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I have a Qi charger and it works OK for its purpose. I thought it would be possible to install it under a table without cutting a big hole. However, my testing shows this isn't possible, at least with the model I have. It's an Insignia 15watt model. It's supposed to have 3 coils of 5 watts each. I've found that I can only lift the phone a few millimeters above the induction coils before it stops charging.

All the furniture mounted models I've seen require a huge hole for their induction coil and you set your device on that.

I was thinking of buying the raw coils with power controller, but I don't want to waste too much time with that if it isn't going to work.

Any thoughts?

I have a Qi charger and it works OK for its purpose. I thought it would be possible to install it under a table without cutting a big hole. However, my testing shows this isn't possible, at least with the model I have. It's an Insignia 15watt model. It's supposed to have 3 coils of 5 watts each. I've found that I can only lift the phone a few millimeters above the induction coils before it stops charging. All the furniture mounted models I've seen require a huge hole for their induction coil and you set your device on that. I was thinking of buying the raw coils with power controller, but I don't want to waste too much time with that if it isn't going to work. Any thoughts?

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[–] • 1 pt

I'm guessing that the magnetic field isn't very strong. I'd have to find a circuit with a much stronger field output. I don't want to build something specific for it. Perhaps if I ganged up a few charging circuits and put 12 induction coils, that could do it. Perhaps winding the coils around a ferrite core would strengthen the field. It looks like these chargers don't have a ferrite core.

[–] • 1 pt

No, they're not strong. Wireless charging is already inefficient as all get out, a little space in-between the charge coil and the receiver and it can't transfer enough power to make it worthwhile.

[–] • 2 pts

Just because it cannot be done, doesn't mean we shouldn't do it, right? Maybe a 1KW charging circuit would allow an inch gap. After all, electricity is green. You and your silly efficiency!

[–] • 2 pts

Yeah, those silly physical laws of the universe. Who needs them?

[–] • -1 pt (edited )

Take the door off of a microwave and mount it underneath.

For standard plywood and solid wood - 3/4" thick - Set microwave power to High. 1/2" thick set microwave to Medium To charge from 75% to full will take 2.5 minutes. 50% to full will take 4 minutes.

For particleboard (Ikea wood) Regardless of thickness, set microwave to Low. Charging time of 6 minutes to go from 75% to full. 50% to full takes 10 minutes.

If your phone's battery is less than 50%, do not charge for more than the amounts above, or your phone may overheat. Instead, charge phone, then wait 1 hour, and then top up the charge.