Users have long suspected fast-charging hastens iPhone battery drain more than low-power charging, but a new experiment supports Apple’s claim that it doesn’t. At least, not much.
Fast-charging speeds may not drain iPhone battery faster
Over the past several years, iPhone users have debated whether fast-charging the handset with higher-wattage chargers leads to faster battery drain. The question and various answers appear on forums like Apple Discussions, Quora and Reddit.
Now a new experiment supports the commonly held expert advice that fast-charging doesn’t hurt battery health in most cases.
X (formerly Twitter) user @VadimYuryev posted about a test by a MacRumors Forum user. They charged their iPhone 14 using a 5W charger while their spouse’s iPhone 14 used an 18W fast charger. They juiced up the handsets that way nightly for one year.
After that time period, the 5W-charged iPhone 14 showed 98% battery health while the 18W-charged iPhone 14 showed 97%. “Not much different!” Yuryev concluded.
Does using a 5W charger REALLY improve battery health that much compared to a fast charger?
MacRumors Forum user imagineadam tested this!
5W charger on his 14 Pro
18W charger on his wife's 14 Pro
Both charge overnight1 Year later:
5W: 98% Health
18W: 97%Not much different! pic.twitter.com/bavw6o93Vb
— Vadim Yuryev (@VadimYuryev) October 18, 2023
And yet the debate continues
“Yep, this is what I’ve said to most people,” replied user @zollotech. “One to 3% seems to be the difference so it’s not really worth it [to slow charge].”
But there’s always someone citing a different experience.
“I used the Apple charger for about a year and then moved to an Anker 100W charger … in the span of 3 month[s] the battery went from 99% to 91%,” said another commenter. “Then the iPhone 15 was released and it dropped to 87% in 1 week.”
Of course, your mileage may vary depending on various other factors, like how often and how fully you charge your phone.
To check your iPhone battery’s health, go to Settings > Battery, then tap Battery Health & Charging. iPhone displays information about your battery’s capacity relative to when it was new, peak performance and whether your battery needs to be serviced. Apple recommends a replacement battery when it falls to 80% capacity or lower.
