A method is provided for testing a semi-finished battery cell. The semi-finished battery cell is charged with a constant current when a voltage difference between the first conductor and the second conductor is less than a voltage threshold. The semi-finished battery cell is charged with a constant voltage when the voltage difference between the first conductor and the second conductor is equal to or larger than the voltage threshold. An overall electric quantity is obtained after a default time period, wherein the overall electric quantity is an electric quantity charged to the semi-finished battery cell with the constant current during the default time period. Accordingly, an insulation related to electrodes of the semi-finished battery cell is determined as poor when the overall electric quantity is larger than an electric quantity threshold.