7.5W standard offers negligible improvements in Qi wireless charging speed

Just how fast is faster 7.5W wireless charging in iOS 11.2? As per early testing conducted by Matt Birchler, the difference between 5W and 7.5W charging speed is negligible.

Before iOS 11.2, wireless charging on iPhone 8, iPhone 8 Plus and iPhone X was limited to 5W. iOS 11.2, which is currently in beta, raises that limit to 7.5W—a 50% increase in power on paper.

Having tested the speed difference between 5W and 7.5W implementations, Birchler initially saw no change in performance as his phone took 30 minutes to reach 11% charge.

At the end of Birchler’s two-hour test, his iPhone 8 Plus running iOS 11.2 went from zero to 47% versus 40% with this same charger before iOS 11.2.

He summed it up:

If you have 2 hours to change your phone and there is a 7% difference in the change level, I don’t think that’s a huge deal. Especially when you compare 30 minutes on the charger, I saw literally no change in performance, as it took 30 minutes for the phone to reach 11% charge.

To put his findings in context, the standard 5W charger that came in your iPhone box gets your iPhone 8 Plus to 79% in 2 hours (68% faster) and up to 21% at the 30 minute mark (91% faster). And if you go the fast charge route, Apple’s 29W USB-C charger gets your iPhone 8 Plus to 100% in 2 hours (112% faster) and up to 43% at the 30 minute mark (391% faster).

Another way to look at it: 15 minutes on a wireless charging pad will get you to 6% and the fast charger will get you to 23%. Bottom line: while 7.5W is an improvement, it’s still lacking in the world of wireless charging.

Keep in mind that the current Qi 1.2 standard allows for up to 15 watts of power for wireless charging. There’s no indication as of yet whether Apple will be supporting 15W wireless charging on the current iPhone 8 and iPhone X series.

Subscribe to iDownloadBlog on YouTube

Aside from Belkin and Mophie, which partnered with Apple on wireless charging, 7.5W wireless charging is supported by other wireless charging mats, like the RAVPower charger.

If you want to charge your iPhone faster than wireless charging, you’re advised to use your 12W iPad wall adapter or a USB-C Lighting cable and a USB-C fast charge wall adapter.

iOS 11.2 is currently in beta, and will release to all users in the coming weeks.