HiTech DC-DC Charger, 40A

HiTech DC-DC Charger 40A – Charge Your House Battery While Driving

A DC-DC charger (also called a battery-to-battery charger) allows you to charge your caravan's house battery from your tow vehicle's alternator while you drive — without the risk of the alternator seeing too heavy a load or damaging modern smart alternators.

At 40A, the HiTech DC-DC charger delivers a meaningful charge to your house battery during a typical day's driving, complementing your solar setup and reducing dependence on shore power. It includes a correct charging profile for both lithium and lead-acid batteries.

Key Features

• 40A Output Substantial charge rate — charges a 100Ah lithium from 50% to full in approximately 2.5 hours of driving

• Safe for Smart Alternators Isolates house battery load from vehicle alternator — no risk to modern vehicles

• Lithium & Lead-Acid Compatible Correct charging profiles for both battery types

• Complements Solar Charges from alternator while driving, solar handles camp — best of both

HiTech Quality Built to the same standard as the broader HiTech electrical range

Brand: HiTech

Type: DC-DC charger (battery-to-battery)

Output: 40A

Input: Vehicle 12V / 24V DC

Battery Types: Lithium LiFePO4 and lead-acid (AGM, gel, flooded)

Application: Vehicle alternator to caravan house battery charging

Price: $490

Do I need a DC-DC charger if I already have solar?

Solar only charges your battery when the sun is shining. On overcast days, in winter, or when you're spending multiple days without sun, a DC-DC charger ensures your house battery gets meaningful charge every time you drive. The combination of solar and DC-DC charging is the most robust off-grid setup.

Won't a direct cable from the vehicle battery charge the house battery?

A direct cable (ignition-controlled relay) will transfer voltage from vehicle to house battery but can damage modern Euro 6/Euro 6d smart alternators that reduce output when a load is removed — they don't tolerate a direct battery load well. A DC-DC charger presents a stable, controlled load that's safe for all vehicle types.