Battery life

Bigcountryman69 · 04-22-2018, 04:10 AM

Hi all, new to the forum and first time post... we have a sprinter 318fls. by day our portable generator keeps things going. usually i shut it down about 9pm ... but my batteries (2 linked together) wont last the night for our heat.... any suggestions?

**JRTJH** · 04-22-2018, 04:29 AM

You don't say what size or type of batteries you currently have. If they are "standard GP24 deep cycle" batteries, they probably are being "outclassed" by the demand for power during the evening.

Some would suggest upgrading to GP27 or even GP31 (12 Volt batteries) while others would suggest upgrading to a 6 volt (golf cart batteries) system. Whatever you do, be sure that you're getting "true" deep cycle batteries, not the "typical "dual use" battery.

For most of us, a dual 6 volt battery system is sufficient for "conservative dry camping" for 3 or 4 days without furnace use or for overnights with extensive furnace use. Augmenting that with a generator or a solar recharging system will usually provide enough power for most lifestyles. But if you or someone in the camper "needs the TV running for noise" no matter what they're doing, it's hard to power that kind of lifestyle when dry camping.

ChuckS · 04-22-2018, 06:09 AM

You will most likely find you will never have enough battery amperage to last thru the night with two group 24 batteries running the RV furnace... you have to also consider the fridge, CO2 detector, possibly stereo if installed, etc are all consum8ng DC power..

We experienced the same issue with two group 24 batteries being just about dead every morning when boon docking and having to run furnace at a setting of 58 at night to keep fifth wheel reasonably comfortable.

Solution for us was two Costco GC2 golf cart batteries wired in series.. cost per battery was about $80 plus I upgraded battery to battery interconnect cable to heavier gauge..

We now dry camp and in the morning our batteries read 3/4 full and when tested with hydrometer the specific gravity verifies the idiot light panel reading.

Depending on space available for your batteries I’d at least upsize to Grp 27 or larger for 12 volt batteries.. and if you have the space and weight capacity then it’s hard to beat the larger battery plate performer of a golf cart battery.. And yes, the6 are heavier due to muc( larger plate surface

**chuckster57** · 04-22-2018, 07:02 AM

I didn't see it mentioned, so I will: how the trailer leads are hooked up will be a big factor. If the trailer leads are connected to one battery, then your drawing from the primary battery and not much from the second one. We connect the batteries in paralell and then connect the trailer leads to OPPOSITE batteries, that way you are drawing off the whole bank and not just one.

Canonman · 04-22-2018, 07:08 AM

I would suggest having the batteries tested. They could just be "tired". You don't say how old the batteries are, but they do have a limited lifespan. Our two group 24 batteries are on their third season and we find they are holding up well even on cold nights when we run the furnace enough to keep our Cougar at about 58.
Any auto parts store can test your batteries and let you know if they have fallen below their optimum operating capacity. I can tell you when we change ours, we'll upgrade to the group 27 size battery.
Power use/consumption is key issue but testing the batteries will let you know if you need to conserve more than you already are.

**JRTJH** · 04-22-2018, 07:19 AM

All deep cycle batteries should not be discharged below about 50%. If your batteries are "dead" every morning after not being able to run the furnace all night, you're probably repeatedly discharging them beyond that 50% recommendation, shortening their life even faster.

Sort of "between a rock and a hard place" with the current batteries. So, it's not "IF" but "WHEN" you upgrade, be sure to consider larger batteries that you won't subject to discharging below 50% with typical use.

GHen · 04-22-2018, 06:52 PM

I also have 2 group 24 batteries, 6 months old.they keep the heat on all night but get down to 12.4v. The generator brings them up pretty quickly in the morning and a 100w solar panel keeps them topped off on most days. So here is the question, if I want to add a couple more batteries, can I add 2 6 volts or a couple group 27’s to the 2 24’s? I believe I read that they should all be the same type. If that’s the case I might just add a couple more 24’s and upgrade all 4 in a few years. Suggestions?

ctbruce · 04-23-2018, 02:46 AM

Quote:

Originally Posted by GHen

I also have 2 group 24 batteries, 6 months old.they keep the heat on all night but get down to 12.4v. The generator brings them up pretty quickly in the morning and a 100w solar panel keeps them topped off on most days. So here is the question, if I want to add a couple more batteries, can I add 2 6 volts or a couple group 27’s to the 2 24’s? I believe I read that they should all be the same type. If that’s the case I might just add a couple more 24’s and upgrade all 4 in a few years. Suggestions?

In general, they should be the same type and the same age. 6 months may be close enough, someone else would have to chime in on that. The older batteries will drag the newer ones down and allow them to charge properly.

bill-e · 04-23-2018, 05:02 AM

Quote:

Originally Posted by JRTJH

All deep cycle batteries should not be discharged below about 50%. I

All "real" deep cycle batteries shouldn't be discharged more than 50%. It's likely the GRP 24's are the hybrid deep cycle/cranking/marine batteries which should not go below 80%.

I "think" I read somewhere that the golf cart batteries held up the best for "deep" discharge but I could be imagining that

cmerkert · 04-26-2018, 10:00 AM

Looking to upgrade to Trojan T105 6v batteries for dry camping on the beach. Tired of my 2 12v needing a charge every day. My question is, is there a size (footprint) difference between the T105 6v and the standard 12v batteries. My batteries in my Cougar XLite are behind the propane inside the nose cone and I am curions if I need to make any modifications, specifically:

1. to the battery tray (footprint size)
2. How much taller are they? Since they in inside the nose cone, there is a top clearnance I need them to fit under.
3. Battery box size (again, same as #2 and I am thinking 6v's are definitely taller)

Would love to hear from others who have T105's or can send me their measurements and if they needed another battery box.

**sourdough** · 04-26-2018, 10:37 AM

Quote:

Originally Posted by cmerkert

Looking to upgrade to Trojan T105 6v batteries for dry camping on the beach. Tired of my 2 12v needing a charge every day. My question is, is there a size (footprint) difference between the T105 6v and the standard 12v batteries. My batteries in my Cougar XLite are behind the propane inside the nose cone and I am curions if I need to make any modifications, specifically:

1. to the battery tray (footprint size)
2. How much taller are they? Since they in inside the nose cone, there is a top clearnance I need them to fit under.
3. Battery box size (again, same as #2 and I am thinking 6v's are definitely taller)

Would love to hear from others who have T105's or can send me their measurements and if they needed another battery box.

My TT has the enclosed nose cone as well. A long time ago I thought of getting 6v batteries but my battery tray is built between the frame rails and the front lip is exactly the width of 2 grp. 24 batteries and the back lip is exactly the depth of the 24s. The measurements for a 6v would not work and I too was worried about the height. Did not get that far because I wasn't willing to cut out all the brackets and re weld new ones for 6v when we don't even dry camp...

bill-e · 04-26-2018, 10:42 AM

Footprint is the same, height is not. I do still use the 12v box, the cover just doesn't fit well.

Amazon.com battery box

T-105 specs

bill-e · 04-26-2018, 10:58 AM

Quote:

Originally Posted by cmerkert

L My batteries in my Cougar XLite are behind the propane inside the nose cone

Do you really mean inside or just recessed into the nose. My nose is recessed to fit the batteries and yes, the T-105's fit. It would be easier to get the batteries in and out if they were forward a few inches and maybe someday I'll have new brackets welded but the OEM placement works for me.

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