Does anybody know the approximate inner resistance range of a car battery? Google came back with various different answers.
Let’s say, it’s 10milliOhms, then if I put 100A load on it, voltage should drop by 1V. In this example from 12.4V to 11.4V. (no alternator running)
Is my thinking correct?
Yup, that's about right.
Flooded lead acid batteries are chemical devices, so internal resistance can probably vary, depending on the particular chemistry, materials used, and internal construction. It will actually be reflected in the "CCA" rating of the battery. Lower resistance = more cranking amps.
But yes in the milliohm range. Why do you ask?
https://batteryuniversity.com/article/bu-902-how-to-measure-internal-resistance
https://batteryuniversity.com/article/bu-802a-how-does-rising-internal-resistance-affect-performance
