Question Positive/Negative battery wire gauge

[CB56]

Hello all, does anyone know the positive/negative wire gauge size that attaches to the house battery on a 2017 Roadtrek Simplicity. I am considering upgrading to a lithium battery and the post orientation on a group 31 is opposite from my AGM. As a result I have to build an extension for each cable.
Has anyone used the Microgreen inverter(original to the van) set to the #3 AGM2(14.6V charge) ? I have been talking with Li time battery Co. about using their 165Ah Lithium. They said that this setting best aligns with the recommended charging range. I am in the research phase and looking for any information anyone can offer.
Thanks, CB56

 

[redbaron]

The math for wire sizing is standardized. To determine the proper gauge, you need to know the length between inverter and battery and the max continuous amp.

I just did this on my Newmar replacing the Agm with Lithium and discovered that the factory provided wires where not sufficiently sized.