For a long time, many smartphone users have deliberately avoided fast charging due to concerns that it would damage battery life. However, a long-term test conducted by the YouTube channel HTX Studio, lasting 167 days and covering 500 complete charging cycles, provides a clear answer: fast charging has a negligible impact on battery capacity, and ordinary users need not worry about it.
CNMO noted that the test used six iPhone 12 phones and six iQOO 7 (Android) phones, dividing them into three groups: one group was always charged at 120W high speed, the second group was charged at a maximum of 18W normal speed, and the third group was gently charged following the "30-80%" rule (keeping the battery level between 30% and 80%).
After 500 cycles, equivalent to about a year and a half of normal use, the data showed:
On iPhones, fast charging only resulted in a 0.5% greater capacity loss than slow charging;
Does fast charging damage phone batteries? Six-month real-world test results: battery degradation difference less than 1%
On Android phones, this difference was even less, only 0.3%.
This means that in real-world use, fast charging has virtually no noticeable impact on battery health. In contrast, consistently charging between 30-80% can slightly extend battery life (iPhones retain about 4% more capacity, and Android phones about 2.5%), but this gain is not worth the change in charging habits for most users.
The report points out that battery life only significantly decreases when battery capacity drops below about 85%; if the capacity is below 80%, battery replacement is recommended. However, modern smartphones automatically reduce performance as the battery ages to prevent unexpected shutdowns.
CNMO believes that everyone can choose their charging method according to their own lifestyle and doesn't need to worry excessively about fast charging damaging the battery. Whether it's slow charging overnight or quick top-ups, the long-term impact on the battery is far less than many people imagine.
