Abstract: In one aspect the present disclosure relates to a system for measuring an internal resistance of a battery. The system may involve: a processor; a load module responsive to the processor for applying a load across the battery; a current sense subsystem for sensing the current flowing to the load module and generating a sensed current signal in accordance therewith; a multiplexer module in communication with the current sense subsystem for detecting voltages with the load coupled across the battery and uncoupled from the battery, and generating voltage signals in accordance therewith; and a filtering and amplification subsystem responsive to the multiplexer module, for filtering and amplifying a level of each of the voltage signals to produce modified voltage signals for use by the processor in determining the battery internal resistance.