This study presents a novel method for preparing bismuth copper oxide (Bi₂CuO₄) electrodes using a binder-free successive ionic layer adsorption and reaction (SILAR) technique, demonstrating their potential for energy storage applications. The Bi₂CuO₄ electrode exhibits a tetragonal crystal structure with a polycrystalline nature, confirmed by X-ray diffraction (XRD). Field emission scanning electron microscopy (FE-SEM) reveals a distinctive sphere-like structure with hydrophilic characteristics. X-ray photoelectron spectroscopy (XPS) confirms the composition of the sample. The electrochemical performance of Bi₂CuO₄ is remarkable, with a specific capacitance (SC) of 1795.9 F/g at 16 mA/cm². When used as an anode in an asymmetric solid-state device (ASSD) alongside activated carbon (AC) as the cathode, the Bi₂CuO₄ electrode attains a maximum energy density (SE) of 169.5 Wh/kg at 16 mA/cm² and a peak power density (SP) of 15.9 kW/kg at 24 mA/cm². In a 1 M KOH-polyvinyl alcohol (PVA) polymer solution, the Bi₂CuO₄//AC pencil-type cell achieves a superior SC of 94.5 F/g at 5 mV/s, retaining approximately 92% of its initial performance even after 5000 charge–discharge cycles. The resulting SE and SP are 43.1 Wh/kg and 5.2 kW/kg at 10 mA/cm², respectively. This research presents an efficient and straightforward synthesis method for producing high-performance pencil-type supercapacitors at a laboratory scale. Furthermore, we demonstrate the potential of a homemade pencil-type supercapacitor device (Bi₂CuO₄//AC) to power a light-emitting diode (LED), highlighting its practical utility in various energy storage applications. The study highlights the importance of finding cost-effective alternatives to expensive materials like RuO₂ for energy storage applications. The Bi₂CuO₄ electrode is synthesized using the SILAR method on a copper substrate, and its electrochemical characteristics are investigated. The study also reports the successful synthesis of Bi₂CuO₄ thin films using various methods, including electrodeposition and solvothermal techniques. The results show that Bi₂CuO₄ has excellent electrochemical performance, making it a promising candidate for energy storage applications.This study presents a novel method for preparing bismuth copper oxide (Bi₂CuO₄) electrodes using a binder-free successive ionic layer adsorption and reaction (SILAR) technique, demonstrating their potential for energy storage applications. The Bi₂CuO₄ electrode exhibits a tetragonal crystal structure with a polycrystalline nature, confirmed by X-ray diffraction (XRD). Field emission scanning electron microscopy (FE-SEM) reveals a distinctive sphere-like structure with hydrophilic characteristics. X-ray photoelectron spectroscopy (XPS) confirms the composition of the sample. The electrochemical performance of Bi₂CuO₄ is remarkable, with a specific capacitance (SC) of 1795.9 F/g at 16 mA/cm². When used as an anode in an asymmetric solid-state device (ASSD) alongside activated carbon (AC) as the cathode, the Bi₂CuO₄ electrode attains a maximum energy density (SE) of 169.5 Wh/kg at 16 mA/cm² and a peak power density (SP) of 15.9 kW/kg at 24 mA/cm². In a 1 M KOH-polyvinyl alcohol (PVA) polymer solution, the Bi₂CuO₄//AC pencil-type cell achieves a superior SC of 94.5 F/g at 5 mV/s, retaining approximately 92% of its initial performance even after 5000 charge–discharge cycles. The resulting SE and SP are 43.1 Wh/kg and 5.2 kW/kg at 10 mA/cm², respectively. This research presents an efficient and straightforward synthesis method for producing high-performance pencil-type supercapacitors at a laboratory scale. Furthermore, we demonstrate the potential of a homemade pencil-type supercapacitor device (Bi₂CuO₄//AC) to power a light-emitting diode (LED), highlighting its practical utility in various energy storage applications. The study highlights the importance of finding cost-effective alternatives to expensive materials like RuO₂ for energy storage applications. The Bi₂CuO₄ electrode is synthesized using the SILAR method on a copper substrate, and its electrochemical characteristics are investigated. The study also reports the successful synthesis of Bi₂CuO₄ thin films using various methods, including electrodeposition and solvothermal techniques. The results show that Bi₂CuO₄ has excellent electrochemical performance, making it a promising candidate for energy storage applications.