Gel Cell Battery

[J-Rooster]

When I got into my RV this morning it wouldn't start. I had to use the battery boost from my coach batteries to get the engine started. My chassis battery is a self contained Gel Cell battery around a year old that is dead and seems not to be taking a charge. I've been charging the Gel Cell battery for about 8 hours and it reads that it is still in the red (red indicator light means battery is not fully charged) on my battery charger. The green light on my battery charger indicates a full charge. I talked to my son and he told me Gel Cell batteries are very good batteries but, they need to be ran all the time not here and there (I've had my coach out twice in the last year). Has anyone experienced using a Gel Cell battery in a RV?

[J-Rooster]

smkettner wrote:
Pretty sure the factory Optima website is very clear that they make AGM batteries.
Nothing else. No gel unless to explain that the battery is not a gel battery.

Sometimes these are referred to SLA because they do fall into the Sealed Lead Acid group same as gel.

Thanks for explaining that term to me (SLA).

[J-Rooster]

usersmanual wrote:
The whole top of the battery is Red! And it says Optima, AGM, High Performance Battery!




well then its a Absorbed glass mat battery not a gel cell as Optima claim there AGM

Thanks, The red top battery is completely self contained, I didn't mention that!

[J-Rooster]

rgatijnet1 wrote:

J-Rooster wrote:
Thanks for everyone's help! Battery is charging at 14.5 and everything is working!

That's great. According to my OBDII gauge, when the engine alternator on my coach needs to charge the batteries, it is usually at 14.4-14.5 volts. Sounds like everything is under control now.

Thanks, Ron

[rgatijnet1]

J-Rooster wrote:
Thanks for everyone's help! Battery is charging at 14.5 and everything is working!

That's great. According to my OBDII gauge, when the engine alternator on my coach needs to charge the batteries, it is usually at 14.4-14.5 volts. Sounds like everything is under control now.

[time2roll]

Pretty sure the factory Optima website is very clear that they make AGM batteries.
Nothing else. No gel unless to explain that the battery is not a gel battery.

Sometimes these are referred to SLA because they do fall into the Sealed Lead Acid group same as gel.

[usersmanual]

The whole top of the battery is Red! And it says Optima, AGM, High Performance Battery!




well then its a Absorbed glass mat battery not a gel cell as Optima claim there AGM

[J-Rooster]

Thanks for everyone's help! Battery is charging at 14.5 and everything is working!

[time2roll]

J-Rooster wrote:
I cleaned up the label. The battery has a red top that says Optima, AGM, High Performance Battery. House batteries do very well because there hooked up to a solar trickle charge. It's taking forever to get Chassis Battery to accept a charge! I'm using a Cen Tech, 50 amp charger! Thanks, John

Over discharged battery will have very high resistance and you may only get a couple amps in the first hours before it starts to ramp up. Does it show amps going in? I agree use max amp setting. Especially for AGM.

If standing voltage is too low the charger may turn off assuming something is wrong. You may need to jump start the battery from the house and restart the charger.

Consider a Trik-L-Start combiner to send a bit of that solar power to the chassis battery.

[MrWizard]

take the charger OFF trickle
put it on regular charge

[GordonThree]

The charger doesn't appear to be computerized, so it shouldn't care about a low voltage. My guess is it won't deliver much current until the voltage comes up.

There is a lead / AGM switch, make sure you're on AGM 🙂

Give it time, hopefully you can recover some capacity, AGM are more forgiving than flooded batteries.

[J-Rooster]

MrWizard wrote:
i've never seen Gel batteries in an RV
are you sure you don't mean AGM

and Optima is a spiral wound AGM

Absorbed Glass Matt aka AGM is different from Gel
both are sealed, but gel requires special charging

Yes, Mr. Wizard it's a AGM!

[J-Rooster]

rgatijnet1 wrote:

J-Rooster wrote:

rgatijnet1 wrote:
On my inverter/charger, it had a different setting for the standard lead acid batteries and for the AGM batteries. Make sure that the charger is set for the type of battery that you have.

Thanks for the info Ron, I'm learning a lot today, I'll check the setting on my inverter!

Here is what it says on my Xantrex inverter:
Battery Charging
Completely charging wet cell deep-cycle
batteries requires the battery voltage to be
raised beyond what is known as the gassing
point. This is the voltage at which the battery
begins to bubble and gas is given off. If
charging stops short of this point, sulfate is left
on the plates and deterioration of the battery
begins. The gassing point will vary with battery
temperature.
At 77 ?F, the gassing point of a 12-volt
battery is about 14.0 volts.
AGM and Gel cell batteries must not be
charged to their gassing point. In fact, high-
voltage charging that gasses these batteries is
harmful to them. They typically require a lower
bulk charge voltage and a higher float voltage
than wet cell batteries. Consult the battery
manufacturer for specifications.
Freedom Battery Chargers
Freedom battery chargers are designed
to overcome the limitations of conventional
chargers by utilizing three distinct charge
stages, each designed for optimal charging of
wet, gel cell and AGM deep-cycle batteries.

Thanks for the info very helpful. Ron next to my inverter off/on switch it says Ext. Power and a green light is on? What is that about? Thanks, John

[J-Rooster]

smkettner wrote:
Clean up the label and post the actual battery model and brand etc. for best answers.

How does your house battery stay charged? Are you plugged in or solar? Very easy to pass some of this power to the chassis battery.

Depending on the battery and trickle charge it could take a week to charge. Then it is hard to tell if the battery will charge at all. Best to have a 10 to 40 amp charger.

I cleaned up the label. The battery has a red top that says Optima, AGM, High Performance Battery. House batteries do very well because there hooked up to a solar trickle charge. It's taking forever to get Chassis Battery to accept a charge! I'm using a Cen Tech, 50 amp charger! Thanks, John

[J-Rooster]

GordonThree wrote:
J-Rooster:

What charger are you using? Some "smart" chargers will refuse to charge a battery if the voltage is too low, that red light might stay red the entire time.

Gordon, I'm using a Cen Tech, 50 amp charger, it has 3 settings #1 fast jump start setting, #2 regular charge setting, #3 trickle charge setting. I'm currently using the trickle charge setting.