What is the Battery Status menu on Mac?
If you’re using a Mac laptop, you can quickly see the status of your battery and find out if an app is using a significant amount of energy.
If you don’t see the battery icon in the menu bar, you need to add it. See Monitor your Mac laptop’s battery.
To view the Battery Status menu, click 
in the menu bar. You can check the following:
The percentage of battery charge.
The current power source.
Whether Low Power or High Power Mode is enabled (if your Mac laptop supports it and if you enabled it in Battery settings).
Whether the battery is fully charged or the amount of time until the battery is full (if your Mac is connected to a power supply). The information may take a few minutes to appear.
Which apps, if any, are using a lot of energy. If an app is using significant energy, but you’re not using it, consider closing the app, particularly if your current power source is the battery on your Mac.
On some Mac laptops, the Display Brightness icon
is shown when the display’s brightness is set to a level that uses a significant amount of energy. To quickly optimise battery usage, click the icon — the display brightness is reduced to approximately 75 per cent.