Fig.1

ccp structure of Li x ScCl3+x （a）［28］，hcp structure of Li3YCl6（b）［26］，spinel structure of α-Li2ZrCl6，spinel structure of β-Li2ZrCl6（c）［47］，WT spectra of 1.6Li2O-TaCl5，1.8Li2O-TaCl5 at Ta L3-edge with a k2 weighting（d）［18］，local structures of xLi2O-TaCl5 amorphous solid electrolytes（e）［18］，schematic diagram of surface-bulk heterogeneity in BM-SmCl3·0.5LiCl（f）［19］， and schematic diagram of heterogeneous halide composites（g）［48］"

Fig.2

Schematic diagram of Li3InCl6 reaction mechanism in air environment（a）［61］，photos of macroscopic morphology changes of Li3InCl6 powder and Li3InCl6 pellets over time（b）［61］，mechanism schematic diagram of air-stability properties and structural reversibility for Li2ZrCl6 and Li2.8Zr0.2In0.8Cl6 electrolytes（c）［62］，schematic diagram of humidity tolerance of hc-Li2+x Zr1-x In x Cl6 （0≤x≤1）（d）［64］"

Fig.3

Schematic band diagrams of HOMO and LUMO of different classes of electrolytes（a）［65］，calculated thermodynamic equilibrium voltage profile and phase equilibria of LYC and LYB（b）［66］，calculated thermodynamics intrinsic electrochemical windows of Li-M-X ternary fluorides，chlorides，bromides，iodides，oxides，and sulfides，M is a metal cation at its highest common valence state（c）［66］，calculated electrochemical windows of Li3MF6（M=Al，Ti，Cr，Sc，Ga，In）（d）［30］，non-reactive and thermodynamically stable interface（e），reactive and mixed conducting interphase （MCI）（f），and reactive and metastable solid-electrolyte interphase （SEI）（g）［69］"

Fig.4

Schematic illustration of lithium metal deposition on SE with an argon sputter gun and subsequent X-ray photoelectron spectroscopy，X-ray photoelectron（a）［72］，In 3d（b），auger In MNN（c）［72］ and Li 1s spectra during/after lithium deposition on Li3InCl6（d），schematic of digital of LYC-C-coated NCA electrodes for which carbon additives and LYC are added to facilitate electronic conduction pathways（e）［76］，rate capabilities at 30 ℃ for LYC-C （or LYC） coated electrodes（f）［76］，and calculated thermodynamic equilibrium voltage profiles and phase equilibria for Li2ZrCl5.6F0.4（g）［80］"

Fig.5

Impedance evolution of LiCoO2-Li3InCl6|Li3InCl6|In cells during cycling［14］（a），XPS spectra of pristine annealed-Li3InCl6，LiCoO2--Li3InCl6 cathode composites，LiCoO2-Li3InCl6 cathode after first charge，and LiCoO2-LIC cathode after 10 cycles，In L-edge and Cl K-edge XANES spectra of pristine annealed-LIC，LiCoO2-Li3InCl6 cathode composite，and LiCoO2-Li3InCl6 cathode composites collected after first charge and after first discharge（b）［14］，illustration of in-situ synthesis of Li3InCl6 on LiCoO2（LIC@LCO）（c）［82］，calculated electrochemical stability windows of Li3N，Li2O，LiF，LiAlO2，Li3PO4 and LiAlF4，illustration of ALD synthesis of LiAlF4 on NMC-811（d）［16］，calculated mutual reaction enthalpy between SSE and LiCoO2 as a function of mixing ratio and the corresponding phase equilibria at lowest point along the energy convex hull（e）［28］，proposed mechanism of interfacial degradation during aging（f）［83］，and Nyquist plots of composite cathodes aged at 70 ℃ for prolonged period（g）［83］"