The internal resistance of all batteries is the smaller the better, the smaller the internal resistance,

the stronger the large current discharge capacity, the more adequate the release of electric energy.

Any power supply has more or less a certain internal resistance, in order to improve the load capacity,

we hope that the internal resistance of the power supply is as small as possible.

In the figure above, the resistance r is the internal resistance of the car battery, and RL is the load,

which is in series with the internal resistance r, and the current flowing through r is equal to the load

current. Assuming that the size of r is unchanged, the greater the load current, the greater the current flowing

through the internal resistance r, the higher the voltage at both ends of r, so that the voltage added to both ends

of the load RL is reduced, if the pressure drop on the internal resistance is too large, and even lead to RL can not

obtain the rated operating voltage and can not work normally, so we hope that the internal resistance of the battery

as small as possible, so that when driving heavy load, There is no significant pressure drop on the internal resistance.

The internal resistance of the battery will increase with the growth of the use of time, especially the fast scrapped battery,

the internal resistance increases significantly, although the battery voltage is higher after full charge, but because the internal

resistance becomes larger, a large current load is connected, the internal resistance will produce a larger voltage drop, so that

the voltage at both ends of the load is reduced.