Recently I was scouting the market for a smartphone with reasonable specs and wireless charging. Surprisingly it turned out to be mission impossible. Luckily I was offered an almost-new OnePlus One which despite of its age is still on par with reasonable new smartphones.
The OnePlus One has everything I was looking for except wireless charging (and maybe a fingerprint scanner but that was last on my list). So I decided to hack one in and more or less surprisingly it works. This has been done before (For example on xda-developers forum) but most of the hacks I found are just messy or break NFC functionality.
I got a USB wireless charging receiver with the phone which worked fine so I just cut off the USB cable and replaced it with thin breadboard jumper cables and soldered it to two utmost pins of the phones USB connector. In case you are wondering, the two utmost pins are shorted together, probably to make sure the traces going in the phone can handle the charging current. You would probably be fine with just one as the qi pads can only take 1A and the supplied charger is rated 2.1A but it’s easier to solder to two pins anyway so do it.
At this point charging was working just fine but the bottom part with speakers would never fit because of the additional wires. I sorted that out by carving the plastic to make some room. It turned out that the plastic is very easy to work with so no issues there. Unfortunately the wires need to be crossed as the receiver thing has contacts on the opposite sides than the phone and has shielding allowing it to work only on one side. I was too lazy to start moving the shielding so I just crossed the wires and carved out some more plastic.
The last issue that needs sorting is the shielding behind the NFC antenna that will block the charging receiver. It is likely unnecessary for the functionality of NFC but I decided to rip the damn thing off the NFC antenna and stick it to the battery behind qi coil. That is probably wise to minimize heating of the battery by induction that misses the coil and its tiny shield. This was also the most tricky part as the shield and antenna are glued together but I managed to do it without breaking anything by peeling carefully.
And that’s it, wireless charging working at the speed of 1A charger and NFC still working fine.