Journal · 日誌
Field notes on MacBook batteries.Long-form guides, plainly written.
The longer reads from Battery Sensei. Each post is researched from Apple’s own documentation, independent cycling tests, and the way real MacBooks behave day to day. No vendor jargon, no affiliate links — just the answers we’d give a friend.
8 min read
Should I keep my MacBook plugged in all the time?
What actually happens to a MacBook battery when it lives at 100% — and the three macOS settings that change the answer. Plain English, Apple sources cited.
Read post9 min read
Optimized Battery Charging on Mac, explained — and where it falls short
Apple's OBC uses on-device ML to delay charging past 80%. Here's how it actually works, where it falls short, and what to do about the gaps.
Read post9 min read
MacBook battery cycle count: what's healthy at every age
Modern MacBooks are rated for 1,000 cycles. Here is what normal looks like at one year, two years, and four years — and when "Service Recommended" actually means it.
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Need a quick reference rather than a long read? The glossary defines the vocabulary that comes up across these posts — cycle count, optimized battery charging, calibration, and so on.