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Compared to traditional lithium‐ion batteries with liquid electrolytes, all‐solid‐state lithium batteries have attracted extensive attention due to their heightened safety and energy density. Lithium argyrodite materials are promising solid electrolytes (SE) due to their high ionic conductivity, low grain boundary resistance, and favorable mechanical properties. However, the poor chemical/electrochemical stability of lithium argyrodite electrolytes toward the bare lithium metal anode inhibits their applications in all‐solid‐state lithium metal batteries (ASSLMBs). Here, Li‐SnF2 composite anodeswas used to induce the formation of solid electrolyte interphase (SEI) composed of LiCl, LiF, and Li22Sn5 at the Li/SE interface. The high interface energy barriers for LiF and LiCl induces the uniform deposition of lithium ions, thus hindering the growth of lithium dendrites. Meanwhile, the fast Li‐ion diffusion coefficient of the Li22Sn5 alloy accelerates Li‐ion migration across the interface section. The symmetrical cell exhibits stable cycling performance over long durations over 300 h at 0.5 mA cm−2. Moreover, the LiNbO3@NCM712/Li5.5PS4.5Cl1.5/Li‐10%SnF2 battery delivers a high initial discharge capacity of 170.9 mAh g−1 at 0.1C and retains 72.9% of its original capacity after 500 cycles at 0.5C. The facial approach for Li‐SnF2 composite anode enables the production of ASSLMBs with superior electrochemical performance. [ABSTRACT FROM AUTHOR]

The sufficient and reversible active lithium is the cornerstone for the operation of high‐energy lithium‐ion batteries. However, active lithium is inevitably depleted due to the formation of a solid electrolyte and the presence of irreversible side reactions. The shortage of lithium in optimally designed batteries not only leads to a depreciation of energy density but also deteriorates the electrode structure resulting in degradation of cycle life. Inspiringly, prelithiation technology that additionally compensates for lithium has been proposed and is playing an increasingly significant role in enhancing battery energy density and prolonging cycle life. Herein, guided by the factors that initiate lithium loss, the action mechanism and the effectiveness of prelithiation are scrutinized. Moreover, the emerging advanced prelithiation technologies based on anode/cathode materials, the key barriers, and the applicability at scale are systematically summarized and compared. Integrating the challenges and development trends aspires to provide a comprehensive prelithiated hybrid lithium replenishment and storage technology as a reference in the scale‐up of prelithiation technologies. [ABSTRACT FROM AUTHOR]

Fluorinated solvents emerge as a promising strategy to improve performance of lithium metal batteries (LMBs). However, most of them are prone to produce corrosive HF and deteriorate electrode interface, inducing cathode‐to‐anode detrimental crossover of transition metal‐ions. Here, fluorinated aromatic hydrocarbons in dimethyl carbonate (DMC)‐based diluted highly concentrated electrolyte (DHCE) are employed to juggle formation of HF and LiF, enabling stable cycling of high‐voltage LiNi0.7Co0.1Mn0.2O2 (NCM712) and LiCoO2 (LCO). The nature of aromatics in this carbonate‐based DHCE makes them difficult to undergo β‐hydrogen assisted defluorination, evidencing by the high energy barrier and high bond energy of β‐sites hydrogen. The advanced DHCE restrains HF formation but strengthens LiF formation, which not only suppresses impedance growth, transition‐metal dissolution, and stress crack on the cathode, but achieves highly reversible Li stripping/plating with an outstanding average Coulombic efficiency up to 99.3%. The Li||NCM712 cell and Li||LCO cell both exhibits superior cycling stability at high operation voltage. Even under stringent conditions, the 4.4 V Li||NCM712 full battery retains >95% of the initial capacity over 100 cycles, advancing practical high‐voltage LMBs. This study designs an efficient electrolyte that generates robust electrode/electrolyte interphases and restrains by‐products formation spontaneously, thus shedding new light on electrolyte toward applicable LMBs. [ABSTRACT FROM AUTHOR]

High‐energy density and ultra‐long cycling lifespan are of great significance in pursuit of practical lithium–sulfur (Li‐S) batteries, in which the construction of ultrathick, high‐areal‐capacity, and stable‐cycling sulfur cathodes remains challenging. Here, a unique layered reinforced concrete structure (LRCS) is reported by integrating an ice‐template method with incorporating carbon fibers in the thick electrodes for Li‐S batteries. The LRCS enables aligned through‐channel structure and intertwined conductive network, which lead to both fast kinetics of ions/electrons transport and strengthened electrode integrity to tolerate the volume change during cycling and the dimensional deformation under a high compaction density. Benefiting from the unique structure, the ultra‐thick Se0.05S0.95 @ pPAN cathode (20.2 mg cm−2) delivers a high capacity of 10 mAh cm−2 and excellent capacity retention of 80.8% over 140 cycles at a low electrolyte‐to‐sulfur ratio of 2 and a negative‐to‐positive capacity ratio of 2.7, corresponding to a calculated energy density of 390 Wh kg−1. This investigation not only provides guidance for the design of thick sulfur electrodes but also paves the way for the development of practical Li‐S batteries. [ABSTRACT FROM AUTHOR]

Lithium‐ion batteries (LIBs) suffer from energy loss and safety hazards under high‐rate conditions, because of the sluggish electrochemical kinetics and unstable interfacial passivation. Herein, a PC‐based electrolyte using weakly solvated solvent ethyl trifluoroacetate is developed to improve interfacial kinetics and stability in LIBs. A microsolvating competition is revealed in the bulk electrolyte, forming a loose Li+ coordination configuration with benign Li+ affinity and high ionic conductivity. Furthermore, an inorganic‐rich interphase is constructed on a graphite anode, affording smooth Li+ desolvation and reliable passivation. Consequently, the NCM622/graphite cell in PC‐based electrolyte shows improved cycling stability (82.2% after 200 cycles) and rate capability (83% at 4C compared to 0.1C) at a high‐voltage of 4.5 V, much better than those of EC‐based electrolyte (76.2% after 200 cycles and 74% at 4C). Additionally, the PC‐based electrolyte affords reversible operation at –40 °C while the EC‐based electrolyte fails at –40 °C. This work highlights the potential of solvation structure engineering for low‐energy‐barrier electrolyte. [ABSTRACT FROM AUTHOR]