Li-richening strategy in Li_(2)ZrCl_(6) lattice towards enhanced ionic conductivity

All-solid-state Li batteries(ASSLBs) with solid-state electrolytes(SSEs) are exciting candidates for nextgeneration energy storage and receive considerable attention owing to their reliability. Halide SSEs are promising candidates due to their excellent stability against 4 V-class layered cathodes. Compared with Li3InCl6or Li_(3)ScCl_(6), the low ionic conductivity of Li_(2)ZrCl_(6)(LZC) is a challenge despite its low raw-material cost. Herein, we report a family of Li-Richened chloride, Li_(2+2x)Zr_(1–x)MxCl_(6), which can be used in highperformance ASSLBs owing to its high ionic conductivity(up to 0.62 mS cm^(-1)). The theoretical(ab initio molecular dynamics simulations) and experimental results prove that the strategy of aliovalent substitution with divalent metals to obtain Li-Richened LZC is effective in improving Li^(+)conductivity in SSEs. By combining Li_(2.1)Zr_(0.95)Mg_(0.05)Cl_(6)(Mg5-LZC) with a Li–In anode and a LiCoO_(2)cathode, a room-temperature ASSLBs with excellent long-term cycling stability(88% capacity retention at 0.3C for 100 cycles) and highrate capability(121 m A h g^(-1)at 1C) is reported. This exploratory work sheds light on improving the Li^(+)conductivity of low-cost LZC-family SSEs for constructing high performance ASSLBs.

Halide/sulfide composite solid-state electrolyte for Li-anode based all-solid-state batteries

Li_(2)ZrCl_(6)(LZC) solid-state electrolytes(SSEs) have been recognized as a candidate halide SSEs for allsolid-state Li batteries(ASSLBs) with high energy density and safety due to its great compatibility with4V-class cathodes and low bill-of-material(BOM) cost.However,despite the benefits,the poor chemical/electrochemical stability of LZC against Li metal causes the deterioration of Li/LZC interface,which has a detrimental inhibition on Li^(+) transport in ASSLBs.Herein,we report a composite SSE combining by LZC and argyrodite buffer layer(Li_(6)PS_(5)Cl,LPSC) that prevent the unfavorable interaction between LZC and Li metal.The Li/LPSC-LZC-LPSC/Li symmetric cell stably cycles for over 1000 h at 0.3 mA/cm^(2)(0.15mAh/cm^(2)) and has a high critical current density(CCD) value of 2.1 mA/cm^(2)at 25 ℃,Under high temperature(60℃) which promotes the reaction between Li and LZC,symmetric cell fabricated with composite SSE also display stable cycling performance over 1200h at 0.3 mAh/cm^(2).Especially,the Li/NCM ASSLBs fabricated with composite SSE exhibit a high initial coulombic efficiency,as well as superior cycling and rate performance.This simple and efficient strategy will be instrumental in the development of halidebased high-performance ASSLBs.