I tested Qi2 charging with and without a case, and the difference surprised me

Wireless charging is a trade-off that places convenience over speed. You can drop your phone on a wireless charging pad at your desk, on your nightstand, or in your car — but it won't be as quick as a cable. Smartphones have copper coils inside that collect energy transferred by the copper coils in a wireless charger, and some of that energy is lost as heat in the process. It's why wireless charging is inefficient compared to wired charging, even if your phone and wireless charger support modern standards like Qi2.2 25W.

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