New Agm Fullriver Dc85 Battery On The Way

The 2017 Everlast factory battery just self-discharged from 12.4V down to 9.9V in a very short time. Re-charged it, and it essentially passed a load test at my mechanics. But I don't trust a 6-yr old battery for a 10-day trip on the Blue Ridge PW next month. A full 6 years of service would be at the max for most non-AGM batteries.

After a lot of searching, and coming up empty on a U.S. Battery AGM24 Deep Cycle (which would have been my top choice), and being unable to track down a Canadian-made Surrette Rolls, I arrived at a Fullriver DC85.
DC85-12 Battery from Fullriver Battery

Because it isn't a hybrid/Marine battery and is a true Deep Cycle battery, it can actually be discharged down to 20%, or below without causing irreversible damage. As opposed to the 50% DOD, or 12.0V that we normally limit ourselves to with the factory flooded lead acid/ Marine/dual-purpose batteries. Granted, a deep, deep discharge such as that won't damage the Fullriver, but it will lower the number of lifetime cycles that it can pull off.

It's specs are respectable: It's an 85 amp hour capacity at the 20/hr discharge rate, and a true Group 24 in size, which will fit the battery compartment.

I was skeptical of the U.S. HQ/Chinese Factory company set-up, but the following video allayed any fears that it's design wasn't robust enough for a trailer:



Other searches confirmed that the company is legit and has a long and decent track record.

It's low cranking amps spec (510) when you can find them even listed, indicate that the plates are thicker, and that this is truly a Deep Cycle/storage battery and isn't designed, intended, or marketed to be able to turn over an engine. It could, in a pinch. But that isn't something any of us need the trailer battery to do anyway.

This manufacturer is typically only sold by solar and renewable energy suppliers, and wouldn't necessarily turn up in a normal search for a trailer/RV battery replacement. Unless you started digging deep. As such, I thought I'd throw it out to you as an option for your short list. U.S. Battery, Trojan and Rolls Deep Cycle AGM batteries would also be comparable to this one, in terms of quality, performance and price, and all of those would be entirely North American-made. Unfortunately, I was limited by what could show up at my door in time. But I don't think this Sino-American product is a compromise.

Steve

 

I'll be excited to hear about your experience. I've deep discharged my batter 3 or 4 times now. It still tests good as well, the load tester I have still says 100%. Considering the battery is almost exactly 2 years old, I'm skeptical as well.

I've been thinking about LIFEPO4 but I'm just still not sold on it -- I intend to keep mine plugged in at all times, because I keep the fridge running, the media server, and the routine parasitic draw of the camper....and these lifepo4's don't deal well with that.

I'm very interested in how this works for you. I'm not sold on LIFEPO4 and am curious how this will compare...

 

I would consider anything less than 8 years of service to be a failure, at this price point, relative to what I just pulled out of the trailer. And that's taking into consideration, and being able to enjoy, the improved charging, discharging and self-discharge characteristics of the AGM, compared to a standard FLA. Closer to 10 years and I'm a Happy Camper. Time will tell.

I should have attached the spec sheets. Here's the links: https://fullriverbattery.b-cdn.net/wp-content/uploads/battery-installation-manual-english.pdf and https://fullriverbattery.b-cdn.net/wp-content/uploads/DC85-12.pdf and https://fullriverbattery.b-cdn.net/wp-content/uploads/charging-instructions-english.pdf

The owner's manual (all English) is 24 pages. Pretty detailed, including temperature-adjusted charging. Which is way beyond what I or any other trailer user wish to, or can practically take advantage of. It's more for those who use them as a stationary power bank in series. Important stuff for C-I owners is that it's 9.3" to the top of the posts and the other dimensions (7" x 11") are exactly what the Everlast is/was. So it will fit. And that the Marinco trailer charger bulk and absorption voltage rates (14.3V) come in at slightly less than the 14.7V recommended by Fullriver. So that's good too.

However, the State of Charge/ Depth of Discharge profile is slightly different (higher): 12.85V at 100% down to just 12.2V at 50%. So I have to change my SOC reference chart. Performing a DOD of 30% (SOC 70% and 12.47V) each time nets you about 2000 life cycles. Which will allow it to more than surpass its life expectancy as a trailer battery. Even near-complete discharges down to 11.75V every time (SOC 20%) nets you about 800 life cycles, which would still exceed most trailer users' life-time demands.

