bluuebunny/crossref_metadata_2025 huggingface dataset:
Approaches to Improve Both Cycle and Calendar Life of Silicon-Based Lithium-Ion Batteries
Authors: Kim Ju-Myung , Jin Dahee , Cao Xia , Zhang Ji-Guang
Published: December 2024

During the last few decades, silicon (Si) has been extensively investigated as the next generation of anode material for lithium (Li)-ion batteries (LIBs) due to its high theoretical capacity (~ 4200 mAh g−1) which is more than ten times larger than those of graphite anode materials. However, because of the huge volume changes (~ 300%) of Si during repeated lithiation and delithiation, its lower electrical conductivity, inconsistent kinetics reaction, and relatively low initial Coulombic efficiency (ICE), large-scale application of Si-based LIBs (Si-LIBs) is still limited. The abovementioned intrinsic characteristics of Si trigger the short cycle life of Si-LIBs due to several reasons: 1) pulverization of Si particles; 2) Increasing cell impedance associated with continuous growth of solid electrolyte interphases (SEI) layers, 3) Poor structural integrity of the electrodes. In addition, the calendar life of Si-LIBs is still less than two years, which is far less than the ten-year calendar life required for electric vehicle applications. To improve both cycle life and calendar life, we have developed a low-cost, pitch-based carbon coating approach to synthesize micron-sized porous Si particles. A novel etching method is also developed to prevent overheating and bubbling during the Si etching process. Recently, we have developed a novel electrolyte based on the concept of localized high concentration electrolyte tailored for Si-LIBs. It leads to the formation of stable interphase layers on both the anode and cathode and effectively blocks the crosstalk between the electrodes, minimizing the impedance increase of Si||LiNi0.6Mn0.2Co0.2 (NMC622) batteries during storage at elevated temperature (55°C), therefore largely improves their calendar life. Si||NMC622 batteries using this electrolyte also demonstrated high-capacity retention of 92.4% after 500 cycles at 45°C with well-preserved electrode structures. More details on the development of Si-LIBs in PNNL will be presented in this talk.
Li-O2 Battery Cathodes with Partially Saturated Electrolyte
Authors: Li Xianglin
Published: December 2024

Lithium-oxygen batteries have attracted significant attention recently due to their high theoretical energy densities. As an open system, the battery breathes oxygen from the air to complete the oxygen reduction reaction (ORR) and release oxygen to the environment during the oxygen evolution reaction (OER). As a result, the saturation of liquid electrolytes in the positive electrode, where ORR and OER occur, can strongly affect the Li-O2 battery performance. However, it has not been clear to what extent saturation reduction can impact battery capacity. Therefore, in this study, we investigated the influence of electrolyte saturation and distribution on deep discharge/charge capacity and cycling stability. The study used both models and experiments to investigate the electrolyte distribution, double-layer capacitance, and electrolyte resistance within the porous cathode at different saturation levels. Results revealed that electrodes with 60% electrolyte saturation could achieve almost the same maximum deep discharge (5.6% lower) and charge (2.3% lower) capacities with fully saturated electrodes. Electrodes with 60% saturation had the highest energy density, 247.13 Wh/kg. Partially wet cathodes with 60% and 40% saturations could obtain similar numbers of cycles or even more cycles than those with 100% saturation. However, fully wet cathodes had the most stable cycling regarding charging efficiency and the lowest overpotential between discharge and charge (1.31V-1.39V). The measured electrochemically active surface areas showed that even 40% saturation could sufficiently wet the cathode surface and obtain a double layer capacity (14.86 mF/cm2) similar to 100% saturation (15.64 mF/cm2).
Industry-Level Safety Enhancement of High-Energy Li-Ion Batteries Via Material-Level Surface Modification
Authors: Chang Shu Jui , Chen Hsi , Wu Nae-Lih (Nick)
Published: December 2024

Developing high-energy-density lithium-ion batteries (LIBs) to meet the needs of electric vehicles (EVs) and sustainable energy storage applications brings more safety issues simultaneously.

On the anode side, graphite has the advantages of a high abundance and low lithiation electrochemical potential, which reduces the cost of LIBs and brings higher energy. However, graphite is vulnerable to the plating of metallic Li dendrite, which could easily arise from over-lithiation due to heterogeneity in the anode electrode or fast charging. Li dendritic deposits could penetrate through the separator to trigger cell short-circuit and eventually thermal runaway. On the cathode side, the Ni-rich layered oxide cathodes' high surface reactivity and low oxygen lattice stability lower the thermal stability. Moreover, it is easy to release oxygen during the charging and discharging, providing the negative electrode with abundant combustion accelerant and accelerating thermal runaway.

