Lithium Upgrade

[jonnshell30]

Good evening, and Happy Thanksgiving! I pray all had a blessed time with family and friends.
We own a 2005 Journey 36G. It has the original Dimensions inverter. I am wanting to upgrade to lithium batteries, but, due to cost, want to upgrade the inverter, and eventually, solar, in stages.
1) does the Dimensions inverter/charger support lithium
2) is there a mod I need to do to the alternator charging from the engine?
3) on the wiring diagram, I see a charger, but cannot actually find it. Any ideas?
Thanks very much!

[Ron Postma]

1. Your 2005 inverter/charger will not properly support Lithium batteries
2. You need to install a Lithium BIM (Battery isolation Manager) or a DC to DC charger
3. Your charger is the inverter/"CHARGER"

1A You could disable the charger in the Inverter/charger and install a separate Lithium compatible charger.

[larrye743]

I upgraded to 2 Lithium batteries from Costco, mainly because my controller/charger was burning up batteries by overcharging. Also, I am not into getting down on the floor to check the batteries. The battery compartment on my 2008 Itasca Cambria is below the floor, so had to close up some of the openings with tape so far. Upgraded the converter/charger with a compatible replacement (about $200) that has a jumper to support Lithium. I bought a DC-DC charger but have not installed it yet, but I did disconnect charging from the chassis alternator.
The Lithium charges faster and has much more usable amps, so plugging in periodically or running the generator will charge the batteries. I have not installed any solar at this point.
I also lost the ability to cross-connect engine and house batteries for an alternate battery boost. I bought a combo battery jump unit with air compressor so that I can jump my engine battery if I need to.

[Isaac-1]

I just recently upgraded my 2002 Safari Trek to LiFePo4, so was where you are now not very long ago. I ended up going with a pair of 200 AH (actually 210 AH) drop in batteries with bluetooth smart BMS, along with a 50 amp Renogy DC-DC charger with MPPT solar charge controller built in (I already had 400 watts of solar on the roof and an older PWM solar charge controller). In my case I was able to use my existing Progressive dynamics converter which was installed by the previous owner to replace the dead Freedom Combi-10 inverter/charger.


Along the way doing my research I found a lot of people will tell you that you must have a Lithium specific charger/converter, this is often not the case, though it depends on the charge profile of your specific brand and model of unit, and if it will play nice with LiFePo4 batteries regardless if it was "designed" for lithium or not.


Browsing over the Dimension Inverter manual dated 2006, it appears there is no way to disable conditioning mode which runs about every 30 hours, and outputs up to 15VDC, which is too high for LiFePo4 batteries. If not for this, it looks like the sealed lead acid charging profile would work for Lithium batteries, if the charger senses them correctly.


Ike

[jonnshell30]

Thanks everyone.
So what it sounds like is get a new inverter/charger to replace the original equipment, and a DC-DC charger to splice into the alternator connection. Most batteries come with BMS installed, so that part is covered. The only thing I'd have left is solar panels and charge controller when I want to install the solar side.
I appreciate all of the info. I have read articles and watched yt videos, but most make it quite confusing.

[twinboat]

You don't want to limit the alternator output to the chassis battery and systems, only the house batteries.

The house batteries are charged from the charging chassis batteries, not from the alternator.

The battery to battery charger needs to go in that circuit. That's also the circuit used for boost starting and uses battery cable size wires.

[jonnshell30]

Originally Posted by twinboat

You don't want to limit the alternator output to the chassis battery and systems, only the house batteries.

The house batteries are charged from the charging chassis batteries, not from the alternator.

The battery to battery charger needs to go in that circuit. That's also the circuit used for boost starting and uses battery cable size wires.

Got it! Thanks for that!!

[Kenvb]

we have International truck dealers that have 850 amp batteries on sale for $88 plus core.. i put 3 in chassis and 3 in RV part, the old 12 valve cummins turns over so fast now,it starts in seconds,,no more cranking and cranking..and we can cold camp for 7 days before the lights on the battery monitor go down one. 12 days it goes down 2 and i start generator for hour to go back to full charge.
but we only use a 110 TV with power convertor . nothing else 110.

[SCVJeff]

Start by upgrading to a top notch inverter/charger. You will be so much happier with a real PSW inverter you can’t imagine. I think the Magnum MS-series can accommodate Lithium with the Custom charge parameters but not sure. My Magnum treats my FLA batteries so well they may never wear out. The smartest thing I did in that coach was pull the Dimensions

[Our05Winneba]

Be careful what others are saying - there is some confusing / misleading information in other replies.

1) Converter. While the OE Dimension unit may work, as others have suggested it is best to upgrade to a Lithium specific converter, such as a Progressive unit.

2) Engine charging. Many others have strongly cautioned against connecting Lithium batteries directly to the engine alternator charging system. This is because Lithium batteries can take a charge much more quickly than FLA batteries, and can easily overtax the alternator - burning it out. That is why so many recommend a DC-DC charger. One has to be correctly wired into your system to ensure all engine charging goes through this unit, but yet still allows the Battery Boost solenoid to work correctly if needed. I got a Renogy unit which works well. Got the smallest 20amp model as that is all I needed because when we travel it is for many hours at a time, and that works great in conjunction with our rooftop solar - which also charges while we drive.

3) Adding solar these days is relatively easy and inexpensive - far cheaper than the LiFePO4 batteries.

4) You should really add a good battery monitor (such as the Victron 712 - though other similar Chinese made models are also available) because you really need to know an accurate charge state of your batteries. This type of monitor provides tons of other information (such as current rate of charge / discharge) and is really worthwhile. Unlike FLA batteries it is much more difficult to determine state of charge on Lithium batteries by voltage alone - so this type of monitor is really needed.

[Isaac-1]

I agree mostly with the above post, but would like to add a point:


4B - A separate battery monitor may not be needed if you get a set of batteries with a built in Smart BMS with Bluetooth, as the smart BMS duplicates many of the features of an external battery monitor and will display to your phone or tablet.

[14OTR]

Hello and I'm hoping some here can give me some good advice. I have a 2005 Tioga 22B. I am replacing the 2 T-105's with a renogy 170 AH LiFePo4 for the cabin. I have replaced the Charger/Converter with a PD9145AV(lithium charger). My chassis battery boost has never worked so that is disabled. I'm told that I should disconnect the LiFePo when running off of shore power AFTER battery is fully charged. Am going to install a Victron BMV-700 to monitor charge and usage. I do not do much boon docking but when I do, I plan on using generator and portable solar to keep battery up to snuff. So my two main questions are 1. Can I disconnect the alternator charging to the LiFepo, and, 2. can I use the on-board Intellitec Bi-Directional Isolator Relay Delay(model 00-00362-100) to 1. disconnect the LiFePo from the Charger/Converter when fully charged from shore power by turning off cabin battery switch and, 2. disconnect LiFePo from chassis alternator by turning off cabin battery switch?