Does the case interfere with wireless charging?

Question

Electronics

Finally began to actively use QI wireless charging. But charging does not always determine whether the phone is on it, sometimes it helps to just pick it up and put it down. I recently bought a case for the phone (dense rubber or some kind of mixture of rubber and plastic).
And I think - this is a dielectric, and a couple of extra millimeters.
How exactly does induction charging work?
If the induction focus is directed to the very bottom of the phone, where the charging receiver should be located, does any case "push back", reducing efficiency?
How does a dielectric affect inductance?
Of course, I googled the principles of work, but I could not find the question about the case.
In principle, it charges this way and that, to conduct accurate measurements of the time and quality of charging with and without a case - many cycles are needed, and I would like to clarify the theory ... in childhood there were triples in physics :(

Answer 1

How does a dielectric affect inductance?

No way. We influence the material, thickness, geometry, and a bunch of other factors. Whether it's a dielectric or not, it doesn't matter. Metal is a conductor, but does not pass EMP well. Read about the Faraday cage.
If you have QI charging, then most likely an Android phone. And Android knows how to build a fairly accurate charging schedule.

Answer 2

There are different wireless chargers , when I chose for myself, in the store only one worked well with a thick case, this is Skyway ( wireless.skyway-tm.ru ). The rest with a case did not charge.

Answer 3

+ I’m not a big connoisseur in this, but I know that the insulation will need to be changed, so I took good tires from these guys https://polyfacture.ru/
they are specialists on tires, so they fitted me one tire for winding
https://polyfacture.ru/