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Multi‐scale simulation is an important basis for constructing digital batteries to improve battery design and application. LiF‐rich solid electrolyte interphase (SEI) is experimentally proven to be crucial for the electrochemical performance of lithium metal batteries. However, the LiF‐rich SEI is sensitive to various electrolyte formulas and the fundamental mechanism is still unclear. Herein, the structure and formation mechanism of LiF‐rich SEI in different electrolyte formulas have been reviewed. On this basis, it further discussed the possible filming mechanism of LiF‐rich SEI determined by the initial adsorption of the electrolyte‐derived species on the lithium metal anode (LMA). It proposed that individual LiF species follow the Volmer–Weber mode of film growth due to its poor wettability on LMA. Whereas, the synergistic adsorption of additive‐derived species with LiF promotes the Frank‐Vander Merwe mode of film growth, resulting in uniform LiF deposition on the LMA surface. This perspective provides new insight into the correlation between high LiF content, wettability of LiF, and highperformance of uniform LiF‐rich SEI. It disclosed the importance of additive assistant synergistic adsorption on the uniform growth of LiF‐rich SEI, contributing to the reasonable design of electrolyte formulas and high‐performance LMA, and enlightening the way for multi‐scale simulation of SEI. [ABSTRACT FROM AUTHOR]

The lithium metal anode (LMA) is a promising technology to promote the energy density of secondary batteries. However, the coupled growth of surface corrosion and deposited lithium with high reactivity causes capacity fading and safety hazards, especially at high temperatures. Great efforts have been focused on preventing the LMA from direct contact with electrolytes to extend its lifespan, but few pay attention to its stability at high temperatures, which is crucial to battery safety. Herein, a 3D Li22Sn5‐based interpenetrated skeleton is introduced into the bulk of LMA with mechanical kneading, which enables a LMA with fast and stable cycles at high temperatures and improved safety under thermal abuse. The Li22Sn5 skeleton acts as a solid electrolyte inside the bulk, allowing rapid Li+ ion transport and homogenous lithium stripping/plating into the porous bulk through Li/Li22Sn5 interface. The encapsulating framework expands the electrochemically active area and limits its exposure to the electrolyte, enabling a LMA with steady cyclability even at 60 °C. Trapping lithium inside the thermally stable skeleton postpones the catastrophic exothermal reactions between lithium and electrolytes. The strategy for constructing a 3D encapsulating lithiophilic framework is promising for creating safe and stable lithium metal batteries working under harsh circumstances. [ABSTRACT FROM AUTHOR]

Lithium metal batteries (LMBs) have attracted widespread concern as the next‐generation energy storage devices with high energy density. At the surface of lithium metal anodes (LMAs) toward electrolytes, lithium plating always competes with interfacial reactions. This makes interfacial reactions light shadow right behind lithium plating, leading to performance degradation. Herein, lithium plating is spatially decoupled from interfacial reactions by constructing a 3D solid electrolyte interphase framework (3D‐SEIF) inside LMAs. Spontaneous while mild chemical reactions between lithium metal and lithium bisfluorosulfonimide/lithium nitrate form the robust 3D‐SEIF, mainly consisting of LiF, Li3N, and LiNxOy. The built‐in 3D‐SEIF avoids electrolyte contact but enables the diffusion and reduction of Li+ ions in the bulk phase, thus isolating the plating sites and electrolyte contact interface. The 3D‐SEIF facilitates large granular plating and the generation of thin, inorganic‐rich SEI. When assembled with high‐loading LiNi0.6Co0.2Mn0.2O2 cathode (3 mAh cm−2), the cells present capacity retention of 92.0% after 130 cycles with barren electrolyte (≈30 µL) at 0.5 C. The conception of 3D inner interphase allows breaking the coupling of interfacial reactions with electrochemical reactions, which is taken for granted in electrochemical consortium. It also desires to inspire new thoughts to develop scalable solutions for the early industrialization of LMBs. [ABSTRACT FROM AUTHOR]

The conventional knowledge of solid electrolyte interphases (SEIs) is limited to their ionic conductive and electron‐insulating properties. The solvation structure regulation in the new‐concept electrolytes always leads to the regulated SEI, resulting in the improvement of ion desolvation kinetics. However, the linkage between the improved kinetics and the regulated SEl remains unconnected at the atomic level. Herein, this work proposes that the SEI can function more by facilitating ion desolvation. Using quantum chemistry calculations, this work explores the ion desolvation processes with and without SEI. It is found the accelerated ion desolvation in the new‐concept electrolytes is directly attributed to the SEI rather than the regulated solvation structure. Based on the recognition of SEI's role, this work proposes an SEI‐aided ion desolvation model. This study bridges the SEI and battery kinetics at the atomic scale and redefines the functions of SEI, which are expected to steer the electrolyte design in batteries. [ABSTRACT FROM AUTHOR]

