Installing An RV Lithium BIM Precision Circuits LI-BIM 225 – Battery Isolation Manager – RV Upgrade

As part of my affordable RV Lithium Battery (LiFePO4) upgrade I replace and install a new Lithium compatible battery isolation manager (BIM) from Precision Circuits called the LI-BIM 225. This is the fifth video of five. Links below.

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[johndodi]

Thanks Lou, I really appreciate it because I have the same setup in my Forester. I’m getting to change out my old lead acid batteries to Lithium-ion batteries.

[steveborgman]

That's cool I'm trying to put lithium in my 2003 class C don't no where to start

[victorlopez]

Thanks for the Info - I've been doing researching on the Lithium Battery changeover and I keep finding more and more changes that I needed to make from the Converter/charger (which won't charge Lithium batteries to its requirement of 14.6) to this (BIM) and I have no clue where it is on my 2019 Jayco Redhawk SE 22C model- My batteries are located under the stairs which I need to modify also to able to fit the Lithium batteries I want....Far as batteries go they are a LOT of make, models and sizes to choose from Battleborn (too expensive ) to Chins which I find are more affordable..Still doing research but I have plenty of time to make my decisions....PS - forgot to add a 'SHUNT' ...I'll be checking out your website for more info..😁 Thanks again

[fratermus]

LiFePO4 will charge to 100% at 13.8v, which would be fine for them and the chassis battery. Maybe a configuration like this could have used the original BIM, saving ~$150 on the Li-specific BIM and 2 hours of hard work. :-)

What's the rating of the alternator and what kind of charging current do you observe going through the Li-BIM? People think LFP is a black hole of current, but in my digging it seems like when the NEG return ("ground") goes through the chassis there is enough resistance to limit LFP accepatance to 0.33C, or ~66A for 200Ah. Will be intersting to see what numbers you are seeing.

[johndodi]

One thing I’ve noticed after installing the new BIM and lithium batteries that I need to keep the rv plugged in shore power because the Coach battery will continue to draw down from the house batteries to when the rv is parked. I’m thinking that is because of the higher voltage from the house batteries keeping the lower Coach battery charged.

[OldManandtheSuperC]

You can get red or black shrink tube. Let’s you color code a cable end no matter what color you have on hand.

[voyagerman]

Thanks for the video. I’m planning to do this on my 2001 class B coach, but was curious if signal wire is needed if you don’t have an emergency start. I don’t think I have that feature or at least I don’t know how I’d even use it if I did. :) thanks, again.

[jassdsu]

Thanks for making the video. I’m doing a similar upgrade. I noticed you are using 2/0 wire. My battery box has 2 gauge wire- did you upgrade all your wire? I was researching wire size my setup and it suggests my original 2 gauge is sufficient but curious how you did it?

[stevekuiper]

Nice vid. I wish this device had some built-in alternator temperature compensation circuit to throttle down/disconnect in case of ALT overheating. Curious how they arrived at the 15 min on and 20 min off scenario described in their user's manual. I've read that the LFP banks will sponge up a huge amount of current and not knowing the ALT case/winding temp is concerning for DIY enthusiasts. Thoughts?

[mikehall]

Thank you Lou for this video. I have the same set-up in our FR Sun Seeker Class C. Yours was the only video and online information I could find that represented what we have, ie. BIM + separate Solenoid. I have a question. We do have the emergency boost/start switch but this year either the switch or something past the switch towards the chassis went bad as the chassis battery started to drawdown on the coach batteries, so I disconnected it and that resolved my issue. I don't use or foresee using the emergency jump switch and in fact hear that LiFePO's don't have the cranking power to boost the chassis battery/motor. So my question is, do you think the LI-BIM 225 would work fine without connecting the emergency boost/start signal wire?

[davidpearson]

I'm noticing that your link points to the same product I ordered from Amazon. My LI-BIM 225 arrived in a sealed clear plastic bag, and it has 'Gen-2' labeled above the LI-BIM. Is this how the product is typically packaged? My batteries should be in next week. I am installing in a 2024 Sunseeker.

[johnmcclure]

I'm replacing my marine out on my travel trailer and don't know which wire is my ground or power I have a white black and a bare wire any ideas

[danfrank]

Thanks Lou! Great videos - really appreciate you. Question - I have a very similar setup to yours in my Dynamax Isata 3 motor home. Upgrading from AGM to Lithium and my BIM looks identical to yours. I ordered the same replacement LI-BIM you’re installing in the video. BUT - after seeing your struggle with making this thing fit, was wondering if a product like Renogy’s DC-DC charger (which also acts as an isolator) may be another option? And maybe I’m just trading one challenge (small space in the battery control box) for another (routing cables from the DC-DC charger where they need to go)?

[SuleyRivera-yd]

I have a question. I have a 2009 winnebago chalet and the selonoids are placed in a different part than yours. They are also not as nicely labeled as yours. I am having a hard time finding the cable that will be attached to the sig, which I am assuming is the cable for the battery boost in the front. would you happen to know where I can get that informaition. I tried looking up the wiring diagrams but I don't see this type of wire going all the way back to the solenoids. thanks in advance I'll take any information you can provide.