Clarence is concerned about the new trend to have irreplaceable batteries in devices, like the new Nintendo Switch. Leo says that iFixIt says the battery in the Switch can be replaced with the right tool and replacement part. It's doable. But there's no user serviceable part for the battery in the iPhone. It's all glued in now. Apple will repair a battery for you, but it can't be done by the user. Clarence's battery should last around 500 complete charges. Once that happens, they are dead.
Clarence is wondering if it can be overcharged. Leo says no. There's circuitry designed to keep it from overcharging. He just should make sure not to completely drain the phone. In general, he should keep it plugged in when he's not mobile. He shouldn't let the phone drain unnecessarily.
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