Quote from: Daviy on March 31, 2019, 19:05:47
They would rather fail than be slightly thicker? That's mind boggling.
For wireless charging to work, the coils in the charger and device have to be in close proximity. To do three layers of coils, you would have to ensure that the bottom coils are close enough to the surface of the charger to engage the device placed on it. So, that distance is the main factor in determining the thickness of the charger. Add a few millimeters and you might as well not have the bottom coils. Put a thick case on your iPhone and it might not work at all. While I agree that Apple is often too obsessed with thin devices, that's not the problem in this instance.
Whenever the bottom coils are in use, heat is going to rise to the coils above. If the middle and top coils are also operating, a ton of heat will rise to the devices that are sitting on top of the pad. That's bad for your phone and its battery.
The best solution would be a more efficient charging coil that wastes less electricity (which is where the heat comes from), but that's easier said than done. I wonder if Apple was trying to do just that, but can't crack it.
For now, I'm of the opinion that wireless charging is best in cases where it's difficult to add a charging port to a device, such as in waterproof toothbrushes and smartwatches.