The LiS-based cathodes to couple with Li-free anodes are regarded as a commercially available approach to overcome the safety risk of lithium metal anodes. However, the passivated LiS instinct leads to a high activation potential in the initial charging process, and the notorious shuttle effect of polysulfide is inevitable upon cell cycling. Here we create a single atom tailoring strategy by comproportionation reactions (LiS + 1/8S = LiS) to form the LiS materials without any complex manufacturing process or additives, where the LiS cell enables a lower potential barrier and allows for the 3.0 V activation voltage without any other material modification. Meanwhile, the polar conducting material TaB is introduced to restrain the migration of polysulfides, and provide fast redox reaction kinetics. With those ingenious tailoring of cell designs, the LiS-TaB cell (LiS: 88 wt%) exhibits high areal capacity (4.6 mAh/cm at 6.0 mg/cm LiS loading), excellent cycling stability (500 cycles at 1.6 mA/cm).