How to Charge 12V Battery With 5V Mobile Charger

Introduction: How to Charge 12V Battery With 5V Mobile Charger

About: Its all about life hacks, tools, scientific & creativity instructables ~ electron7m

Hi !

In this instructable, you will learn to charge a 12v battery with a 5v mobile charger at home with a simple dc to dc boost converter for voltage step - up.


Step 1: DC to DC Converter :

The video link for the making of a simple dc to dc converter has been provided below.

Its function is to step up the input applied voltage by 3 to 4 times which can be adjusted by by choosing different values of inductors.

Transistors used for the circuit are 13009 npn.


Step 2: 12v Battery :

The 2nd step is a discharged 12v battery.

Here as you can see in the picture that the battery is at 8.46 v where it should be at at-lest 11 volts which means that its really discharged.

Its actually from an old laptop.


Step 3: Connection & Testing :

Connections are simple.

1- Connect the +ve of the rectifier to the +ve of battery & -ve to the -ve.

2- Connect the A.C input of the rectifier to the output wires from the dc to dc converter.

3- Connect the input wires of the converter to the mobile charger (+ve to +ve & -ve to -ve)

4- Simply turn on the charger switch and it should start charging.

Thankyou !!!!

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    3 years ago on Step 1

    The 12V battery as shown seems to be made up of LIPO cells (3 pairs in series). LIPO cells need to be charged carefully with circuitry that is LIPO aware and ensures there is no risk of overcharging.


    Reply 3 years ago

    Well auto cut and all could be added in the circuit but this is a general video.A simple way.