High Energy Density and Stable Three‐Dimensionally Structured Se‐Loaded Bicontinuous Porous Carbon Battery Electrodes

3D‐structured Se‐loaded bicontinuous porous carbon (BPC) electrodes are fabricated through colloidal templating of BPC followed by pulsed‐voltage Se electrodeposition. The resultant electrodes are found to deliver a specific capacity of 665 mAh g −1 at a rate of 0.1 C, near the theoretical value for Se. When a vinylene carbonate (VC) containing electrolyte is utilized, the capacity fade over 500 cycles at 1 C rate is as small as a few percent. Impedance measurements and physical characterization of cycled electrodes indicate the exceptionally stable cycling performance is possibly due to VC resulting in the formation of a stable solid electrolyte interface (SEI) during cycling. Along with the cycling stability, the rate performance of the 3D Se/BPC electrodes is also good. Due to the bicontinuous structure of carbonaceous current collector at rates as high as 5 C, the deliverable capacity is about 300 mAh g −1 .