3 shell lithium batteries.A boost circuit raise set voltage to 14,8 V for charging the car battery.
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Natteries taken from laptop battery.
All other componets are from scrap electronics.
Step 1: Box.
Two usb chargers for cellphone. The car adaptor forward voltage to battery.
Step 2: Finishing Touch.
switches and paint.
Step 3: Last Minute Idea.
A led light made from scrap.