Lithium difluorophosphate (LiDFP) is among the most widely applicable additives used to construct a robust solid electrolyte interphase (SEI) on electrode, which can improve the cycling performance and rate performance of high‐voltage cathodes and Li metal anodes at extreme temperatures. Regarding the working mechanism of LiDFP, reasonable but divided understandings have been proposed based on specific battery chemistry. Herein, the broad applications of LiDFP in various electrochemical systems are reviewed and a universal working mechanism based on the state‐of‐the‐art understanding of LiDFP is offered. Then, future directions of the missing part in mechanism comprehension are highlighted. Furthermore, the approaches to effectively apply LiDFP and other similar additives according to their limits are summarized. Finally, questions regarding the missing part of the mechanism are discussed by which LiDFP forms a robust SEI and how these lead to opportunities for future understanding and promotion of interfacial passivation. This study not only provides new knowledge on the mechanism of LiDFP and other existing additives but also helps inspire more effective additive applications. [ABSTRACT FROM AUTHOR]

Highlights: The current issues and recent advances in polymer/inorganic composite electrolytes are reviewed. The molecular interaction between different components in the composite environment is highlighted for designing high-performance polymer/inorganic composite electrolytes. Inorganic filler properties that affect polymer/inorganic composite electrolyte performance are pointed out. Future research directions for polymer/inorganic composite electrolytes compatible with high-voltage lithium metal batteries are outlined. Solid-state electrolytes (SSEs) are widely considered the essential components for upcoming rechargeable lithium-ion batteries owing to the potential for great safety and energy density. Among them, polymer solid-state electrolytes (PSEs) are competitive candidates for replacing commercial liquid electrolytes due to their flexibility, shape versatility and easy machinability. Despite the rapid development of PSEs, their practical application still faces obstacles including poor ionic conductivity, narrow electrochemical stable window and inferior mechanical strength. Polymer/inorganic composite electrolytes (PIEs) formed by adding ceramic fillers in PSEs merge the benefits of PSEs and inorganic solid-state electrolytes (ISEs), exhibiting appreciable comprehensive properties due to the abundant interfaces with unique characteristics. Some PIEs are highly compatible with high-voltage cathode and lithium metal anode, which offer desirable access to obtaining lithium metal batteries with high energy density. This review elucidates the current issues and recent advances in PIEs. The performance of PIEs was remarkably influenced by the characteristics of the fillers including type, content, morphology, arrangement and surface groups. We focus on the molecular interaction between different components in the composite environment for designing high-performance PIEs. Finally, the obstacles and opportunities for creating high-performance PIEs are outlined. This review aims to provide some theoretical guidance and direction for the development of PIEs. [ABSTRACT FROM AUTHOR]

Monoclinic natrium superionic conductors (NASICON; Na3Zr2Si2PO12) are well‐known Na‐ion solid electrolytes which have been studied for 40 years. However, due to the low symmetry of the crystal structure, identifying the migration channels of monoclinic NASICON accurately still remains unsolved. Here, a cross‐verified study of Na+ diffusion pathways in monoclinic NASICON by integrating geometric analysis of channels and bottlenecks, bond‐valence energy landscapes analysis, and ab initio molecular dynamics simulations is presented. The diffusion limiting bottlenecks, the anisotropy of conductivity, and the time and temperature dependence of Na+ distribution over the channels are characterized and strategies for improving both bulk and total conductivity of monoclinic NASICON‐type solid electrolytes are proposed. This set of hierarchical ion‐transport algorithms not only shows the efficiency and practicality in revealing the ion transport behavior in monoclinic NASICON‐type materials but also provides guidelines for optimizing their conductive properties that can be readily extended to other solid electrolytes. [ABSTRACT FROM AUTHOR]

Multifunctional 3D Hollow Spherical Porous Organic Polymer (HS-POP) has been introduced to construct a rubust artificial SEI for Li metal anode. The effective coordination of energetic lithiophilic groups and hollow spherical POP buffering effect favors to promote the uniform Li+ distribution and relieve the volumic stress caused by Li depostion swelling. The enhanced electrochemical performances have been corroborated via extensively experimental data and theoretical calculations. [Display omitted] • The 3D HS-POP provides an excellent buffering effect against to bulk Li expansion. • The affinity groups of HS-POP expedite Li+ transfer with decreased energy barrier. • HS-POP layer can intercept TFSI– shuttling and inhibit the anions decomposition. Li metal is regarded as one of the most promising anodes in rechargeable battery systems for its high theoretical specific capacity, low redox potential and light weight. However, Li dendritic formation and low Coulombic efficiency (CE) triggered by the nonuniform Li+ deposition restrict the further step to the commercialization of lithium metal batteries. Herein, a fantastic hollow spherical porous organic polymer (HS-POP) with concentrated lithiophilic functional groups of –C=N, –OH has been synthesized and utilized as an artificial solid electrolyte interphase (SEI) to regulate the interfacial stability of Li metal anode. The compelling evidences of density functional theory (DFT) calculations and Fourier-transform infrared spectra verified the energetical lithiophilic property, which facilitates Li+ uniform transfer and nucleation with decreased energy barriers. The large cavities and well-flexible shell structure not only provide enlarged lithium storage capacity, but also act as a buffer layer during repeated Li deposition and dissolution protocols. The HS-POP modified Li anode delivered a higher CE at high current density of 2 mA cm−2, and the HS-POS@Li|S full cell demonstrates excellent performance with high reversible capacity for 400 cycles at 0.5 C. [ABSTRACT FROM AUTHOR]