Lithium Batteries and Alternator Protection

[Auztone]

Hello All,
I've search the site and can't quite find the information I'm looking for. I'm considering installing Lithium Batteries in my 2019 Fleetwood Southwind 36P. My inverter/charger can support Lithium and the install looks pretty straight forward other than one issue that I'm looking from others that have installed Lithium batteries and needed to install a DC to DC charger to protect the alternator.

The problem I have is that the feed from my main battery and alternator feed into my BCC. It would seem simple just to install the DC/DC charger before the feed into the BCC but at the point of install to the BCC is also the connection for the chassis wiper power and Main AGC fuse (attached PDF on page 1). My assumption is that I could be limiting the wiper and main AGC fuse and be causing other problems.

What have others done in regards to the BCC and still keeping some functionality? Any help is appreciated.

Thanks!

[computerguy]

Needed to look a little harder. Here is my very detailed post on the install in a Bounder
Bounder Lithium Solar Install

[Auztone]

Good information but not what I'm looking for. You simply installed a manual bypass to protect your alternator from running all the time or when your batteries are fully charged. I would like to install a DC/DC charger or something else and keep as much of the original function of the BCC if possible. I don't plan on installing solar at this time so one of my main ways to charge the batteries is via the alternator when actually traveling between sites. I would like something that would limit the current draw and also protect the alternator without any manual switching but more automatic that works via the ignition switch and no possible human error.

[twinboat]

You can remove or disable the isolation solenoid and install a lithium BIM 225. Use heavy cables from both large terminal to the BIM.

Otherwise, disable the isolation solenoid and just connect the B to B charger to each side of it. No need to find the alternator output wiring. You want that to contionusly charge the chassis battery.

Doing it this way makes converting it back if you trade it in and keep the batteries.

[jcussen]

I used one of these, and retained the normal boost relay to connect both banks if necessary. https://www.solar-electric.com/victr...LECwLBFJK4ZT5u

[twinboat]

I marked the only 2 points where the batteries connect during charging.

Take a small wire off that solenoid and its disabled.

[Auztone]

I've seen these. Let me try and find an actual P/N on my BCC and get a wiring diagram. I'll see if this is an option and if it will possibly fit.

[Auztone]

So I have the RV Customs Products F73-1020 BCC and was able to download the block diagram from the website. Looks pretty straight forward and should be able to identify the signals at the plugs and the wire color. Looks like now I should start my wiring diagram for the overall project and my parts list. I believe I have the information I'm looking for now and my goal of keeping it as much "normal" as possible. Thanks for the information.