bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Role of Long Lifetime Li-Ion Cells in a Sustainable Future
Authors: Eldesoky Ahmed , Kowalski Nicholas , Logan Eric R , Aiken Connor P , Bauer Michael , Harlow Jessie , Dahn Jeff R. 
Published: November 2022

State-of-the-art Li-ion cells can have decades of lifetime (>40 years) and tremendous cycle life greater than 10000 cycles1. Such incredible cells greatly exceed the goal of 80% capacity retention after 800 cycles, promoted by some as sufficient for electric vehicles (EVs). However, by 2030 it is projected that more than 90% of all Li-ion batteries will be used to power vehicles2, with very few remaining for energy storage from intermittent renewables which must displace fossil fuels for power generation. The batteries in electric vehicles will represent a vast amount of energy storage capacity, which can be harnessed using vehicle to grid (V2G) technology. Batteries with that can maintain 80% of their capacity after a mere 800 cycles are unsustainable since most of the charge-discharge cycles in V2G will occur when the EV is stationary. For this reason, ultra-long-lived cells are a critical component of a sustainable future.
In this talk, we will discuss the important role of graphite material and upper cut-off voltage (UCV) on the lifetime of NMC811 cells, and how avoiding volume contraction in Ni-rich materials yields cells that should be eminently suitable V2G applications3,4. Additionally, we will discuss the results of a two-year study on the impact of C-rate, depth of discharge (DoD), UCV, and temperature on the lifetime of NMC811 cells. Finally, we will demonstrate that NMC cells with a low UCV, with an emphasis on Ni-rich materials, yield greater energy throughput compared to their higher energy counterparts due to their prolonged lifetime. The $/kWh metric is surely important when selecting a battery technology, but the levelized cost of energy over the battery lifetime is more important when batteries last for many decades.

References

Harlow, J. E. et al. A Wide Range of Testing Results on an Excellent Lithium-Ion Cell Chemistry to be used as Benchmarks for New Battery Technologies. Journal of The Electrochemical Society
166, A3031–A3044 (2019).

Pillot, C. The Rechargeable Battery Market and Main Trends 2018-2030. https://rechargebatteries.org/wp-content/uploads/2019/02/Keynote_2_AVICENNE_Christophe-Pillot.pdf (2019).

Eldesoky, A. et al. Impact of Graphite Materials on the Lifetime of NMC811/Graphite Pouch Cells: Part I. Material Properties, ARC Safety Tests, Gas Generation, and Room Temperature Cycling. Journal of The Electrochemical Society
168, 110543 (2021).

Eldesoky, A. et al. Impact of Graphite Materials on the Lifetime of NMC811/Graphite Pouch Cells: Part II. Long-Term Cycling, Stack Pressure Growth, Isothermal Microcalorimetry, and Lifetime Projection. Journal of The Electrochemical Society
169, 010501 (2022).
Design of High-Performance Solid Electrolytes Guided By Crystal Structure Characterization and Understanding
Authors: Liu Zhantao , Liu Jue , Mo Yifei , Chen Hailong 
Published: November 2022

Solid electrolyte is the key component in all-solid-state-batteries that is currently limiting the commercialization of this technology. An ideal solid electrolyte should have high room temperature ionic conductivity, low electronic conductivity, good compatibility with both cathode and anode, good mechanical properties, high air and moisture stability and low manufacture cost. Among these requirements, the improvement of ionic conductivity is prioritized as the conductivity of most existing solid electrolyte is still much lower than that of conventional liquid electrolyte.
The improvement of ionic conductivity and design and development of solid electrolyte materials are closely related to our understanding on the ionic diffusion mechanism in solids and the structure-property relationship. We believe that rational design of high-performance solid electrolyte should start from careful characterization and good understanding of the crystal structure. Here we report the crystal structure characterization on sulfides and halide solid electrolytes and the design and development of novel solid electrolytes based on our findings in structural characterizations. Ex situ high resolution synchrotron X-ray and neutron diffraction and pair distribution function analysis are used to understand the crystal structures in great details. In situ X-ray diffraction for different synthesis methods is coupled with variable temperature electrochemical impedance spectroscopy to understand the structure-property relationship in the solid electrolytes. The design, synthesis and electrochemical evaluation of several solid electrolytes will be presented and discussed.
Understanding Mechanisms of Ethylene Carbonate Gassing and Gas-Reducing Additives Using Isotopically Labeled Solvents
Authors: Kerber Brian M , Guillot Sarah Lucienne , Johnson Tobias , Peña-Hueso Adrián , Zhou Liu (Amy) , Du Peng , Usrey Monica Lee 
Published: November 2022

