Device Vital reports "Err:-210", "state:unknown" when plugged into USB? Is this normal?

Why does device vitals show battery charge as err:-210 with state:unknown when plugged into USB host? Looks like it reports the battery percentage properly when running solely on battery but not when plugged in.

When plugged into USB:

{"device":{"power":{"battery":{"charge":{"err":-210},"state":"unknown"},"source":"USB host"}

When on battery only:


I was thinking it should always be able to give me a charge value? I am running a Lipo 6600 mAH from

Thoughts? Was this changed in a recent release of firmware?

Hi @jgskarda - what type of device is this? What version of device OS? Err -210 indicates a disconnected battery (to my understanding), but it seems like your battery is connected and charging? This particular LiPo seems like it might be a little testy when it’s fully charged - does the error message changed when the battery is depleted a bit further?

Hi @marekparticle, the device is a boron LTE running device OS 1.4.2. yes my battery is connected and fully charged or charging when this occurs here is a pictured.

I have a few other 6600 mAh batteries and they all had the same issue. I did try the smaller 1800 mAh and that one reported correctly given a status of "power":{ "battery":{ "charge":100 "state":"charged"} "source":"USB host"

Back to the 6600mAh, as soon as i unplug it then it will report correctly. "power":{ "battery":{ "charge":100 "state":"discharging" }

I guess the 6600mAh is just a little testy when fully charged like you said. All of my batteries are fully charged right now but maybe i’ll keep it running throughout the night with the relay on and see if I can drain it enough to see what happens at a lower charge.

Is there some settings I should change when using the 6600 mAH battery? Also, I’ve wondered, how low can I go on the battery charge level? Do I need to eventually sleep say once it’s < 2% and never wake up to prevent damage to the battery or can I drain those things until the Boron won’t wake up due to lake of power?

@marekparticle, I kept the device powered on with a relay turned on all night. It was able to drain my battery down to 72% or so. Now when I plug it in it will report correctly. "power":{ "battery":{ "charge":73.39 "state":"charging" }So looks like I only get the err:-210 when my 6600 mAh battery is fully charged and has power.

Is there something I should be doing or some charge setting I should change when using 6600mAh battery. I guess I could add logic on my back-end to say if I get err:-210 it’s 100% charged but something just seems wrong with that approach.

-Jeff Skarda

I suspect that the battery is charged higher that the default state of charge limit in the boron

and it explains why when you depleted the cell somewhat - it was in range.

Yeah sounds like it. I never changed any settings or have any code to modify any of the fuel gauge settings therefore a bit surprised it’s put itself in this state. I guess my question to the group is should I be thinking about modifying anything due to using the 6600 mAh lipo battery? As long as I’m not damaging or shortening the life of the battery I think I can live with the ERR:-210 when fully charged and plugged in. Not ideal but manageable. However, If i am shortening the life of my battery then I feel like I should do something about it.


Not having dug into the DeviceOS sources, I would hazard a guess that there is probably an overflow of the voltage reading from the PMIC chip when the battery is higher that its set max charge level. I don’t believe there will be any damage to the battery - however on a battery of that that size, loosing 15% of the max charge level is quite significant in terms of usable power when on battery, so I would look into setting the PMIC charge termination voltage much higher.