An effective and efficient strategy to mitigate the abovementioned problems is to apply an artificial solid-electrolyte-interphase (A-SEI) coating on both the anode and cathode to alleviate the surface-side reactions. This study focuses on enhancing the safety of LIB full cells by modifying the properties and stability of the SEI on the anode and cathode electrodes. A polymeric artificial SEI coating for the anode improves electrode performance and effectively suppresses native SEI and Lithium dendrite formation. Meanwhile, a composite coating for the cathode simultaneously enhances cycle stability and thermal stability due to the altered thermal decomposition pathway of an NCM811 cathode. In this study, we will explain the electrochemical performance of using artificial SEI and the prevention mechanism of thermal runaways and verify the high safety of the modified full cells through nail penetration testing.
Impact of Temperature on the Diffusion in Silicon-Based Anodes
Authors: Böhm Kevin , Markus Torsten , Henriques David
Published: December 2024

Kems4Bats, established within the BMBF framework NanoMatFutur at Hochschule Mannheim, focuses on understanding heat and gas evolution in Li-ion batteries through advanced experimental methods. The group integrates thermodynamic data and new insights into phenomena like diffusion, solid electrolyte interface formation, aging from high-power charging, and thermal runaway. A state-of-the-art laboratory with cutting-edge equipment allows detailed study of materials properties affecting diffusion coefficients and heat and gas evolution, such as electrode composition and particle size. Key achievements include setting up a battery production line and developing a novel device, KEMS (Knudsen-Effusion Mass-Spectrometry), for vapor pressure measurements, enhancing battery safety and performance.

Building on the experimental capabilities and insights gained by the Kems4Bats group, our research also zeroes in on specific materials that hold promise for enhancing battery performance. Among these, silicon stands out due to its high theoretical capacity, making it an ideal candidate for the next generation of anode materials in lithium-ion batteries. However, despite its potential, certain thermodynamic properties of silicon remain inadequately explored, notably diffusion. Diffusion is crucial as it facilitates the transport of ions to the active material's surface, essential for lithiation. This process is influenced by various factors including the state of charge (SOC) and cell temperature.

This study explores the impact of temperature on the diffusion coefficient of self-made silicon anodes, composed of nanoparticles mixed with carbon black. The weight ratio between the anode components is 45/45/10 (Si/CB/CMC). PAT-Cells are used to assemble half-cells with a lithium-counter electrode. The half-cells, organized into four groups of at least three cells each, are examined at different temperatures (15°C, 25°C, 40°C, and 60°C) post-formation. The diffusion coefficient is determined via the galvanostatic incremental titration technique (GITT). Furthermore, incremental capacity analysis (ICA) is conducted to determine the impact of phase changes in the active material on the coefficient and to show the impact of temperature on the anodes' capacity.

In summary, our investigation provides crucial insights into the temperature-dependent behavior of the diffusion coefficient in silicon anodes, a key component for enhancing lithium-ion battery performance. By analyzing the effects of temperature on both the diffusion process and phase changes within silicon-carbon black composite anodes, this study underscores the significant influence of thermal conditions on the efficiency and capacity of next-generation battery technologies. These findings not only contribute to a deeper understanding of silicon anodes' operational dynamics but also highlight the critical role of temperature management in optimizing lithium-ion battery performance.
Fluoroalcohol Additives That Modify the Nature of Solid Electrolyte Interphase and Cathode Electrolyte Interphase Selected By Machine Learning Approach
Authors: Nakamoto Mitsunori , Umezu Satoshi , Kumita Hideyuki
Published: December 2024

Inclusion of silicon materials to the negative electrode is seen as a promising approach to realize high-capacity lithium-ion batteries. However, the cycle life of such batteries including silicon materials is limited. The importance of controlling the solid-electrolyte interphase (SEI) has been pointed out for the extended battery life. It has been reported that fluoroethylene carbonate (FEC) and vinylene carbonate (VC) extend the battery life by modifying the nature of SEI. Still, it is difficult to satisfy multiple requirements for commercial batteries (like storage stability and low resistance) with a single additive. Therefore, it is important to expand the options of additive species and to optimize the combination of additives.

In this study, a cell consisting of a Si/graphite composite negative electrode is considered, and we explored potential additive candidates that extend the battery life. Candidate additive molecules were selected by machine learning approach, where machine leant models was used for a screening withing a framework of Bayesian optimization that predict a capacity retention rate at a particular cycle be means of the molecular descriptors. In particular, we report a fluoroalcohol material, hexafluoroisopropanol (HFIP) as an additive that improves the cycle performance. Conventionally, the introduction of an alcohol material into the electrolyte has been regarded to promote the generation of hydrogen fluoride (HF) and result in the degradation of cell components such as electrolytes. However, our work found out that such degradation is suppressed when HFIP is included (Figure 1). To study electrochemical and chemical properties of the cell with HFIP, NCA||Si/graphite composite cells were fabricated, and cycle tests were carried out. Afterwards, the cells were dismantled, then the surface of positive and negative electrodes were investigated by XPS. Further characterization was conducted by NMR on the extracted electrolyte and the SEI rinsed individually from positive and negative electrodes. In this presentation, we report the relationship between (1) the chemical aspects of the electrolyte and SEI, and (2) the battery performance, and discuss the key factors that contribute to the improved cycle performance.

Figure 1
Bi-Dimensional PTFE Fibrillation Process Implemented in Solvent-Free Manufacturing of Ultra Thick Electrodes for Lithium-Ion Batteries
Authors: Shim Hyeong-Seok , Lee Sang Hyun , Lee Kwon-Hyung , Song Gyujin , Kim Tae-Hee
Published: December 2024

A method for manufacturing electrodes via a solvent-free dry process can dramatically increase the energy density of lithium-ion batteries (LIBs) without the use of toxic organic solvents. This innovative approach is a strong candidate for advanced battery technologies due to its environmental benefits and cost savings. However, ultra thick electrode required to achieve high energy density significantly intensifies the migration resistance (Rion) and charge transfer resistance (Rct) by longer diffusion length of lithium ions and electrons.

