?Compatible Multiple Battery Types? Compatible with a multitude of alternator types, the ACOPOWER 12V DC to DC charger offers correct charging multiple 12V batteries: LiFePO4,AGM, Flooded, Gel, and Lithium batteries.Knob operation makes it convenient to quickly select the type of battery that needs to be charged. ?Smart Multi-Stage Charging? The 40A DC to DC smart charger will charge your house batteries from the starter battery by 3-stage charging (Bulk, Boost, and Float), to make sure it optimally and automatically charges to 100%. ?Various Protections For Ultra Safety? The ACOPOWER on-board battery charger with high-quality offers Over-voltage Protection, Over-temperature Protection, and Reverse Polarity Protection to ensure the operation safety. It also isolates the input and output to prevent voltage transmission errors and interfere with house battery charging. ?Protect Your Starter Battery?The DC-DC battery charger is capable of identifying whether the generator is started, to prevent over-discharge of the starting battery and protect the generator. ?Reliable Quality & Easy Installation?The compact and robust design of the dc to dc charger makes it suitable for all conditions, and also resolves your concern about the limited room in your vehicle. Product Description 12V DC TO DC BATTERY CHARGER Battery Voltage: 12V Charging Current: 40A Input Baftery Voltage Range: 8V-16V Charging Voltage Range: Lead Acid: 13.5V-14.8V Lithium: 14.6V