Lithium/sulfur polymer batteries(LSPB) consist of sulfur composite cathode, electrolyte and lithium anode. We made a gel type electrolyte of PEO polymer with tetraglyme (Tetra ethylene glycol dimethyl ether) as a plasticizer. The ionic conductivity of polymer electrolyte is $1.42\times10^{-4}S/cm$ and it’s electrochemical stable window is 0.7-4V. The OCV(open circuit voltage) of LSPB is 2.5V, so the gel type polymer electrolyte is appropriate for LSPB. The interfacial resistance between polymer electrolyte and lithium metal doesn’t increase after 500 hours in use. We made composite cathode slurry by using a sublimed sulfur, a carbon black, a PEO, an acetonitrile and $LiClO_4$. Apparent viscosity of composite cathode slurry made by attrition mill approaches a constant value in 6 hours. The sulfur is well-dispersed in composite cathode. S30 (S/PEO/Carbon black=30/35/35wt%), S40 (S/PEO/CB=40/35/25wt%) have a higher specific capacity than S50 (S/PEO/Carbon black=50/35/15wt%), S60 (S/PEO/Carbon black=60/35/5wt%) do, and good cyclability. S30 and S40 shows a low interfacial resistance with electrolyte and high mobility of ions. Redox reactions for S30 and S40 are more reversible than those for S50 and S60. Although the composition of cathode is same, discharge capacity decreases at a high current rate and, the redox reaction is difficult at a high scan rate in CV experiment.
