Camper Batteries - Advice?
ZHP Sparky - the 5th last edited by ZHP Sparky - the 5th
The 35AH Optima red top that came with our little camper is DEAD dead. Lights were dimming at the end of our maiden camping trip this fall, and soon after getting home it had zero juice left. I tried my multimeter on it and it showed a big fat zero. Of course "smart" battery charger doesn't recognize it as a battery at this point. Thanks, Pal!
Might try some hacks to get some juice in it and see if I can get it to charge, but also of a mind to get a new battery as I'm pretty sure the thing is original to the trailer (a la 2013). Our trailer is just a small 1300lb thing with a galley in the back and small sleeping section. All we'd power with it are a few overhead lights (got LED replacement bulbs which should help a lot) and maybe a 12v heating blanket if absolutely needed - I know that draws a lot, but we also have a Jackery power box for that if needed. Charge phones, that's the most I can imagine.
Questions - any advice on a replacement battery and capacity? My current thinking -
Don't want to deal with a battery that needs topping off, so leaning AGM. Lithium seems way too expensive for our use case. It would be nice to have the discharge depth of a Lithium, but will have to settle for the 50% or so on an AGM.
Given how old/abused our current battery was I don't really know how reflective that battery is of a true 35AH unit. Does that capacity seem sufficient for our use for say 2-3 night trips? With a couple of LEDs drawing 2-4W a piece seems like it should be?
Don't want anything much heavier than our current battery so hoping to stick to something under 50lbs (tongue weight, especially on a Subaru only rated for 220lbs)
Any input on what you folks have in your campers or similar use cases? Best options as far as combination between price/capacity/weight/maintenance? I'm thinking of just buying a 50-75AH AGM for around $100-150 and calling it a day.
jminer last edited by
My experience from running AGM batteries on old motorcycles with meh charging systems is be careful if you think you'll drain it completely (like with this one). They're far less tolerant of abuse than the lead acid batteries and far less likely to be saveable if drained completely. Something like a deep cycle lead acid battery is probably your best bet both for capacity and durability. Something designed for use in a boat to run a trolling motor would be perfect.
That also being said you might want to put a solar trickle charger on it to help keep it alive longer.
ITA97 last edited by
Like jminer, I've also seen the habit for AGM batteries to be good, but not tolerant of being drawn down too far. If you had to pick an AGM, I'd probably go with an Optima Blue top Marine/deep cycle battery. In general, you'll probably be better off picking an deep cycle battery, as those are designed to power steady loads to deep discharge states and live to tell about it. A red top is a starting battery. In this case, I'd go to your local Interstate dealer and pickup the appropriately sized conventional marine deep cycle battery.
VincentMalamute last edited by VincentMalamute
Your 35 AH battery for two LEDs (1AH total) and a few other sundries is more than sufficient for several days. You know about the 50% depth of discharge limit for battery life so you must know you need a deep discharge battery. I think an AGM deep discharge is fine as is your idea of upgrading to a 50-75Ah battery.
What kind of charging system do you have? Like @jminer says, some kind of battery maintainer may keep your battery alive longer. But 7 years is a reasonable life span.
If you're looking for quality and price, Walmart is good. There's only like 3 or 4 battery manufacturers that supply most of the market and one of them (I think Johnson Controls?) makes the Walmart batteries. They usually test well according to Consumer Reports.
nermal last edited by
@zhp-sparky-the-5th Remember that the RV industry is populated by employees that have been fired from shady cell phone stores (sales), the post office (customer service), and FCA plants for being too drunk / high / stupid (manufacturing). It's sole reason for existing is to take advantage of old people.
Looking at things from that perspective, make sure you go over the rest of the wiring on the camper. It may be the battery, it may be shitty wiring, it may be a combo of the two.
I speak from experience here, as I replaced the battery on my toy hauler earlier this year when it stopped being able to power the water pump and a light at the same time. Turns out it wasn't the battery, as the new one did the same thing. Ended up being a bad wire that had an exposed connection that was rusted as shit.
Otherwise just get one of the cheap deep cycle ones from the auto parts stores. They are specifically marked as RV / Marine. The replacement that I got was around $100. It's good for lights and water, haven't tried to run the furnace off it yet though.
frinesi2 last edited by frinesi2
The nice thing about lithium is, you can unhook it and let it sit for years and it will still have a full charge.
SilentbutnotreallyDeadly last edited by
we run a 100ah AGM battery from Delkor. It does the job but it doesn't like going below 50% at all - if it does it takes an age to recharge and only then if it hasn't been damaged. Ours is designed for a constant use situation in an RV so it needs to be hooked up to an energy source (either the car or solar) at all possible times. Which is a bit of a pain in the arse.
The other option is to use it in conjunction with a low voltage cutout so it doesn't get overly discharged. Which is additional cost, complexity and a pain in the arse. Primarily because we run a 40 litre Engel fridge when we camp...
Next time, I will be sourcing an AGM deep cycle battery...I suggest you do the same as a minimum.
LooseonExit last edited by LooseonExit
AGMs are terrible with questionable charge systems or when you draw them down far like @jminer and @ITA97 mentioned. My Buell 1125CR ate an AGM battery every year, but the stator system was barely enough to cover charging needs so by the end of the year it'd be dead. I ran a tiny Deka AGM (believe is was 8-10lbs, little guy) in my LS1 Camaro but it made a lot of juice so it was fine. A deep cycle (AGM or otherwise) or lithium is what I'd do.
drVanTraveler last edited by
Anyone who is considering lithium batteries, make sure you understand their cold weather problems. AGM's at least can handle cold.
ZHP Sparky - the 5th last edited by ZHP Sparky - the 5th
@jminer @ITA97 @drVanTraveler @LooseonExit @SilentbutnotreallyDeadly @frinesi2 @nermal Thanks to you all for your responses - sorry I posted my request towards the end of the workday, got distracted with last minute deadlines, and lost track of this for the rest of the evening.
Yes absolutely the replacement I'm looking at will be a deep cycle battery - and am aware the red top is marketed as a cranking battery...but I've also read that there is very little actual difference between the redtops and blue/yellows other than the terminals on them, but who knows what to believe you read on the internet. As most of you have suggested a deep cycle AGM/SLA is what I'm tending towards.
A gel or lithium doesn't seem worth it to me for a variety of reasons (cost, finicky charging requirements for gel, etc.) - and outside of an actual power loss issue on my trailer itself something around the 35-50aH should be plenty for my use, maybe something a bit bigger if I want that extra capacity to protect against potential over-discharge.
I do have a small 60W solar panel for our Jackery which I do intend to rig up a charge controller and wiring to be able to keep the battery getting some charge while at the campsite. Definitely learnt my lesson on plugging in the trickle charger as soon as I get home too. Unfortunately we only have a 4pin connection on the trailer wiring to our car for the lights, so no automatic charging
from the car battery/alternator on the way back home just to ensure I don't leave it completely drained and forget about it.
All the different types and names for batteries makes my head hurt, thanks for the input!
ZHP Sparky - the 5th last edited by
@frinesi2 Yeah unfortunately they are crazy expensive and not worth the investment for my limited use. Have seen some cool videos online about making a LiPo battery bank of your own which seems to be a cheap way to get in to lithium. But again probably not worth it at this point for our use.