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Lithium‐metal anodes (LMAs) are the ultimate choice for realizing high‐energy‐density batteries; however, its use is hindered by problematic Li growth in the form of dendrites. To alleviate dendritic Li growth, the preparation of LMAs with a lithiophilic current collector (CC) is effective; however, applying a lithiophilic CC to LMAs is still challenging due to the manufacturing complexity involved in the separate lithiophilic treatment and lithiation processes. Herein, a facile one‐pot LMA fabrication method by utilizing thiourea (TU) as a precursor is proposed. A lithiophilic Cu2S layer is formed on Cu foam (CF) by the in situ electrochemical oxidation of TU (CuxSCF), and the lithiation of CC is performed via subsequent Li electrodeposition (Li@CuxSCF). The Cu2S on CuxSCF can lead to uniform Li deposition by providing lithiophilic sites, and it is converted to form ionic‐conductive Li2S‐rich solid electrolyte interphase layer. Resultantly, CuxSCF significantly enhances the cycling performance of LMAs compared to CF. Specifically, a LiFePO4/Li@CuxSCF full‐cell lithium‐metal battery (LMB) with a low n/p ratio (1.6) exhibits capacity retention of 95.6% at 0.5 C (220 cycles) and can maintain 85.0% of initial capacity (425 cycles, n/p = 4) at 2.0 C. LMBs with LiNi0.6Co0.2Mn0.2 and LiNi0.8Co0.1Mn0.1 also exhibit improved electrochemical performance. [ABSTRACT FROM AUTHOR]

All‐solid‐state Li‐metal battery (ASSLB) represents advantageous energy storage system for automotive applications. For ASSLB, inorganic solid electrolyte is essential in determining safety and cycling performance. However, significant challenges persist in practical construction of ASSLB with optimized electrolyte. Specifically, electrolyte's structural instability influencing its electrochemical performance remains critical issue within typical operating temperatures for ASSLB in electric vehicles. Herein, this challenge is fundamentally addressed by substituting trace amount of lithium with cadmium, which lacks crystal field stabilization energy. This strategy of atomic interaction modification has induced electrolyte's structural distortion and electronic alteration by deliberately introducing disorder at local lithium sites. Li symmetric cell with cadmium‐substituted antiperovskite solid electrolyte exhibits outstanding critical current density of 11.5 mA cm−2 (5.75 mAh cm−2) and excellent stability for 3000 h at 10.0 mA cm−2 (5.0 mAh cm−2). This study highlights explicit research direction for breakthrough of ASSLB, focusing on understanding how local distortion affects complex inorganic materials. [ABSTRACT FROM AUTHOR]

Anode‐free manufacturing holds promise to enable high energy densities and lower Lithium (Li)‐metal solid‐state batteries (LMSSBs). Nevertheless, in contrast to thick Li foil (>50 µm), the stripping capacity of in situ‐formed Li (10–30 µm) is limited due to diminished creep flow, resulting in reduced accessible capacity. This study explores the correlation between stripping capacity and surface roughness of garnet Li7La3Zr2O12 (LLZO) solid electrolyte. The results reveal that stripping capacity can be enhanced through the surface modification of solid electrolytes. Additionally, this study scrutinizes the stripping behavior of in situ Li under intermittent‐current discharge conditions, which are more relevant to the operational conditions of electric vehicles (EVs). It is demonstrated that, when compared to constant‐current stripping, intermittent‐current stripping effectively suppresses void formation and enhances the stripping capacity of in situ Li by 40%. It is considered that the intermittent current inhibits the accumulation of Li vacancies, thereby delaying the void formation. These findings provide valuable insights into the development of high‐performance anode‐free LMSSBs for EVs. [ABSTRACT FROM AUTHOR]

