# Battery monitoring issues on VOXL2

Source: https://forum.modalai.com/topic/2027/battery-monitoring-issues-on-voxl2
Category: General Questions (https://forum.modalai.com/category/2/general-questions)
Posted: 2023-04-03 07:29:44 UTC by TPSetati
Replies: 7 · Views: 1358

## TPSetati · 2023-04-03 07:29:44 UTC

Good day

Could we please be assisted with out battery monitoring on the VOXL2? We have 2 batteries, and accidently overcharged the one. We were surpriesed to see that QGC was giving a reading of 0%, and only later realized that the drone won't take off because one of the cells was dead. 

We have since stopped using that battery and are using another, but  **voxl-inspect-battery** on the VOXL2 still reads 0%, although we can  fully charge this battery and fly around with just fine. 

What could the issue be here, and how could we remedy this battery monitoring issue?

## Reply by Chad Sweet (ModalAI staff) · 2023-04-04 05:28:14 UTC

What does PX4 / QGC say your battery voltage is? Are you using the APM to monitor voltage and current? We haven't had any issues on our end with battery monitoring

## Reply by TPSetati · 2023-04-04 07:15:15 UTC

**voxl-inspect-battery** gives
![Screenshot from 2023-04-04 09-14-33.png](https://forum.modalai.com/assets/uploads/files/1680592485165-screenshot-from-2023-04-04-09-14-33.png)

## Reply by TPSetati · 2023-04-06 11:00:02 UTC

Good day

Does anyone have any idea what the issue here could be? Because the battery % will not show, QGC won't give us any information about the current battery level.

![Screenshot from 2023-04-06 11-33-57.png](https://forum.modalai.com/assets/uploads/files/1680778625758-screenshot-from-2023-04-06-11-33-57.png) 

Not long ago, I was running some offboard mode test code to autonomously "fly" the drone with the propellers off. While the code was running, everything just stopped without warning, but the onboard PC and GPS module were still on. Unplugging the replugging the battery revealed that the battery is probably low. If we were flying-flying, this could have been an incident.

Any assistance as to why the drone won't read the battery state and send it to QGC will be appreciated.

## Reply by Eric Katzfey (ModalAI staff) · 2023-04-06 18:57:40 UTC (in reply to TPSetati)

@TPSetati What is in the Mavlink messages going to QGC? Take a look at the Mavlink inspector tool.

## Reply by TPSetati · 2023-04-10 08:12:45 UTC

I have just charged my battery and this is the info from the MAVLINK Inspector Tool
![Screenshot from 2023-04-10 10-10-22.png](https://forum.modalai.com/assets/uploads/files/1681114267475-screenshot-from-2023-04-10-10-10-22.png)

## Reply by Eric Katzfey (ModalAI staff) · 2023-04-10 15:55:00 UTC (in reply to TPSetati)

@TPSetati This is showing that you have a 4 cell battery with each cell at 3.125V which is pretty dead. Do you really have a 3 cell battery?

## Reply by TPSetati · 2023-04-11 07:50:58 UTC

I have a 3 cell battery.  I just looked at the vehicle settings in QGC and I see that the battery settings were set to the 4 cells. I changed it accordingly and the battery percentage now reads an acceptible 94%. 

Thank you.