The effect of the capacity matchup between cathode and anode in the LiNi0.5Mn1.5O4/Li4Ti5O12 cell system on cycling property, choice of electrolyte, high voltage and overcharge tolerances was investigated by comparing the cells with Li4Ti5O12 limiting capacity with the cells with LiNi0.5Mn1.5O4 limiting capacity. The former exhibits better cycling performance and less limitation of electrolyte choice than the latter. Furthermore, the Li4Ti5O12-limited cell exhibits better tolerance to high voltage and overcharge than the LiNi0.5Mn1.5O4-limited cell, owing to taking advantage of the extra capacity of Li4Ti5O12 below 1V. It is thus recommended that the LiNi0.5Mn1.5O4/Li4Ti5O12 cell whose capacity is limited by Li4Ti5O12 anode should be used to extend the application of the state-of-the-art lithium-ion batteries.