Solid polymer electrolytes(SPEs)are urgently required to achieve practical solid-state lithium metal bat-teries(LMBs)and lithium-ion batteries(LIBs).Herein,we proposed a mechanism for modulating interfa-cial conduction and anode interfaces in high-concentration SPEs by LiDFBOP.Optimized electrolyte exhibits superior ionic conductivity and remarkable interface compatibility with salt-rich clusters:(1)polymer-plastic crystal electrolyte(P-PCE,TPU-SN matrix)dissociates ion pairs to facilitate Li+transport in the electrolyte and regulates Li+diffusion in the SEI.The crosslinking structure of the matrix compen-sates for the loss of mechanical strength at high-salt concentrations;(2)dual-anion TFSI-n-DFBOP-m in the Li+solvation sheath facilitates facile Li+desolvation and formation of salt-rich clusters and is con-ducive to the formation of Li conductive segments of TPU-SN matrix;(3)theoretical calculations indicate that the decomposition products of LiDFBOP form SEI with lower binding energy with LiF in the SN sys-tem,thereby enhancing the interfacial electrochemical redox kinetics of SPE and creating a solid interface SEI layer rich in LiF.As a result,the optimized electrolyte exhibits an excellent ionic conductivity of 9.31 × 10-4 S cm-1 at 30 ℃ and a broadened electrochemical stability up to 4.73 V.The designed elec-trolyte effectively prevents the formation of Li dendrites in Li symmetric cells for over 6500 h at 0.1 mA cm-2.The specific Li-Si alloy-solid state half-cell capacity shows 711.6 mAh g-1 after 60 cycles at 0.3 A g-1.Excellent rate performance and cycling stability are achieved for these solid-state batteries with Li-Si alloy anodes and NCM 811 cathodes.NCM 811||Prelithiated silicon-based anode solid-state cell delivers a discharge capacity of 195.55 mAh g-1 and a capacity retention of 97.8％after 120 cycles.NCM 811||Li solid-state cell also delivers capacity retention of 84.2％after 450 cycles.
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