I have several Rak nodes that are connected to solar. But Ive noticed they only charge the batteries to 4,05volts not 4.2Volts, giving a 90%ish indication in the app.
Anyone else have this “issue”?
i also have several RAK on solar.
as i have observed:
my raks charge up to 4,2V occationally, but then wont recharge until below 90some%
recharge will restart after voltage went below a certain point.
so, very most of the time, even in best sunshine, my rak nodes show something around 89 to 92%
that also depends on the battery a bit, what voltage level it has, when full, but slightly discharging, and not charging…
Same here, never fully charged. Should help keep the battery happier over the long haul.
Here’s a Reddit thread that goes way down the rabbit hole on the topic.
Short answer, it’s all good, and while cell phones have us trained to top off to 100% every night, these are pretty happy running in the 20% - 80% range most of the time. Forcing them to 100% every night is just going to kill the battery life.
Something I just learned was, there’s a non-zero default value for the ADC_MULTIPLIER value under the power settings, specifically for the RAK4631.
It was hidden under that web page’s calculator drop-down, but for the Rak4631’s that value should be 1.73…at least for starters, you may still need to use the calculator tool, though I have not.
Best to all,
Pol
1 Like
I figured it was some kind of battery feature and not a bug as all my Raks do the same. 
I tested it by connecting discharged batteries, and they all charged up to aprox the same Voltage. The extra battery capacity you get from the last 0,2Volts are minimal and will degrade the battery a lot faster if used.
1 Like