The fundamental solution proposed to solve this problem is to increase the conductive additives content to form the enhanced electronic conductivity networks. However, the higher the content of conductive additives in the electrode composition, the more binder is required. If the binder content is insufficient, the increased contact area and excessive agglomeration due to the high specific surface area of the conductive additives will result in reduced interparticle cohesion and uneven packing density. This hinders the formation of a continuous fiber matrix in the PTFE fibrillation process and consequently weakens the mechanical properties of the electrode.

In this study, the proposed bi-dimensional PTFE fibrillation process can be effectively utilized to form a uniform and efficient fiber matrix within electrodes, even at high conductive additives content (≥5 wt%) and low binder content (≤1 wt%). This process enables the electrodes to be stored and transported in roll form and preserves the structural integrity of the electrodes during mass production. Moreover, the high and uniform conductivity of the manufactured electrodes prevents significant increases in resistance, even with increased electrode thickness, thus enhancing the electrochemical performance of high energy density LIBs.
Plating Behavior and Charge Transfer Kinetics of the Amorphous-LLZO Modified Solid Electrolyte for Lithium Solid State Batteries
Authors: Kuo Rui-Tung , Lin Tzu-Ying
Published: December 2024

Charge-transfer kinetics between electrodes and electrolytes critically influence the stability of lithium solid-state batteries. Garnet-type Ta-doped Li7La3Zr2O12 (LLZTO) boasts a high ionic conductivity (up to 3 × 10–4 S cm–1) at room temperature and shows good stability with the lithium metal. To enhance the durability and overall performance of lithium solid-state batteries, the manipulation of lithium growth morphology during charge and discharge cycles emerges as a critical factor. Although numerous researchers have dedicated efforts to establishing better electrode-electrolyte adhesion, scant attention has been directed toward investigating the charge transfer kinetics amidst the morphological changes during lithium stripping and plating. Additionally, there is a lack of direct evidence supporting the modification of the electrode-electrolyte interface to enhance stripping-plating behavior.

This study undertook to fabricate metal electrodes by thermal evaporation and magnetron sputtering techniques onto LLZTO pellets. The subsequent analyses encompassing in-situ scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS) facilitated the real-time monitoring of these morphological and internal variations. In addition, we further manage to enhance the interface between electrode and electrolyte with amorphous Li7La3Zr2O12 (a-LLZO) thin film. The a-LLZO film was employed to impede the formation of lithium dendrites and possible current leakage under external energy applied. Since lithium ions are prone to transfer within grain boundaries, the amorphous thin films show great potential to be the solution. The potentiostatic and galvanostatic tests could further investigate the critical conditions for a-LLZO to protect the interface.

These findings have significant implications as they not only improve our understanding of the electroplating dynamics within lithium batteries but also represent a tangible advancement with thin-film materials. In essence, this work has the potential to significantly boost the development of lithium-based thin-film batteries to new heights.
Interrelation between External Pressure, SEI Structure and Electrodeposit Morphology in an Anode-Free Lithium Metal Battery
Authors: Mitlin David
Published: December 2024

We explore the interrelation between external pressure (0.1, 1, 10 MPa), solid electrolyte interphase (SEI) structure/morphology, and lithium metal plating/stripping behavior. To simulate anode-free lithium metal batteries (AF-LMBs) analysis was performed on “empty” Cu current collectors in standard carbonate electrolyte. Lower pressure promotes organic-rich SEI and macroscopically heterogeneous, filament-like Li electrodeposits interspersed with pores. Higher pressure promotes inorganic F-rich SEI with more uniform and denser Li film. A “seeding layer” of lithiated pristine graphene (pG@Cu) favors an anion-derived F-rich SEI and promotes uniform metal electrodeposition, enabling extended electrochemical stability at a lower pressure. State-of-the-art electrochemical performance is achieved at 1MPa: pG-enabled half-cell is stable after 300 hrs (50 cycles) at 1 mA cm-2 rate - 3 mAh cm-2 capacity (17.5 mm plated/stripped), with cycling Coulombic efficiency (CE) of 99.8%. AF-LMB cells with high mass loading NMC622 cathode (21 mg cm-2) undergo 200 cycles with a CE of 99.4% at C/5-charge and C/2-discharge (1C = 178 mAh/g). Density functional theory (DFT) highlights the differences in the adsorption energy of solvated-Li+ onto various crystal planes of Cu (100), (110), and (111), versus lithiated/delithiated (0001) graphene, giving insight regarding the role of support surface energetics in promoting SEI heterogeneity.
(Invited) Electrochemistry Based and Coupled Characterization of Electrode-Electrolyte Interfaces in Lithium Ion Batteries
Authors: Marschilok Amy C. , Takeuchi Esther S. , Takeuchi Kenneth J.
Published: December 2024

The function of lithium ion batteries is significantly impacted by the electrochemical cycling conditions, such as voltage window and cycling rate. Oxidation states of redox active centers and the chemistry and distribution of species at interfaces can change substantially during relaxation processes. Therefore there can be an inherent benefit for methods which enable characterization of the system within its operating environment, ideally during operation of the functioning battery. This presentation will highlight examples of insight gained from electrochemically based and coupled characterization of lithium ion battery systems. Complementary insight from interfacial methods and bulk approaches will be described.
(Invited) Enhancing Lithium Stripping Efficiency in Anode-Free Solid-State Batteries
Authors: Zhu Hongli
Published: December 2024

