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Lithium Battery Upgrade from AGMs for RV house battery bank

DrJer

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Sep 18, 2021
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Decisions, Decisions, Decisions… (AGM replacement vs. Lithium upgrade)

Well, it is time to replace the house batteries on our 2009 Magna as the six LifeLine AGMs are dying off and only work maybe 5hrs overnight with just refrigerator running before generator attempts to auto-start. Our coach is full-electric (no propane) with six 8D AGM house batteries, and also has the 400w solar package add-on. The current batteries are 6+ years old.

I am doing my research to possibly upgrade our system in steps: 1st – lithium batteries, 2nd – hybrid converter(s), 3rd – solar system upgrade.

As a conversation starter, I am looking into initially switching over to lithium batteries and adding the necessary components to do this first step. BTW, we rarely ‘boondock’ longer than 1-2 days and we also plan to have this coach 10+ years. Just looking for a nice balanced dependable system, not a full blown ‘off-grid’ system. I don’t mind running the generator on occasion, just would like dependable overnight battery use of refrigerator (plus furnace if necessary) and refer plus heat or one A/C during day.

LifeLine GPL-8DL are about $750ea. They are rated 255ah, so our original six (6) house battery bank had 1530ah. We have only had the coach about a year, and therefore never got to experience new-condition AGMs. Research states AGMs are only about 50% efficient overall, so even at best when new have about 765ah of true usable capacity out of six 8Ds. (replacing 6 AGMs approx. $4500)

BattleBorn BB8D are $2259 each currently. They are rated 270ah each, have same dimensions as AGMs, and are stated to be 80% overall efficient and last 10+ years. So my initial thoughts would be to start with three (3) BB8D for 810ah in the house battery bank. Their stated 80% efficiency would yield 648ah usable capacity out of three batteries. (cost of 3 BB8Ds approx. $6800)

Yes, I am aware there are less expensive lithium battery options; but right now Battle Born gets my vote as their customer service has been the most helpful of any contacted. They have guided me to setting a ‘Custom’ charging profile on our existing dual Xantrex RS3000 inverters so I can use our existing inverter / charger until upgrading to recommended Hybrid unit(s) in the future. They also instructed me that I would have to replace our existing charge solenoid with a Lithium Battery Isolation Manager (Li-BIM) or a DC-DC charger to protect alternator from being overworked / damaged from lithium battery draw. Our alternator in the coach is rated at 320amps.

Sounds like I could also use our original equipment HelioTrope solar controller for a while, but would benefit from replacing with a modern MPPT unit.

So my initial question to this group is… have any of you with a similar coach to ours switched over to lithium batteries for your house bank? Pros / Cons?

Any advice or input would be appreciated as I’m just beginning my research. Dr Jerry
 
Well, IF you had the budget to go to BattleBorns and IF you get the right charger thingy to not fry the coach and IF you're comfortable reprogramming your controllers and inverter then it's a good option.

Having said that, paying over $2,200 per battery HURTS just thinking about.

Reprogramming a dozen tewaking options into the rest of your system to not kill anything scares the hell out of me. What's the point of a drop-in replacement if you can't just drop it in, maybe changing the SEALED to LiFePo4 option in the controller and walking away?

My gut tells me that you could find other LiFePo4's in the same rating for cheap enough that you could upgrade your existing controller to one that's LiFe ready, replace your DC-DC charger AND still afford sandwiches.

Now, I'm not saying to go for the bargain basement ChingDongWang batteries from AliExpress, but there are many other reputable battery companies out there selling comparable batteries for about half the price as the BattleBorn's.

But that's just my $0.02
 
First question from me:

Is your fridge a compressor type or absorption type that can run on propane?
 
the HelioTrope solar controller will need to be changed to a lithium profile

i would say no question, change to lithium, there are other benefits, not just capacity i.e. steady 13.2V throughout it's useful capacity, less weight
as long as the IF's in the previous reply are met

mark
 
Hello DrJer. I am very slightly ahead of you in your quest to go Lithium. I recently DID replace 4 LifeLine 8D AGMs (1000Ah roughly) with 3 LifeBlue LB12300LTs (rated 900Ah) in my 2007 CC Allure with great success. Well, almost. Everything works well with my 1700 watt solar setup. But, the original Magnum MS2812 inverter/charger only supplies 125 amps maximum when charging my lithiums. So, I added an RS3000 that I removed from my previous RV, a 1997 Monaco Windsor (reinstalling it's original Xantrex Freedom 2000 inverter/charger before I sold it). My hope was that by installing it in my newer RV, that would provide an additional 150 amps of charging capacity to supplement the 125 amps provided by the original MS2812. Xantrex Tech Support recommended I select GEL as it's the best lithium-compatible choice from the battery selection menu. Therein lies the problem; the Xantrex has never provided more than 25 amps when the MS2812 supplies it's max at 125 amps, even with a battery SOC as low as 40%. Anyone have any suggestions to 'fix' this problem?

