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Glossary

Glossary · 用語

Trickle charging.

Trickle charging is feeding a small continuous current to a fully charged battery to compensate for self-discharge. Modern MacBooks don’t trickle-charge — once the cell is full, charging stops, and resumes only when capacity drops several percent.

Old laptops trickle-charged continuously, which contributed measurably to battery wear over years of always-plugged use. Apple’s charge controller cuts charging at the top of the curve and waits for natural drop before resuming.

That waiting window is why a plugged-in MacBook routinely shows “Not Charging” at 96–100% even with the adapter connected. The behavior is intentional. It’s also why Optimized Battery Charging can extend the window deliberately — once you’re near full, the system is already holding by default.