Transition metal phosphate (TMP) based materials are developing as advanced type electrode materials for hybrid supercapacitors (SCs) due to their unprecedented conductivity, and rich redox activity. Attracted by these fabulous physicochemical characteristics of metal phosphates, binder-free nickel copper (Ni-Cu) phosphate thin films with Ni-Cu composition variation were directly grown on stainless steel (SS) substrate via hydrothermal and SILAR methods. The composition of nickel and copper ratio varied to achieve better results by using synergy among them. Binder-free and adherent thin films of nickel copper phosphate were characterized by various physico-chemical methods. The best performing nickel copper phosphate electrodes were used for the fabrication of asymmetric (Ni-Cu Phosphate//rGO) aqueous (1 M KOH electrolyte) and solid state device (SSD) (PVA-KOH gel electrolyte). Moreover, SSD brightens a panel of 201 red light-emitting diodes (LEDs) illustrating its commercial practicability to next-generation hybrid energy storage devices.