Victron - Isolation Transformer 3600W 115/230V [ITR040362041] Solar panels and cables Or the charger 1+1 model

Or the charger 1+1 model provides 3A to the starter-battery

provided the cells are not permanently sulphated or otherwise damaged

The smallBMS has two outputs

RS485 to USB interface

Battery Combiner and Battery Protector in a robust and compact solution and lets you safely connect any size 12V alternator (and starter battery)

Victron - Isolation Transformer 3600W 115/230V [ITR040362041] Solar panels and cables Or the charger 1+1 modelIndispensable in professional marine energy systems. It prevents electrolytic corrosion and above all serves as a device to guarantee a safe electric system. Toroidal wound technology for quietness and high efficiency. Soft start circuitry will ensure that the shore circuit breaker will not trip when plugged in.