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Abstract Lithium metal, with ultrahigh theoretical specific capacity, is considered as an ideal anode material for the lithium‐ion batteries. However, its practical application is severely plagued by the uncontrolled formation of dendritic Li. Here, a cation‐loaded porous Mg2+‐Zeolite layer is proposed to enable the dendrite‐free deposition on the surface of Li metal anode. The skeleton channels of zeolite provide the low coordinated Li+‐solvation groups, leading to the faster desolvation process at the interface. Meanwhile, anions‐involved solvation sheath induces a stable, inorganic‐rich SEI, contributing to the uniform Li+ flux through the interface. Furthermore, the co‐deposition of sustained release Mg2+ realizes a new faster migration pathway, which proactively facilitates the uniform diffusion of Li on the lithium substrate. The synergistic modulation of these kinetic processes facilitates the homogeneous Li plating/stripping behavior. Based on this synergistic mechanism, the high‐efficiency deposition with cyclic longevity exceeding 2100 h is observed in the symmetric Li/Li cell with Mg2+‐Zeolite modified anode at 1 mA cm−2. The pouch cell matched with LiFePO4 cathode fulfills a capacity retention of 88.4% after 100 cycles at a severe current density of 1 C charge/discharge. This synergistic protective mechanism can give new guidance for realizing the safe and high‐performance Li metal batteries.

Abstract With the rapid development of energy storage technology, solid‐state lithium batteries with high energy density, power density, and safety are considered as the ideal choice for the next generation of energy storage devices. Solid electrolytes have attracted considerable attention as key components of solid‐state batteries. Compared with inorganic solid electrolytes, solid polymer electrolytes have better flexibility, machinability, and more importantly, better contact with the electrode, and low interfacial impedance. However, its low ionic conductivity, narrow electrochemical stability window (ESW), and poor mechanical properties at room temperature limit its development and practical applications. In recent years, many studies have focused on improving the ionic conductivity of polymer electrolytes; however, few systematic studies and reviews have been conducted on their ESWs. A polymer electrolyte with wide electrochemical window will aid battery operation at a high voltage, which can effectively improve their energy density. Moreover, their stability toward lithium metal anode is also important. Therefore, this review summarizes the recent progress of solid polymer electrolytes on the ESW, discusses the factors affecting ESW of polymer electrolytes, and analyzes a strategy to broaden the window from the perspective of molecular interaction, polymer structural design, and interfacial tuning. The development trends of polymer electrolytes with wide electrochemical windows are also presented.

Argyrodite-type solid electrolyte have attracted great attention due to its high ionic conductivity and stability to lithium anode. In this experiment, argyrodite-type Li6PS5Cl was prepared by the solid-state method. The Li6PS5Cl solid electrolyte prepared by the solid-state sintering process has more pore and defects, resulting in lower ion conductivity of the electrolyte. The highest ionic conductivity was only 9.58 × 10−4 S cm−1. In order to decrease the defects in the Li6PS5Cl, a new type of second sintering process is used. The highest ionic conductivity obtained by this new process was up to 3.19 × 10−3 S cm−1, which was a relatively high value in currently reported. Industrial Computed Tomography (CT) technology was an advanced characterization method to observe the quantity, size, and distribution of defects inside the sample without any damage. In this experiment, industrial CT was used to detect the pores in Li6PS5Cl., finding that the second sintering process successfully reduces the quantity and size of pores in Li6PS5Cl solid electrolyte, uniforming the distribution of pores thus improving the ion conductivity of the Li6PS5Cl solid electrolyte. This new preparation and characterization method might provide a new idea for the further research of Li6PS5Cl.