Battery choice

I'm kind of late to this party, but maybe I can ask for some advice.

We're looking at replacing a Diehard group 31 deep cycle battery. It was rated at 1150 CCA and 205 reserve minutes.
Sears no longer makes the Diehard platinum batteries, and ours is now seven years old. I haven't always kept it perfectly tended, so it tends to slowly lose voltage on multi-day trips.

Anyone have a good recommendation for a group 31 deep cycle battery?

Thanks
 
I just saw that PKYS has for sale a Victron "super cycle" battery. This is supposed to be an improved version of an AGM deep cycle battery, which they claim has better constant deep cycle performance, and also is a bit lighter and smaller than normal AGM. They are "on sale" now because they are discontinuing because of proposed 25% tariff on batteries from China. Don't really know anything else about them, other than what PKYS states.

"These AGM Super Cycle batteries are the result of recent battery electrochemistry developments. The paste of the positive plates is less sensitive to softening, even in case of repeated 100% discharge of the battery, and new additives to the electrolyte reduce sulfation in case of deep discharge. Tests have shown that the Super Cycle battery does withstand at least three hundred 100% Depth of Discharge cycles."


https://shop.pkys.com/Victron-Energy-12V100Ah-AGM-Super-Cycle-Battery_p_7017.html
 
Thanks for all the inputs, guys!

I'm no battery expert, but here's what I found this morning:

Victron $294 smaller than battery box, but could be padded out. 100AH, but only 500 CCA at 0 degree F

Rolls $$$ 760 CCA at 0 degree F and 910 CCA at 32 degree F
Discharge rate for 25A is 175 min

Lifeline $259 550 CCA at 0 degree F, and 680 CCA at 32 degree F
Discharge rate for 25A is 149 min

EastPenn $282 800 CCA at 0 degrees F, and 1000 CCA at 32 degree F
Discharge rate for 25A is 210 min. AGM construction

EastPenn / Deka is sold by NAPA down the street, and they've got two in stock.
Swapping the core will be easy. I'm not sure how that works with shipped products.

The Diehard 31M #50131 battery we have now was rated at 1150 CCA, which I'm assuming is for 32F

Thanks for the feedback!


If I'm missing something here, let me know. I probably won't buy until at least tomorrow.
Last time I bought a battery, I took a screwgun to Sears in Yuba City and had to disassemble the settee, and more
to get the 75 lb battery out of the front corner of our 2008 Hawk
 
Litehawk: If you are looking for a deep cycle battery for use in running things off 12 volt, the CCA metric is not at all helpful. The CCA is only relevant for a starting battery, telling you how many amps it can put out in a short period to start the engine. For a deep cycle battery used in a camper, you should look only at the Amp Hours (AH) rating, and any special aspects such as how many times is can be discharged without damage. There may be a trade off in designing batteries between maximizing CCA and maximizing AH and times it can be discharged. So I think a high CCA rating might actually be a bad sign for a proposed deep cycle battery for use in running 12 volt items in a camper or whatever.
 
Zirdu said:
Litehawk: If you are looking for a deep cycle battery for use in running things off 12 volt, the CCA metric is not at all helpful. The CCA is only relevant for a starting battery, telling you how many amps it can put out in a short period to start the engine. For a deep cycle battery used in a camper, you should look only at the Amp Hours (AH) rating, and any special aspects such as how many times is can be discharged without damage. There may be a trade off in designing batteries between maximizing CCA and maximizing AH and times it can be discharged. So I think a high CCA rating might actually be a bad sign for a proposed deep cycle battery for use in running 12 volt items in a camper or whatever.
Click to expand...
+1 CCA is totally irrelevant in a deep discharge battery
 
Lighthawk said:
Thanks for all the inputs, guys!

I'm no battery expert, but here's what I found this morning:

Victron $294 smaller than battery box, but could be padded out. 100AH, but only 500 CCA at 0 degree F

Rolls $$$ 760 CCA at 0 degree F and 910 CCA at 32 degree F
Discharge rate for 25A is 175 min

Lifeline $259 550 CCA at 0 degree F, and 680 CCA at 32 degree F
Discharge rate for 25A is 149 min

EastPenn $282 800 CCA at 0 degrees F, and 1000 CCA at 32 degree F
Discharge rate for 25A is 210 min. AGM construction

EastPenn / Deka is sold by NAPA down the street, and they've got two in stock.
Swapping the core will be easy. I'm not sure how that works with shipped products.

The Diehard 31M #50131 battery we have now was rated at 1150 CCA, which I'm assuming is for 32F

Thanks for the feedback!


