Mooncatt
Ambassador
- Feb 23, 2011
- 11,063
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Leaving your phone in does nothing. All these battery myths are persistent but they're still myths. There are redundant safety systems at the battery, port and brick levels while charging your phone. They control how much charge is going to your phone, control heat and stop charging after a certain point. I have been leaving my phones plugged in overnight since 2013, and I've never run into decreased battery life or performance on any phone I've ever owned.
It's not so much that someone keeps their phone plugged in that causes damage. You are right that the devices I'll the charging when it's full, but it's the mere fact that the battery is at a high voltage that harms it. If you fully charged the battery and shelved it disconnected, it'd still cause added stress and wear down.