Method for testing semi-finished battery cell

A method for testing a semi-finished battery cell, the semi-finished battery cell including a first electrode and a second electrode, with said first and second electrodes disposed in a pile, with an insulation layer disposed between the first electrode and the second electrode, with the first electrode electrically connected to a first conductor, and with the second electrode electrically connected to a second conductor, the method comprising:

• charging the semi-finished battery cell with a constant current when a voltage difference between the first conductor and the second conductor is less than a voltage threshold;
• charging the semi-finished battery cell 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;
• obtaining an overall electric quantity 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;
• and
• determining whether the overall electric quantity is larger than an electric quantity threshold, wherein an insulation between the first electrode and the second electrode of the semi-finished battery cell is determined as poor when the overall electric quantity is larger than the electric quantity threshold.