Gas generation during Li-ion battery operation remains a problem that can affect both safety and operational lifetime of the battery. Electrolyte solvents are a key source of gas generation1 and while gas-reducing additives have been identified, the underlying mechanisms require more study to fully understand the role between solvent structure and gas generation. Understanding of these gassing mechanisms can lead to optimized electrolyte systems with reduced gassing for the next generation of Li-ion batteries. Previous studies in the literature2 have detailed the use of 13C-labeled EC and DEC to identify the proportions of CO2 and CO that are derived from solvent sources, which in turn can help inform mechanistic understanding on gas generation in Li-Ion Batteries.
As previously studied by Silatronix®, electrolytes containing organosilicon (OS) materials show significantly reduced gas generation during high temperature storage and cycling in pouch cells primarily through CO2 reduction.3 Studies utilizing simple carbonate blends indicated that EC was the primary source of CO2; therefore, it was hypothesized that OS materials reduce gassing by preventing EC decomposition during high temperature testing. In this work, 13C-labeling was used to identify the sources of gas species in ternary carbonate electrolytes after both first charge (SEI formation4) and high temperature storage (extended aging) to allow the effects of electrolyte additives gas reduction to be elucidated.
Gas component analysis was performed using a calibrated GC-MS, providing identification and quantification of each gas species (labeled and unlabeled). These data give insight into how the labeled carbonate solvent may decompose into the observed gas phase products during the first charge (i.e., during SEI layer formation) and high temperature storage. Ethylene carbonate (EC) is found to be the primary source of ethylene generation, as well as a significant source of CO2 and CO. With the addition of OS, the most notable effect is that the previously seen reduction in all gas components is due to not only reduction of EC-related sources, but reduction in non-EC gas sources as well.

1 Rowden, B.; Garcia-Araez, N., A Review of Gas Evolution in Lithium-Ion Batteries. Energy Rep. 2020, 6, 10-18.

2Onuki, M.; Kinoshita, S.; Sakata, Y.; Yanagidate, M.; Otake, Y.; Ue, M.; Deguchi, M., Identification of the Source of Evolved Gas in Li-Ion Batteries using 13C-labeled Solvents. Journal of the Electrochemical Society
2008, 155, A794.

3 Guillot, S.L.; Usrey, M.; Peña-Hueso, A.; Kerber, B.; Zhou, L.; Du, P.; Johnson, T., Reduced Gassing In Lithium Ion Batteries With Organosilicon Additives. Journal of the Electrochemical Society
2021, 168, 030533.

4 Ktristiina Heiskanen, S.; Kim, J.; Lucht, B., Generation and Evolution of the Solid Electroyte Interphase of Li-Ion Batteries. Joule
2019, Volume 3 Issue 10, 2322.
Silicon/Carbon Composite Anode Materials for Li-Ion Batteries from a Scalable and Continuous One-Step Gas Phase Process
Authors: Loewenich Moritz , Orthner Hans , Wiggers Hartmut 
Published: November 2022

Silicon as an anode material has been intensively studied in academia, yet issues correlated to the vast volume change still hinder application in industry greater than a few mass percent. Some approaches reported can suppress the rapid capacity fade, which is observed for pristine silicon powders. However, they are usually based on complex processes or involve expansive chemicals, making them less interesting for commercial applications. Our approach focuses on the production of a long-term stable, silicon-based composite material in a single, easy-to-scale manufacturing process in a free-space reactor.
The newly developed composite consists of a silicon/carbon nanomaterial with a carbon-rich surface produced in a single-step gas phase process with production rates of already 100 – 500 g/h on the lab scale. Carbon is used as a composite component for two reasons: i) The incorporation of carbon in the range of 3-12 wt.% inhibits the formation of crystalline silicon within the silicon/carbon composites by disturbing the silicon-lattice, effectively preventing the formation of detrimental c-Li15Si4 phase during lithiation. ii) Furthermore, the carbon containing materials are less sensitive to oxidation and show enhanced cycling stability compared to pure silicon materials. By adjusting the process parameters, e.g. primary particle size d50,number can be tuned in the range of 40-120 nm. The electrochemical performance of the composite materials has been analyzed in half cells. For 75 wt.% active material electrodes, 90 % first cycle Coulombic efficiency and 75 % capacity retention after 200 cycles with an CCCV protocol at 0.5 C can be realized.

