Search

Although all‐solid‐state batteries are suggested as a means to tackle the safety concerns associated with current Li‐ion batteries, there is presently a lack of comprehensive understanding regarding their thermal safety. In this context, critical factors contributing to the thermal runaway of thiophosphate solid electrolytes with charged Li1‐xNi0.8Co0.1Mn0.1O2 (NCM) under thermal and mechanical abuse conditions are demonstrated, considering parameters such as heating rate under thermal abuse conditions and the hybridization of S atom in structure. In particular, the thermal behavior of various solid electrolytes, including thiophosphates, thioantimonates, and halides, is investigated to clarify critical elements in Li6PS5Cl (LPSCl) contributing to its thermal instability when combined with charged NCM. Various ex situ analyses, along with density functional theory calculations, reveal a correlation between the hybridization of S atoms and the thermal instability of solid electrolytes, suggesting that sulfur acts as a key element triggering the thermal runaway of sulfide‐based solid electrolytes. [ABSTRACT FROM AUTHOR]

Lithium (Li) metal, with its unparalleled theoretical capacity and lowest electrochemical potential, is a promising anode material for rechargeable batteries. Yet, challenges such as dendrite formation, severe electrode volume change, and ongoing Li consumption impede its practical adoption. To address these challenges, a novel approach is introduced, harnessing the switchable electrical conductivity of a nanoporous current collector for Li metal anode. A vertically aligned Nickel‐catecholate (VANC) is directly grown on the copper foil as the nanoporous current collector, and the Li intercalation and de‐intercalation of VANC reversibly decrease and increase the electrical conductivity in the direction perpendicular to the electrode, respectively. The switchable conductivity induces uniform deposition and stripping of Li metal without forming dendrite and dead Li during the Li plating/stripping process and thus enables high coulombic efficiency of over 98% even after 200 cycles. This nanoporous structure with switchable conductivity will open up a new path for reliable lithium metal anode for rechargeable battery applications. [ABSTRACT FROM AUTHOR]

Lithium–sulfur batteries (LSBs) have drawn significant attention owing to their high theoretical discharge capacity and energy density. However, the dissolution of long‐chain polysulfides into the electrolyte during the charge and discharge process ("shuttle effect") results in fast capacity fading and inferior electrochemical performance. In this study, Mn2O3 with an ordered mesoporous structure (OM‐Mn2O3) was designed as a cathode host for LSBs via KIT‐6 hard templating, to effectively inhibit the polysulfide shuttle effect. OM‐Mn2O3 offers numerous pores to confine sulfur and tightly anchor the dissolved polysulfides through the combined effects of strong polar–polar interactions, polysulfides, and sulfur chain catenation. The OM‐Mn2O3/S composite electrode delivered a discharge capacity of 561 mA h g−1 after 250 cycles at 0.5 C owing to the excellent performance of OM‐Mn2O3. Furthermore, it retained a discharge capacity of 628 mA h g−1 even at a rate of 2 C, which was significantly higher than that of a pristine sulfur electrode (206 mA h g−1). These findings provide a prospective strategy for designing cathode materials for high‐performance LSBs. [ABSTRACT FROM AUTHOR]

With the growing popularity of Li‐ion batteries in large‐scale applications, building a safer battery has become a common goal of the battery community. Although the small errors inside the cells trigger catastrophic failures, tracing them and distinguishing cell failure modes without knowledge of cell anatomy can be challenging using conventional methods. In this study, a real‐time, non‐invasive magnetic field imaging (MFI) analysis that can signal the battery current‐induced magnetic field and visualize the current flow within Li‐ion cells is developed. A high‐speed, spatially resolved MFI scan is used to derive the current distribution pattern from cells with different tab positions at a current load. Current maps are collected to determine possible cell failures using fault‐simulated batteries that intentionally possess manufacturing faults such as lead‐tab connection failures, electrode misalignment, and stacking faults (electrode folding). A modified MFI analysis exploiting the magnetic field interference with the countercurrent‐carrying plate enables the direct identification of defect spots where abnormal current flow occurs within the pouch cells. [ABSTRACT FROM AUTHOR]

Lithium metal batteries (LMBs) are in the spotlight as a next‐generation battery due to their high theoretical capacity. However, LMBs still suffer from inferior cycle stability owing to dendritic lithium (Li) growth during Li plating and stripping, leading to battery explosion. To solve this problem, solid electrolytes have emerged as a promising candidate by suppressing the dendritic Li growth. Despite numerous efforts, however, many challenges, such as low ionic conductivity, air stability, space charge layer, and contact loss issues, have been encountered. This review aims to provide the current challenges and new insights of solid electrolytes and then explore optimal solutions for next‐generation solid electrolytes. [ABSTRACT FROM AUTHOR]

Introducing dielectric materials is a promising approach to mitigate space‐charge‐layer (SCL) formation, which negatively affects the electrochemical performance of sulfide‐based all‐solid‐state batteries (ASSBs). Most previous studies have focused on mitigating SCL formation by introducing dielectric materials, overlooking the fact that significant dielectric properties such as the dipole moment direction and the magnitude of the dielectric constant can influence SCL formation. To clarify the unclear mechanism of dielectric materials mitigating SCL formation, paraelectricity, ferroelectricity, and the magnitude of the dielectric constant are investigated to determine their effect on SCL formation. Paraelectric materials possessing no permanent dipole moment can effectively mitigate the SCL formation better than ferroelectric material with strong permanent dipole moment because of the intrinsic characteristics of the paraelectric material, in which the dipole moment can be aligned along the direction of the electric field applied inside of ASSB. Furthermore, paraelectric materials with a larger dielectric constant have a greater effect in mitigating SCL effect than paraelectric materials with a smaller dielectric constant. Thus, these properties should be considered in cathode‐solid‐electrolyte interface design. This study considers relevant dielectric material characteristics that had not been considered previously, suggesting a new paradigm for optimizing the interfacial resistance of sulfide‐based ASSBs originating from SCL formation. [ABSTRACT FROM AUTHOR]