Given these types of capacities, I'm not sure either that LIFEPO4, as you said, is really worth the leap (cost, different charger). I do like the ability of this AGM to tolerate some (many?) inadvertent deep discharges on our parts. Which seems to be the thing that gets most of us in trouble, battery-wise.

 

Great research and review Steve!
Thats a very smart solution imho.

Note IIRC A couple guys have been able to shoehorn in a 100ah victron agm- Seth and Dustin *might* update on their howgozit since?

I'lll bet there are more that might come out in discussions at CICO2023.

Fwiw went with an off the shelf AGM with marine adaptors to connect up the wires to CampInn and NOCO5 shore charger (after I killed those)

I wanted to be able to go to any O'Reilys, AdvanceAuto, Autozone type store in flyover America to replace something I busted or fried by too often deep discharge or otherwise in the middle of a camping trip.

Like you say, on car batteries or trolling motors that are similar, you can only go to 50%, unless you dont mind degrading life of battery some.

Its pretty common for noobs.
I've over discharged a pair of Sears DieHard Platinums over 8 years of use in a tent trailer using it for phones, kids tablet, interior lights, running gas furnace motor, etc
And kept some degraded life;

by "slow repair" type re-charging from battery maintainer and later by solar panels, trickle charging with stored;
and a couple times dropped off at Batteries Plus for over night deep cleaning recharge.

After 8 years on these AGMs
(Made back in the day for Sears by same co that made Odyseas, iirc)
One was at 50%, the other at 80% still hanging in there but for shorter use times...and I sold the old tent trailer as is.

So on my current AGM I look forward to replacing that when I kill it, with one of the tested, installed, couple years of others road testing the Lion heated option now offered by CampInn.

Like you, Seth, Dustin I like the ability to deep discharge to 20% SOC if needed, like when camping with Dometic plugged into DC. Having the battery level monitor now makes it easier to not to that by mistake.

And since you cant buy time I dont mind overpaying a bit for not perfect OTS if it means I am easily back on the road same day with "close enough"
vs waiting for the UPS man to deliver the better battery, say...twice (after UPS hypothetically breaking off a corner on loading dock)...
three weeks later.


I have a funny* story about Batteries Plus along those lines for around campfire.
* my battery noobery related

 

Thanks Kevin.

I was aware of their commendable efforts to squeeze one in. I’m not averse to making mods, or performing minor surgery myself on the C-I, but I wanted the battery to have a little breathing room. And to not have to switch out to a Li charger before the Marinco gives up the ghost, if ever. With a portable Ecoflow Lithium on the side, and 100W solar on top, between all these components, (and with no CPAP demands) I have plenty of capacity and flexibility of use. The calculus of additional effort, and hundreds of $$ difference for an extra 10 or 15 amp hours didn’t quite point in that direction for me. Particularly, if this Fullriver has the ability to go nearly as low in DOD (occasionally, or even as frequently) as a Li.

 

My best test so far was probably at Oshkosh this year. I had the Dometic going continuously, and set at about 32 degrees. I had my 100 watt solar panel deployed, but since I was attending the show, I wasn't always at the campsite to keep it optimally positioned. I think it was about on the 3rd day I noticed that the Dometic was warmer than what I had it set at, yet the battery was still showing about 12.5 volts, so I think what was happening was that when the Dometic compressor kicked on, it would momentarily bring the line voltage down to or below 12.2 V, which is where I set my auto disconnect switch to cut off the battery from the CI load. Once the load was off, with the solar panels help, the battery eventually would recover enough to switch the disconnect back on again at the 12.6 V I have that set at.
Anyway once I figured that out, I got out the sogen, and hooked the Dometic to it for the last two days without anymore issues. I think the sogen got down to about 50% powering the Dometic before I left on day 5 of the show. The Victron continued to power the CI with the fantastic fan, the lights, and about an hour of TV each night with the solar panel connected to keep it above the 12.2 V cut off voltage.

So, FWIW, that's not exactly a test of the Victron, or how it handles DOD beyond 50%, since I was trying to avoid that. It was more of a test of how long I could go without a power hook-up which I was happy with. I do have another 220W panel too, which I didn't deploy, but as long as there was sun once in awhile, I think you could go indefinitely, as long as you didn't use AC then the gen may have to make an appearance.

