Factory Solar & Lithium Batteries-Advice Needed

[kim_e83]

Hi All,

We have the factory solar in our 2021 344GK unit. We had two 12 volt batteries installed originally by the dealer. We recently found our batteries were overcharging (suspect faulty converter) and have a service appointment to confirm. If the converter is bad, I'm thinking we will take this opportunity to upgrade to Lithium Ion Batteries and a compatible converter.

Questions.....

We aren't heavy boondockers, but would like the ability to be able to stay a night or two without power and keep our residential fridge running. Is this possible with 2 100 amp hour Lithium Ion batteries and our 300W factory solar panel? If we want to boondock longer, what kind of investment in battery and additional panels would you recommend?

Any recommendation on Lithium Ion Batteries (familiar with Battle Born) and a converter?

Thanks in advance!!!

[bertschb]

Any recommendation on Lithium Ion Batteries (familiar with Battle Born) and a converter?

Battle Born are kind of the go-to batteries for RV use but there are many other less expensive alternatives. I started with two Lion Energy UT1300 LiFePO4 batteries. They worked fine but I didn't like the post design so when I upgraded my factory 300w solar system I switched to two 270ah BBGC3 Battle Born batteries. The post design on Battle Born batteries is extremely robust and build quality overall is second to none. But, Battle Born batteries are among the most expense available.

As for charger/converters, the go-to model for folks switching to LiFePO4 batteries is the Progressive Dynamics PD9160ALV. Again, there are less expensive alternatives.
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

As for how many batteries you'd need to stay a night or two and run your residential fridge - it depends! The items that draw the most power are (typically):
- Fireplace
- A/C
- Electric water heater
- Hair dryer
- Microwave
- Coffee machine
- Toaster

If you avoid running all those and the sun shines during the day and you aren't parked in the shade, you could probably stay indefinitely with two LiFePO4 batteries and the 300w factory panel. The furnace will also use some power but if you run it for an hour or two a day I would think your factory system would keep up. The more you use the high draw items I listed, the less likely you will make it two days. Most people recommend doing an energy audit to determine what your needs are before building a system.

[ajg617]

Battle Born are kind of the go-to batteries for RV use but there are many other less expensive alternatives. I started with two Lion Energy UT1300 LiFePO4 batteries. They worked fine but I didn't like the post design so when I upgraded my factory 300w solar system I switched to two 270ah BBGC3 Battle Born batteries. The post design on Battle Born batteries is extremely robust and build quality overall is second to none. But, Battle Born batteries are among the most expense available.

As for charger/converters, the go-to model for folks switching to LiFePO4 batteries is the Progressive Dynamics PD9160ALV. Again, there are less expensive alternatives.
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

Sorry for bringing up an older post, but our 310GK-R with factory solar just arrived at the dealership this past week. I had been toying with LiFePO4 from the get go rather than having the dealer install the normal lead acid or higher priced AGM only to replace them. However, when I asked the dealer about lithium they said the don't do a lot of that which left me a bit uncomfortable.

With your original Lion batteries, did you simply place them in the existing battery locations? Ditto with the Progressive Dynamics - same location? Not looking for anything more at this point as I have the generator as well.

Reading some of the more elaborate installs on this site, am I missing other components?

Thanks,
John

[huntindog]

Sorry for bringing up an older post, but our 310GK-R with factory solar just arrived at the dealership this past week. I had been toying with LiFePO4 from the get go rather than having the dealer install the normal lead acid or higher priced AGM only to replace them. However, when I asked the dealer about lithium they said the don't do a lot of that which left me a bit uncomfortable.

With your original Lion batteries, did you simply place them in the existing battery locations? Ditto with the Progressive Dynamics - same location? Not looking for anything more at this point as I have the generator as well.

Reading some of the more elaborate installs on this site, am I missing other components?

Thanks,
John

I would add a victron battery monitor as well. You really cannot tell the status of LiFePo4s very well by voltage.
Do that and the basics are covered.

[CFM56-7]

Hello!

I don't want to start a new thread, so I'll tack a quick question here.

