How to make a DIY Power Bank with 9 Volt Battery

Contents hide

In this tutorial, we will show you how to make a simple Power Bank using a 9 Volt battery. We can use this power bank during a power outage to charge our mobile phones. A 9V battery can give enough energy to a mobile phone to make important calls or send messages. The charging voltage for the mobile phone battery is 5V, So we will use a voltage regulator to convert 9V from the battery into 5V.

Hardware Components

The following components are required to make Power Bank Circuit

S. NO	Component	Value	Qty
1.	Micro USB Cable	–	1
2.	IC	LM7805	1
3.	Battery	9v	1
4.	Card piece	–	1

LM7805 Pinout

For a detailed description of pinout, dimension features, and specifications download the datasheet of LM7805

Connections

Connect the Black wires of the battery clip and USB cable together.
Connect the Red wire of the battery clip to the Input (Pin 1) of the Voltage regulator.
Connect the Black wires to the Ground (Pin 2) of the voltage regulator.
Connect the Red wire of the USB cable to the Output (Pin 3) of the voltage regulator.
Cut a small piece of card paper and attach the voltage regulator and battery clip to it.
Now, you can test the circuit by connecting your Mobile phone to the USB cable.

Working Explanation

A normal 9V battery has a rating of 500 milli-Ampere Hours (mAh), so you will need approximately 4 batteries of the same capacity to fully charge an iPhone 8. The voltage regulator used in this circuit is LM7805. Given below is the Pinout diagram of LM7805:

We will connect the positive wire of the battery clip to the Input pin. Similarly, we will connect the positive wire of the USB cable to the Output pin of the regulator. The ground of both wires will be joined together and they will be connected to the ground pin of the regulator. Overall, it will convert 9 volts supplied from the battery into 5 volts, which is the required voltage for charging a mobile phone.