Selenium attracts increasing attention as cathode material for rechargeable lithium batteries due to its high conductivity and comparable volumetric capacity with sulfur.Microporous carbon spheres(Mi PCS) are synthesized via a hydrothermal-annealing route followed by activation with KOH. The Mi PCS are used as matrix for Se loading to form Se/Mi PCS composite. Such composite delivers a high specific capacity close to the theoretical value of Se. In carbonate-based electrolyte, the capacity is as high as 733 m Ah g-1at a current density of 50 m A g-1, and 353 m Ah g-1 at 5000 m A g-1. At 0.5 C, the capacity retains up to 515 m Ah g-1even after 100 cycles. Such outstanding electrochemical performance of the composite cathode in the carbonate electrolyte can be ascribed to the robust structure of Mi PCS and to the'solid-solid' electrode process.
