Sailboat setup with 400 watts solar thru Smart 100/30 MPPT to 400ah LIFEPO4 bank. Alternator to AGM Starter Battery to 30AMP Smart Battery to Battery charger to house bank. Monitored with BMV-700 (house side only).
Would like to add another 200 watts of solar so will need to add a second MPPT. However, I would also like to direct excess solar power to the AGM Starter battery to keep it in good condition and topped up with the correct parameters. What is the best approach to keeping it simple and utilize my existing gear?
Should I direct the new MPPT/solar to the Starter Battery with the AGM parameters and let the existing Bat-to-Bat charger push excess to the House bank (while keeping existing 400 watt solar going to house only)? Been a while since I installed the Bat-to-Bat charger but I assume I could use voltage settings on the Starter battery versus ignition switching to direct when to charge the house bank. This sound like the best approach?