Need to add Lithium Batter and charger to 2019 RP1 - Event Date: 23 Jan 2023 - 23 Feb 2023

There are already a couple of contactors under the hood that are connected into to the existing circuits between the house and start batteries, so I think one already activates when the ignition is turned on. All Id likely have to do is connect the input to the DCDC to that. I can buy a DCDC and do that later on if I find I need to.

The other contactor activates when I push an emergency start switch on the dash, allowing the house batt to be used in parallel to help start the engine. That is a nice feature that I'll lose, can't parallel a Li with a Pb battery. I might be able to partly replace it though by charging the start battery from my new inverter/charger, which I found out came with two separate 12v charge ports, one big 100 amp one for the house battery and a second low current trickle charge one for a second (usually starter on a boat engine) battery.

It's a 2kw Mastervolt inverter/charger and has generator/shore power support, meaning its inverter function will kick in to help run loads that might be too high for the generator or shore power by itself. Any excess power at low load will charge the battery if the gen/shore is on and if it's off the inverter will run the loads.

Seems like a pretty nice unit, got it on Walmart online for a very reasonable price. Haven't had a chance to run it yet though. You might want to check it out if youre considering getting an inverter at all. it'll charge the battery up to twice as fast as the WFCO.

According to the description in the Chinook manual there's also a low voltage disconnect in there somewhere, that I'll also have to find and remove as it wont be set up right for lithium.

Got it, thanks for the clarification. For sure, you need to isolate the Li battery from the risk of overcharge from the alternator circuit.

I'm thinking about what I want to do to connect the vehicle start circuit on my Chinook to the Li system Im installing in the coach. If anything.

Same set of issues except it will be hardwired rather than go through a connector.

Right now I'm inclined to keep things simple and have no connection. I'll have a big solar array plus a generator for backup so probably won't ever need to use alternator charging anyway. Saves buying a DCDC converter.

Originally posted by StephenH Check my mods (link in signature). I have done what you are proposing. I have written it up with pictures. You did not say which model RPod or more specifically, which model power center you have. If you have the WFCO-8955, you can swap out the converter section for a WFCO-8950L2-MBA, which is the proper board for Lithium batteries. That is what I did. I also installed a Renogy 20A DC to DC charger. I chose to run a dedicated 12V circuit for the TV and the RPod to power this and disconnected the wire from the Bargman 7-way connector at the junction box under the front corner. If the TV you have has a heavy-duty enough wire running for that, you could disconnect the wire and then run a dedicated line from that point to your DC to DC charger as Offgrid suggests. The way I did it, I have a battery isolation solenoid so when the truck is shut off, the circuit is not energized so it can't feed back through to the TV.  I did all of this because the Frontier has an "intelligent" charging circuit and the LiFePO4 battery was fooling it into thinking the battery was charged. I would arrive with the LiFePO4 battery at less of a charge than when I left the house. With the separate circuit, this solved the problem and both the Frontier and RPod get properly charged.

StephenH, while the rest of your Li conversion write up is right on the money in my book, I'm not understanding your reasoning for needing to install a separate connector for your Li battery from the TV.

We've had this discussion before a bit but there still seems to be some confusion. Maybe just on my part.

I'd like to get to the bottom of it because I think that extra connector is a complexity and potential failure point that will be a turn off for many folks, and I've not heard of other folks needing to do it.

A DCDC converter connected at the trailer side of pin 4 should give you up to 30 amps (the Bargeman connector current limit) which should be plenty for most uses, without needing another connector.

You can either feed that pin on the TV side through the existing conductor, or if that doesn't supply what you need because of current limitations or a confused intelligent charge circuit or some other reason, you can disconnect it and run another 10 gauge wire from the TV battery via a 30A thermal reset breaker. That is standard materials and procedure when you install an aftermarket 7 way trailer connector kit, Ive done it on 3 or 4 TVs now, probably you have too.

Wouldn't you have to do the same thing with a separate connector to the trailer anyway? Sorry but I'm just not seeing how a second connector adds any benefits unless you need and your alternator can safely deliver more that 30 amps charge current.

Sorry, TV in this case means Tow Vehicle, not Television.

Check my mods (link in signature). I have done what you are proposing. I have written it up with pictures.