I recently bought a 2020 337RLS that I plan to do a lithium upgrade to. I will use a Victron Multiplus II 2X120V unit and two Battle Born 12V GC3 270AH batteries. I have most of the configuration worked out in my head, but there is one element I could use some input on. The Multiplus will provide DC power to the RV with shore power connected, as well as charge the batteries. I know LiFePO4 batteries do best when fully charged and removed from the circuit when not needed. With shore power connected, can I leave the batteries hooked up full time? Are there settings on the Multiplus that will optimize battery longevity? Does the Battle Born BMS do a decent enough job by itself or do I need to isolate the batteries from the 12 volt circuit after they are topped off?

I joined this forum before making a purchase and I can't thank you all enough for the incredible wealth of information shared here.

Thanks,
CFM

[A.Texas.Yankee]

Hello!

I don't want to start a new thread, so I'll tack a quick question here.

I recently bought a 2020 337RLS that I plan to do a lithium upgrade to. I will use a Victron Multiplus II 2X120V unit and two Battle Born 12V GC3 270AH batteries. I have most of the configuration worked out in my head, but there is one element I could use some input on. The Multiplus will provide DC power to the RV with shore power connected, as well as charge the batteries. I know LiFePO4 batteries do best when fully charged and removed from the circuit when not needed. With shore power connected, can I leave the batteries hooked up full time? Are there settings on the Multiplus that will optimize battery longevity? Does the Battle Born BMS do a decent enough job by itself or do I need to isolate the batteries from the 12 volt circuit after they are topped off?

I joined this forum before making a purchase and I can't thank you all enough for the incredible wealth of information shared here.

Thanks,
CFM

As long as you set your Multis to the right specs, set it and forget it. It's common to follow the 20% rule (don't discharge battery below 10% or charge above 90%) but really I wouldn't worry about it.

Full Timing Family
2021 Momentum 395MS-R
2021 Ford F450 King Ranch

[Always Learning]

Hello!

I know LiFePO4 batteries do best when fully charged and removed from the circuit when not needed. With shore power connected, can I leave the batteries hooked up full time? Are there settings on the Multiplus that will optimize battery longevity? Does the Battle Born BMS do a decent enough job by itself or do I need to isolate the batteries from the 12 volt circuit after they are topped off?

CFM

My recommendation is to call Battle Born support and ask them these questions. They have great support and you will get current information about your questions.

[CFM56-7]

As long as you set your Multis to the right specs, set it and forget it. It's common to follow the 20% rule (don't discharge battery below 10% or charge above 90%) but really I wouldn't worry about it.

I appreciate the response! It sounds like you advocate for a battery disconnect of some sort then. I do have a support request in with Battle Born trying to get their recommendation, but haven't heard back yet.

Their web site recommends a float charge of 13.6V or less, which may be their way around the BMS constantly trying to protect an overcharge situation, but then you are keeping the battery at 100% any time shore power is connected.

I'll post their response when received.

Thanks!
CFM

[A.Texas.Yankee]

I have a master disconnect between battery bank and EVERYTHING else. But that is rarely used since we full time so it's really only for servicing or troubleshooting something that I need to cut off the 12v.

Full Timing Family
2021 Momentum 395MS-R
2021 Ford F450 King Ranch

[CFM56-7]

I have a master disconnect between battery bank and EVERYTHING else. But that is rarely used since we full time so it's really only for servicing or troubleshooting something that I need to cut off the 12v.

Battery shutoff will be incorporated for sure. I was ideally looking for a solution to do everything automatically or at least from within the fifth wheel.

Thanks for everyone's input! Battle Born got back to me and confirmed that the lower float voltage is the key to long life of the cell. Their only additional recommendation related to long term use on shore power of 20 days or more. They recommend turning off the DC side of the Multiplus II and let the batteries discharge to 60% or so, then allow to fully recharge so that cell balancing can be accomplished.

It sounds like Battle Born is adding a lot of new Victron products not currently available on their web site. I do believe I will be forking over some cash to them soon. So far I am quite please with their customer service and technical expertise.

Thanks again and happy camping!

CFM