Upgrading battery system to run Norcold for four days?

Lyndall

Been reading all the threads here about the power hog Norcold problem-a problem I need to fix. Am asking for confirmation and/or correction on what I’m reading:
1) renology smart lithium battery…is it true that there are no adaptions needed to hookup when replacing 12v?
2) 140 watt solar panel. Good to know that lithium can be charged with solar (and that 140 w is the smallest to go with). Question: does the towing vehicle also charge lithium via 5-pin? Does shore power charge lithium?
3) is there a better way to solve problem, like replace Norcold with cooler that has dual power source (including propane?)
thanks for your advice!!!!

JamesDow

 
My setup has been my 2018 standard T@G, Norcold NF-30, 100Ah Renogy Lithium Battery and 100-Watt Renogy solar suitcase. I have supplemented my setup with a 60-watt solar panel to charge up phone, camera, usb fan, etc.
When I replaced my battery, my new one lithium did need to go into a larger plastic battery box (Group 31). Besides that, no other changes were needed.
I initially bought a Renogy Lithium 100Ah battery with a monitor attached. My latest battery in a box is a Li Time 100Ah. The Renogy is nice, but at a cost. 
The on-board T@G converter will get the lithium battery to around 83% without a load. With the Norcold running it will charge the battery up to around 94%+.
I would not change anything in the T@G. I do have a small 10A Eco Worthy lithium battery charger ($70), which I do use if hooked up to shore power can top things off.
For a four-day outing with sun, you should not have any issues with 140-watt solar panel setup. In fact, for four days, you may not even need solar. For anything longer, I would suggest increase panel capacity to at least 200+ watts.   I am very pleased with my purchase of a bifacial solar panel from EcoFlow.
I bought it at $380 and it has performed per specifications and over. In fact, it is the only panel I own that will meet and exceed the rated specifications. 
As for charging from the tow vehicle. I have a 2012 Toyota RAV4. I found that I could get around 11% State of Charge increase for every 200 highway miles. It really is not that much of a benefit, except on cross country trips.
I would not replace the Norcold. I love how mine has performed.
The thing to keep in mind is the other draws, like the Fantastic Vent overhead fan and water pump. I typically use 9" battery powered USB fans and they do the trick, even in desert camping.
Before getting my Ecoflow 220-Watt Bifacial solar panel, my best in 95+ degree desert camping has been around 10 days.  Had I had full sun every day, I could have got the 12 days I was shooting for. That 12-day test solo trip was going without any re-supplies, including water.
Bottom line changing to lithium was my best modification.
I have since built a separate power box that has a LiTime 100Ah battery, Victron 30A MPPT charge controller and 400-watt Bestek Inverter.
This new system is built to be able to use each component individually, together or pass through to the T@G.
For my next long trip, I will take the new power box, doubling my battery capacity to 200Ah, giving me a best-in-class MPPT Victron solar charge controller and giving me the option to power other small devices, such as my projector or charging up my two Lectric folding 3.0 bikes.
I do have a 900-watt propane generator made by Baja or (Ryobi) which can power all my needs, even my Danby air conditioner. I rarely ever use or bring it camping.
Have fun making your modification.
 
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Lyndall

Thank you JamesDow!! Really appreciate the information and advice 

Lyndall

Oops , a few more questions …
1) re: use of the Eco Worthy Charger-do you use that to ‘trickle charge’ the lithium battery when TAG is in storage? Do you have to take battery out of box to charge during a camping pitstop? If camping with shore power do you also top off battery with charger?
2) since I’m starting from scratch should I just get the bifacial solar suitcase? Is it compatible with the Renology smart lithium?
3) don’t expect you to know the answer to this, but tow with a 2020 RAV4 hybrid. I wonder if the charge per miles is similar….

thanks again - I’m a total newbie RVer (most of life a long distance backpacker 😉)

JamesDow

@Lyndall,
There is really no need to trickle charge a lithium battery. The power loss over time is extremely low. I charge my lithium battery using the solar SAE connector port built into the front tongue storage box. Just make sure you know which side of the plug(s) are positive and negative. I switch my wires running to my lithium battery during my install. You can easily just get an adapter to reverse the polarity. So no, I never take my battery out of my storage box. When camping with shore power, I have used a battery charger to assure I got up to 100% State-of-Charge (SOC), but only because I knew I would be off grid for an extended period following.
As for upping your system with another solar panel, I would hold off and see how your needs develop. If just camping off grid for 3-4 days, adding just a lithium battery may meet your needs. If wanting to go for longer periods, then increasing your solar capacity may be in order. Nearly all solar panels/solar controllers will work to charge a smart Renogy battery. If adding to an existing solar panel, then you would want to match the DC voltage output of the panels and likely run them in parallel.
I do not know the difference between the alternators of my 2012 RAV4 and a 2020 hybrid RAV4. If you spoke to a dealer, they would not recommend charging a trailer with it, unless it had a towing package (stronger alternator). There is a danger of stress to the alternator, especially in stop and go traffic. If you are serious dependent on charging from your tow vehicle, I would suggest getting a DC-DC converter for your Tow Vehicle (TV).
I would recommend moving in steps. 
Survey your power requirement/needs. What type of camping do you do and what would you like to do?
Do you really need to run the Fan-Tastic Vent Fan on high for extended periods, is running the water pump often really needed?
Upgrade your battery. 
Take a few test trips.
Remember you do not check a lithium battery SOC the same way you would with a lead acid battery.
If you find you are running out of power when you are camping, then increase your solar panel output. Keep in mind that you may want to have/use solar extension cables with sufficient wire gauge size as to not lose too much voltage/power. I would suggest minimum AWG 12 or 10.  I use 12AWG for 20'+10' runs. The extension cables come in handy when you want to park the T@G in the shade and have your panels in the sun.  Remember, getting the most out of your panels may require moving them multiple times throughout the day for the best sun.
Bottom line is to have fun and have less worry of running out of power.

Search this site and other internet sites for lots more information.
Alway feel free to ask questions. That is the beauty of this forum.
Best of luck.
 
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