How to Make a 12v Battery Charger

 

Step 1

• Dc to Dc Step Down Converter
• Alligator Clip
• Multi-meter
• Laptop charger

Dc to Dc Step Down Converter

• it's will convert 19 volt from your charger to 14 volt to charge the battery
• it'll provide constant voltage and constant current . ( very necessary )
• it comes with 3 indicator led (red,blue and green) red show constant current blue show load and green show constant voltage "full charge"

Features

• Input voltage range:6-38 VDC (Note : input voltage not exceeding 38V)
• Output voltage range:1.25-36VDC adjustable
• Output current: 0-5A
• Output power: 75W
• High efficiency up to 96%
• Built in thermal shutdown function
• Built in current limit function
• Built in output short protection function

Step 2

Follow the Steps

1. Cut down the jack of the adapter
2. Remove the outer shield with a blade (Carefully)
3. you'll see 2 wire red and black , black is negative and red is positive (see the image)

Step 3

You can see the label over the board

• The red wire of adapter will go to "IN+" positive of the board (see the image)
• The black wire of adapter will go to "IN-" negative of the board
• tight the screw terminal with a screw driver

Now connect alligator clip

• Red alligator clip wire will go to "OUT+" Positive of the Board (see the image)
• Black alligator clip wire will go to "OUT-" Negative of the Board 

Step 4

Now you need a multi-meter to set it up

• Plug the power to the adapter
• Connect the black alligator clip to negative lead of multi-meter and red alligator clip to positive lead
• you can see 2 Potentiometer over the board (see the image)
• first one is voltage and second one is current
• Now select the DC voltage reading on your multi-meter and turn the Potentiometer with a screw driver until you get 14 volts reading on multi-meter
• Now select the Current Reading on your multi-meter and turn the second Potentiometer with a screw driver until you get 2 amps reading on multi-meter (you can go up to 5 amps all it depend upon the battery capacity if you have a bigger battery "like a car battery you can go up to 5 amps "

Step 5

Just plug the red alligator clip to positive of the battery and black alligator clip to negative of the battery
and plug the power to the adapter
You'll see blue led will glow there it means it is charging If you see green led glows after some time it means the battery is fully charged
If You see Red led with Blue led that means it is in constant current charging