How do I set a battery charge limit, and why does it ask for my password?
Turn on “Limit Charging” in Settings → Battery and pick a level from 50% to 100%. Stopping the charger needs a small background helper with system rights, so macOS asks for your administrator password once, when it's installed.
Good to know
Related options: “Sailing Mode” (lets the level drift a few points before charging again), “Automatic Discharge” and “Top Up to 100%” for a trip.
“Remove Charge Helper” restores normal charging and removes the helper. Uninstalling Notchy removes it too.
Status “Not supported on this Mac” means your model doesn't expose charge control.
See also
Updated
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