We all use mobile phones and definitely, a discharged battery makes the phone useless. A wireless recharging battery case can be a solution. You just have to make sure that it is gently placed near the battery and the power transmitter, How can we do this? The following tutorial of the Adafruit has the answer.
Have a closer look, firstly just to protect the battery case from getting damaged. Make sure that the Qi charging stickers must be used that terminate in Micro/Mini USB connectors. Be careful while modifying high capacity batteries.
Now closely examine the exterior of your battery case and remove stickers or plugs, if any. You will find some hidden screws to open the cover. It could be glued or welded too but nothing to worry once the case is fixed it can again be welded or glued.
After the cover is removed, just select the PCB from the options available, which fits best with your battery case. You will notice a small tiny riser connector flipped at 180 degrees, this is the place from where battery case passes power through to the phone.
There are some OTG (on the go) connections too in other phones. This phone battery does not support OTG but others might do so.
On examining the circuit, there are two pins VCC (outer right pin) and Ground (outer left pin) via the micro USB connector on the charging controller below.T2 point might be connected to VCC.
Now if we have rightly placed the charging receiver, it is the time for checking the results-Use a multimeter and identify the Ground and VCC pins. You might use a painters tape for taping the charging receiver to the transmitter as shown, and use the weight of the transmitter to hold the receiver down.
A Wireless Case for Recharging Battery (Image Courtesy: Adafruit)
Now, plug in the USB cable and test traces near the connector for +5 volts. Once the receiver is all set and getting a proper voltage cut a short length of red and black hookup wire. Connect the VCC and Ground from the charging receiver to the micro USB pins.
Cover all the exposed traces with the insulative tape that can beer high heat, Kapton works well.
Ensure that wires do not mess with each other and do not interfere with any port, button or plugs. Now, reassemble your case place the power transmitter on top, green light means go.
It is advisable to monitor first few charge cycles closely just to avoid complications if any.