Does fast charging really hurt the iPhone battery see?

For Apple phones, fast charging is only supported on iPhone 8 and above models, but except for the iPhone 11 Pro series, the standard charger for other models is still the ancestral 5V/1A specification, and the power is not even half of the fast charging. Many users say that battery life decreases faster than before after using a fast charging adapter, does fast charging have an effect on iPhone batteries?

In principle, the damage to the battery basically comes from two aspects: on the one hand, when the battery is charging and discharging, the cathode and anode of the battery will shrink and expand with the release and absorption of ions, and prolonged fast charging will destroy the chemicals on the battery, resulting in a shorter battery life.

On the other hand, when fast charging, due to the relatively high current, the thermal effect of the current will be intensified, resulting in high temperature of the battery will be produced, high temperature will also make the capacity plummet and the phenomenon of permanent damage to the battery cell.

The fact is that battery life decreases whenever you're in a state of charge, whether it's regular charging or fast charging, except that the damage is minimal and it takes up to a year or more for it to show on your phone.

Moreover, the impact on the battery is irreversible, whether it is fast charging or normal charging, only that the damage of fast charging will be slightly stronger than the normal charging state. But from the current fast charging technology under various guarantees, this battery damage is still in a safe and reasonable state.

No company offering fast charging solutions is immune to this problem, and for the iPhone, a battery that lasts more than 80% after 500 charge/discharge cycles is normal.