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Topic: Battery time (Read 859 times) previous topic - next topic

Battery time

So my 3 8 year old Agm battery's are heading west, one is already done. Couple of questions, and I'm still using the original inverter/ charger. 1350 watts of solar with Outback 150/80 controller, separate 1000watt inverter that takes care of tv, and such. Residual fridge may be in the future. Although we may or may not be full time 2or3 more years.
Anyone with a residual fridge using 3 agm batteries with say 350Ah useable? Will they take care of electrical needs overnight, along the tv and other minor loads.  Least costly route for new batteries. We do boondock 6/7 mos  out of the year and we are time.

Or 600Ah of lithium( 2 300ah) Which will of course require a stand alone charger, heat pads, Victron shunt, and learning curve, just to get started.

Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: Battery time

Reply #1 –
Bruce, I reached the same crossroad a few years back. My 6 year old Lifeline AGM's were getting to the end of their life. We have a residential refrigerator and Lynda watches a lot of DTV. The solar had the batteries fully charged by dark and I would run the generator 1/2 hour before curfew at parks. I could still make it through the night and make Lynda coffee. If I wanted to use the toaster or the microwave the generator was needed during their use. Then the solar brought them back up. The O'Reiley AGM's were in my crosshairs when Amazon started selling the 200 amp D size batteries for $799. Roger had paid $6,000. for his 600 amps of lithium and I could have the same for $2,400. subtracting the cost of new O'Reiley's tipped the scales to go lithium. The price has come down for the batteries I bought but I had to make a choice back then. There is no comparison on the performance between the AGM's and the lithium's. We don't use the generator at all on days of sunshine and after coffee and english muffins with the toaster we are just below 50% SOS in the morning. I did already have the Xantrex sw3012 I don't have heat pads as with an Aqua Hot the batteries never get below 50 deg. even with the ambient in the teens. The B2B charger is only to protect the alternator nothing to do with the batteries. I probably could get along without it but didn't try,.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Battery time

Reply #2 –
I am about there too. My 1996 U295 is set up for (2) 8 batteries I am thinking of going with the Li Time 400ah battery so I will have 800 total with the two. What b2b charger did you use and where did you locate it?
Brian & Lisa Freeze
1996 U295 36FT Build #4914
Motorcade #18760

Re: Battery time

Reply #3 –
If I were to do my setup again, I'd go with Eg4 lithium batteries. There is another member that has these in the battery bay. They're reasonably priced and have excellent reviews. Two of these for less than $3k and you have 800ah of lithium for the next 20 years.

EG4-LifePower4 Lithium Battery | 12V 400AH | Server Rack Battery - Signature...
1999 U320 WTFE #5586
2014 Subaru Forester 6sp
4000 watts of solar
650 aH @ 24v

Re: Battery time

Reply #4 –
You just need to keep the coach in above freezing temps, after the new battery install.
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Lynn & Marilyn Sickel
Tollville, AR
1997  U320  40'
2021 Chevrolet Silverado pickup
Motorcader  17257

Re: Battery time

Reply #5 –
Quote from: Forewheelers –
You just need to keep the coach in above freezing temps, after the new battery install.
Actually as long as you don't charge below freezing you can still have power from the batteries.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Battery time

Reply #6 –
You can install the Orion B2B in place of the isolator, wherever that is, or at foot of bed in the electrical area. The 30 amp will protect your alternator and help top off batteries on a cloudy day running down the road, but most days the big solar bank will do the job. Our residential fridge (10.1 with auto defrost and no ice maker) uses on average 72 amps per day.  I can send you a drawing Roger worked up for me to connect B2B when you are ready. As a full timer you won't see batteries below 5C unless several days in low 20s and teens. You will want a pure sine wave inverter for fridge. Your current battery charger may have a setting that will work. LiTime puts their manual online and lists charging specifications.
1998 36 foot U270 Build No. 5328 WTFE, 900 watts solar, Victron controller, B2B, bat monitor, 600 AMPH lithium with 2018 Chevy Colorado toad, SKP #110239, Motorcade #17781, 2021 Escape 17B for when Coach is broken down and campsites are too small, retired and full-timer since Dec. 2020. Part of RV family since 1963.

Re: Battery time

Reply #7 –
I have 360AH of  LFP( or Lithium iron Phosphate)  batts.    These are take outs from the EV race team. 
    $450 per pack  for 185AH .    Busbarred and ready to install . Seems to work fine and should last years .

