iPhone XR Smart Battery Concerns

[Ian4Mac]

Just got one smart battery case for my iPhone XR from eBay last week.
I noticed that whenever I put the battery case on, my iPhone always shows battery is being charged.
The reviews I read say that iPhone will drain the battery case first, then the internal battery. So the battery case can be helpful to keep the internal battery healthy.
While my experiences are that the battery case keeps on charging the internal battery when possible, and iPhone always withdraw power from the internal battery. Therefore, the internal battery is always being charged and drained simultaneously when the battery case is used, which may not be a good thing.

Any clues? Thanks

 

[Whoakapi]

I don't think that the iPhone (or any iOS device) bypasses the internal battery when plugged in with cable and fully charged. I would assume it's the same situation whether it's connected with a smart case or a cable.

 

[Shadowbech]

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