Hybrid supercapacitors integrated rice husk based activated carbon with LiMn2O4

The technology development of supercapacitor is in the progress to meet the strong demands for increasing specific energy and reducing cost. We present a hybrid supercapacitor that integrated rice husk based activated carbon (RHC) with LiMn2O4. The electrochemical investigations revealed that the specific energy of the hybrid supercapacitor (LiMn2O4/RHC) has reached up to 29.5 W h kg−1, and the energy retention is 81.2% over 10 000 cycles at 0.3 A·g−1 charge/discharge current. The excellent double layer electrical storage of the RHC is mainly attributed to its high specific surface area of 2516 m2 g−1 and the average pore diameter of 3.02 nm.