Deep Cycle Battery Suggestions

stugpanzer wrote:
I might need to get two 12 volt deep cycle (house) batteries for my coach. I have been looking at going with gel batteries but I am curious if anyone else has gone that route and have suggestions for what I may want to look at.

OK thanks to one company there is a lot of confusion about GEL batteries.. Here are facts

GEL batteries are the WORST choice. you need to be very very very careful feeding them. They are OK on discharge but they need to be babied when they are charging Charge 'em too fast and POOF. they die.

Flooded wet is much more forgiving.. also much cheaper. My preferred battery is the Golf Car GC-2 you put two six volt GC-2's in series and like magic you have a 12 volt. Roughly a 4D for capacity but way less expensive and way easier to wrangle (install).

AGM .. The battery company I mentioned makes AGM's but labels them GEL. are about as far from GEL as you can get. They can be charged same as Flooded wet. and in fact one brand (LIFELINE) says you can charge theirs much faster.. They are also more expensive.. If you are going this route I'd recommend Lifeline AGM.

Finally today we have a lot of what I call "Exotic" battery types. SiO2, Lithium, and more... Sadly That's about all I know about them.

Lead acid: Flooded wet like the Most common golf car need to be fed a bit of DISTILLED water from time to time but last a long time and are the lowest cost
Maintenance free. You can not water them. Shorter life higher price
AGM also can not bet watered but generally do not need it. The supporters claim longer life, I've not seen evidence both from the Makers or from experience.

Keep it simple. 2 AGM batteries, Either 6V or 12V.

midnightsadie wrote:
plugged in most the time? get two wal mart deep cycle marine, the biggest that will fit. mine are four years old and work great. and you won,t break the bank.we some times boondock for a week end no problem.

I use 100A Delco batteries from Sams Club, likely the same battery different label.

plugged in most the time? get two wal mart deep cycle marine, the biggest that will fit. mine are four years old and work great. and you won,t break the bank.we some times boondock for a week end no problem.

stugpanzer wrote:

theoldwizard1 wrote:
Much better off with two 6V golf cart batteries.

AGM 6V golf cart batteries do exist but they are $$$ (Trojan T105-AGM) and would have to be ordered through a golf cart store or solar power store.

I need to double check and see if my two house batteries are 12volt or 6volt. Thanks for the input!

Not really a problem going either way. If you get two 6v batteries you just wire them in series.

Hi,

If you want possibly the toughest battery available, look closely at SiO2 chemistry. This is what I've gleaned so far:

They can be discharged to stone bone dead 620 times without dying. After those 620 cycles, 80% of OEM capacity remains. They are about 1/2 the price of LI. They can be used and charged at -45 c to +65 c. (-49 f to 149 f)

At 50% discharge cycles are 2800 (80% of OEM left)

At 80% discharge cycles are 1500 (80% OEM left)

They can be draw on at a rate of 9C for 5 seconds.

They do not need to be recharged to 100%, but once a month a full charge is recommended.

From the seller:

“This battery has 1200 Watt Hours of storage.

You can access 100%, but it is recommended that you do not regularly discharge over 80% because it will shorten the lifespan of the battery.

At 80%, the usable capacity is 960 Watt Hours of storage. Max peak discharge is, (for the 100 amp-hour) is 900A (5s) at 25 degrees C.

Constant Amp discharge rate is 320A (about 5 minutes until the battery is fully discharged). For charging the rate is .25C (4 hour) charge rate (25A for 1 100Ah 12V battery).”

The only negative is weight. The "best buy" is currently the 100 amp-hour battery."

For USA pricing go here:

https://azimuthsolarproducts.com/product-category/batteries/sio2/

I've found the Azimuth company extremely responsive to questions, often replying on the same day.

The manufacturer is the Canadian company https://soneil.com/

Technical Brochure is:

https://soneil.com/wp-content/uploads/2018/07/12-EFSN-100.pdf

time2roll wrote:
Stay away from GELL. Need special charging to limit voltage and amps.

Get AGM if you want no maintenance. I recommend Lifeline.

Otherwise a couple flooded batteries from Costco is a good value.

Or is there something special we should consider in the recommendation? Two batteries seems light for such an RV but maybe you are almost always plugged in.

thanks for the tip. This coach is set up for two batteries and yes, we do stay plugged in most of the time.

Stay away from GELL. Need special charging to limit voltage and amps.

Get AGM if you want no maintenance. I recommend Lifeline.

Otherwise a couple flooded batteries from Costco is a good value.

Or is there something special we should consider in the recommendation? Two batteries seems light for such an RV but maybe you are almost always plugged in.

theoldwizard1 wrote:
Much better off with two 6V golf cart batteries.

AGM 6V golf cart batteries do exist but they are $$$ (Trojan T105-AGM) and would have to be ordered through a golf cart store or solar power store.

I need to double check and see if my two house batteries are 12volt or 6volt. Thanks for the input!

If you don't mind checking battery cell electrolyte levels and battery corrosion cleaning then two GC-2 6V batteries would do just fine. Otherwise I'd suggest two 12V AGM batteries like Renogy 12V 100Ah units...