Battery Choice Opinion Please UPDATE

[BFL13]

Updated 26 April
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Thinking of getting one of these to replace an old pair of wet 6s, where the price here is similar to new 6s.

Not sure if it is suitable for RV use doing 50-90s sometimes but mostly 75-100s. Is it really a deep cycle? Some graphs etc scroll down. Also is this anything like those big AGMs like Mr Wiz and PT have (although theirs are not the same as each other's ISTR-something about starved or whatever acid? )

I see their spec charging voltage is fairly low at 14.1-14.4. I have 12v deep cycle AGMs in 27 format that want 14.8ish. But their float voltages are the same at 13.7ish.

Thanks for any info/advice

http://www.esg100.com/index.php/product/index/g/e/id/35.html

[MEXICOWANDERER]

First order of the day. Find out where the "wall" is

Charge at 14.0, 14.1, 14.2, 14.3, 14.4, 14.5

When you move to the next higher step and the battery refuses the voltage the prior step is the correct one the finish absorbsion voltage. This has to be done before the battery ages.

A refusal would some amperage for a few seconds then back to no amps.

[BFL13]

Thanks all. Private sale. I went ahead and got one, but taking some risk it is any good. It is unused but not new. He said I could return it if it didn't pass my initial checks. It was at 13.04 sitting there. I will soon know if it is ok.

Advice noted not to use it for my big inverter draws. Intended to just run normal RV 12v stuff--say furnace and a couple lights under 20 amp.

Once it is installed in the RV it will stay there! 🙂 It is a monster.

[MEXICOWANDERER]

You can lift 150lb?

Silly Rabbit! That's why they make 18 year olds.

[landyacht318]

Looks like another rebranding of the UPG battery to me, but who really knows if the internals are the same.

Look up the 8d UPG battery and compare specs.

Seems you like the paired UPG 27's you have.

Regarding the AGm and thin plates, I am close to the 800 deep cycle range on my Northstar and at least a hundred of those are below 50% SOC and many of those are down to as low as 25% SOC

But Northstar is no Budget thin plate battery.
If I take 45 of its 90AH original rating, at twice the 4.5 amp rate at which it earned its rating, the voltage still rebounds to well over 12.2v with loads removed, and it can still easily start my engine depleted 65 of its 90AH.

[2oldman]

You can lift 150lb?

[MEXICOWANDERER]

Read the specs. Opinion

• Weight versus ampere hours 20 hour weight
• No where near the weight of a standard 8-D AGM
• Yet is advertises similar ampere hours
• Must have THIN plates
• 100 amp max limit recharge OK. Observe 20% minimum recharge
• Can your solar exceed 48 amperes continuous?
• I would never take a thin plate AGM to less than 50% SOC regularly. Over-amp really thin plates and they will warp
• This is a standby battery. Low charge and discharge amperes
• This is not a bad choice -- but I would pay attention to the caveats

[BFL13]

Thanks, do you think the specs with their "cycle use" and also "standby use" indicate that it can be used as a deep cycle battery
EDIT--ok was answered-thanks.

[MrWizard]

I looked at the specs, the idea is similar but the power specs and chemistry are a little different
The more lead per amphr, the better
Examples
Car jar 63# 105 amp hrs. 0.6 pound of lead per Amphrs , thin plates

Gc pair 126# 220 Amphrs , 0.57 pound of lead per amphr, put thicker plates

This battery 148.8# 250 amp hrs. 0.59 pound of lead lead per amphr, should be thicker plates, size of to gc in one pkg

My battery 102# 135 amp hrs. 0.75 pound of lead per amphr

I think "acid starved" is more lead , less acid per amphr rating

Granted my calculations are based on total weight, which includes the plastic case and the acid,
Mfg don't publish the weight of the lead, in the battery

I think this would perform about the same as two GC, maybe slightly better, being they are AGM

[BFL13]

luvlabs wrote:
Good old 220 amp/hr golf cart deep cycle batteries work very well. Splurge and get yourself a battery watering system. Still cheaper than AGMs.

In my particular case the price is temporarily about the same as a pair of new 6s for about the same AH (250). Problem is whether one 6GFM250 would perform about the same as a pair of 6s before grabbing one before they are gone.

[luvlabs]

Good old 220 amp/hr golf cart deep cycle batteries work very well. Splurge and get yourself a battery watering system. Still cheaper than AGMs.