Anode free all-solid-state lithium metal batteries hold great promise for achieving high energy density and safety. However, they are plagued by low initial Coulombic efficiency and rapid capacity decay, which are particularly pronounced at high cathode loadings. Through the use of operando techniques, we determined that these issues stem from the loss of interfacial contact during the lithium stripping process. To tackle this challenge, we introduce a novel conductive carbon felt elastic layer that self-adjusts the pressure on the anode side, ensuring a consistent and stable contact between lithium and the solid electrolyte. This innovative layer serves a dual purpose by providing electronic conduction while simultaneously releasing the plating pressure. As a result of this modification, the first Coulombic efficiency exhibits a dramatic improvement, increasing from 58.4% to 83.7%. Moreover, the cycling stability is enhanced by more than 10 fold. In summary, this study presents a novel approach for boosting the performance and longevity of anode free ASLMBs. By mitigating the inefficiencies associated with lithium stripping through the implementation of a self-adjusting interfacial pressure enabled by a conductive elastic interlayer, we have demonstrated a significant advancement in ASLMB technology.
Facile Characterization of the Lithium Metal/Electrolyte Interface through Nonlinear Electrochemical Impedance Spectroscopy
Authors: Lee Rose Yesl , Liu Jun , Schwartz Daniel T.
Published: December 2024

Next-generation lithium metal batteries have demonstrated the high energy densities necessary for electric vehicles and thus have the potential to enable the widespread electrification of transportation.1 However, mass adaptation of lithium metal batteries is challenged by the unsatisfactory cycle life resulting from the lack of electrolytes compatible with the highly reactive lithium metal surface. The uncontrolled interactions between the lithium anode and the electrolyte results in the continuous depletion of both participants and/or the formation of electrically isolated lithium, which ultimately reduces the cycle life. While progress in electrolyte engineering offers hints on the role of the electrolyte in essential battery processes (eg., the formation of a stable solid-electrolyte interphase layer and favorable deposited lithium morphologies), further improvements in lithium metal batteries necessitates a deeper understanding of the lithium metal/electrolyte interface.

The performance of lithium metal battery electrolytes is often gauged by the ratio between the discharge and charge capacities, or the Coulombic efficiency (CE). An electrolyte with a high CE indicates that the discharge and charge capacities were nearly equal, or that very little lithium was lost to undesirable side processes during cycling. A typical CE experiment, such as the popular Aurbach method, involves several cycles of plating and stripping a lithium reservoir from a copper substrate at one current density.2 With hundreds of cycles, a single CE test can be time-consuming, presenting a bottleneck in electrolyte research.

Here, we integrate nonlinear electrochemical impedance spectroscopy (NLEIS) into a modified Aurbach method to evaluate the evolution of the lithium metal/electrolyte interface with cycling and detect earlier signs of lower CE electrolytes. With the same instrumentation as its linear counterpart, NLEIS utilizes a moderate AC current amplitude to elicit a weakly nonlinear voltage response that is sensitive to kinetic, transport, and thermodynamic processes. Notably, the second harmonic voltage response is formed by the differences between the battery electrodes, making NLEIS a powerful diagnostic tool for detecting subtle changes.3,4 This work introduces a methodology that could enable faster characterization of lithium metal electrolytes, yet opens the path for more in-depth kinetic studies.

G. M. Hobold et al., Nat. Energy, 6, 951–960 (2021).

B. D. Adams, J. Zheng, X. Ren, W. Xu, and J. G. Zhang, Adv. Energy Mater., 8, 1–11 (2018).

Y. Ji and D. T. Schwartz, J. Electrochem. Soc., 170, 123511 (2023).

4. Y. Ji and D. T. Schwartz, J. Electrochem. Soc., 171, 023504 (2024).

Figure 1
Surface Engineering of LiNi0.8Co0.1Mn0.1O2 By Ultrathin Al2O3 Via Atomic Layer Deposition
Authors: Byun Changwoo , Choi Yeongtae , KIM hee-Soo , Shin Seokyoon
Published: December 2024

Nickel-rich Li(NixCoyMn1-x-y)O2 (NCM) is considered one of the most promising cathode materials for next-generation high-energy lithium-ion batteries (LIBs). However, nickel-rich NCM suffers from short battery lifespan, poor rate performance, and structural instability during cycling due to side reactions between the cathode material and the electrolyte. To overcome the aforementioned problems, coating the surface of nickel-rich NCM powders is an efficient and straightforward strategy. In recent years, atomic layer deposition (ALD) has been gaining attention for its utility in preparing LIB electrode materials. Compared to traditional coating methods, ALD can form uniform and ultrathin coating layers, which protect the cathode from reactions with the electrolyte while maintaining electrical conductivity and fast electron transport. More importantly, this process is energy-efficient, rapid (taking only a few minutes), and does not damage the electrode. Nevertheless, attempts to directly deposit ALD coatings onto nickel-rich NCM composite electrodes to enhance the electrochemical performance of NCM have not been widely reported.

