The modern research reported the simplest low-cost synthesis of Bismuth-Copper oxide (Bi2CuO4) with spruce-leaf-like morphology and its applications in supercapacitor devices. Bi (NO3)3.5H2O was used as a precursor during an electrodeposition (ED) process to create the spruce-leaf-like Bi2CuO4 nanomaterial. XRD, XPS, FE-SEM, EDX, and TEM were used to characterize the structures and morphologies of the synthesized materials, while CV, CP, and EIS were used to determine their electrochemical characteristics. The Bi2CuO4 phase was confirmed by XRD patterns, and electrochemical testing demonstrated that the material had better rate capability and an SC of 431.2 F/g at a scan rate of 2 mV/s. After 5,000 cycles, it retained 81.4 % of its energy. Additionally, the maximum SC that was attained by the created asymmetric solid-state device ASSD (Bi0.6Vǀǀ1M PVA-KOHǀǀAC) was 73.7 F/g. The energy density was 55.3 Wh/Kg at a power density of 4570 W/Kg. The exceptional electrochemical performance of Bi2CuO4 thin film electrodes recommends it as a promising material.