Typical USB phone path: try 80–95. Lower if cable/adapter is weak or device is hot.
Idealized estimate: capacity (mAh) ÷ (average charge current in mA × efficiency %). Not a lab measurement.
Typical USB phone path: try 80–95. Lower if cable/adapter is weak or device is hot.
A simplified constant-current style duration: mAh divided by effective mA (current × efficiency). Real lithium charging spends time in CV taper, so actual wall-clock time is often longer.
Phones reduce current when warm, near full, or on a weak cable. Advertised “max” mA is rarely sustained for the whole cycle.
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No. This is an educational rough estimate only.
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