How Wireless Charging Works and Why It's Terrible

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Published 2024-04-18
You’ve seen wireless chargers, the tech is now as common as the smartphones they power. But did you know that they come with a big catch? Today we go over the tech behind wireless charging and just how much it actually takes to get your battery full again.

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www.ifixit.com/News/94409/wireless-charging-tradin…

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Big thanks to Creative Electron for the x-rays they sent us!
creativeelectron.com/


Chapters
00:00 Intro
00:18 What to know about wireless chargers
00:36 How does wired charging work
01:11 How does wireless charging work
01:47 Wireless charging issues and some solutions
02:49 Worst Case Scenario of Wireless Charging
03:13 A look at the Tesla wireless charging platform
03:55 Final thoughts


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All Comments (21)
  • @YEdwardP
    What I find most frustrating is that if you're going to go as far as using magnets to ensure "perfect" alignment for the coils, you might as well use them to align metal contacts. Same convenience as "wireless" charging, but with the efficiency of wired charging.
  • It’s terrible until the charging port doesn’t charge and the phone is able to stay alive for another year thanks to it.
  • @Poorgeniu5
    My dad always complains about his phone getting hot when wireless charging in his car and no matter how centered I align his phone, it'll always gets hot and his phone will stop charging to control the thermals. But this video and illustration of Tesla solution of slapping so many coils might be the problem but my dad resorted to wired charging in his car anyway.
  • @MichaelLargent
    I didn't realize the power loss or temps were so high. I'm going back to the ol' wire. Much appreciate the video.
  • @jarboer
    This is exactly why Apple never released AirPower, even Apple realized so many coils in a wireless charger is too much heat to manage properly. Honestly it’s good they pivoted to MagSafe and the Qi 2 standard adopted the same tech.
  • @NotCaptainToad
    Glad to see this video. I worked in a phone store, where I would continuously correct everyone I worked with including my manager, that no, wireless chargers were not in fact better for your battery longevity and to stop telling that to the customers that weren't knowledgeable enough to know otherwise, so they had to trust our experience and advice. I quickly realized that they either didn't choose to believe me or do any research themselves before making recommendations, or didn't care because selling an additional $40-$70 charger as essential for phone health was part of their commissions. I remember them saying they "trickle charge" like it was some feature of the wireless chargers when it's just something most modern phones do. Mind you I still sold a decent amount of them being completely honest with people, as there are still use cases even without a claim of better battery longevity. Convenience, an alternative if your port fails, to name a few. This is one of the many reasons I chose to move into the electronic repair business instead, a lot more honesty there compared to retail phone sales.
  • Living in a subtropical country, 30°C temperature feels almost like late fall or early spring. It's usually 40-42°C during summer and 35-38°C most of the year. So our phone batteries are constantly getting degraded even without charging.
  • @coder543
    At 2:43, the wired connection is represented by a dashed line, the wireless connection is represented by a solid line... an interesting subversion of expectations.
  • @cookiesaregreat
    Appreciate you for sharing your conclusions at the start of the video, and making the video only as long as it needed to be to illustrate your conclusions (unlike most youtubers who intentionally breadcrumb the conclusions to force you to watch through their drawn out videos). Liked and subscribed!
  • @RainbowGin
    I work in a phone store and always recommend wires over wireless charging. It's so much better
  • @cywestbrook7448
    Most phones have a feature to disable fast wireless charging which significantly decreases heat and also slows down battery charging overnight to about 3 hours which can actually help reduce wear
  • @almfreak
    Great video! Thank you for sharing good info with tests and data to back it up! I appreciate the effort that you guys put into teaching things that benefit us users! Keep up the good fight!
  • @quinton1661
    I use wireless charging out of convenience since I'll need to plug and unplug frequently. I always place it under a small desk fan pointed at the phone. It keeps it nice and cool even after charging for over an hour - I imagine the battery temperature is kept a bit cooler from this. For overnight charging it's a 5 W charger to minimize heat. No need to charge from 20% to 80% in 30 minutes when it's going to be plugged in for 7 more hours anyway.
  • @Chuzz1
    commenting to support these findings and data. love your work.
  • @TechInspected
    Appreciate the testing. I was hoping there was more tests about how much batteries degrade with higher temperatures, but that would take a huge amount of work and data.
  • @bjornroesbeke
    It's all about compromises. The ease of being able to pick up the device and put it back to charge in a second is handy for example when you're doing many short trips in a car, and would rather not break the charge port. There's no point in choosing wireless over wired when the device is charging overnight.
  • @TReKiE
    I like to use USB-C magnetic adapters as an alternative. You get the benefits of not having to be accurate with plugging in (plus you don't wear out the USB port), but retain the benefits of wired charging. Such functionality should really be added to the USB spec.
  • @viStringTheory
    I'm glad to see someone calling this out. I wish this were more widely known so people could make informed choices to not purchase or use wireless charging.
  • @judgemint5374
    Finally someone competent pointing out this waste. Thank you!!