Re: Battery time

Reply #8 –
My Samsung uses 120-180Ah per day for the residential fridge when no sun/gen.  Ice maker uses more juice. 
Plan accordingly.
2001 4010 U320 build #5865 "Bluto-d-Bus" since 09/18
2006 Honda Element ESP Toad
Full timing since 2016 in Western MT
Copilot: Sitka
1975 GMC 260 Avion: sold

Re: Battery time

Reply #9 –
There's really no comparison between AGM batteries and lithium iron other than the fact that they both store electrical energy. I would be hesitant to go anywhere with batteries that are failing.
One of the reasons I purchased this particular coach was a previous owner had taken it to AM solar and had a massive amount of work done. Over 15K. This included a whole victron system complete with two 300 amp hour lithium batteries that at the time cost about $4,000 each, as well as the inverter charger the solar mppt controller as well as 1400 watts of solar on the roof. I'm in a all electric coach so no propane. In the winter in Arizona I would have to run the generator once in awhile for about an hour or so but since early February I've been pretty much 100% solar. I use a lot of power. I don't have a residential fridge but a Marine fridge with a bd50 12 volt/120 volt compressor. Last night I went to sleep and my state of charge was around 80% and when I woke up this morning with the inverter off all night it was 72%. I try to cycle my batteries between 90% and 40% but I can go all the way down if I needed to. The other day I cooked in the convection oven for about 45 minutes all on solar. In the morning I still had more than 40% stated charge. I could have started the generator, but chose not to and by 2:00 p.m. the next day I was at 100% again.
Needless to say I could not have done that on AGM batteries well if at all. Lithium batteries have come  down in price significantly so you can do your research and find them fairly inexpensive. Look on YouTube there's always someone testing the newest release from China. You're going to have to buy Chinese lithium. Anything made in the US or Europe will be significantly more expensive. 600 amp hours of lithium is pretty sweet but 800 would be better. Depending on how much you boondock. Of course you have to back it up with an appropriate charger as well as solar. I think for Coach like mine 1400 Watts on the roof is probably the lowest I'd want to go. With the panels out there now at 400 plus Watts each you can do a pretty nice setup for not a lot of money. My batteries are inside where the splendid washer used to be. They use a external BMS. The newer batteries have internal bms's but I like the idea of the external because if it fails I don't have to replace the batteries.
Most of the newer batteries have internal. Research carefully and decide what will work for you better.
As Chuck said, you can use lithium batteries when it's very cold out you just don't want to charge them when they're cold. And if you use them they will warm up especially with a larger load. The BMS will prevent them from being charged if they are too cold.
Lithiums are no longer experimental. They are mainstream even though foretravel will not use them in the coaches yet. I scratched my head when they told me that at the factory. But they are a business and I guess they've been using gel and AGM for a while and for most people that go from RV park to RV park they are more than sufficient.
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired

Re: Battery time

Reply #10 –
Trying to figure out how to keep the batteries at a level below full charge, and still have AC power for the frig and the mini split, thought was of another power source back feeding into the breaker box and shutting the main breaker out of the multiplus, just not sure how to do that, and still have a safe system
1999 36 ft U270
Build 5465

Re: Battery time

Reply #11 –
Why worry about keeping the batteries below full charge? Storage is the only time that is recommended, while in use that is not an issue.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Battery time

Reply #12 –
The manufacturer indicated that they don't like to be kept at full charge so I have been trying to figure out how to keep them below that when I am not using the coach.
1999 36 ft U270
Build 5465

Re: Battery time

Reply #13 –
Is the coach on ac power? you can turn the charge function off on the charger inverter.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Battery time

Reply #14 –
Thanks craneman I will look into shutting off the charger, that would be the easiest thing to do
1999 36 ft U270
Build 5465
 

Re: Battery time

Reply #15 –
Be aware that on some charger/inverters that if power is interrupted they default to charge on when power comes back on. That's how my Xantrex 458 works at least. The only time I would worry about that would be in very cold weather and if you have lithium batteries with a BMS that doesn't have cold charge protection.
1998 36 foot U270 Build No. 5328 WTFE, 900 watts solar, Victron controller, B2B, bat monitor, 600 AMPH lithium with 2018 Chevy Colorado toad, SKP #110239, Motorcade #17781, 2021 Escape 17B for when Coach is broken down and campsites are too small, retired and full-timer since Dec. 2020. Part of RV family since 1963.