A lithium-ion capacitor may include a cathode, an anode, a separator disposed between the cathode and the anode, a lithium composite material, and an electrolyte solution. The cathode and anode may be non-porous. The lithium composite material comprises a core of lithium metal and a coating of a complex lithium salt that encapsulates the core. In use, the complex lithium salt may dissolve into and constitute a portion of the electrolyte solution.