Despite the relatively low stiffness of sulfide solid‐state electrolytes (SSEs), which makes them capable of better formability and accommodation for volume changes of active materials, the low fracture toughness (KIC) indicates a high susceptibility to fracture caused by electrochemo‐mechanical stresses. This susceptibility to mechanical damages and the subsequent lithium filament penetration, manifesting as micro‐short circuit events, seriously hinders the practical application of lithium metal in high‐energy‐density sulfide‐based all‐solid‐state lithium metal batteries (ASSLMBs). A full understanding of the stress evolution of Li metal anodes during cycling is key to decoding the mechanical damage‐induced micro‐short circuit behavior. Here, an operando and quantitative measurement of the stress evolution of an LTO/SSE/Li configuration all‐solid‐state battery (ASSB) operating with various parameters, including cell capacity and current density, is shown. Two micro‐short circuit modes and their corresponding mechanisms are revealed based on the electrochemo‐mechanical response of the Li metal anode. Furthermore, a finite element model (FEM) is used to explain this mechanical failure and a ′safety zone″ for the Li metal anode related to the ′internal stress″ is given. These findings provide new insight into the micro‐short circuit events induced by electrochemo‐mechanical damage in sulfide‐based ASSLMBs. [ABSTRACT FROM AUTHOR]

As a potential candidate for next‐generation energy storage systems, Li–O2 batteries (LOBs) with their attractive theoretical energy density have triggered great interest. However, tough issues of sluggish oxygen reduction reaction/oxygen evolution reaction (ORR/OER) kinetics, poor rechargeability, superoxide‐derived side reactions, and Li‐metal corrosion in LOBs limit their practical applications. Herein, a poly(2,2,2‐trifluoroethyl methacrylate) (PTFEMA) additive is introduced into the typical electrolyte, giving superior cycling performance to LOBs. Enabling strong solvation of Li+, PTFEMA regulates a uniform Li+ flow at the cathode and anode sides of LOBs. Induced by homogeneous Li+ flux and favorable adsorption with superoxide species, PTFEMA promotes superoxide transformation in the ORR and inhibits superoxide‐induced parasitic reactions. Uniform Li+ flux gives evenly‐distributed Li2O2 that can be completely decomposed during OER. In addition, PTFEMA protects Li‐metal against corrosion from O2, superoxide, and byproducts shuttle. Hence, accelerated ORR/OER kinetics, facilitated rechargeability, suppressed superoxide‐derived side reactions, and well‐protected Li‐metal can be simultaneously realized with PTFEMA, resulting in significantly enhanced electrochemical performance of LOBs. This electrolyte engineering involving facile multifunctional polymer additives provides a practical alternative to complex componential optimization toward commercial LOBs and gives insight to the understanding of uniform Li+ flux on reaction kinetics and reversibility. [ABSTRACT FROM AUTHOR]

Interfacial instability between Li‐metal anode (LMA) and inorganic solid‐state electrolyte (SSE) is a critical issue in all‐solid‐state Li‐metal batteries (ASSLBs). Previous studies have focused on interface modification methodology to achieve long‐term cycling stability in ASSLBs. However, strategy establishment without an in‐depth understanding of the LMA–SSE interface is limited to a phenomenological solution. Also, the fact that rechargeable batteries are operated by behavior of charges inside electric field is frequently overlooked. Here, it is demonstrated for the first time that interface modeling based on energy band theory does effectively overcome the intrinsic vulnerability of SSE to LMA. The interfacial deterioration, due to undesirable electron transport from LMA to the SSE surface, is precluded by a titanium compound self‐induced interlayer (TSI), which forms an interfacial energy barrier. The Li symmetric cell with a TSI successfully maintains its constant overpotential over 1000 cycles and the significantly reduced impedance, whereas the cell having no interface modification exhibits erratic voltage profiles and is easily failed by repetitive charge–discharge process. This newly introduced approach is an informative tool to substantially reinforce the fundamental understanding of interfacial phenomena in all‐solid‐state batteries. Furthermore, rigorous stability requirements of automotive applications are expected to be fulfilled by the innovative interface modification. [ABSTRACT FROM AUTHOR]

Lithium (Li) metal is one of the most promising anode candidates for next‐generation rechargeable batteries with a high energy density because of its high theoretical specific capacity and low reduction potential. However, the growth of lithium dendrites causes intolerable safety risks and poor electrochemical performances. Limiting the migration of anions near the Li‐metal anode is regarded as an effective strategy to achieve uniform Li deposition and thus suppress the dendritic growth. Here, a metal‐organic frameworks based polyvinylidene fluoride‐hexafluoropropylene copolymer composite interlayer is designed and prepared through an in situ heat‐assisted method. Being guided and assisted by the anion‐shielded composite interlayer, a homogenous Li‐ion flux as well as a high Li‐ion transference number are achieved, which promotes the uniform and stable lithium deposition. At the same time, the robust composite interlayer is expected to suppress the growth of Li dendrites by its intrinsically high modulus (≈2.49 GPa). As a result, symmetrical batteries exhibit excellent cyclic stability for over 1600 h with functional composite interlayer. Furthermore, full cells with a commercial lithium iron phosphate cathode demonstrate remarkably enhanced cycling performance with a satisfying capacity retention of 96 % after 500 cycles. This work provides an effective strategy for the design and fabrication of functional composite interlayers to realize stable lithium metal anodes. [ABSTRACT FROM AUTHOR]

