Charges your house battery from the vehicle’s alternator while the engine runs, at the correct profile for lithium — without overloading the alternator.
A lithium house bank can pull more current than an alternator can safely give. A DC-DC charger meters that flow — charging the house bank correctly while protecting the alternator.
It connects the starter battery (alternator) side to the house bank, charging the house bank at the correct lithium profile while the engine runs.
Design your van, boat, cabin or RV system in Wattonomy and it adds and sizes a DC-DC charger when you enable alternator charging, protecting the alternator and feeding the charge busbar — from the appliances you actually run, sized to the recognized standard for your region. You see it on the wiring diagram, in the sized parts list, and in a plain-English build pack that explains the reasoning behind every choice. No account, no email — about a minute to a complete, validated design.
If you charge from a vehicle alternator, almost always yes. It delivers the correct lithium charge profile and stops the bank from overloading the alternator.
Big enough to use the spare alternator capacity without overheating it — commonly 20-50A. Wattonomy sizes it to your alternator and bank.
It takes about a minute. No account, no email.