Abstract: The urgent need for high-performance energy storage devices makes lithium-sulfur batteries (LSBs) with theoretical energy densities up to 2600 W·h/kg very attractive. However, the low capacity reversibility and the natural defect of sulfur's self-insulating property restrict its commercialization. In order to effectively improve the electrical conductivity of sulfur while suppressing the shuttle effect of polysulfides, the purpose of improving the electrochemical performance of LSBs is achieved. In this paper, a layer-by-layer coating method was used to coat the surface of the expanded graphite (EG)/sulfur (S) composite cathode with fluorinated vapor-deposited carbon fiber (FVGCF). A composite layer of LiF and FVGCF is formed on the surface of the pole piece. The electrochemical performance test and morphological characterization results show that the new cathode material using FVGCF has the best cycle life. The initial discharge specific capacity of EGS-FVGCF at 1 C current density is 691.8 mA h/g, and the remaining specific capacity after 100 cycles is 549.5 mA h/g. Compared with the EGS-coated single-layer structure, the double-layer battery coated with FVGCF on EGS has great application advantages, and the LiF generated during the discharge process can inhibit the shuttle of polysulfides from the positive electrode to the negative electrode. At the same time, the electrode morphology characterization after discharge and charge found that the addition of the FVGCF layer reduced the cracks on the surface of the pole piece, indicating that the FVGCF layer buffered the volume expansion of the sulfur cathode to a certain extent. This simple and easy-to-operate composite structure provides a certain reference for the development of high-performance LSBs.