Excerpt from: “Guide to Wireless Charging”
Wireless Charging with Cases
Sometimes wireless does not work through your case. This all depends on how strong the wireless charger pad and receiver are. According to a Cnet’s test (“iPhone 8 and iPhone 8 Plus cases: What you need to know”), they recommend that the case be thinner than 3mm to work with the iPhone 8 and 10’s built-in wireless charging.
If you want to get a hefty phone case and still have wireless charging then you need to invest in a wireless charging case. Case makers like Morphie sell cases like the Charge Force which uses the Qi standard for wireless charging and it’s magnetic so it says still on magnetic wireless charging pads. They also make a wireless charging case called the Charge Force Juice Pack Air which has an internal battery and like the case.