How much battery do you have?

[kb0zke]

We've kind of decided that the space under the front couch can be given to the batteries and maybe also the MultiPlus II. The space under the rear-facing dinette seat is the other possibility for the MP II. There is plenty of room under the couch for as many batteries as I want to put there, so that isn't the point. I can fit four Li Time 560AH batteries there if I wanted to.


My questions are a bit more basic than that:
1) how many amp hours of battery do you have?
2) is that enough?


I'm interested in hearing from people who boondock frequently.


As of this writing, the best deal on batteries that I've found is a set of four Redodo 12V 280AH batteries for $1,920.99. That's less than I paid for the two Redodo 24V 200AH batteries 16 months ago.td p { orphans: 0; widows: 0; background: transparent }p { line-height: 115%; margin-bottom: 0.1in; background: transparent }

[os1r1s]

I have 920AH worth of batteries. I just installed them, so I don't have too much experience boondocking yet. My calculations tell me that as long as the outside temp is < 80F at its peak, I should be able to make at least 7 days avoiding the AC. I will also be able to run one AC for 5-6 hours off of battery power if needed. Of note, the MP2 will support powerassist to augment a lower amperage connection to let you run bigger appliances. And lastly, remember you have to be able to charge them back up in a timely fashion. An MP2 will charge at 120 amps per hour at full tilt. That means you would take 19 hours to replenish the battery. With a double DC-DC charger, it would take 22.4 hours.



I would encourage you to think of one other thing. I will never buy another battery that doesn't expose the BMS in some form or fashion. The ones I use have Bluetooth BMS support, but also support Victron comms. That is incredibly important to me as a feature. Without it, you'll never really know the balance of the cells, or batteries. And your 100% might really only be 80% after a number of cycles.

[Wazbro]

Check this thread.
https://www.airforums.com/forums/f44...nk-231834.html

[LilBird]

This. The Victron Connect app has been a godsend: it lets me see how much power I have under current load so that I’m able to adjust accordingly. That’s really the only feature I regularly use, but it makes an enormous difference.

To answer your specific question, we have 600ah and 8 solar panels. The space under the recliner and under one of the dinette seats are dedicated to power and Alde equipment. With this setup, we’re able to boondock for a week, depending on weather. The previous owners of our trailer outfitted it for boondocking and said they didn’t travel with a generator and had been out for 14 days. Unless we carried water in our truck, we would run out of fresh water well before then. Candidly, my sweet spot is 4 days - a no brainer with our setup.

[ROBERT CROSS]

2- 100a BB.
Honda 2000. LP/petrol.
2-180w Zamp portable panels.

We use them all, good for 12-15 days when naked in the sticks.

Bob
🇺🇸

[field & stream]

Respectfully, it doesn’t matter how many Ah other people have. Without knowing their camping style and the power demands of their trailer, it is just meaningless data.

You need to determine your power demands based on your style, decide how many days you want to be able to camp unplugged, and go from there.

For example, we have a single 100Ah lithium battery and with no solar or generator can camp unplugged for a week to ten days. Those facts don’t help you at all.

[AlbertF]

Everybody's needs are different.

We have a pair of golf cart batteries. Perhaps 120 Ah usable capacity.

Our limiting factor is grey water capacity, which keeps us to a maximum of four nights in one place. Using a mere 40 watt solar panel, we usually pull out with a 60%+ state of charge. I sometimes think about buying a bigger panel or mounting something on the roof, but then I realize there's no need; our current system works very well.

We only use the furnace for an hour on chilly mornings.

If I need to work, I take along a small fully charged 12v battery and inverter to charge the computer. I may switch to a lithium battery - 30 to 40 Ah - for this purpose. When the GC2s need replacing, we will probably upgrade the converter and buy a lithium battery - perhaps 200 Ah. The GC2s were only $100 each (CAD) at Costco in 2022, but prices that low seem to be a thing of the past and lithiums are steadily becoming more affordable.

