I'm helping one on of my students measure the power output of a battery. We
load the battery with a 10 ohm resistor across its terminals and measure the
current through the resistor and the voltage across the resistor. This works
fine for the AA, AAA, C, and D size batteries. But the button cell
batteries, for watches, give a decaying current. Any ideas as to how I can
alter my measurement method to get a steady current from the button cell
batteries?