felix
 
Decisions, Decisions, Decisions… (AGM replacement vs. Lithium upgrade)

Well, it is time to replace the house batteries on our 2009 Magna as the six LifeLine AGMs are dying off and only work maybe 5hrs overnight with just refrigerator running before generator attempts to auto-start. Our coach is full-electric (no propane) with six 8D AGM house batteries, and also has the 400w solar package add-on. The current batteries are 6+ years old.

I am doing my research to possibly upgrade our system in steps: 1st – lithium batteries, 2nd – hybrid converter(s), 3rd – solar system upgrade.

As a conversation starter, I am looking into initially switching over to lithium batteries and adding the necessary components to do this first step. BTW, we rarely ‘boondock’ longer than 1-2 days and we also plan to have this coach 10+ years. Just looking for a nice balanced dependable system, not a full blown ‘off-grid’ system. I don’t mind running the generator on occasion, just would like dependable overnight battery use of refrigerator (plus furnace if necessary) and refer plus heat or one A/C during day.

LifeLine GPL-8DL are about $750ea. They are rated 255ah, so our original six (6) house battery bank had 1530ah. We have only had the coach about a year, and therefore never got to experience new-condition AGMs. Research states AGMs are only about 50% efficient overall, so even at best when new have about 765ah of true usable capacity out of six 8Ds. (replacing 6 AGMs approx. $4500)

BattleBorn BB8D are $2259 each currently. They are rated 270ah each, have same dimensions as AGMs, and are stated to be 80% overall efficient and last 10+ years. So my initial thoughts would be to start with three (3) BB8D for 810ah in the house battery bank. Their stated 80% efficiency would yield 648ah usable capacity out of three batteries. (cost of 3 BB8Ds approx. $6800)

Yes, I am aware there are less expensive lithium battery options; but right now Battle Born gets my vote as their customer service has been the most helpful of any contacted. They have guided me to setting a ‘Custom’ charging profile on our existing dual Xantrex RS3000 inverters so I can use our existing inverter / charger until upgrading to recommended Hybrid unit(s) in the future. They also instructed me that I would have to replace our existing charge solenoid with a Lithium Battery Isolation Manager (Li-BIM) or a DC-DC charger to protect alternator from being overworked / damaged from lithium battery draw. Our alternator in the coach is rated at 320amps.

Sounds like I could also use our original equipment HelioTrope solar controller for a while, but would benefit from replacing with a modern MPPT unit.

So my initial question to this group is… have any of you with a similar coach to ours switched over to lithium batteries for your house bank? Pros / Cons?

Any advice or input would be appreciated as I’m just beginning my research. Dr Jerry
Go lithium and never look back.

In your coach's power center there is a "converter charger" that charges your batteries while on shore power. You can usually leave the power center and swap out only the charger portion. If it's a WFCO unit they make a lithium charger upgrade. I have swapped a few, super easy to do with basic mechanical skills. Mine for my new RV is sitting on the kitchen counter. This upgrade will make sure your lithium batteries are properly charged while on shore power. Progressive dynamics also makes these. An inverter charger is an alternative option but if you already have an inverter it would be a waste of money to throw it away.

A DC to DC charger is also in order for charging your batteries off your alternator while the coach is running. One of these will ensure you aren't putting undue stress on your starting battery or alternator. Size this properly.

You could leave your current solar controller and upgrade it when you do your solar upgrades.

Get a great battery monitor. The victron BVM 712 is hard to beat. Generally where possible I'm only using battle born and victron from here on out. Amazing kit.

Pros/Cons: Lithium just beats the snot out of any flooded battery. Getting so much more Ah out of the size and weight is amazing. The ONLY con for ME since I live in MN is the cold. Good batteries have charge/discharge cutoff in them for temp but if I want to be able to use my RV I have to run heated batteries. With solar this wont likely be an issue as the sun should run those battery heaters no problem. But temp can be a thing with lithium.

Go lithium, never look back!!
 
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