Battery Purchase

[TomG2]

My four month old camper came with a dual purpose marine battery and I want to increase my electrical capacity. I realize that dual purpose is not the best choice, but should I pair it with a true deep cycle or purchase a matching dual purpose? I am not ready to throw away a four month old battery just to get two six volt models as I don't boondock that much. Thanks.

[NinerBikes]

pianotuna wrote:
Hi,

Unvented heaters should not be used. If you must be cheap then at least do not use them while sleeping.

Goose down comforter for that.

[pianotuna]

Hi,

Unvented heaters should not be used. If you must be cheap then at least do not use them while sleeping.

[pnichols]

We drycamp a lot with only two 12 volt batteries. During the night we use the furnace a lot, too, plus a CPAP machine - all from just these two 12 volt batteries. About every other day we recharge them from the engine alternator for a little while and then continue with a generator feeding the stock RV converter ganged up with a regular Sears cheap car battery charger.

I agree with most posts above ... all the OP needs is another identical 12V battery to get by ... for probably quite some time yet before spending more money.

By the way, multiple 12 volt RV batteries should be hooked together in a balanced way, as pianotuna mentioned earlier. However, this is a lot of work to make happen when using three 12 volt batteries ... but simple to do using only two 12 volt batteries, as pianotuna showed with his diagram.

[NinerBikes]

TomG2 wrote:
Lights aren't the problem. On a cool/cold night, the furnace will take the current battery below 50%.

Get a Camco Olympic wave 3,6, or 8 catalytic heater instead. Crack a window and a vent, battery problem solved.

Also, change out all your lights to LED lights. Do a search here on good pricing for 48 SMD LED Warm White light panels on Ebay for a good price, and go that route. Smart money spent on LED's, it will solve a lot of battery problems.

[64thunderbolt]

Get another equal batt and run them till they are gone. I boondocked for many yrs with 2 grp 27's Last pair lasted over 7 years. I then went to 2 GC2's. no need to spend the extra money now. Just need a good charge with a charger before leaving and be a little conservative with use and you will be fine. I know there is a science to this but some hair splitting is not necessary to having a fun camping trip. Good luck.

[RAS43]

grizzzman wrote:

TomG2 wrote:
My four month old camper came with a dual purpose marine battery and I want to increase my electrical capacity. I realize that dual purpose is not the best choice, but should I pair it with a true deep cycle or purchase a matching dual purpose? I am not ready to throw away a four month old battery just to get two six volt models as I don't boondock that much. Thanks.

I would suggest getting another similar battery and i would get the most capacity you can afford while your at it. Good luck with it!

X2 Since he does very little boondocking and has a generator this is the least expensive and easiest plan. No sense getting all carried away as some have suggested.

[TomG2]

Thank to all for their opinions and suggestions. I manage my life so that it is spent as close to 75 degrees as possible, and most often stay in campgrounds with hookups. However, sometimes I have to travel for a few nights in cool weather and dry camp along the way. That is why I need a little more reserve in the old battery bank. I have no idea why the dealer installed a dual purpose battery, as he never has before. He is over a thousand miles away, so I won't be running to him for a replacement. I don't mind spending $100-$200 for an upgrade but I am not interested in spending much more for full blown solar setup.

[MEXICOWANDERER]

The gentleman does not sound like he intends to become a grizzled boondocker. As such adding 2 more Costco or Wal-Mart RV batteries is smart, tight, money spent. 150 useable amp hours affords a comfortable margin and they will suck up all the energy produced by a generator and charger. No 70 amp charger and 30 amps going into the battery
In time limited off grid excursions it's hard to beat a battery bank that consumes 100% of a generaror's production.

[dclark1946]

Not sure how much your furnace is running at night but if it is running very much that of course is a significant load. What are your objectives? Do you want to go more than a day between charging? You did not give the battery group size so not sure if you even have a gr 27.

We manage nicely with a single Trojan SCS 200 (Gr 27 115 AH 12V) battery dry camping for over a week in the Smokies during chilly fall weather. We do daily morning charges and run the furnace in the evening and in the morning. It is too noisy to run while sleeping. We use a catalytic heater if it is going to be below 50.

Regardless of what battery you have you need to be sure it is in good condition and can hold 12.6 V for at least 24 hours after a full charge and no load.

Dick

[wa8yxm]

TomG2 wrote:
My four month old camper came with a dual purpose marine battery and I want to increase my electrical capacity. I realize that dual purpose is not the best choice, but should I pair it with a true deep cycle or purchase a matching dual purpose? I am not ready to throw away a four month old battery just to get two six volt models as I don't boondock that much. Thanks.

Finding true Deep Cycle in 12 volts may be ... hard to do.. (yes they do make them) may also be expensive.

Consider, if you have the head room, a pair of GC-2 Golf Car batteries (Which by the way brings up a suggestion as to where to look for deep cycle 12 volt,, golf car battery stores).

These half-12 volt batteries (Think of them that way) hold 220-230 (Some as much as 250) amp hours... They are true deep cycle and when you wire the two of them in series they basically become one 4D size 12 volt battery DEEP CYCLE type.

Treat them like that

Some numbers
Group 24, about 75 HA at the C/20 rate
Group 27, around 95, Group 29, around 105 and
Group 31, around 130

4D and 8D 220-270 depending on speciics.

Weight per amp hour at 12 volts.. Nearly identical across all sizes.

GC-2 six volt pairs in series,,, 220-230 amp horus

All ratinggs are +/- about 5%

[MEXICOWANDERER]

Anyone here want him to flap his arms and run around like a chicken?

[Dakota98]

jrnymn7 wrote:
Do not throw the battery away... buy a boat, instead, 🙂

Good advice. It will be the happiest day of your life. :B

The next happiest day will be when you SELL IT !!! :h

[doughere]

I would check how old the battery is!!

When we got our 5er, it had a single #27. The battery failed less than a year in. It was already so old that we would have gotten about %10 in warranty from Interstate; got a Wally World #27; that lasted about a year. Got 2 no-name GC's, they're about 7 years old now; recently did a load test, and they still have about 80% of their capacity.

Doug

[grizzzman]

TomG2 wrote:
My four month old camper came with a dual purpose marine battery and I want to increase my electrical capacity. I realize that dual purpose is not the best choice, but should I pair it with a true deep cycle or purchase a matching dual purpose? I am not ready to throw away a four month old battery just to get two six volt models as I don't boondock that much. Thanks.

I would suggest getting another similar battery and i would get the most capacity you can afford while your at it. Good luck with it!