Integrating The Qi Wireless Charger
With the panel in question removed, getting the charger into place shouldn't be difficult. I used a standard micro-USB cable and wall plug to verify that the charger still worked through the panel. You'll want to double-check this yourself; as a standard, Qi facilitates charging between planar coils millimeters away from each other, so distance does matter. For my application, I manually held the inductor coil up against the panel's surface with the phone in place. Pleasantly, the phone charges in the spot I planned to keep it.
Once you know where charging works best, whip out your hot glue gun and secure the hardware. I applied hot glue around the metal plate to keep it in place; the PCB received two dabs as well. A bit more was applied to the wires leading to the micro-USB port as well, ensuring it wouldn't move much.
Adata uses a charging status indicator on the CE700. When a device is receiving power, the light flashes a green LED. It's off when there's nothing on the charging pad. I wanted to make this indicator visible, so I drilled a hole that'd fit the LED, routed the wire to the top of my phone pocket, and applied some hot glue to keep it in place. Now, with the phone in the pocket, the LED confirms charging (even though the Nexus 5 has a charging indicator as well).
After gluing everything into place and checking once more that it all worked, I let the phone charge for an hour to test for overheating issues. Fortunately, the charger remained cool the whole time. I was clear to wire everything into the car.
Hardwiring the charger requires access to the accessory outlet. Whether or not the outlet has power when the vehicle isn't running depends on the platform. As a safety precaution, though, always disconnect the car's negative battery terminal before messing with any of the wiring. The Mazda5's accessory outlet only has power when the van is in accessory or running mode. I actually prefer this over outlets that provide constant power. You're less likely to accidentally drain the battery.
Wiring the EDO Tech micro-USB adapter is particularly easy, since there are only two wires. Wire taps are perfectly adequate for such a low-draw application, so that's what I used. The black wire is almost always ground, but I'd suggest looking up the color codes for your specific vehicle just to be sure. Alternatively, you can always use a multimeter or test light before disconnecting the battery to identify the hot wire.
With the adapter connected, reconnect the battery and test the charger to make sure it works. Then, shut the car off to cut power and start cleaning up. As with building a PC, wire management is an important step. I used zip ties and electrical tape to secure the EDO Tech micro-USB adapter's wiring. Extra tape went into minimizing the potential for squeaks and rattles.
Finally, reinstall the panels you removed and marvel at your new integrated wireless charger.
