Dash.batteryPercentage() going from 0 to 50 then quickly decreasing

Currently the Dash we are testing sends battery data using Dash.batteryPercentage(). The issue is that after around 3 hours of charging, the Dash reaches 50% and then quickly, at least 1% every 5 minutes, drops back down to 0.

I then tried another battery, which upon plugging in to the Dash, revealed it was 70% charged. This battery was able to make it’s way up to 100% with no issue. I then let that battery drain to test the battery’s time to discharge.

I then charged the battery again, however this time it got to 97% and started to dwindle down while still being plugged in to USB, same as the other battery.

Is this how Dash.batteryPercentage() should work? Do I have a bad batteries/bad Dash?

I’m seeing similar behaviour. I’ve set the jumpers to Battery, attached a 3.7v Lipo as well as the usb cable. I created a simple sketch to wake up every 10 mins and report the battery percentage and millivolts. With one battery, i can watch the percentage and voltage increase to 100% and stay there. With a different battery, I can see the voltage drop over time (although not as fast as yours). I’m thinking it might have something to do with the input voltage and current coming off the usb cable. If it isn’t high enough, the charging stops and it just goes off the battery.

The first battery would die very quickly, but the second battery took about 17 hours to go from 97% to 0%. As far as millivolts, the second battery’s highest point was 4191mV. It stayed at 4191mV for about 20 minutes, then started to drop. After around 17 hours it went to 2565mV. Once it hit 2565mV, the Dash turned off. Note, the Dash was plugged into a micro USB for this whole scenario. Then the Dash would not turn on. I had to remove the battery and reset the jumper to 5V USB to get the Dash to function again.