Figure 1
An Aqueous Binary Binder for Silicon-Based Electrodes
Authors: Zhou Bingyao , Mathew Kevin , Wang Guanyi , Xiong Jie , Yang Jian , Wu Qingliu , Lu Wenquan 
Published: November 2022

The relatively low coulombic efficiency (CE), especially the high initial capacity loss (ICL), and short cycle life are two major obstacles limit the wide adoption of Si-based materials as anodes of commercial lithium-ion batteries (LIBs). In this work, we introduced an aqueous binary binder composed of polyacrylic acid (PAA) and a water-soluble polymer to a Si-based electrode. Used as anodes of LIBs, the Si-based electrodes with the binary binder exhibited lower ICL and longer cycle life than those with PAA binder. The improved battery performance is ascribed to the unique electrode structure with the binary binder. The analysis from Fourier-transform infrared spectroscopy (FTIR) reveals that the intermolecular hydrogen bonds has been formed between PAA and the new polymer. The formation of hydrogen bonds could affect the properties of slurry for electrode coating and the structure of dried electrodes. Compared to the PAA binder, the new binary binder increases the viscosity of aqueous slurries at low shear rates and prompts the shear thinning, which benefit the preparation of slurries with high stability. Observations from the electron microscopy reveal that a relative porous structure was generated in the electrodes with the binary binder, compared with those with PAA binder. The porous structure could not only facilitate the electrolyte transport, but also accommodate the large volume expansion of Si during the charge/discharge processes. In addition, a thin solid-electrolyte-interface (SEI) film was found at the surface of cycled electrodes with the binary binder.
Key words: aqueous binder coulombic efficiency Si-based anode lithium-ion battery
Novel Approaches for High Efficiency Electrochemical Energy Storage Devices Based on DNAs and Nanomaterials
Authors: Bae JoonHo , Li Man , Li Yang 
Published: November 2022

In this talk, we present our approaches to realize high efficiency, high performance, next generation electrochemical energy storage devices based on DNAs and various nanomaterials. Firstly, novel electrochemical, battery-like capacitors using DNA-wrapped MWCNTs (denoted as CNT@DNA) as electrode materials are demonstrated. By using CNT@DNA, which were successfully assembled through a facial sonication treatment,. as template, a NiCo2O4 nanoparticle-anchored composite NiCo2O4-CNT@DNA was fabricated through situ precipitation coating process. Subsequently, the NiCo2O4-CNT@DNA and NiCo2O4-CNT (prepared without DNA) were used as the cathode materials to fabricate supercapacitors with high capacitive performance. The result of electrochemical test shows a high specific capacitance of NiCo2O4-CNT@DNA electrode of 760.0 F/g at 5 mV/s, which is higher than that of NiCo2O4-CNT electrode. The cycling performance of the NiCo2O4-CNT@DNA electrode displays a capacitance retention of 96.2% after 5000 cycles at the current density of 5 A/g. The above results demonstrate that the novel NiCo2O4-CNT@DNA composites can be desirable electrode materials for high performance supercapacitors in the future.
We also present our group's recent works on use of DNAs for advanced batteries including Li- S batteries and hybrid supercapacitors.
A New Approach to Mitigate the Deterioration of Ni-Rich Cathode Materials: Electrolyte Exposure Time
Authors: Park Nam-Yung , Sun Yang-Kook 
Published: November 2022

