The smaller the internal resistance of all batteries is, the better. The smaller the internal resistance is, the stronger the large current discharge capacity is, and the more sufficient the electric energy is released.

Any power supply has more or less a certain internal resistance. In order to improve the load carrying capacity, we hope that the smaller the internal resistance of the power supply is, the better.

The internal resistance of the battery will increase with the increase of the service time, especially for the batteries that are about to be scrapped, the internal resistance will increase significantly. At this time, although the battery voltage is high after being fully charged, the internal resistance will become larger. Once a large current load is connected, a large voltage drop will be generated on the internal resistance, thus reducing the voltage at both ends of the load.