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Si microparticle (SiMP) anodes feature much lower production cost and higher tap density compared to their nanosized counterparts, which hold great promise for high‐energy‐density lithium‐ion batteries, yet they suffer from unavoidable particle pulverization during repeated cycling, thus making their practical application extremely challenging. Herein, a non‐flammable localized high‐concentration electrolyte (LHCE) is rationally formulated using a fluorinated solvent, 2,2,2‐trifluoroethyl methyl carbonate (FEMC), to induce fluorinated solvent‐coupled anion‐derived interfacial chemistry. Unlike other LHCEs, the FEMC‐based LHCE is demonstrated to build a highly robust and stable F‐rich inorganic–organic bilayer solid–electrolyte interphase on SiMP anode, which endows stable cycling of SiMP anode (≈3.4 mAh cm−2) with an ultrahigh Coulombic efficiency of ≈99.7%. Coupled with its high anodic stability, the FEMC‐based LHCE endows unprecedented cycling stability for high‐energy‐density batteries containing high‐capacity SiMP anodes with Ni‐rich LiNi8Mn1Co1O2 or 5 V‐class LiNi0.5Mn1.5O4 cathodes. Remarkably, a 1.0 Ah‐level SiMP||LiNi8Mn1Co1O2 pouch‐cell stably operates for more than 200 cycles, representing the pioneering report in pouch cells containing SiMP anodes.

As the "holy grail" of lithium battery anode materials, the lithium metal anode suffers from several fatal defects, such as infinite volume expansion and uncontrolled dendrite formation. Herein, a three-dimensional (3D) lithiophilic host that comprises MnO 2 nanoflowers in situ grown on Ni foam (MnO 2 @NF) is developed into a stable lithium metal anode. The 3D porous structure of Ni foam (NF) can greatly reduce the average current density of the electrode and relieve volume changes during the repeated plating/stripping process, in which the MnO 2 nanoflower arrays endow the 3D framework with high lithiophilicity, leading to a reduced lithium nucleation barrier and uniform lithium nucleation. It is found that the MnO 2 nanoarrays could transform into Ni/Li 2 O, which offers abundant lithium deposition sites, homogenizes Li + flux distribution, and ensures fast Li + transfer kinetics. These advantages of MnO 2 @NF enable dendrite-free lithium deposition behavior and excellent electrochemical performance. As a consequence, the asdesigned MnO 2 @NF host delivers a high Coulombic efficiency (CE) of 98.7% for 400 cycles in a half cell under 0.5 mA cm −2 , and an ultralong cycling lifespan of 2000 h with a low-voltage hysteresis of 18 mV is achieved in a symmetrical cell at 1 mA cm −2 . Furthermore, the Li-MnO 2 @NF//LiFePO 4 full cell also exhibits enhanced cyclic stability and rate performance, indicating the application prospects of Li-MnO 2 @NF as a stable lithium metal anode.

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