Spinel NiCo 2 X 4 (X = O or S), comprising two geometrical cobalt ions, Co 2+ in the tetrahedral site (Co 2+Td ) and Co 3+ in the octahedral site (Co 3+Oh ), has been widely evaluated as a promising pseudocapacitor electrode material. Previous literature mainly demonstrated that much higher specific capacitance of NiCo 2 S 4 than that of NiCo 2 O 4 was ascribed to the higher electronic conductivity. However, we argue that only a small amount of capacitance can be induced by the electronic conductivity, while the significance of electrochemical active species in these system has long been ignored. Here, we propose that geometrical-site-dependent pseudocapacitive activity will generate enhanced specific capacitance through the interface structural design. It reveals that specific capacitance of NiCo 2 S 4 (1862 F g -1 at 4 A g -1 ) is 50% higher than that of NiCo 2 O 4 (1230 F g -1 at 4 A g -1 ), which is derived from the designed increase of Co 2+Td ions (cobalt ions in the tetrahedral site) in NiCo 2 S 4 . These results have significant implications for the design and optimization of the electrochemical properties of transition-metal-based pseudocapacitors.