12V Lithium vs 6V deep cycle batteries

[nsdtr3]

Hello RV'ers,

We have a Montana 40ft 5th wheel with 4 - 6volt Trojan batteries and they lose charge and we have to jump start the batteries to turn on our generator to recharge the batteries. We do have solar panels but the RV is stored under a a roof where no direct sun hits the solar panels, just ambient light from the rear and front of the RV. Wondered about changing to Lithium batteries like the RELiON 12V 300Ah Lithium Battery
Item No. 122875
sale price $3,429.99 was $3,488.95

The 6 volt batteries say 225 AH @ 20 hr - 185 AH @ 5 hr.

Which set up gives me the most energy and will the Lithium lose charge as quick as the deep cycle batteries?

Thanks for the help and advice,
John & Marie

[AZ Traveler]

John,

Is your battery bank running down in storage or only with a load on it? Have you added a total battery disconnect to your system?

The 300 ah lithium will provide more power than the Trojan's which should not be taken below 50%. If you don't have a total disconnect you will have the same issue in storage.

[nsdtr3]

Hi Zack,
we did have a separate kill switch which shuts off power to the whole unit. When we had issues with the batteries discharging to the point where we couldn't use the jacks we realized the power on/off switch in the water valve section didn't shut all power off so we had the kill switch installed. We have always had the issue of batteries discharging even with the kill switch. Monthly I'm adding distilled water to the batteries and have to jump the batteries and start the generator to charge the batteries. So now it's time to find a dealer or RV repair shop that installs the batteries and appropriate monitors. We do have a magnum inverter and have solar panels too.

[nsdtr3]

Here are pics of our batteries

[kowbra]

Originally Posted by nsdtr3

Hello RV'ers,

We have a Montana 40ft 5th wheel with 4 - 6volt Trojan batteries and they lose charge and we have to jump start the batteries to turn on our generator to recharge the batteries. We do have solar panels but the RV is stored under a a roof where no direct sun hits the solar panels, just ambient light from the rear and front of the RV. Wondered about changing to Lithium batteries like the RELiON 12V 300Ah Lithium Battery
Item No. 122875
sale price $3,429.99 was $3,488.95

The 6 volt batteries say 225 AH @ 20 hr - 185 AH @ 5 hr.

Which set up gives me the most energy and will the Lithium lose charge as quick as the deep cycle batteries?

Thanks for the help and advice,
John & Marie

T-105s are great batteries; we used them for years. But they are no comparison to Lithium.
Here is some simple math (maybe you know this...)
-4x 6v/225ah = 900ah@6v = 450ah@12v. So your total 12v capacity is 450ah.

-FLA batteries should not be discharged below 50% or you will severely limit their lifespan. So your usable capacity is 225ah.

-last note; FLA batteries can only charge at about 20% (.2C) of their capacity, whereas Lithium can charge at 80-100% (.8C - 1C). IOW, Lithium will recharge in ~1/4 of the time.


So, to your question:
-300ah Lithium will have more energy and will be able to both discharge faster (to run surges like AC) and to recharge faster (run the generator far less)

-will the Lithium lose charge as quick? Sort of... it does have more energy, so will go longer before completely discharging. But, you have a drain on your batteries, and eventually even the biggest and best batteries will be dead.


If you are spending the money to change out batteries to Lithium, I would highly recommend looking at installing a battery monitoring solution, such as the highly rated Victron BMV-712. This will help you understand the amount of energy being drained, and which draws are happening when. From there, you can start isolating and shutting off those sources of draw. It will also allow you to know when to run the generator to prevent total discharge.


HtH!
Brad

[nsdtr3]

Thanks Brad,

I'm trying to find an RV dealer here in the Willamette Valley of Oregon that sells and installs the Lithium Battery and now I'll add " I would highly recommend looking at installing a battery monitoring solution, such as the highly rated Victron BMV-712"
Thanks again,
John

Any suggestions on where to buy and have them installed?

[carlrx7]

I went with two DIY Game Changer 280ah batteries. Did one in April and found out two would fit perfectly.

My RV pulls 2 watts with the battery disconnect set. Batteries drain about 4% per week (inverter off, leveling jacks, propane, victron).

Hope this helps.

P.S. Lithium batteries don't like being store at 100% SOC. They are much more happy between 35-70%

[kowbra]

Originally Posted by nsdtr3

Thanks Brad,

I'm trying to find an RV dealer here in the Willamette Valley of Oregon that sells and installs the Lithium Battery and now I'll add " I would highly recommend looking at installing a battery monitoring solution, such as the highly rated Victron BMV-712"
Thanks again,
John

Any suggestions on where to buy and have them installed?

The experts on solar for Montana 5th wheels are Future Sales in Indiana. If you want to get in touch, Matt Wolkins is the guy - matt@futuresalesrv.com

They are the designer and builders of the Super Solar Flex system that Montana installs as an option. I have that system, and have reached out to MAtt for information and some upgrades. Recently, I wanted to upgrade my solar controllers; they shipped from the US to Canada within a week, and sent along easy to follow instructions. I've heard of others, including on this forum, who have travelled there and had installations done as well.

