There is some online discussion of battery drain occurring overnight on MacBook Pro and MacBook Air laptops, while the Macs are in sleep mode, with many users noticing the problem after updating to a recent version of macOS Monterey.
While there does seem to be an uptick of overnight battery draining behavior with macOS Monterey 12.2, the particular issue has actually predated macOS Monterey. As we covered in October of last year prior to Monterey’s release, we noted similar overnight battery drain was happening with later macOS Big Sur updates to some Mac laptop users.
Fortunately there’s a simple solution available now, and that is updating macOS Monterey. And if you’re experiencing the issue on a Mac before Monterey, disabling bluetooth may resolve the battery draining while sleep issue.