Community Forums

TucsonAZ · 06-09-2022, 07:28 PM

I just purchased an 18.4 Kwh LifePo4 battery bank (don't even have my MH yet) consisting of 3 rack mount 120ah 48v packs.

I would have liked larger and may add one more but this cost enough that I want a month to mentally recover ( :

How large is your Battery Bank, what are you running with it, do you wish you'd bought more and what would you change if you had a do over?

Iceclimber · 06-09-2022, 08:02 PM

6x premium golf cart batteries which is all I can fit in the space with a pair of group 31 starts.

I'm pleased with the performance and price. I have 200 watt solar panels I can deploy and the addition of a VSR really helps keeps them up while driving. I have a 10k very quiet generator and boondock way far away from anyone, so I don't mind running the beast. After all, that is why it's there.

Just out of morbid curiosity what is your investment in the 3 batteries ?

Nwcid · 06-09-2022, 08:10 PM

What are you using to convert the 48 volts to 12v that is needed for your RV?

I have 6, 6v AGM with a total of 675 AH or 8.1 kWh. This is backed with a 3000 watt inverter wired into L1 of my RV and next week I will have 1400 watts of solar.

While I can run 1 A/C with my system, it runs down too quickly. In reality if I need A/C I need both. We do use things like microwave, toaster oven, coffee maker and all the things of daily living including remote working.

In the future, our next rig, I would go with 600-1000 AH of lithium.

Bobby F · 06-09-2022, 08:15 PM

Quote:

Originally Posted by TucsonAZ

I just purchased an 18.4 Kwh LifePo4 battery bank (don't even have my MH yet) consisting of 3 rack mount 120ah 48v packs.

Just for my own confusion: Do you mean you have 360Ah at 48v, or 360Ah at 12v?

TucsonAZ · 06-09-2022, 08:24 PM

Quote:

Originally Posted by Bobby F

Just for my own confusion: Do you mean you have 360Ah at 48v, or 360Ah at 12v?

360Ah at 51.2 Volts (16S) for a total of 18.4Kwh

Nwcid · 06-09-2022, 08:46 PM

Quote:

Originally Posted by TucsonAZ

360Ah at 51.2 Volts (16S) for a total of 18.4Kwh

How are you going to use that with the 12v systems in your RV? Or are you only using this for your inverter and have a separate 12v battery system?

How are you charging your 48v system?

paul65k · 06-09-2022, 08:48 PM

I have 13.3 Kwh of storage which equals 525Ah @24V. We charge with 1600W of Solar and 30A of charging while driving from our DC-DC intelligent charger.

We are wired to run every single thing in the coach including both Rooftop AC units, which we can with dual 3000W inverters. The greatest thing though about our system is the ability to charge the battery bank at up to 140Ah (280 Ah@12V) which get the batteries charged up FAST with either the generator or shore power.

I am planning to upgrade the solar to ~3500W which should give us between 120-150A at solar noon and I can run BOTH AC units with about 130A total.... we typically only run one unit so that means we can run an AC unit and still put 50-70A (100 - 140A@12V) into the battery bank WHILE RUNNING AN AC UNIT.

1600W is good but we still manage a bit..... @3400W I'm thinking it will truly be like being plugged in in the middle of nowhere on a sunny day

Bobby F · 06-09-2022, 08:59 PM

Quote:

Originally Posted by TucsonAZ

360Ah at 51.2 Volts (16S) for a total of 18.4Kwh

Wow.

Okay, to be responsive to your question: In my 28' C, living solo, I have 400Ah (12v) of AGM batteries. I run everything except air conditioning off of them, profligately. TV's, stereos, fans, furnace blower, lights, microwave, electronic chargers, vacuum, induction cooktop, you name it. I charge it off of 600 watts of roof-mount panels. I have found this to be more than adequate capacity - I might get down to 60% on a cold night - the furnace fan gulps power - but I'm generally at 100% by 11am.

The only reason I might increase my power capacity would be if I wanted to run AC without the generator. But I don't like AC, which simplifies everything.