 

Dustin: Nice anecdotal usage description. Real world testing of your capacities when it doesn't really matter will pay dividends if and when it does. Your experience does highlight one of the wild-cards in the equation (other than weather and shade)... which is the Dometic cut-out voltage settings. Batteries that can routinely go down to 11.5V aren't much good if you rely on an electric fridge, have your Dometic settings set too high for the situation, and you can't keep a week's worth of groceries from spoiling. Which is why you need options and flexibility to keep your power source(s) above the bare operational minimums, as you have done. And the situational awareness to monitor and adjust to different and changeable charging conditions as required. Acquiring and installing all the bits and pieces are one thing; efficiently getting them to play well with each other in the grand scheme of normal travel routines, is another.

The trick, I think, is to find that delicate balance of simplicity and sufficient capacity, such that you are not a slave to maintaining your electrical system, components and appliances, and that you can actually spend time doing what you went out with the trailer to do... which is travel and see and do things. Like Oshkosh.

 

Yeah, I actually didn't rely on the Dometic's cut out feature, since as I've mentioned in other posts, the Dometic has a high or low cut out setting, but even the high one takes place at 11.8 volts, which is well below a 50% DOD on your battery, and if it is of the lead acid type, it is being damaged at that point. That is why I installed an adjustable cut off switch, which I set at 12.2V, between the CI's battery cut off switch, and the fuse box (load center).

I'd rather all of a sudden see that I had no power in the CI, and/or Dometic, and realize the cut off switch had done its job, and protected the CI battery from being damaged from over discharging, than to find out things aren't working and now I have both no power, AND a damaged battery. At least with the former scenario, you can find another source of power, like a gen, or sogen, or solar panel, or hook-up, to get things recharged, up and running, and still have a battery that is in good enough condition to be fully recharged. The Dometic, even with the no power, will keep things cool for hours if kept closed, so that gives you some time before spoilage becomes an issue, to take which ever corrective actions are available.

 

I put a Fullriver battery in the back of the pickup in 2018 for running the DC fridge. No issues so far.

 

Thanks Tom. Good to know. You’re half-way to my 10-yr goal.

Dustin: I rechecked the Dometic CF35 setting and it was at Medium (11.4V and 12.2V), which would be too low for the reasons which you clearly pointed out. And far too low for any battery that one would be putting in the trailer. (Not even sure why Dometic has a further Low cut-out setting beyond that: 10.1V? What use could that possibly be?)

The High setting however, (11.8V and 12.6V) would “only” take this new AGM Deep Cycle down to about 25% SOC. Which is tolerable, though not advisable on a regular or semi-regular basis for my new battery. But death to a typical FLA, as you point out. Easy to see why you put in that separate battery cut-out, independent of the Dometic’s “safety” internals.

Unexplainable Ghost Drains, prolonged natural discharge, or unexpectedly accelerated self-discharge (like I experienced at the end of the Everlast’s life) could all do the same thing: catch you with your electrical pants down, and turn the battery into a 50lb paperweight well before its time. That extra cut-off switch is certainly something to look into. Particularly if one has “invested” considerable $$ in a premium battery. Or absolutely needs that battery to be there for them, all the time.

 

After killing my original CI OEM battery (after 10 years of faithful service), and it's replacement 2 years later, (both of which happened after getting our Dometic CF35) I wanted to do something to try to prevent losing another battery to over discharge, and that is when I found the adjustable automatic disconnect switch. It was pretty inexpensive compared to a battery, so I thought I'd give it a try. https://www.amazon.com/Digital-Low-...b9-a72f-0e14a8962246&pd_rd_i=B07R8C9JW9&psc=1

When I first reported on its installation, there was a comment on it being relatively light duty at 20 amps, which is true, but there really isn't much draw from anything on the 12V circuit, including the Dometic, which normally draws less than 1 amp while running.
The main down side of this unit as I see it, is that it will draw under 0.125 amps of current itself while hooked up, so while it will disconnect other loads, it can't disconnect itself. So you need to use your manual battery disconnect switch when the CI is in storage or not hooked up to another power source to keep the battery charged, or it will continue to discharge the battery over an extended period of time to the point of damaging it too.

