I want to install a voltage sensitive relay between my vehicle starter battery and 12v leisure batteries. Battery are 100ah each lithium lifepo4 (i read somewhere that this makes a big difference to which relay you can use)

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My van is a 2018 ram promaster with a 180amp alternator. similar to mercedes spinter vans.

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I was hoping to get the widely available and reliable 140amp voltage sensitive relays that charge the leisure batteries only when the alternator is on and charging the starter battery. But now i am worried that my alternator is too strong and will damage the device or my battery bank system. It's incredibly difficult to google for this situation. And if i do set this up what wire size would i need for this? 1/0? the distance will be about 20-30 feet.

I really need help here.