This study provides an efficient technique based on ALD to enhance the electrochemical performance of Ni-rich NCM cathode materials. The surface of the Li(Ni0.8Co0.1Mn0.1)O2 (NCM811) composite electrode was directly coated with a high-quality ultrathin layer of aluminum oxide (Al2O3). The thickness of the coating layer was precisely controlled at the sub-nanometer scale by the number of ALD cycles. It could protect the surface of the active NCM811 powder and maintain interparticle electron pathways, thereby enhancing electrochemical performance. The optimal thickness of the Al2O3 coating for maximizing the electrochemical performance of NCM811 was grown via 10 ALD cycles. The ALD-based ultrathin Al2O3 coating on the NCM811 was performed using a rotary ALD system. The morphology of the samples was confirmed using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Energy-dispersive X-ray spectroscopy (EDS) elemental mapping was collected in scanning transmission electron microscopy (STEM) mode. X-ray diffraction (XRD) patterns were collected using X-ray powder diffraction equipment. The chemical composition of the coating was analyzed using X-ray photoelectron spectroscopy (XPS) with Al Kα radiation. Cell testing was conducted using a coin-type half-cell with lithium metal as the anode.
Lithium Metal Batteries Using Lithiophilic Oxidative Interfacial Layer on the 3D Porous Metal Alloy Media
Authors: Choi Yusong , Lee Jaein , Ahn Tae-Young , Yoo Eunji , Yeo Jae-Seong
Published: December 2024

Numerous lithium-infused (or impregnated) metal anodes using pure nickel foams with excellent properties have been developed for use in Li batteries. However, pure Ni exhibits high reactivity with molten Li during infusion (e.g., coating, impregnation). Herein, a high-performance and ultra-stable (against molten Li) lithium-impregnated lithium metal anode (LI-LMA) is fabricated by simple oxidation of nickel alloy foam (NAF) at 900 °C in air. A symmetric cell test employing the LI-LMA showed stable stripping and plating performance. For comparison, a symmetric cell with pure Li was also discharged, demonstrating a continuously increasing polarization during stripping and plating. For a full cell performance test, LI-LMA and pure Li anodes are fabricated with NMC cathode and then cycled at 0.2 C. The full cell with LI-LMA and NMC outperforms the full cell with pure Li and NMC. Moreover, the full cell with LI-LMA and NMC shows stable cycle performance over 200 cycles with over 99% coulombic efficiency (pure Li and NMC full cell lasted less than 100 cycles). This significant performance improvement can be attributed to the high electroconductivity of the NAF and enhancement of the plating and stripping of Li ions by even charge distribution. After the cell discharge, the LI-LMA exhibited no Li dendrite. Given this advantageous fabrication method, in addition to its high cycle stability, LI-LMA is expected to aid in the development of lithium metal batteries (LMB) with enhanced performance.
Fabrications of Graphene Oxide and Silver Nanowire Hybrid Nanocomposites for Li-Metal Anodes with Dendrite Suppression
Authors: Won Sojeong , Yeom Bongjun
Published: December 2024

Lithium (Li) metal is the most promising anode material for Li-metal batteries due to its high theoretical capacity (3,860 mAh g-1) and low electrochemical potential (-3.04 V vs. the standard hydrogen electrode). However, many of previously studies for Li-metal batteries utilized a relatively thick ~ 50 μm Li metal foils, which lowers overall energy densities of the cells. Therefore, there have been growing research to reduce the thickness of the Li-metal anode to improve the energy density of batteries. Typical anode current collector of a copper foil show low affinity of Li metals with great initial deposition overpotentials when Li-metals are eletrodeposited. Such lithiophobicity accelerate the problems of Li dendritic growth with reduction in cycle life, which has been critical problems in practical applications of pristine Cu current collectors for Li-metal batteries. Therefore, various types of surface modification methods have been reported so far, such as coatings of carbon materials such as GO or metal-based materials such as Ag, Au. However, only carbon or metal modifications have been suffering from the relatively low lithiophilicity of the carbons and pulverizations of metals during cyclings by alloying and dealloying with Li-metals, respectively. Carbon and metal hybrid composites were also studied to mitigate these problems, but there still large rooms for further improvements showing unstable cycle performances at high C-rates.

Herein, we report the fabrication of lithiophilic graphene oxide (GO) and silver nanowire (AgNW) nanocomposite anodes by Layer-by-Layer (LbL) assembly methods for uniform Li depositions. GO provides a fast Li ion movement channel with high ionic conductivity, and AgNW shows low nucleation overpotential behavior due to the formation of an alloy with Li. Therefore, we alternately stack these two materials using the LbL assembly method to induce a synergistic effect of their advantages. The resulting GO and AgNW nanocomposite films show uniformly deposited morphology after Li depositions and low nucleation overpotential compared to copper foils when pre-deposited at capacity of 4 mAh cm-2. The symmetric cells with the GO-AgNW composite electrodes with 4 mAh cm-2 of Li pre-depositions show stable behavior for 400 cycles with an overpotential of 10 mV at 1 mA cm-2 and 1 mAh cm-2. In addition, the full cells using LFP cathode materials operate more than 400 cycles at 1 C-rate and 200 cycles even at high 3 C-rate, showing longer cycle life and capacity retention than copper foil. These LbL self-assembled anodes provides a facile route to prepare lithiophillic anode coatings that can be advantageous for the preparations of high energy density Li-metal batteries.
Combined Chemical and Heat Treatment of Graphite from Spent Zn-C Batteries for Li-Ion Batteries
Authors: Kasemchainan Jitti , Chinnakutti Karthik kumar , Yun Hojung , Saito Nagahiro
Published: December 2024