If I'm missing something here, let me know. I probably won't buy until at least tomorrow.
Last time I bought a battery, I took a screwgun to Sears in Yuba City and had to disassemble the settee, and more
to get the 75 lb battery out of the front corner of our 2008 Hawk
Click to expand...
That EastPenn looks like a winner... based on the long run time at 25A. However, I rarely see that deep a discharge rate in my camper. My load is usually 5-10A, if everything is on. Compare the runtime at that load if that's normal in your camper too.
 
Great info in this thread. I've been researching batteries as my 2014 Hawk may need one soon.

I've been reading about AGM vs gel batteries. Seems that gel batteries are a great choice as all the data I've seen indicate that gel batteries can tolerate almost twice the number of deep discharge cycles.

As an example, using data from the Renogy website: https://www.renogy.com/products/deep-cycle-batteries/ their 100Ah AGM battery can tolerate 600 cycles to 50% discharge, while the 100Ah gel battery can tolerate 1100 cycles. In addition, gel batteries lose less capacity per month as they age.

However, it seems that gel batteries need a specific charge profile or they can be damaged. Can anyone provide more info on this topic? Specifically, can we use gel batteries in our campers?
 
Been following this topic and am replacing an Exide Dual that was in my Eagle with a true AGM battery (probably a VMAX). My question is regarding amp hours. I'll be running the Dometic 3 way and also the included 4WC propane heater during the Winter. I'm planning on adding a 200 watt solar system as well. The question is how much battery capacity I should shoot for and if I should purchase higher capacity (Amp Hour) battery or purchase 2 batteries and run in parallel. Looking at the MR137-120 (120 amp hours) for $299 or the XTR12-155 (155 amp hours) for $389. Appreciate any feedback!
 
Mthomas said:
Another idea: LiFePO4.
Click to expand...
LiFePO4 is a great (and expensive) solution unless you spend time in below freezing temperatures. You either need enough capacity to power your camper until you can get them somewhere where they can warm up and be recharged or you need to keep them warm.
 
The issue with charging LiFePO4 (or really any lithium battery) below freezing is definitely something to be aware of, but is not a show stopper. I have an LiFePO4 battery, and probably camp more at or below freezing than during the summer. If the batteries are inside your living space, it is not really an issue as when you are using the camper, the batteries are warm enough to charge.

The biggest issue is charging from solar when your camper is parked and it is cold, but luckily the Victron MPPT charge controllers have an adjustable low temperature cut off for just this reason, as do most BMS.
 
camsf said:
Been following this topic and am replacing an Exide Dual that was in my Eagle with a true AGM battery (probably a VMAX). My question is regarding amp hours. I'll be running the Dometic 3 way and also the included 4WC propane heater during the Winter. I'm planning on adding a 200 watt solar system as well. The question is how much battery capacity I should shoot for and if I should purchase higher capacity (Amp Hour) battery or purchase 2 batteries and run in parallel. Looking at the MR137-120 (120 amp hours) for $299 or the XTR12-155 (155 amp hours) for $389. Appreciate any feedback!
Click to expand...
You need to total up your AH drawn in a day. I assume you will be running the 3 way on propane when parked? Because if that is true, then you are just looking at the heater blower plus your lights and charging phones/laptops, right? A guess here would be about 10A of draw for about 40% of a day, so about 7 hours a day = 7*10 = 70AH. Better than guessing would be to install a shunt based battery monitor like the Victron BMV 712, so you can measure the AH used.

Going with our guess of 70AH, you would want at least a 150AH battery so you can stay one day in one place without charging. I sized my battery bank for 3 days without charging. I used two 6v batteries because a single 250AH battery weighed too much for me to lift it into place!

Oh, and I think instead of looking for "a true AGM battery" you might want to look for "a true DEEP CYCLE battery", not a dual purpose battery. DEEP CYCLE batteries can be AGM or Flooded or LiFePo.
 
Vic thanks for the explanation. Yep, deep cycle and am focusing on AGM. Thanks for the AH estimate. Just based on that I'm thinking of going your way with 2 batteries as I'd rather be able to run during the Winter for a couple of days without draining power, assuming clouds/snow reducing solar charge ability.
 
You can never be sure what the weather will do. I'd hate to be stuck inside and run out of power. Only real downside of oversizing your system is weight. Plenty of people want/need more power but you never hear anyone complaining about having too much power!

Another thing to consider is future use. Right now I'm not inside the camper much except for sleeping but expect that will change when I retire and I'm spending weeks on the road instead of days.
 
You must log in or register to reply here.

Similar threads - WTW

K7MDL
Installed Renogy One Core monitor and Battery Shunt 300
K7MDL
K7MDL
craig333
Made the switch to LiFePO4
craig333
craig333
Z
2006 FWC Electrical Issue
Wandering Sagebrush
Wandering Sagebrush
W
Q for this still running their old Atwood heaters
Saturn949
S
R
Rear solar SAE port
Deancamp
D

New posts - WTW

Back
Top Bottom