Mike: Recommend you post your question on the forum. I haven't researched anything about updating to lithium batteries and all the additional requirements that drives in terms of updating to a BIM from a BIRD, inverters, converter change due to lithium charging requirements. All this is way outside my area of expertise. But there are quite a few folks that have done this and I'm sure if you ask pn the forum you'll get a good response.

Hi Ed. I just downloaded and printed your EXCELENT manual. I am fitting a 200AH LiFePo battery to my 2015 Axis 24.1 and want to incorporate a Renogy 20A DC to DC charge controller to keep the alternator from frying itself trying to charge a deeply discharged lithium battery. I like the BIRD unit and attendant relays shown in your manual and am reluctant to bypass them entirely. Do you have any suggestions? The Renogy DC2DC controller incorporates an isolation relay of its own to keep from discharging the chassis battery along with the house battery. Any suggestions?