Gel battery safe Ah draw down percentage?

[leica69]

My camper has flooded lead-acid batteries and I know that the best practice is to avoid depleting the Ah capacity by more than 50%. A friend just got an RV with a gel battery. Does the same draw down percentage apply to gel batteries?
TIA, njb

[MEXICOWANDERER]

Gel battery construction is like a Hungarian actress...shower them with diamonds, platinum and obsessive compliments and constant care or you'll get a knife in your gut at midnight.

[beemerphile1]

I use MK Battery 8G24 gel deep cycles in my Aliner.

I treat them about the same as any other battery. They love deep discharges but should not be equalized as that can cause air bubbles and reduce capacity.

[pianotuna]

Hi leica,

Probably AGM will be needed. They may not have vented the battery bay to the great outdoors.

[leica69]

The RV my friend got is a 1999 Roadtrak 190 Popular. As for the battery type, I said gel because that was what is described on the original feature list. On reflection it seems very unlikely that the original battery is still in the vehicle. Bottom line--I don't know what's in there. I haven't seen the RV yet so I don't even know how many batteries there are. Any suggestions as to the best battery (batteries) to use?
TIA, njb

[wa8yxm]

I would be willing to bet his RV does NOT have a Gel type battery.. Most likely it is an AGM Why do I say this.. Two reasons.. AGMs have nearly replaced GEL in all applications and the bigger the battery the more likely it is to be AGM.

Why is this: Gel are very delicate, they need very careful care and feeding, AGM's on the other hand are far far more rugged and forgiving of charger errors.

OPTIMA: lists them as both GEL and AGM, but they are AGM. (Source: Optima).


Now how far can you suck 'em down.. Some discussion on that but frankly I believe the limits are more or less the same as yours

Starting batteries, designed for short bursts of high current, try to keep them as full as possible

Marine/Deep cycle, Try to keep them 78-80 minimum

True Deep cycle (NOTE: Much easier to find AGM deep cycle 12 volt than it is other types) 50 percent

Some folks however say you can go down to 20 percent safely... But I'm not one of them.

What I found when I tried some AGMs.

The were the last batteries I put in my coach when I got it.. I had the OEM batteries (Interstate U-2200), I had some Marine/Deep cycles, that pre-dated the motor home, And finally I added a pair of Group 31 MK AGMs.

When it came time to replace.. The AGM's were the first to go

The the older Maine/Deep cycles

And finally, last winter, the U-2200s (almost 9 years old, in fact 8 year 10 month) Also the startin battery (That was like 8 year six month)

[2oldman]

Gel?..really?