With the prevalence of electric vehicles, Ni-rich layered cathodes have been extensively developed to increase the energy density of Li-ion batteries (LIBs). However, cathodes with a high Ni content suffer from inherent structural and chemical instabilities, which lead to rapid capacity fading and thermal instability.1 In particular, the rapid capacity fading of Ni-rich layered cathodes is largely caused by microcracking and the resultant microstructural instability.2 In addition to microcracking, the time during which highly reactive Ni4+ ions are exposed to the electrolyte when the cathode is in a highly charged state also affects the deterioration of the cathode. Although the exposure time is not significant for cathodes with Ni contents of <60%, the calendar aging test of Ni-rich cathodes reveals that the exposure time, especially at high SoCs, critically affects the degradation of these high-Ni cathodes, as the internal surfaces of the particles are also exposed to the electrolyte via the microcracks.3 The exposure time is particularly pertinent for electric vehicle (EV) LIBs, as they remain stationary for long periods in the highly charged state and are operated intermittently. Consequently, the upper SoC limit of EV LIBs is commonly limited to ≈85%, but this limits the driving range and increases the cost of the batteries. Therefore, a holistic approach considering real-use behavior, as well as the properties of the material itself, is needed to overcome the limitations of Ni-rich cathodes.
Here, 1 mol% B doping of a core–shell concentration gradient (CSG) Li[Ni0.88Co0.10Al0.02]O2 cathode (CSG-NCA88) is shown to dramatically alter the microstructure of the cathode and effectively protect the particle interior from parasitic electrolyte attack. The B-doped CSG-NCA88 cathode, CSG-NCAB87, maintains its original microstructure even after holding for 500 h in the fully charged state, whereas irreversible structural damage occurs in the pristine CSG-NCA88 cathode during the prolonged electrolyte exposure. The long-term cycling results confirm that the capacity retention of the cathodes is determined by the electrolyte exposure time at a high SoC and that microstructural modification can effectively suppress the time-dependent degradation from electrolyte attack. The proposed CSG-NCAB87 cathode can be utilized at full capacity without restricting the SoC, thus realizing the development of economical high-energy-density LIBs.

Reference
s
:

[1] H.-J. Noh, S. Youn, C. S. Yoon, Y.-K. Sun, J. Power Sources, 2013, 233, 121.
[2] H.-H. Ryu, K.-J. Park, C. S. Yoon, Y.-K. Sun, Chem. Mater. 2018, 30, 1155.
[3] H.-H. Ryu, G.-T. Park, C. S. Yoon, Y.-K. Sun, Small, 2018, 14, 1803179.
Study on the Structural Degradation of the Polyaniline(PANi) Coated LiNi0.90Co0.85Mn0.15o Particles
Authors: Yoon Yeowon , Shin Seoyoon , Shin Moo Whan 
Published: November 2022

The nickel content of the layered lithium transition metal oxide cathodes is proportional to the discharge capacity of energy storage systems. Ni2+ ion, the oxidation state of Ni, moves to the Li sites when Li+ ion is deintercalated during discharge process due to the similar size of ion (Ni2+: 0.069 nm, Li+: 0.076 nm). The spatial transition of Ni2+ ion causes gradual cation mixing and structure degradation of cathode, resulting in the failure of the battery. Also, thick cathode-electrolyte interphase (CEI) is formed on the cathode surface because of the transition metal dissolution, the degradation of electrolyte, and the residual gas such as H2O and CO2.
Coating technology is one of the strategies for the physical protection of the cathode surface and the control of CEI layer thickness. Polyaniline(PANi) is a conductive polymer with stable oxidation state. PANi can enhance the electrochemical property and structural stability as a protective layer. In this study, we synthesized PANi material by the oxidative polymereization and coated NCM with the synthesized PANi by sonication method.
The PANi-coated NCM(PANi@NCM) has uniform coating layer with 5 nm thickness. PANi@NCM exhibits an initial discharge capacity of 208 mAhg-1 and a capacity retention of 81% after 50 cycles at 45 oC in Figure 1(a) and (b). After the cycling test, pristine and coated cathodes were disassembled for the comparison of the microstructure. Pristine NCM only shows the structural transition from layered structure to structure in the XRD pattern of Figure 1(c). Cross-sectional SEM image of the pristine NCM after cycling test shows micro and macro cracks are distributed from the bulk to the surface of the cathode as shown in Figure 1(d). On the other side, cracks are barely observed on the PANi@NCM particles in Figure 1(e). The layered structure of PANi@NCM is maintained even after cycling test, which are confirmed by TEM analysis with FFT patterns and HAADF images. Figure (f) and (g) show the FFT pattern of the two cathode surfaces after cycling test. Mixed phase is observed on the pristine cathode surface, while the layered structure is maintained on the PANi@NCM surface. Also, the PANi@NCM maintains a thinner passivation layer compared with that of the pristine NCM (6 nm vs 35 nm). In conclusion, the PANi coating layer prevents the degradation of structure and the formation of thick CEI layer. The structural stability enhances the electrochemical performance.

