How to know that battery is needed to be replaced?

I am using Climate module and I know that battery level is 3,19V at this moment. I know that it is OK, because batteries are used for 3 days… :wink: BUT… which value is not OK? I understand that it is also depends on powered devices (modules, tags…) but is there any value when I need to be notified that batteries will be uncharged soon?

I would like to be to notified before whole module die.

We suggest to do not use batteries when the single cell has under 1 V.
So for Mini battery it is 2 V, for Battery Module it is 4 V.

It can work longer in some cases, but it depends on all other modules connected. Some like Lora or CO2 have bigger current spikes which can lead to cyclic resets of the modules.

Great, thank you very much!

Here’s similar thread