[BGClassic]

Classic 33, 4x100Ah BB, inside. Victron suite, factory solar, 270W. Can go 4+ days at Harvest Hosts, and in Canadian Provincial Parks. Generac 3000i generator, so I can run AC if needed. Tanks are the limit, so using campground facilities stretches the stay.

I could add better solar panels, and run better cabling, but it's not a priority.

[jeffb831]

The true answer is never enough.

The problem with a large battery bank is how to recharge it in a timely manner. When you get too large, no amount of solar will fit on the roof of the trailer that will recharge the battery during the day. You will then need to rely on a generator to charge the batteries to full during non-daylight hours. If you are going to utilize a generator, you might as well just use the generator to power the AC and other large energy draw appliances.

[JeffKim]

Originally Posted by field & stream

Respectfully, it doesn’t matter how many Ah other people have. Without knowing their camping style and the power demands of their trailer, it is just meaningless data.

You need to determine your power demands based on your style, decide how many days you want to be able to camp unplugged, and go from there.

For example, we have a single 100Ah lithium battery and with no solar or generator can camp unplugged for a week to ten days. Those facts don’t help you at all.

Couldn't agree more. If you want to be anal when I was deciding on batteries I made up a spreadsheet and estimated all our loads (12V frig, lights, computers, furnace, fans, Starlink, etc.) weighed by duty time and took a guess at solar yield. We also wanted to be at least one week without power. The answer was something like 300Ah (I'd have to look*) without running down to zero. So we have 400Ah. I'd say more would be better but it's not an issue. We also don't run A/C on battery which would drastically affect this number, but then I think you have an absorption frig (?).

Also, I'm guessing with advancing battery technology, I will get be able to get 2x what I have now for the same cost (independent of tariffs) in less space when I'm tempted to replace them in a few years. I know you're full timers but I'd look at the cheaper options in batteries. Even if you drain them once a day (unlikely) that's 365 times and most batteries are rated in the 5,000 cycle range to 80% capacity.

*Edit: Less than I thought - it was only two batteries and our 300W Jackery. But four batteries fit and they were pretty cheap.

[LNBright]

Up until now, I've had the stock pair of 75aH lead-acid batteries.
Just now swapped for four 100aH lithiums, tied together w/ copper bars, relocated under the bed.

[StogieMan]

Originally Posted by jeffb831

The true answer is never enough.

The problem with a large battery bank is how to recharge it in a timely manner. When you get too large, no amount of solar will fit on the roof of the trailer that will recharge the battery during the day. You will then need to rely on a generator to charge the batteries to full during non-daylight hours. If you are going to utilize a generator, you might as well just use the generator to power the AC and other large energy draw appliances.

Spot on and +1.

We went from 600 Ah’s to 920 Ah’s and the biggest concern is how to get them charged up. We have a van and we installed two 50A Victron Orion XS’ in parallel to get the batteries charged up while under travel. We also have 400 watts of solar which is all that we could get up on the roof of the van. So while under way on a nice sunny day we have the Orions and solar panels charging. If it’s a crappy day, I’ll turn on the generator for some additional charging along with the Orions. However, to be honest the Orions and solar do the bulk of the work for charging.

If we could fit another 460 Ah battery - we would install it but it just doesn’t fit. Our vans are hot so the bulk of the use is on the AC when parked with no shore power. When traveling, we just turn the generator on to run the AC and that usually balances out. So bottom line IMO - go with as much battery AH’s as you can afford.

[richard5933]

We've got two Battleborn 100a batteries under the front sofa along with all the other equipment. Probably could have squeezed one more under there, maybe two with a shoe horn but then the inverter would have been very difficult to fit in. The limiting factor for us is the steel tube that runs the length of the sofa as well as the pull-out storage drawer which together force everything under the sofa to the rear half of the sofa only.

Is 200a enough capacity? For us, paired with 400w of solar on the roof yes. But we're not trying to run the a/c from the batteries or use the microwave more than a few brief minutes.