Lithium-ion batteries (LIBs) play a crucial role in the functioning of electric vehicles, portable gadgets, and grid storage systems. One of the primary obstacles presented by the growing demand for LIBs is the scarcity of raw materials required for their production. One economical strategy involves the use of graphite recovered from spent zinc-carbon (Zn-C) batteries as the negative electrode material. Recycling not only solves the environmental issues related to disposal of spent Zn-C batteries, but also leads to attaining inexpensive raw materials, value-adding the waste materials, and ultimately creating circular material utilization. In this work, a facile and applicable recycling procedure is proposed as the combination chemical and heat treatment of the recovered graphite. Firstly, the graphite is chemically treated with different concentrations (0.1, 1.0, and 10.0 M) of KOH under different temperatures (30, 60, and 90 ˚C). Then, the resulting graphite is neutralized and heated at different temperatures (700, 800, and 900 ˚C) under N2 or H2/N2 atmosphere. After microstructural characterizations of X-ray fluorescence (XRF), X-ray diffraction (XRD), Raman spectroscopy, Near Edge X-Ray Absorption Fine Structure spectroscopy (NEXAFS), X-ray photoemission spectroscopy (XPS), and Scanning electron microscopy (SEM), the best graphite samples in terms of crystallinity and purity are chosen for electrode preparation. The composite graphite electrodes are composed of the treated graphite, carbon black, and sodium alginate. Note that sodium alginate is a bio-based binder and can be dissolved in water, making the preparation process towards green direction. Li-ion battery half-cells containing the graphite electrodes, Li metal, and a standard electrolyte of 1 M LiPF6 in 1:1 v/v EC:DMC are subject to electrochemical characterizations, e.g. galvanostatic cycling, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) so as to investigate the battery performance and efficiency. The battery cells with the best-conditioned graphite are capable of delivering 300 mAh·g-1 at 0.1C for more than 100 cycles. Accordingly, this encourages a feasible recycling procedure of the waste materials for the upcoming battery industries in the foreseeable future.
(Invited) Overview and Outlook of Korea’s Battery Industry
Authors: YI Jeongdoo
Published: December 2024

Recently, various issues have been raised in the automobile battery market, and the starting point is the issue of core minerals through the US Inflation Reduction Act (IRA) and the use of recycled raw materials and materials through Europe's CRMA.

At the same time, battery technology is diversifying, with batteries using various materials such as iron phosphate as well as existing ternary batteries being installed in automobiles, and the development and application of sodium batteries have been reported, and research is actively underway. Additionally, research is being actively conducted on lithium metal batteries, all-solid-state batteries, and lithium sulfur batteries as future technologies that can significantly increase energy density.

We would like to discuss the current issues in batteries, the direction of technological development, and areas to focus on as anticipated by the Ministry of Trade, Industry and Energy, as well as response strategies and business directions.
Fabrication of Thin Li6PS5Cl Separators for All-Solid-State Lithium-Ion Batteries
Authors: Bardenhagen Ingo , Gockeln Michael , Schwenzel Julian
Published: December 2024

Thin sulfide separators for all-solid-state batteries are crucial to obtain low internal battery-cell resistances, i.e. good battery-cell performances, and high energy densities [1]. A two-dimensional sulfide separator sheet consists commonly of sulfide powder and a polymeric binder. The components are dispersed in a solvent and casted to a given sacrificial substrate. Current challenges for thin separator fabrication include either (1) high costs for commercial sulfide material with very fine particle sizes (<5 µm) or (2) very large particle size distributions (<1 to >100 µm) for “lower-cost” commercial sulfide powders. Since the separator thickness is limited to the diameters of the largest particles, sulfide particles are preferred to be smaller than ~5 µm at an affordable price.

In this work, we have produced thin two-dimensional sulfide separator sheets with thicknesses of 20 µm from commercial “lower-cost” Li6PS5Cl material. The powder was wet-ball-milled and dried before it was subjected to paste fabrication and separator casting. Using x-ray diffraction and electrochemical impedance spectroscopy, it was proven that crystal structure and Li-ion conductivities of Li6PS5Cl were unhampered from the mechanical treatment. Secondary electron images of the separator cross-sections revealed ultra-fine particles and the strikingly low separator thickness of 20 µm. An example for such a separator is visible in the attached figure: (a) Photograf of the casted layer on PET foil, (b) SEM top view, (c), cross-section (d) and magnified cross-section of a compressed separator.

In the next step, the separator was connected with the (composite) electrodes. Here, we investigated two different approaches to achieve a good mechanical contact and therefore a good electrochemical performance. On the one hand we transferred the separators onto the electrodes by uniaxially or isostatically pressuring. On the other hand we investigated a direct coating of the separator slurry onto metal or composite electrodes.

[1] Randau, S., Weber, D.A., Kötz, O. et al. Benchmarking the performance of all-solid-state lithium batteries. Nat Energy
5, 259–270 (2020). https://doi.org/10.1038/s41560-020-0565-1

Figure 1
Borohydride/Halide and Oxyhalide/Halide Composite Electrolytes for Assbs
Authors: Han JiHoon , Lee Young-Su , Cho Young Whan
Published: December 2024