 

That particular down-side, if one decides to install an auto-disconnect (which I'm glad you raised) may be another practical reason to employ the services of this convenient gadget that I just posted: Inexpensive Battery Low Voltage Monitor

Presumably you have your set cut-off for your device just slightly below, or very close to the plug-in's 12.0V visual alert level.

 

Actually I played it a little on the safe side, and set it to 12.2 volt cut off, but I think I will probably change it to 12.1 . The monitor sounds like it work would well as long as you are close enough by to see/do something about it when it flashes the alarm light when the battery get down to 12V, but with a traditional lead acid battery the damage has already begun by then, and if you are gone all day before you notice it, it could be a lot more damaged before you do see it.
That's essentially what happened to me. I had the little plug in monitor that CI sells for the galley plug, but being away from camp most of the day at the Oshkosh air show kept me from noticing the discharge level until it was too late. Even with the little draw that the auto disconnect continues to use, if it cuts off at 12.1-12.2 V there should enough left to keep the battery safe until the manual cut off is made, and a power source hooked in to recharge.
I used this chart as a guide to keep the SOC at or above 50%.

View attachment 9893

 

That's the one I had been using too. But the Fullriver's discharge profile (according to their manuals) will be slightly different... by 0.2V upward. (i.e. 50% @ 12.2V. Enough to make a difference in discharge strategy and setting other, safer cut-off limits.

It's greater than average DOD capability, however, means that even going down to 12.0V (30%), once in a while, I'm still relatively safe. Just have to adjust my thinking.

 

Battery was installed yesterday. Good fit, with some modifications. The brass terminals need to come off (easy) cuz with them on, it's 1/8" too tall. With the terminals removed, there still are two female threads you can attach the leads to, making it a very low profile installation. Also had to modify C-I's wood "L" bracket that is on the inside of ply panel battery "door" by taking 1/2" off the top section; the case is 1/2" taller than the OEM.

Seems to play well with the Marinco charger.

Going to give it a test drive on the Blue Ridge this coming week at some non-electrical sites.

 

When we lived 1 hr south of the Blue Ridge Parkway in Hickory NC we used to camp at Julian Price on the Parkway. We enjoyed Craggy Gardens near Asheville also. Scenes from the movie Green Mile we’re filmed at the Cone Mansion near Blowing Rock.

 

Thanks Van and Terri.

Itinerary is still a work in progress so your suggestions are indeed welcome. We will be staying in OBX these coming weekdays and starting the Blue Ridge around Asheville on the weekend, and taking it back north. Will check out Craggy Gardens. Julian Price had already been shortlisted, so your confirmation is very useful. We're trying to stay in National Forest campgrounds throughout, as opposed to any State or National Parks, which I figured would be getting most of the attention from leaf-peepers. At least that's what the nearly full reservation profiles suggested 2 weeks ago. Some of these Nat Forest campgrounds keep a fair percentage of sites as non-reservable and are available on a "First Come, First Served" basis, so hopefully those will pan out for us if we just show up. Standing Indian, Carolina Hemlocks, and Black Mountain were also shortlisted.

 

Bla

Black Mountain is not to be missed. We have stayed at Mama Gerties Campground nearby. The sites at the top of the mountain are magical in the morning when the fog sets in the valleys with only the peaks of the mountains seen. There is a cool Motorcycle Museum in nearby Maggie Valley. Ocracoke is our favorite spot on the Outer Banks. Highly recommend the private ferries from Ocracoke to Southport for the day which once was the home to over 700 people. The Park Service has kept the buildings intact. We were lucky and got to see the movement of the Cape Hatteras Lighthouse 25 yrs ago. This has us thinking of another rode trip to NC!

 

Resurrect this in light of my current battery woes...(get it! I kill me!)

ANy national chain I might find them at?

 

I got mine shipped (free) from a renewable energy solar dealer (non-RV) near Ottawa. But the Fullriver site indicates they have a deep cycle dealer in Elkhart. You can filter for product line and radius on Fullriver's site and maybe come up with something closer to you.

Sorry to hear of your battery pain.

I know you have probably torn everything apart that is electrical 5 ways to Sunday. But is there a ghost drain or a micro-short somehow cutting down your batteries in their teen years? If there was a ghost in the machine, I'd think that by now your extensive upgrades and replacements would have possibly, and unknowingly, exorcised it.