I have a Balmar 175A alternator with an external programable regulator, alternator temp protector, battery temp protector and alternator protection module used to charge my 400Ah lithium house bank. With this configuration and protections, is there any reason I can't charge the start batter running a smart charger from the lithium (input) to the start battery (output)?
You should be able to run an Orion DC to DC charger for this service. If the starter and house bank negatives are connected you can use the non isolated version otherwise if the negatives are not connected then use the isolated version. Do you have loads other than starting on the starter battery. You could set the Orion up in power pack mode at the starter battery float voltage as it will be kept permanently at this voltage rather than setting it up as a 3 stage charger.
Beware some of the non Victron starter battery trickle chargers, they do not boost the voltage so are not suitable for charging lead acid batteries from lithium batteries.
so, long story short:
is possible to charge the start battery using a dc-dc charger and getting energy from the bank battery, just connecting the + from the battery bank at "in" and the + to the start battery to "out".
(of course respecting voltage, amps)
correct?