New solid Li-ion conductors based on borohydride-halides and oxyhalide/halides composites have been synthesized by mechanochemical reaction. They include LiM(BH4)yX4-y (M = Y, Ce, X = Cl, Br), Li3M(BH4)yX6-y (M = Y, Sm, Er; X = Cl, Br), y LiMOCl4 + (1-y) LiMCl6 + (2y-1) LiCl (M = Nb, Ta; 0.5 < y <1), and LiMOCl4 + LiCl + y Li2O (M = Ta, Nb; 0 < y < 0.8). The kinetics of the mechanical reaction strongly depends on the selection of starting materials, particularly of oxides. The structures of these electrolytes have been analyzed by X-ray diffraction (XRD), Raman, solid-state nuclear magnetic resonance (NMR). The thermal stability has been tested by differential scanning calorimetry (DSC) and thermogravimetric analysis/mass spectrometry (TGA/MS). The basic mechanical properties have also been characterized by using a simple powder compression as well as nanoindentation, and the results compared with theoretical prediction. Depending on whether they are amorphous or crystalline phases, their ionic conductivity varied between 10-5 and 10-2 S/cm at room temperature. The effect of anion composition and the phase composition of the composites on the ionic conductivity has also been investigated by changing the mix ratio of starting materials; LiX and MX3 for LiM(BH4)yX4-y, and LiCl, MX5, M-O/Li-M-O for LiMCl6/LiMOCl4/LiCl and LiMOCl4/LiCl/Li2O composites. Chemical stability, electrochemical stability window, and critical current density have been characterized. Using these solid electrolytes, all solid state batteries have been assembled and the compatibility of the electrolyte with Li or In/Li anode and uncoated (or Nb-coated) NMC cathode, C-rate property, and long term charge/discharge cycle property have been investigated and the results will be presented.
Design of Poly(ethylene oxide)-Based Polymer-in-High Concentrated Ionic Liquid Electrolyte for All-Solid-State Lithium Metal Batteries
Authors: Zhang Mingjie , Pal Urbi , Azad Faezeh Makhlooghi , Kondou Shinji , O'Dell Luke , Elia Giuseppe A , Gerbaldi Claudio , Forsyth Maria
Published: December 2024

Solid polymer electrolytes (SPEs) have emerged as promising candidates for solid-state lithium metal batteries (LMBs) due to their inherent safety advantages and potential to facilitate high energy density devices [1]. Poly(ethylene oxide) (PEO) has been the most prominent representative polymer host in SPEs since 1970s because of their excellent ability to solvate Li ions and support ion transport [2,3]. However, it suffers from limited oxidation stability (<4 V vs. Li) and low ambient temperature conductivity (up to 10−6 S cm−1), thus hindering its practical application in high voltage (>4V) high energy density LMBs. In this study, a new type of polymer-in-“high concentrated ionic liquid” solid electrolyte is designed with high molecular weight PEO, N-propyl-N-methylpyrrolidinium bis(fuorosulfonyl) imide (C3mpyrFSI) ionic liquid and lithium bis(fluorosulfonyl)imide (LiFSI). The EO: [LiFSI/C3mpyrFSI] ratio has been widely varied and the resulting physicochemical and electrochemical properties have been explored. The optimal electrolyte provides promisingly high oxidative stability exceeding 5V and ambient temperature conductivity of 5.6 x10-4 S cm-1. It induces stable solid electrolyte interface with Li metal and demonstrates prolonged reversible Li plating-stripping in Li symmetrical cells even at high temperatures (up to 70°C). All solid-state Li metal cells assembled with LFP cathode show excellent rate capability and cycling performance (see Figure 1). The discharge capacity can be maintained at 47.3% when the current density increases 20 times from 0.1 C to 2 C (areal capacity ~0.4 mAh/cm2), and long-term cycling of Li||LFP cells showed 97% capacity retention after 100 cycles at 0.2 C. Based on the findings, an ion conduction network consisting of interconnected anion-rich clusters and pores is highlighted to help understand the structural change, ion dynamics and good battery performance of the designed SPE. Therefore, the novel approach of polymer-in-“high concentrated ionic liquid” solid electrolyte enables a new pathway to design high-performing SPEs for high energy density all-solid-state LMBs.

Figure 1
Comparative Analysis of Entropy-Assisted Garnet-Structured Electrolyte in Solid-State Batteries
Authors: Houache Mohamed , Yan Shuo , MacIver Paul , Karkar Zouina , Yim Chae-Ho , Abu-Lebdeh Yaser
Published: December 2024

The application of Li-ion batteries has been expanding at a rapid rate in recent decades due to the tremendous demands in the market for portable electronics, smart grid, and electric vehicles (EVs). Solid-state lithium metal battery (SS-LMB) is the most promising next-generation energy storage device as they can solve the safety issue resulted from liquid electrolytes.

Among different types of solid-state electrolytes (SSE), garnet-type structure materials have been shown to be very promising for the development of SS-LMBs owing to their wide electrochemical stability window (∼6 V vs Li+/Li), good chemical stability against Li metal, and high Li-ion conductivity (∼10–4 S cm-1 at RT). It is also known that such properties are highly dependent on the doped elements, processing conditions, and microstructures. Therefore, for further applications of Li–garnet in SSBs, it is necessary to optimize such properties through doping engineering. Multi-cationic substitution on (Li7La3Zr2O12) LLZO and how cation entropy affects the structure−property relationships related to charge transport and electrochemical stability have not yet been intensively explored.

