The options for powering devices in a car include using an existing cigarette lighter outlet (also known as a 12V accessory outlet) or installing a power inverter. The primary methods of using 12-volt car power to run your electronic devices on the road include 2V adapter and hard-wired plugs, universal 12V USB adapters, and car power inverters. Today i'm going to show you How to Make 12v Battery Charge. With this charge you can charge any type of 12 v battery even your car battery. it is very necessary in cold days because battery drains out very quickly . This Charger features 2 step Charging 1. Constant Current 2. Constant Voltage . it is very safe and stable for daily use "it's So, how to charge 12v battery with 12v adapter? To charge a 12v battery with a 12v adapter, you will need to connect the adapter to the battery terminals. Make sure that the adapter is rated for the voltage of the battery, and that the battery is rated for the current output of the adapter. 2El4p.