I bought one of those cheap chinese Qi chargers. It’s only $6.28, including shipping. It charges my Nexus 4 flawlessly and is definitively worth the money.
The specifications say it draws up to 1500mA at 5V (USB). You can get the actual charging current via adb, depending on your device:
adb shell "cat /sys/class/power_supply/battery/current_now"
mine is charging at around 500mA.
Here you can see which screws you need to unlock to open the charger
I’ve switched out the the LED to a red one as the blue LED was disturbing me at night.