In this paper, we propose a systematic design procedure to estimate the capacity of battery cells and packs using the incremental capacity analysis. Through Pearson correlation analysis, the peak point of the incremental capacity that is correlated with the battery capacity and the voltage difference size used when calculating the incremental capacity are selected. A regression model for capacity estimation is designed using the incremental capacity of the battery cell, and the battery pack is designed by scaling the cell's regression model parameters to reflect the number of cells in series and parallel. The validity of the proposed method was verified from experimental data of the INR 18650-29E cell and a battery pack with 7 cells connected in series and 20 parallel.