2-Pack Insignia 10W Qi Certified Wireless Charging Pad

In general this is a function of wireless charging. Inductive charging is all about running an alternating current in a copper coil which generates a magnetic field. Then, when another copper coil is properly aligned within the same magnetic field a current is now generated within that coil without any wires running between the two. Magnetism!


Now look no further than your stovetop to find an example of what happens to a copper coil through which you run an alternating current! It also doesn't help that you have to pump about twice the power into the space/air around the device relative to what can be drawn from the second coil (see my note about efficiency above). This is why 9W/10W Qi pads must be equipped with 18W charging adapters.

You may want to experiment with lower power Qi charging (5W), but ultimately if your goal is efficiency (i.e. less waste heat) there is no competing with wired charging. My favorite "terrible" idea product these days are portable battery banks with wireless charging, since for all their convenience you're basically tossing out half your battery capacity as a function of the design. MagSafe, for example, is a great way for Apple to reduce their SKUs for extended power batteries (vs. customized cases for each model), but not necessarily a massive improvement in portable power storage for the end-user.

Good luck!
Jon

Be aware, the 20w charging pad is total charge for 2 pads. 10w each pad max, not 20w charging for just one device.

Assuming you want/need the associated adapters and cables, the prices for the 5W and 10W models are more than competitive with they typical $5-6 unit price for which you can buy commodity 5W Qi chargers (like the IKEA option [ikea.com], which does not include an AC adapter or cable). Of course, not everyone will find the included cable sufficient for their needs.

The 15W charger would seem to be price very competitive with comparable Qi chargers, especially with the inclusion of the power adapter. However, the included power adapter is proprietary (so has no other application for wired charging; contrast that with the decent 18W USB quick charge adapters included with the 10W chargers that have 9V and 12V modes). Also, the Insignia 15W charger doesn't incorporate the fans or large heatsinking associated with other 15W Qi chargers. Some might consider this a benefit, but failing to address heat when 15W charging might have negative implications for your device being charged.


As with all wireless charging, about 50% or worse. MagSafe improves on that slightly thanks to getting the coils aligned as part of the system (i.e. - tightly coupling).

Personally I love using simple 5W chargers as a slow-charge option for my work desk (especially handy when dealing with a mix of device connectors). However, that is indeed a convenience and not optimal for efficiency. For that I use a dedicated 500mA wired charger for overnight charging. For those Samsung OneUI users seeking to extend the life of their battery by protecting the device from overcharging, I'd also recommend their batterv protect setting which limits charging to 85% of capacity.

Good luck!
Jon