Solid-state lithium battery is considered as a promising solution to improve safety performance. However, huge interfacial resistance and polarization between cathode and solid electrolyte are still big challenges for further application. In this study, an improved cathode/Li6.4La3Zr1.4Ta0.6O12 garnet electrolyte interface with low resistance and reduced polarization is successfully constructed by introduced a Li6.4La3Zr1.4Ta0.6O12-C added hybrid PVDF-HFP-based buffer layer. The hybrid buffer layer provides ionic and electronic transport pathways simultaneously at the interface. With the improved interface, the LiFePO4 cathode in the solid-state battery using LLZTO electrolyte displays an increased Li+ diffusion coefficient of 3.42 x 10(-12) cm(2) s(-1) and low charge transfer resistance of 345.2 omega at 1st cycle. The LFP solid-state battery reaches an initial capacity of 152.2 mA h g(-1) and, in particular, displays an outstanding cycle performance with a retention of 84.6% over 200 cycles at 0.5 C and an average columbic efficiency of 99.5%.