The growing demand for sustainable energy storage devices requires rechargeable lithium‐ion batteries (LIBs) with higher specific capacity and stricter safety standards. Ni‐rich layered transition metal oxides outperform other cathode materials and have attracted much attention in both academia and industry. Lithium‐ion batteries composed of Ni‐rich layered cathodes and graphite anodes (or Li‐metal anodes) are suitable to meet the energy requirements of the next generation of rechargeable batteries. However, the instability of Ni‐rich cathodes poses serious challenges to large‐scale commercialization. This paper reviews various degradation processes occurring at the cathode, anode, and electrolyte in Ni‐rich cathode‐based LIBs. It highlights the recent achievements in developing new stabilization strategies for the various battery components in future Ni‐rich cathode‐based LIBs. [ABSTRACT FROM AUTHOR]

With its high theoretical capacity, lithium (Li) metal is recognized as the most potential anode for realizing a high‐performance energy storage system. A series of questions (severe safety hazard, low Coulombic efficiency, short lifetime, etc.) induced by uncontrollable dendrites growth, unstable solid electrolyte interface layer, and large volume change, make practical application of Li‐metal anodes still a threshold. Due to their highly appealing properties, carbon‐based materials as hosts to composite with Li metal have been passionately investigated for improving the performance of Li‐metal batteries. This review displays an overview of the critical role of carbon‐based hosts for improving the comprehensive performance of Li‐metal anodes. Based on correlated mainstream models, the main failure mechanism of Li‐metal anodes is introduced. The advantages and strategies of carbon‐based hosts to address the corresponding challenges are generalized. The unique function, existing limitation, and recent research progress of key carbon‐based host materials for Li‐metal anodes are reviewed. Finally, a conclusion and an outlook for future research of carbon‐based hosts are presented. This review is dedicated to summarizing the advances of carbon‐based materials hosts in recent years and providing a reference for the further development of carbon‐based hosts for advanced Li‐metal anodes. [ABSTRACT FROM AUTHOR]

Lithium metal is regarded as the "Holy Grail" of anode materials due to its low electrochemical potential and high theoretical capacity. Unfortunately, its unstable solid electrolyte interphase (SEI) leads to low Coulombic efficiency (CE) and serious safety issues. Herein, a hybrid nanoscale polymeric protective film with tunable composition and improved stiffness is developed by incorporating aluminum crosslinkers into the polymer chains. The Li plating/stripping process is regulated through the protective coating and the dendrite growth is effectively suppressed. Promisingly, the protected Li can deliver stable performance for more than 350 h with a cycling capacity of 2 mAh cm−2 without a notable increase in overpotential. Moreover, a stable charge/discharge cycling in Li–O2 batteries with the protected Li can be maintained for more than 600 h. This work provides guidance on the rational design of electrode interfaces and opens up new opportunities for the fabrication of next‐generation energy storage systems. [ABSTRACT FROM AUTHOR]

Chemical and electrochemical instability of the Li metal interface with organic solvent has been a major impediment to use of Li-metal anodes for next-generation batteries. Here the character of Li surface degradation and the application of atomic layer deposition (ALD) as a protection layer to suppress the degradation are addressed. Using standard Li foil samples in organic solvent with and without in situ deposited ALD Al2O3 protective layers, results from in situ atomic force microscopy, mass spectrometry (including differential electrochemical mass spectrometry), X-ray Photoelectron Spectroscopy (XPS), and ex situ scanning electron microscopy/energy dispersive X-ray spectroscopy are reported. Despite the presence of a thin oxide/hydroxide/carbonate layer on the Li foil surface, degradation readily occurs in organic solvent, particularly at surface features such as ridges. Introduction of the ALD protective layer - deposited directly on this Li foil surface - dramatically suppresses the degradation. [ABSTRACT FROM AUTHOR]