Figure 1
Chemically and Microstructurally Tailored Concentration Gradient Layered Cathode for Advanced Li-Ion Batteries
Authors: Park Geon-Tae , Kim Myoung-Chan , Sun Yang-Kook 
Published: November 2022

The recharging capability of Ni-rich layered cathodes deteriorates rapidly upon cycling, mainly from mechanical instability caused by removing a large amount of Li ions from the host structure.1,2 The resulting microcracks expose the cathode particle interior to electrolyte attack in addition to undermining the mechanical integrity of the cathode particle. In this study, we develop a Ni-rich layered cathode by combining precursor engineering and a new doping strategy during lithiation that generates minimal microcracking and exhibits substantially improved cycling stability. Excess Al is deliberately introduced into a concentration-gradient (CG) hydroxide precursor, which exhibits a highly oriented geometry in which elongated primary particles are aligned in the radial direction of a spherical secondary particles. The excess Al ions enable the refinement of the primary particles in a controlled manner and the precise tailoring of their morphology and orientation. It is demonstrated that the chemical and microstructural engineering of a Li[NixCoyAl1–x–y]O2 (NCA) cathode starting from its precursor stage produces a unique structure that relieves the detrimental mechanical strain and significantly extends the battery life. Thus, the designed CG Li[Ni0.86Co0.1Al0.04]O2 retains 86.5% of the initial capacity after 2000 cycles and an unprecedented 78.0% even at a severe operation condition of 45 oC. The proposed CG Li[Ni0.86Co0.1Al0.04]O2 represents a new class of Ni-rich NCA cathodes that can meet the energy density required for next-generation electric vehicles, without compromising the battery life and safety.

Reference
s
:

[1] S. Watanabe, M. Kinoshita, T. Hosokawa, K. Morigaki, K. Nakura, J. Power Sources 258 (2014) 210–217.
[2] H.-H. Ryu, K.-J. Park, C. S. Yoon, Y.-K. Sun, Chem. Mater. 30 (2018) 1155–1163.
(Invited) III-Oxide/III-Nitride Heterostructures for Power Electronics and Optoelectronics Applications
Authors: Fu Houqiang 
Published: November 2022

Due to their large bandgap, high critical electric field, and availability of high-quality large-size melt-grown bulk substrates, III-oxides including Ga2O3, Al2O3, In2O3, and their alloys have been extensively investigated for a myriad of electronic and optoelectronic applications. Recently, β-Ga2O3 based power electronics, RF transistors, and ultraviolet (UV) photodetectors have been demonstrated with promising performance. However, p-type β-Ga2O3 is still elusive due to high dopant activation energy (>1 eV), large hole effective mass, and hole trapping. This significantly limits the design freedom for β-Ga2O3 devices. Other p-type semiconductors have been proposed to form heterostructures with β-Ga2O3 such as p-NiO, p-Cu2O, and p-type III-nitrides. As popular wide bandgap semiconductors, III-nitrides are promising candidates to form III-oxide/III-nitride heterostructures to enable advanced device structures and new functionalities. Furthermore, III-oxides and III-nitrides can be epitaxially grown on each other with small lattice mismatch (< 5% for GaN and β-Ga2O3) by the industrial standard epitaxial method MOCVD. For example, vertical GaN violet LEDs grown on n-type β-Ga2O3 substrates have been reported. This talk will present our recent work on III-oxide/III-nitride heterostructures in power electronics and optoelectronics.
For power electronics, β-Ga2O3/GaN p-n heterojunctions will first be discussed. The heterojunction via mechanical exfoliation shows decent forward rectifying behaviors and thermal stability up to 200 °C but relatively low breakdown voltages (BV). To improve the breakdown capability, we carried out a comprehensive TCAD simulation study to design mesa edge termination for kV-class β-Ga2O3/GaN p-n heterojunctions. It was found that the electric field crowding effect is the main reason for the low BV. Several mesa edge termination structures were investigated such as deeply-etched mesa, step mesa, and p-GaN guard ring. Second, normally-off AlN/β-Ga2O3 field-effect transistors using polarization-induced doping will be discussed. A large two-dimensional electron gas is formed at the AlN/β-Ga2O3 interface due to polarization effects, and p-GaN gate is used to realize tunable positive threshold voltage. The device transfer and output characteristics with different device structures are also studied. For optoelectronics applications, self-powered spectrally distinctive Ga2O3/GaN heterojunction UV photodetectors grown by MOCVD will be discussed. Opposite current polarities are observed under different illumination wavelengths due to different carrier transports, which can be utilized to distinguish different spectra. These results indicate that (ultra)wide bandgap III-oxide/III-nitride heterostructures are a promising platform to enable new device structures and functionalities.