Here is a simple trick to mak works your mobile battery .For this you have to make simple 12 V power circuit which gives your sleeping or uncharged mobile batteries a 12 voltage shock to charge your battery.
Step 1: Follow the steps:
1. Remove battery from mobile.
2. Clean the surface of contact of batteries.
3. Connect the output of circuit to your mobile battery (as shown in picture) only for 20-30 sec not more than that.
4. Connect positive terminal of circuit to positive terminal of battery & negative terminal of circuit to negative terminal of battery.
5. Then connect your battery to again to your mobile, your mobile will start. Still it shows warning that “low battery”.
6. Now you can connect your normal battery charger to mobile for charging.
7. Your mobile battery is now working.
This trick can be used for following condition of batteries:
1. If your battery should be in good condition.
2. If battery should not be wearied out.
Step 2: To make this circuit you required following things:
• Four 1N4001 diodes
• LM7812 regulator
• 230-15v step down Transformer
• 2200uF capacitor
• 0.1uF capacitor
• Jumper wires (I used some plain wire as jumper wires)
• Heatsink (optional)
Make the circuit as shown in picture.
(Note: Note that connect the circuit to battery only for 20-30 sec )
Feel free to ask me any questions. I will help you!