Happy new year to all flyers. 

We want to update the progress made on an in-flight battery monitor. Initial revisions of the board were meant to capture accurate cell voltages for the flight batteries. However, lot of feedback was received to push the board towards a minimal Battery Monitoring System. Currently, most diy'ers and professional flyers use large battery packs after monitoring them with an external battery meter. We believe its advantageous to semi-permanently attach the monitor with the batteries as Batmon has cell balancing and minimal weight/power penalty. 

The features of Batmon are: 

  1. Inbuilt Coulomb counting for accurate power draw (and hence power remaining) for the cells
  2. Accurate monitoring of individual cell voltage ( precise to 50mV or better) 
  3. Onboard temperature monitoring + extra optional temperature probes for accurate measurement of battery temperature in harsh weather.
  4. 9gm weight 
  5. Connects to Pixhawk i2c bus with stock firmware to read total battery voltage, temperature, current. Custom pixhawk firmware enables monitoring cell voltages and many other battery parameters.
  6. Low current onboard cell balancing. 
  7. Switchable low-power led display for convenient display of battery vitals (~3mA / 40V with display on)

Batmon battery monitor measuring 10s

3689737355?profile=original9gm board

Would love to get feedback. We will build ~100 boards end of March,2019. Please PM me for feedback/pre-orders.

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  • We have launched the online store for batmon at rotoye.com now

    Smartify the battery
  • @duncan, Sure. Please PM for more details.

  • @echo G. Very interested in this. Do you have a website or any other data?

  • @Francis, we haven't tested with solo, but since it's using pixhawk, it should be.

  • Great development! Will it be possible to use with "normal" batteries on the 3DR Solo?

  • We didn't have enquiry for lower than 6s batteries. But can make 4s versions if there is enough interest.
  • I noticed that it says that you can only use it for 6-10s batteries. Will there be a chance that it could also monitor lower battery voltages like 4s?

  • @Evan, there is hardware and module support for reading cell voltages. There is just some minor aspects that have to be changed, which can be shared if you are interested.
  • @Andreas, the screen adds 4gm to board. But yes, there is a version without the screen.
    Please PM me your requirement.
  • Regarding Point #5:
    This is using SMBus to communicate with the flight controller, if I am not mistaken. ArduPilot does support cell voltage readings over SMBus (originally intended for SBS 1.1 batteries). Is there information available as to what firmware changes are required? Or are such changes only needed for PX4 firmware?

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