You have a lot of battery capacity.

TucsonAZ · 06-09-2022, 10:49 PM

Sounds like we all have very differently sized and configured systems to address our needs and travel styles.

To address the 12V question, this is all just for supplying 120/240v loads and nothing else. There is more than enough power there for me to run the MH as if I'm plugged in and then when I am plugged in it would run off shore power versus my batteries.

In short, shore power goes into my inverters which are hooked up to my batteries and the MHs AC side. If I'm plugged in I run everything off that, if I'm not plugged in it's all run off my batter bank including the converter/charger for the 12V system.

I don't have a MH yet though so I'll adjust accordingly when I do and hopefully can run the entire thing off 120V although I will have a full sized washer/dryer in my tow behind trailer but I figure I can run that at parks when needed.

astrocamper · 06-10-2022, 10:37 AM

I started with four 100 amp-hour Battle Born batteries. I added 3 more a couple years later. The 700 amp-hours allows us to run the air conditioner off the inverter well past sunset and still have plenty to get us through the night.

I also use the trailer as a power backup for my home when we are not traveling. I don't bother firing up a generator when the power goes out at the house unless the power outage will last several hours past sunset.

CyrusL · 06-10-2022, 01:20 PM

Whether you need more is definitely going to depend on how you use it, but I suspect you won't need more. I have just over 10kwhr and can run my air conditioner for about 7 hours if I'm not getting anything in from solar or other sources. I think what I have is overkill for my needs. The main thing in my case is that I don't have room on the roof for much solar. I've got a single 320watt panel right now. I might be able to squeeze another 200 watts somewhere else on the roof. The nice thing about this setup is that I can go a week or so in the shade if I'm not using the AC and am limiting my microwave use. Or more importantly, I can run the air conditioner on the drive home from just about anyplace I go.

SomeDay · 06-10-2022, 03:52 PM

When our rig was 11 years old our Nevercold fridge freezer died a death and the cost to replace or repair (all other components would still be 11 years old so....), we decided to replace with a domestic regular fridge freezer, update the tube TV to lighter and energy efficient flat screen and still have money in hand towards a solar set up. We decided to put as much solar as the roof would take which is 1000w. Our battery capacity was 880ahs at install now 900ahs. We were advised to run an electric fridge/freezer we should have at least 440ah's usable battery capacity and allowing fact that we use golf cart style ones can only deplete so much to prolong life.

We have never looked back and even use the microwave plus all usual every day plug ins like tech stuff, hair dryers etc just as we would in a SnB. In fact we don't ever hook up or run the generator nowadays when out travelling unless we need to run the A/C for more than an hour.

It's probably over kill but has served us well since 2014 (replaced battery bank, and settings ourselves, last year. After the initial when brand new installers boiled them but with TLC they still lasted us 7 years after the fact).

That's what's worked for us the past 8+ years extended RVing trips 99% boondocking or dry camping.

cruizerEd · 07-03-2022, 06:39 AM

800AH LifeBlue LifePO4 at 12V. Charging with 2KW of solar using three Blue Sky charge controllers or magnum 2800 inverter/charger.

Going with 48V was a smart choice, your inverter will be much more practical.

One thing on my wish list is a 120A charger that I can use when doing generator runs. That way I can balance my loads on the two legs of the generator and cut my runtimes in half. I haven't found a charger I like. I want one that is programmable and has a good remote.

Don't really regret it but I wish I had the time and funds to put the batteries where the old batteries were. This would require a lot of cutting and welding to adjust the space, and add insulation and ventilation. I shoe horned them in to some other wasted space but access is a major PITA.

Marine359 · 07-03-2022, 09:58 AM

IMHO, you only need a battery bank to support the number of days you normally boondock. Our normal boondocking is for 3 days, so we have no plans to upgrade our 170ah LiFEPo4. However, we will be adding 360w of additional solar, because our compressor fridge is the cause of the 3 day limit without using generator. With more solar, we’ll only be limited by the size of our black tank. Gray water can be hauled away in tote, and fresh water replenished with Reliant jugs.