Combine your device’s sleep and active states into a repeating profile — same load the battery would see in the field. You can set constant current, constant power, or constant resistance for each step.

For a typical low-power IoT device that wakes briefly to transmit: a short active step at [your active current] mA followed by a long sleep step at [your sleep current] µA, repeated. Accelerate the discharge if needed, by adjusting the time and level of activity.

Connect the battery, set the cutoff voltage, and start the run. Otii captures voltage, current, and capacity at microsecond resolution from full charge to your cutoff.

Depending on the battery and your load, this takes anywhere from a couple of hours to a couple of weeks — but you only have to do it once per battery model (and temperature if you using temperature chamber) .

The completed run becomes a battery profile artifact: voltage curve, capacity, internal resistance characteristics, and the discharge conditions you used. Save it and it’s available across your team.

The same profile is what the Battery Life Estimator uses, so this one measurement powers two workflows. Manage you battery profiles in Battery Profile Management.

Now switch your Otii box from measurement mode to emulation mode and load the profile. The Otii acts as that battery — same voltage curve, same internal resistance, same behaviour as the discharge proceeds.

Two emulation modes: Fixed holds the battery at a single point on the curve (useful for low-battery edge-case testing); Follow plays out the full discharge so your device sees what it would see in real life.