What is the internal resistance of a 9V battery?

AndyGadget8 years ago
There's a technique described HERE which involves measuring the battery voltage off-load and then on-load. From the voltage measurements and the load resistor you can calculate the internal resistance, although this is an approximation as the internal resistance is not linear with current drawn.

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Dr.Bill7 years ago
Neroku8 years ago
It depends on the load you connect, the battery chemicals, charge and temperature (the internal resistance will increase when the battery gets hot). But you can find out the internal resistance of a 9v battery for a particular load.