In this work, we designed a tri-doping approach with Ga3+ substitution for Li+ and Ti4+ and Ta5+ substitution for Zr4+ to increase Li+ vacancy and enhance ionic conductivity of LLZO by sol-gel method, which can be scaled up for mass production. Dopants (Li7-3xGaxLa3Zr2-yTayTiYO12) were selected based on the literature and modelling. Moreover, the effects of dopants with various stoichiometric ratios on the crystalline phase stability, ionic conductivity, and air stability were investigated.
A Green Synthesis of Battery-Level Carbon Anode from PetCoke Carbon Waste
Authors: Risal Samprash , Milapati Sanam , Robles Hernandez Francisco C , Fan Zheng
Published: December 2024

Petroleum coke (PetCoke) is a byproduct of oil refining that is commonly used as a heating resource and contributing to carbon emissions. Additionally, the presence of heavy metals and sulfur in PetCoke has also raised significant environmental concerns. Moreover, traditional high-temperature PetCoke treatment methods exacerbate greenhouse gas emissions. This study introduces an energy-efficient approach for converting PetCoke into carbon anode materials for solid-state batteries. Utilizing a custom-built laser-based vapor deposition setup, comprising a tube furnace and a nanosecond-pulsed infrared laser (1064 nm), we explored the PetCoke transfer process. Subjecting PetCoke to high power density laser irradiation generates localized high temperatures (~3000°C), initiating sample evaporation. By modulating the local conditions within the tube furnace, e.g., temperature, pressure, and argon flow rate, we can precisely control the kinetic gradient between the PetCoke and the plating substrate. This control is crucial for transforming PetCoke into various carbon forms with tailored microstructure and morphology, while selectively removing sulfur and heavy metals due to their differing nucleation rates on copper foil.

One outcome of this process is the production of high-purity carbon black (C65) with a specific surface area of 400 m2/g, as verified by Brunauer-Emmett-Teller (BET) analysis. The exceptional surface area of C65 facilitates its use in creating a mixed-ionic-electronic conductor (MIEC) layer within all-solid-state batteries, enhancing lithium plating and stripping efficiency during cycling. Our battery design, incorporating C65/Ag/Solid Electrolyte/NMC811 and electrolyte composite, leverages laser-induced evaporation for C65 deposition on copper foil and employs Li6PS5Cl as the solid electrolyte. The resulting solid-state cell exhibits remarkable electrochemical performance, maintaining operation at an impressive current density of 2.4 mA/cm2 and achieving an average coulombic efficiency of 99.5% over 200 cycles.
Development of a Printed Solid-State Battery Cell
Authors: Nikolaev Pasha , Zalar Frank , Hondred John , Lawson Jacob , Feld William , Firsich David , Kichambare Padamkar , Scanlon Larry , Henslee Brian E
Published: December 2024

Solid-state lithium-ion batteries have attracted great attention due to high safety and increased energy density. In this work we report on manufacturing approach and electrochemical performance of solid-state cell utilizing phthalocyanine-based solid state electrolyte (SSE) and lithium metal anode. SSE was aerosol jet-printed onto lithium iron phosphate cathode and tested in coin and pouch cells. Assembly technique development allowed for a stable interface between SSE and anode while preventing soft shorts. Performance at high discharge rates, cycle life and specific capacity improvement will be discussed. Advancements have the potential to improve specific energy and cell safety while maintaining cycle life comparable to that of Li-ion.
Development of High-Areal-Capacity Electrodes for Sulfide-Based All-Solid-State Batteries
Authors: Yamano Akihiro , Takahashi Tsukasa , Inoue Daisuke , Ogata Yoichiro , Morishita Masanori
Published: December 2024

All-solid-state batteries using sulfide-based solid electrolytes with high lithium-ion conductivity equivalent to that of organic electrolyte solution are attracting attention as a next-generation battery with excellent safety. The sulfide-based all-solid-state batteries are especially expected to be used as a power source for electric vehicles, and high-capacity batteries are needed to realize such applications. Increasing in the areal capacity of the electrode by increasing the thickness of the electrode is one of the effective approaches to increasing the capacity of the batteries. Coating metal foils with slurry containing binders used in the fabrication of electrodes for the conventional electrolyte-solution-based lithium-ion batteries is effective for mass production processes, but it causes cracking and delamination in the coating layer when the electrode is made too thick. In addition, the addition of binder to the slurry increases the internal resistance of the battery resulting in lower battery performance. In this study, we developed a fabrication technique for the binder-free and a high areal capacity electrode by vacuum filtration of a slurry containing carbon nanotubes (CNTs) in order to realize high-capacity sulfide-based all-solid-state batteries, and evaluated the charge-discharge performance of the cell. Lithium nickel cobalt manganese oxide (LiNi0.5Co0.2Mn0.3O2, NCM) and artificial graphite (Gr) were used as active materials for the cathode and anode, respectively, and a slurry was prepared by mixing them with an argyrodite-type sulfide solid electrolyte (SE, A-SOLiD®, Mitsui Mining & Smelting Co., Ltd.) and CNTs. The slurry was vacuum filtered and then vacuum dried to obtain cathode and anode. The NCM cathode with a high areal capacity of 4 mAh cm-2 without cracking was obtained by vacuum filtration of the CNT-containing slurry, although it contained no binder. As with the cathode, the Gr anode was also crack-free and had a high areal capacity of 5 mAh cm-2. The NCM cathode and Gr anode thus obtained and the solid electrolyte sheets prepared using the argyrodite-type sulfide solid electrolyte were punched to 13 mm and 14 mm diameters, respectively. A full cell of NCM cathode/SE sheet/Gr anode was fabricated by pressing these staked materials, and the cell performance was evaluated in a coin cell (CR2032 type). The full-cell consisting of NCM cathode and Gr anode prepared by vacuum filtration of CNT-containing slurry showed a stable cycling performance of over 50 cycles.