Redox-active organic materials have shown great potential as electrodes in lithium-ion batteries (LIBs). However, most of them showed a low discharge potential. We report a thianthrene-based small molecule (BDBDT), which could be facilely synthesized, as a high-potential cathode. The BDBDT cathode exhibited good electrochemical performance with a discharge plateau at 3.9 V (vs. Li/Li+) and a discharge capacity of 63 mA h g-1 after 100 cycles at 500 mA g-1 (∼10C). Our results demonstrate that thianthrene-based molecules are promising for the development of high-potential organic electrodes towards rechargeable batteries with high energy and power density.