Utilization of lithium (Li) metal anode is highly desirable for achieving high energy density batteries. Even so, the unavoidable features of Li dendritic growth and inactive Li are still the main factors that hinder its practical application. During plating and stripping, the solid electrolyte interphase (SEI) layer can provide passivation, playing an important role in preventing direct contact between the electrolyte and the electrode in Li metal batteries. Because of complexities of the electrolyte chemical and electrochemical reactions, the various formation mechanisms for the SEI are still not well understood. What we do know is that a strategic artificial SEI achieved through additives electrolyte can suppress the Li dendrites. Otherwise, the dendrites keep generating an abundance of irreversible Li, resulting in severe capacity loss, internal short‐circuiting, and cell failure. In this minireview, we focus on the phenomenon of dendritic Li‐growth and provide a brief overview of SEI formation. We finally provide some clear insights and perspectives toward practical application of Li metal batteries. [ABSTRACT FROM AUTHOR]

Summary: Understanding the role of the oxygen content in silicon suboxides (SiOx) is important for the improvement of their performance as promising negative electrode materials for Li‐ion batteries. Furthermore, sufficient research has not been conducted on tailoring the oxidation of silicon suboxides to employ them as anodes. To address these limitations, we demonstrated the lithiation of SiO2 and amorphous SiOx up to four Li atoms per SiOx and performed density functional theory calculations to examine the energetics, structural evolution, charge effects, mechanical properties, and volume energy density of lithiated a‐SiOx. Our calculations show that two Li defects effectively break a Si‐O bond in SiO2 and a single Li defect is easily stabilized by oxygen in a‐SiOx. With lithiation, oxygen‐tailored SiOx exhibits a difference in volume change and in voltage profiles. The tradeoff between the decreasing volume change ratio and increasing potential as the O content increases results in varied volume energy densities. The detailed reduction mechanism of Li in the a‐SiOx system was analyzed by calculating the Bader charge. Our results emphasize the importance of tailoring the O content to obtain desired lithiation properties and give the physical insight of the development and rational design strategy of high‐performance SiOx anodes dependent on the oxidation conditions. [ABSTRACT FROM AUTHOR]

Lithium (Li) metal is regarded as the most attractive anode material for high‐energy Li batteries, but it faces unavoidable challenges—uncontrollable dendritic growth of Li and severe volume changes during Li plating and stripping. Herein, a porous carbon framework (PCF) derived from a metal–organic framework (MOF) is proposed as a dual‐phase Li storage material that enables efficient and reversible Li storage via lithiation and metallization processes. Li is electrochemically stored in the PCF upon charging to 0 V versus Li/Li+ (lithiation), making the PCF surface more lithiophilic, and then the formation of metallic Li phase can be induced spontaneously in the internal nanopores during further charging below 0 V versus Li/Li+ (metallization). Based on thermodynamic calculations and experimental studies, it is shown that atomically dispersed zinc plays an important role in facilitating Li plating and that the reversibility of Li storage is significantly improved by controlled nanostructural engineering of 3D porous nanoarchitectures to promote the uniform formation of Li. Moreover, the MOF‐derived PCF does not suffer from macroscopic volume changes during cycling. This work demonstrates that the nanostructural engineering of porous carbon structures combined with lithiophilic element coordination would be an effective approach for realizing high‐capacity, reversible Li‐metal anodes. [ABSTRACT FROM AUTHOR]

This study presents a simple and effective method of reducing amorphous silica (a-SiO2) with Ti metal through high-energy mechanical milling for improving its reactivity when used as an anode material in lithium-ion batteries. Through thermodynamic calculations, it is determined that Ti metal can easily take oxygen atoms from a-SiO2 by forming a thermodynamically stable SiO2− x/TiO x composite, meaning that electrochemically inactive a-SiO2 is partially reduced by the addition of Ti metal powder during milling. This mechanically reduced SiO2− x/TiO x composite anode exhibits a greatly improved electrochemical reactivity, with a reversible capacity of more than 700 mAh g−1 and excellent cycle performance over 100 cycles. Furthermore, an enhancement in the mechanical and thermal stability of the composite during cycling can be mainly attributed to the in situ formation of the SiO2− x/TiO x phase. These findings provide new insight into the rational design of robust, high-capacity, Si-based anode materials, as well as their reaction mechanism. [ABSTRACT FROM AUTHOR]

Keywords: Lithium metal anode; Lithium dendrite growth; Solid-electrolyte interphase (SEI); Electrolyte additives; Anode-free EN Lithium metal anode Lithium dendrite growth Solid-electrolyte interphase (SEI) Electrolyte additives Anode-free 4008 4008 1 12/15/21 20211213 NES 211213 B Lithium metal anode b is highly desirable for high-energy density batteries. Cover Feature: Strategic Approaches to the Dendritic Growth and Interfacial Reaction of Lithium Metal Anode (Chem. Lithium metal anode, Lithium dendrite growth, Solid-electrolyte interphase (SEI), Electrolyte additives, Anode-free. [Extracted from the article]