We've yet to run into a situation where 200a couldn't easily get us through the night, but if we had a 12vdc fridge it would have been close. If we had one of those I'd probably try and squeeze the third battery under there.

[SallyForth]

As it pertains to lithium batteries: I’ve learned through personal experience that there is a balance between battery capacity and charging capacity that needs to achieved.

Yes, there is utility in a very large battery bank, but over time, if it is rarely fully charged, an imbalance within a battery’s cells and / or between individual batteries in a bank, can be problematic.

For this reason I’ve learned to place more emphasis on battery charging, solar and DC to DC charging in my case, than on battery capacity.

[GettinAway]

(2) 100ah BB lithium batteries. Plus a 200w portable solar panel. (I’m not a big fan of generators). We’ve gone 10 days without a hookup. However,, we seldom camp where we need AC. That would change everything. Our propane furnace gets used 100x more than AC.

[MRA]

If you are worried about running out of juice then battery capacity is the last of 3 places to look in order to solve the problem.
Place #1: reduce usage turn of stuff you are not using.
a) Start with the inverter. Do not use it as it uses massive amounts of power. If you want to charge your devices get 12v chargers. Convert your starlink to 12v. get a 12v supply for your cpap or other medical device. Throw out the hair dryer.
b) tame your fridge.. turn down your electric fridge. Find the lowest temp that works. use the cold zones to your advantage (ie: the back of our fridge is always coldest so that is where the most perishables go; the door is the warmest so that is where things that are less sensitive (catsup, mustard, yogurt, eggs) go. Put the fridge in night mode when you go to bed.
c) be ok with colder temps - that furnace fan is a watt hog. use down duvets at night and wear a wool during the day.
d) turn off everything not currently in use. unplug those televisions turn off the hot water heater turn off the water pump turn off the power awning. all these small vampires add up
We find that we use about 60ah a day doing this.

Place #2 increase generation.
a) a dc-dc charger was the best investment we made i. this regard. because now we never arrive at a new site without a full charge.
b) if this is not enough then add solar to the roof. we had 300watts originally and this replenished all our previous nights usage by about 11:00am assuming it was sunny. Since it is not always sunny we squeezed an addition 200w onto the roof. We could get another 100 up there by rearranging the existing panels, but there has thus far been no real need

place#3 only theen look to increasing battery.
Our batteries? 200ah LifePo. It was the most I could put in the tongue box when I bougt the trailer. There are now other options and many people get 300 or more in that box.
Why is this the last place? because adding more battery only treats the symptom of running out of juice not the cause. The cause is either using too much or not replentishing what you have used.

[3OnOurWay]

MRA, well said for anyone considering changes and investments. A shunt really opens your eyes over usage about usage and where AH are being lost.

[tjdonahoe]

360 watts of zamp solar and 2 gp 27 interstate wet cells no problem with power.

[SuperTrouper]

Hi David, We started with 400Watts of Solar and 220AH of AGM. We upgraded to 300AH of lithium. We recently upgraded to 510W of solar on the roof and 460AH of lithium which is our boondocking sweetspot for an average usage of 80-100AH per day and a 7 day stay. With limited solar (overcast or redwoods) we can go 4-5 days and then add some AH with 3 hours of propane generator. The beauty of lithium lies in it's ability to charge quickly.
Here's a link to a post I made back when I had 400W/300AH that details usage. Note: I only have a 300W inverter so no AC or Microwave. https://www.airforums.com/forums/f38...ml#post2652825

[kb0zke]

Thanks for all of your comments. I'm doing a lot of measuring and drawing lines on paper. That much doesn't cost me anything but some time, and I'm retired, so I have a few extra minutes.


Prices will probably vary some between now and this Fall, so I'm planning for a couple of different routes, depending on who has the best deal when I'm ready to buy. Dylan Morrison, Superstition Solar, will do the installation. He says he is sure he can put 800W on the roof, and maybe 1000W. When we're in JC later this year I'll see if I can get a print of the roof plan. That ought to help Dylan quite a bit.