LAS VEGAS -- It seems like I've been hearing about true wireless, over-the-air charging for three years without anything real to show for it. But now there's hope here at CES 2019.

A new smartphone case promises to keep your phone topped off forever without ever having to touch an outlet. Meet the aptly named Cota Forever Sleeve.

The result of a partnership between Ossia and Spigen, the Forever Sleeve gets its juice from a transmitter, which could be installed as a tile in the ceiling or could be something that just sits in the corner of your home.

The demo sleeve I saw here at CES 2019 encased an iPhone XS and used the 2.4-GHz frequency, but the final product will use 5.8-GHz. The 3D printed case was bulky and on the heavy side, but Ossia and Spigen say the final product should be sleeker.

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The proof-of-concept Forever Sleeve contains a lithium-ion battery that receives power wirelessly and then supplies power to the iPhone’s battery. The goal? Keep your phone topped off and ready to go when the user is away from the wireless power transmitter.

At a distance of 2 meters, Ossia says that you'll get about 3 to 4 watts of power, which means it would take 6 to 7 hours to charge a dead phone with a big 4,000-mAh battery.

But that's beside the point. The idea is to have continuous wireless power so that when you're home or near a transmitter, you should never really have to worry about recharging a phone.

Now here's the bad news. Ossia says it plans to work with Spigen to deliver a Cota-enabled phone case for 5.8GHz "by or before 2020."

I guess I can wait one more year for the future.

Photo Credits: Tom's Guide