The maximum range of the current Qi chargers is only about 7 - 10 mm (and 10 is stretching it). And that includes the thickness of the original phone back, the thickness of the plastic case on the charger, and any air gap between the coils in the phone and charger.
In other words, if the coil is inside the phone, you're not likely to get wireless charging to work through a thick case. There are Qi coils that are designed to stick to the inside of a case, and connect to the phone through the micro-USB port. Those might work, but then you pretty much have to remove the case and connector if you want to connect the phone to a computer.
There is an updated Qi standard now that allows for more power, and therefor greater distance between the two coils. I don't know how soon we'll see devices that meet that standard, though.