My Macbook Pro M2, bought in 2022, has started to shut down on random when on battery power. Mostly I've noticed that it happens after I wake up my Mac from sleep. I've already taken my Mac to AASP and they ran diagnostics, and nothing came out as particularly faulty.
MacBook Pro 13″, macOS 14.6
Try running the third party app EtreCheck and posting the complete report here so we can examine it for possible clues.
The next time this problem occurs, try running the following command to retrieve some power related information for the time of the incident. This is only an example template where you will need to replace "yyyy-mm-dd" with the actual year, month, day of the event so you can limit the output to only that day in order to make it easier to locate the time period of the event.
pmset -g log | grep 'yyyy-mm-dd'
For example, to filter for events from Aug. 16, 2024, the command would be:
pmset -g log | grep '2024-08-16'
Macbook Pro M2 shuts down randomly on battery.