dravid, P. Yan, C. Wang, S. Kim, C. Wolverton, R. Benedek, F. Dogan, J.S. Park, J.R. Croy, and M.M. Thackeray, ACS Appl. Mater. Inter., 8, 27720 (2016).
Analysis of Iron Oxide Powder Formation By Hydrothermal Method through a Statistical Experimental Design and Evaluation of Its Use As Anodes for Libs
Authors: Gülcan Feryat , Karahan Billur Deniz 
Published: February 2020

It is known that size and shape are one of the important topics to be considered when to design electrodes for lithium ion batteries. Recently considerable attention has been paid to transitional metal oxide anodes, especially iron oxides due to their environmentally benign behavior and high theoretical capacities (>1000 mAh/g).
Therefore, in this work, 4 differently structured iron oxide nanoparticles have been synthesized via hydrothermal method, following the Taguchi experimental design. The effects of experimental parameters (precursor solution’s concentration, temperature and autoclave filling ratio) on the powder morphology have been examined by scanning electron microscopy analysis. Then, the structure of the powders have been characterized by X-ray diffraction method. And finally the electrochemical performances of these powders as anode material for lithium ion batteries have been done based on the galvanostatic test results (with 50mA/g rate, between 1mV-3V).
The results have shown that all samples performed higher initial discharge capacities than graphite. Whilst, all of them revealed low initial coulombic efficiencies, independent of their morphological and structural particularities. It is believed that although small size leads high contact area resulting improvement in the electrochemical performance of the electrode; the electronic conductivity of the sample should be improved to further ameliorate the electrode performance.
New 2.1 V Lithium- Ion Battery with Sulfurized Polyacrylonitrile (SPAN) Anode and LiMn2O4 Cathode
Authors: Berhe Gebregziabehr Brhane , Su Wei-Nien , Hwang Bing-Joe 
Published: February 2020

Sulfur/polyacrylonitrile (SPAN) composites are demonstrated as one of the interesting anode materials for lithium ion battery due to its high theoretical capacity, low cost and environmental friendliness. Herein, we investigated the electrochemical properties of SPAN composite as the anode material and LiMn2O4 (LMO) cathode for sulfur-lithium ion battery in carbonate based electrolyte for the first time. Sulfur as an anode coupled with a lithium-ion intercalation cathode creates a unique Li-ion/sulfur chemistry, realizing the highest energy density ever achieved, along with high safety and excellent cycle-life. The cell delivered a reversible discharge capacity of 1378.16 mAh/g at 0.1 C with specific capacity retention of 90.86% after 150 cycles. At 1 C, the capacity retention was 807.96 mAh/g after 400 cycles with an average decay rate of 0.7 mAh/cycle and average columbic efficiency of 99.5 % and its rate capability delivers a highly reversible capacity of 868.27 mAh/g at 2 C. The full SPAN/LMO cell is able to deliver a record high energy density of 185 Wh/kg (total electrode mass) and a power density of 270 W/kg (total electrode mass) at 1 C within the voltage ranging from 1 to 3.2 V. This new type of batteries surpasses current lead acid or VRLA batteries in gravimetric energy density four times. The capacity fading at 55 ℃ is mainly caused by the deposition of manganese on SPAN anode as XPS result confirmed. However, shuttling manganese was not observed when the cell was cycled at 25 o C. This strategy can be applied for other sulfur composite to provide a route for the development of high performance, cost effective and environmental benignity lithium ion based rechargeable batteries and the demonstrated cell with high rate and high capacity opens up new application opportunities for various electrical energy storage.
Keyword: - non-aqueous sulfur battery; SPAN composite; high capacity; energy storage