I've gotten random battery error warnings with mine, but in every instance, they just go away. I'm not sure if it's something serious, but there's non follow-up in the app or any other direction given as to what to do. I've gotten it probably four times or so in the past two months.
Ive had the same thing. Just briefly comes up batt err and then disappears. Kind of worrisome. I'm new to the mavic and bought mine second hand so not even sure they'd honor the remaining warranty if she decides to go pitch black and nosedive....