Very good to deal with in my experience!

Brad

[Carl n Susan]

[QUOTE=nsdtr3;1226358]Hi Zack,
.... When we had issues with the batteries discharging to the point where we couldn't use the jacks we realized the power on/off switch in the water valve section didn't shut all power off so we had the kill switch installed. We have always had the issue of batteries discharging even with the kill switch. Monthly I'm adding distilled water to the batteries and have to jump the batteries and start the generator to charge the batteries...... /QUOTE]
I guess I don't understand. The batteries should maintain their charge for months with a kill switch. You shouldn't have to add water to batteries that are disconnected. And with the current technology converters, you normally only need to add water ever 4 -6 months.



I think there is a problem with your batteries. How old are they and how many times have then been discharged below 50%? Perhaps testing them would determine their health.



As for lithium batteries, I don't think your 2017 converter is compatible. It will charge them but slowly and not to 100%. And I wouldn't discount the converter as the cause of your current battery problems.

[nsdtr3]

Thanks Carl,

I'll have the RV service center check both the batteries (which have discharged fully many times) and the converter. We have a magnum inverter/converter.

Thanks for the advice,
John

[nsdtr3]

Thanks Brad,

Good info,
John

[nsdtr3]

Thanks for the info everyone.
We ordered : (4) 100 Ah 12V LiFePO4 Deep Cycle Battery

$949.00 $899.00

and also a Victron BMV-712 Battery Monitor

After install and a few months pass I'll post my review of the products,
John



John and Marie Simonson
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[nsdtr3]

Purchased 4 Battle Born Lithium Batteries and Battery monitor gauge. Install in a few weeks at Camping World Wilsonville Oregon.

[Speck56]

Originally Posted by nsdtr3

Here are pics of our batteries

Here's what I do. Stored under a roof so no solar. However the storage space has 110 plug, so I have a lithium battery charger hooked up and when the facility turns power on to my row every night for 3 hours it keeps my batteries near 13.2 volts.

[RVDH]

Originally Posted by nsdtr3

Hello RV'ers,

We have a Montana 40ft 5th wheel with 4 - 6volt Trojan batteries and they lose charge and we have to jump start the batteries to turn on our generator to recharge the batteries. We do have solar panels but the RV is stored under a a roof where no direct sun hits the solar panels, just ambient light from the rear and front of the RV. Wondered about changing to Lithium batteries like the RELiON 12V 300Ah Lithium Battery
Item No. 122875
sale price $3,429.99 was $3,488.95

The 6 volt batteries say 225 AH @ 20 hr - 185 AH @ 5 hr.

Which set up gives me the most energy and will the Lithium lose charge as quick as the deep cycle batteries?

Thanks for the help and advice,
John & Marie

Too many problems with Lithium batteries at this point not to mention you need a different charger. They are also prone to being a fire hazard so check with your insurance company first before spending big bucks on batteries. If your Trogan batteries are good and there's nothing drawing them down they should hold a charge for a long time. Lead acid batteries are only good for about five years.

[Speck56]

New technology in lithium batteries, Battleborn, has made them the safest batteries out there. 10 year life, rapid recharge, ability to discharge to 0% with no damage. Expensive, yes, but way too many advantages to ignore. Different technology than cell phone or hoverboard lithium. Will never do lead acid, heavy high maintenance batteries again.

2020 3761FL
2020 GMC DENALI 4WD 3500 DRW

[GreG L.]

Other than price (getting cheaper), Lithium is the way to go. Lithium charges faster, twice the power, more temperature resistant, no maintenance, last many times longer and of course much safer than wet batteries. Lithium can be placed in the living area (under a bed for example) with no off gas, and because they are Lithium iron, not lithium ion they are not prone to fire or other issues as long as they are not abused and tests show even with heavy physical they still don't burn.

[Daryles]

Just be aware, lithium batteries do not like to be CHARGED when below freezing.
If you do any winter camping make sure you have a battery heater for them.
I made my own and kept the original 100Ah FLA battery. This one I can charge in below freezing temperature from my 400W solar panels if boondocking or from shore or generator power. From this FLA the heaters for the lithium batteries operate. Once they are above freezing I can switch charging power to them to charge them up.
BTW I added two layers of 1" pink styrofoam board to the battery compartment.
Excellent article about caring for lithium batteries.
Make them last forever...

How to find happiness with lithium batteries
https://www.solacity.com/how-to-keep...tteries-happy/

[Speck56]

Absolutely. Have a 12v heater blanket on them. Don't do alot in sub freezing. Live in Peoria Az

[djrich]

We have a Montana 3791RD Super Solarflex. I added another 1000 watts for a total of 2000 watts and it came with 6 100Ah Battle Born batteries. We have been living full time since September 2020
in this unit. In that time we have not needed to plug in and our propane usage is only for heat. Mr. Coffee in the morning, induction range and microwave for cooking. More TV than we need. Since going Lithium life is good. The lowest SOC we have seen was 20%. It is nice to not think about batteries!