CR2032 battery measurement event

[Jingar]

Hello !!

          My hardware is based on IOT application. I'm using nRF52833 SOC as end node and powered it through CR2032 coin cell. In system ON phase ( sleep mode) it is consuming around 3.5 uA while during On condition (Run mode) it is consuming average 3 mA.

          At which time should I have to measure battery voltage ? When system is just turned On or during Bluetooth event (advertising, connecting or data transfer) ?

          What is the general practice for measuring coil cell voltage in low power application ?

           My final goal is to represent accurate battery SOC based on voltage measurement. It is okay if there is an error of  5 % to 10 % in SOC value indication.

[awneil]

It's a bit confusing to use "SOC" with 2 different meanings!

If you measure the voltage immediately after waking up from sleep, the battery will be "rested" - so you'll get an unrepresentatively high value.

If you measure the voltage during the radio Tx or RX, that will be at the point of maximum power drain - so you may get an unrepresentatively low value

Besides all of which:

Jingar said:

My final goal is to represent accurate battery SOC based on voltage measurement

but that's a fundamentally flawed approach:  voltage measurement is a rather poor indicator of state-of-charge - especially for lithium batteries!

There's a lot of research been done on this - it's not specific to Nordic - so some googling should get you general information ...

[Jingar]

Thanks for response. I will try to get info from google.