Charge your batteries while you drive using your vehicle's alternator or via solar, using the inbuilt MPPT solar regulator with this 40A Under Bonnet DC-DC Charger from HardKorr. Coming with a dedicated charging setting to suit 12V SLA, AGM, gel, calcium, and LiFePO4 systems, it's ideal for most 4×4, caravan, and camper trailer dual battery setups. Built with a high heat tolerance, the charger can withstand temperatures up to 80°C, making it ideal for mounting in places like your engine bay or 4×4 canopy.

The DC-DC works by converting the power from your alternator into a charge voltage that carefully, but quickly, suits the status, and chemistry of your auxiliary battery all without affecting your vehicle's starter battery. Designed to work on most vehicles, it's compatible with either traditional or fixed/smart alternators and will feed up to 40A into your batteries per hour.

There's a dedicated Anderson-style plug coming from the unit for the inbuilt Maximum Power Point Tracking (MPPT) solar regulator function. The charger will use the power coming from the solar input when it detects it as either the only available power source, or if the solar input exceeds the power being produced by the vehicle. Able to regulate up to 40A, it's able to handle solar up to 15% more efficiently than traditional Pulse Width Modulation (PWM) regulators.

With a high heat tolerance, the charger can be mounted in most places including under the bonnet. This is particularly useful in vehicles that have the space for an additional battery in the engine bay, like in Land Cruisers and Patrols, helping to not only reduce voltage drop but also free up some space in the back of the vehicle.

The charger comes with three pre-wired Anderson-style plugs to make installation simple. The black plug connects directly to the auxiliary battery, the traditional grey plug is the dedicated solar input, whilst the three-pin Anderson-style plug can be used to quickly connect to the vehicle.

Note: Aside from the accessories mentioned, items pictured in the last image are for illustration purposes only.