How to Make an Automatic 12V Battery Charger

Hey! everyone My name is Steve.

Today I'm going to show you How to Make a 12v Battery Charger

Click Here to See The Video

Let's Start

Features

Input Power

110-220 v AC

Output Power

1.25-24 v DC Adjustable at 8 Amps

Built-in Protection

Short Circuit Protection
Over Load Protection
Over Charge Protection

Charger Features

Constant Current Charging
Constant Voltage Charging
Full charge indicator
Charging Indicator

Continuously asked Questions

Q - Can I leave it overnight

A - Yes! For Sure this will not overcharge your battery just because we're using constant voltage there will be no potential difference to make your battery overcharge

Q - Why you are setting the voltage to 13.8v

A - Just because when a 12v battery get fully charged the voltage is 13.8v Google it for more information

Gallery

Things You Need

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Banggood

24v SMPS - https://goo.gl/4hb3Sj
Dc to Dc Step Down - https://goo.gl/EM8LF7
Volt Meter - https://goo.gl/EM8LF7
Acrylic Sheet - https://goo.gl/EM8LF7
PCB Stand-Off - https://goo.gl/EM8LF7
Heat Shrink Tube - https://goo.gl/EM8LF7
XT60 Connector - https://goo.gl/EM8LF7
Alligator Clip - https://goo.gl/EM8LF7
Soldering Iron - https://goo.gl/EM8LF7
Rubber Bumpers Pad - https://goo.gl/EM8LF7

Aliexpress

24v SMPS - https://goo.gl/pFbm59
Dc to Dc Step Down - https://goo.gl/atZGVC
Volt Meter - https://goo.gl/atZGVC
Acrylic Sheet - https://goo.gl/atZGVC
PCB Stand-Off - https://goo.gl/atZGVC
Heat Shrink Tube - https://goo.gl/atZGVC
XT60 Connector - https://goo.gl/atZGVC
Alligator Clip - https://goo.gl/atZGVC
Soldering Iron - https://goo.gl/atZGVC

Amazon

24v SMPS - http://amzn.to/2wSnT0Y
Dc to Dc Step Down - http://amzn.to/2yCfbWQ
Volt Meter - http://amzn.to/2yCfbWQ
Acrylic Sheet - http://amzn.to/2yCfbWQ
PCB Stand-Off - http://amzn.to/2yCfbWQ
Heat Shrink Tube - http://amzn.to/2yCfbWQ
XT60 Connector - http://amzn.to/2yCfbWQ
Alligator Clip - http://amzn.to/2yCfbWQ
Soldering Iron - http://amzn.to/2yCfbWQ

https://www.utsource.net/ is an online platform for electronic technicians, Makers, Enthusiasts, Kids to find electronic components

Stand Off Installation

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First, install the standoff "as shown in the image "
Do the same for SMPS and DC to Dc Convertor

The Acrylic

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First, pull off the protective layer from the acrylic sheet
Now place your components " as shown in the image "

The Drill

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Now use a marker to make the point for drill
Now use a 2mm drill to drill the holes
And now go for 3mm drill bit and at last counter shink all the holes " as shown in the image "

Assembly

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Now use some screw to screw the board with acrylic sheet " as shown in the image "

Wiring Diagram

Wiring Part 1

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Now solder the XT60 with Ammeter with some wire " as shown in the image "
And then use heat shrink tube to secure the connection

Double Sided Tape

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I used some double-sided tape to hold the Ammeter and XT60 Connector

Wiring Part 2

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And I Passed all the wire underneath the board till last and connected it to the converter output " as shown in the image "
And now I took 2 wire along with ammeter wire and connected it to the output of SMPS " as shown in the image "
And now I connected the ammeter wire and passed all the wire underneath the board till last and connected it to the converter Input

Output Wire

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I used XT60 connector with 2 alligator clip and wired it together and used some heat shrink to secure the connection

Input Wire

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I used XT60 connector and connected it to the Green connector for mainline input " as shown in the image "

Final Assembly

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I used couple of screws to close the upper acrylic sheet
And used some rubber feet on the bottom

Looks neat

Calibration

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Now connect the main input wire
In order to set the current, you need to short the output wire and now set the current with the potentiometer " as shown in the image "
now you need to disconnect the output wire in order to set the voltage and now set the voltage with the potentiometer " as shown in the image "

My Settings

Set the Voltage to 13.8v
And set the current to 1 Amps or more it depends on the battery size

Find out the current

Use this formula - Battery Capacity x 1/10 = setting

Example

I used a 7 amp battery, now let's put the formula
7 x 1/10 = 0.7 and here I set it to 1 amp " You can go for little higher current but not too much "

Finishing Up

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Now just plug the battery and it's all set
You can see the ammeter it's drawing about 1A just because we have limited the current it is the safest way to charge the battery
And when the battery will get fully charged " This will automatically stop the charging " Just because we have limited the Voltage and there is no potential difference to overcharge the battery

Indicator

Red Light - Charging
Blue Light - Full Charged

That's all for today guys!

Click Here to See The Video

You Just Made It

Thank you for visiting my Instructables

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