In this work, cobalt copper phosphate thin films with a range of Co/Cu compositions are synthesized on a stainless steel (SS) substrate through a simple hydrothermal technique to be utilized as binder-free cathode electrodes in a hybrid supercapacitor. In contrast to conventional asymmetric supercapacitors, the cobalt copper phosphate thin film used as the cathode and reduced graphene oxide (rGO) used as the anode in the aqueous/all-solid-state design offers a wide working potential window of 1.6 V. The aqueous asymmetric device had a maximum specific capacitance of 128 F g-1 at a current density of 1 A g-1 and a power density of 1.65 kW kg-1, and it had an energy density of 45.7 Wh kg-1 and a power density of 1.65 kW kg-1. This is in addition to having an energy density of 45.7 Wh kg-1 and a power density of 1.65 kW kg-1. Furthermore, in a polymer gel (PVA-KOH) electrolyte, asymmetric supercapacitor device seems to have a specific capacitance of 37 F g-1 at 1 A g-1, an energy density of 13.3 Wh kg-1, and a power density of 1.64 kW kg-1, all of which are significant improvements above previous findings. In addition to its long cyclic life (87 and 84 percent after 6000 cycles, respectively), the solid-state device’s practical demonstration (the lighting of an LED lamp) suggests that cathode materials may be used to develop stable energy storage devices with high energy density in the future. This discovery paves the way for further research into phosphate-based materials, as a new class of supercapacitor materials, particularly in light of global warming is challenges.