Herein, Ni0.8Co0.15Al0.05(OH)₂ materials, a by-product in the preparation of the precursor of cathode materials for lithium ion batteries, were employed as supercapacitor electrodes. The reaction time was changed from 2 to 48 h to produce hydroxide products, which were analyzed using physical and electrochemical methods. The hydroxide material reacted for 2 h exhibited a good average particle strength of 34.3 MPa with a particle size of 7 μm. When used as a supercapacitor electrode, the 2 h-reacted hydroxide electrode presented a high capacitance of 244.7 F g-1 at a current density of 0.5 A g-1 with a typical pseudocapacitive behavior, indicative of a highly suitable supercapacitor electrode material.