Estimating battery life of device using AAA battery


#1

Hello,

I would like to use the Otii to estimate the battery life of a device that uses an AAA battery.

We know that battery life will be at least several months on our device, but we would like the test estimating battery life to take less than an hour. So we need a method of collecting data along an AAA discharge curve and estimating battery life based on that information without running the Otii for months.

Is there a way to access the AAA discharge curve (available as a power supply with the premium license) through the scripting API? If not, is there another approach to this that could accomplish this goal?

Thank you for your help!


#2

Hi,

Yes, this is possible to script.
First, I recommend that you get the list of your battery profiles:
device:get_supplies()
Then you identify the correct battery profile ID and set it as supply:
device:set_supply(id)
You can the iterate by setting used capacity with an increasing number (capacity in coulombs, multiply mAh by 3.6 to get C) :
device:set_supply_used_capacity(capacity)
Then you monitor the voltage and detect if you drops below your device cut-off voltage. Make sure you measure a period with your highest consumption.
If you reach your cut-off voltage, then you know how much of your battery’s capacity that you will be able to use.
If you do not reach you cut-off voltage you increase the capacity and test again.

When you know how much capacity that are available for your device to use, then you can calculate the battery life time of your device.

Remember that your battery capacity also depends on your environment, like temperature, so you must have a battery profile that take this into consideration.

I hope this helps you out!

Best regards,
Björn


#3

Thank you, Bjorn!