Lithium-ion batteries don’t age well.

If you leave your MacBook, MacBook Pro, or MacBook Air plugged in all the time—no matter the vintage—the battery suffers wear for being charged to full. Over time, the maximum charged capacity diminishes and you lose many minutes—even hours—of usable time. It is just a characteristic of the lithium-ion batteries in laptops and nearly all modern electronics.

Here is a quick list of the best practices for managing your MacBook’s battery.

• Routinely unplug your laptop, as frequently as daily, and let it drop its power down to the 30 to 40 percent range.
• Don’t fully discharge your battery regularly—that is, don’t let it run down to zero. As Battery University (not a degree-granting institution) notes, “If at all possible, avoid full discharges and charge the battery more often between uses.…There is no memory and the battery does not need periodic full discharge cycles to prolong life.”

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Read full post here:
https://www.macworld.com/article/3564563/dont-keep-your-mac-laptop-charged-to-100-percent-all-the-time-heres-why.html