A hybrid electrolyte energy storage system combining the features of supercapacitors and lithium batteries has been constructed. It consists of MnO 2 nanoflakes in 1M Li 2 SO 4 aqueous electrolyte as the cathode and lithium foil in ionic liquid (1M lithium bis(trifluoromethanesulfonyl)imide (LiNTf 2 ) in N-methyl-N-propyl pyrrolidinium bis(trifluoromethanesulfonyl)imide ([C 3 mpyr][NTf 2 ])) electrolyte as the anode, separated by a lithium super ionic conductor glass ceramic film (LiSICON). This system shows the advantages of both a supercapacitor (long cycle life) and a lithium battery (high energy), as well as low cost and improved safety due to the combination of ionic liquid and ceramic solid state electrolyte in lithium side, which can reduce the formation and prevent the penetration of lithium dendrites. The specific energy for the cathode materials in the hybrid electrolyte system is 170Whkg −1 with more than 85% retention up to 2400cycles. This system is a great candidate for stationary batteries storing solar and wind energy.