Manganese dioxide lithium button cells with high energy density and excellent discharge characteristics. They are suitable for various applications such as smart access systems or TPMS (Tire Pressure Monitoring System) for automobiles, IoT devices, and as a backup power source for storage. The active cathode material is specially processed manganese dioxide (MnO2), and the active anode material is high-voltage, highly active lithium metal. The electrolyte is lithium salt melted into an organic solution to ensure easy transfer of high voltage and high energy externally.