What is a DC-DC Charger?
A DC-DC charger (also known as a battery to battery charger) converts the output from your primary battery and charges your secondary battery using optimal charging. It is a smart charger that runs off 12-volts. It takes power from your vehicle’s alternator while you are driving and creates an output voltage and current that will charge and maintain your ever-important second battery. DCDC chargers are primarily used to charge a battery bank made up of one, or more batteries that are designed to be deeply discharged.
Do you need a DC-DC charger?
Whether you need a DC-DC charger depends on your battery system and how you use it. If you have a dual battery system in your vehicle and you want to charge your auxiliary battery while driving, then you will need a DC-DC charger. The reason you need a DC-DC charger is that most of the time your vehicle battery is a lead-acid battery, so your alternator is designed to charge a lead-acid battery.