Deep Cycle battery upgrade - advice wanted

[rob_9cc2d4]

Hey y'all!

I have a 2002 Yukon with a 100w solar panel feeding an ecoflow battery bank.

I'd like to use the spare battery compartment under the hood to upgrade my system with a proper deep cycle battery. I'm looking at a dual charging set up using the alternator when the car is running, and the solar panel to help the charge while we're stopped.

I've got my eye on some good renogy charge controllers but i'm still unsure what battery i should use.

i need something that i will be able to accept this dual charge and stand up to the heat under the hood. I've seen some conflicting info on AGM batteries and i know some are better than others for this kind of application.

does anyone have experiance with AGM or any other type of deep cycle battery that's kept under the hood and used for 12v appliances like a fridge, usb chargers etc? I'm not looking for 110 at the moment since everything we use is either 12v or USB.

Super grateful for any advice!

 

[genocache]

Years ago I bought a Sears Platinum AGM Marine battery(2012). It was around $250 then, exorbitant I thought at the time. 11 years later and it's still going strong. Mind you it is my only battery and doesn't run aux equipment. Though when I get around to putting in a dual system I'll try to go that route again.

 

[M Rose]

@Jim SoG can this be moved to the Electrical Help threads for more views?

 

[KonzaLander]

I have had good luck with AGM batteries from the autoparts store.

My setup is really simple, but it has been flawless, along with AGMs under the hood. Here is a thread about my simple dual battery setup: Basic Dual Battery Install in a '99 Land Cruiser

 

[shrdt]

If your going to put it under the hood, just get a lead acid deep cycle. Then all you need is a isolator to connect the two. AGM Batteries are more for places where you don't want acid leaking from the battery and I have read that they don't like the heat generated in the engine compartment. Also with a AGM you should use a DC to DC charger as their charge voltage is 14.6 instead of the 13.5 and most newer cars/truck use a variable charge alternator to save fuel so they may be chagrining at even lower voltages.

 

[M Rose]

If your going to put it under the hood, just get a lead acid deep cycle. Then all you need is a isolator to connect the two. AGM Batteries are more for places where you don't want acid leaking from the battery and I have read that they don't like the heat generated in the engine compartment. Also with a AGM you should use a DC to DC charger as their charge voltage is 14.6 instead of the 13.5 and most newer cars/truck use a variable charge alternator to save fuel so they may be chagrining at even lower voltages.

You’re confusing AGM with LifePo batteries. AGM (Absorbant Glass Mat) Batteries are lead acid batteries that are filled with a glass matt to absorb the acid. AGM have always been a direct replacement for flooded lead acid battery applications.

LifePo4 batteries are Lithium Iron Phosphate. And match much of what you say with one exception… Dakota Lithium makes a starter battery that can withstand the temps living under the hood as well as the huge amp draws required for starting the engine.

 

[shrdt]

You’re confusing AGM with LifePo batteries. AGM (Absorbant Glass Mat) Batteries are lead acid batteries that are filled with a glass matt to absorb the acid. AGM have always been a direct replacement for flooded lead acid battery applications.

LifePo4 batteries are Lithium Iron Phosphate. And match much of what you say with one exception… Dakota Lithium makes a starter battery that can withstand the temps living under the hood as well as the huge amp draws required for starting the engine.

Yes I know what the differences are and yes I am talking about the AGM. Both types have different charging requirements where AGM it is suggested to use a DC to DC charger since the charge voltage 14.6 and should be defiantly used for LifePo4. I am just not sure how well the AGM handles heat.

 

[M Rose]

Yes I know what the differences are and yes I am talking about the AGM. Both types have different charging requirements where AGM it is suggested to use a DC to DC charger since the charge voltage 14.6 and should be defiantly used for LifePo4. I am just not sure how well the AGM handles heat.

No not true Optima Red Top and Yellow Top are both AGM batteries and do not require a DC-DC charger. AGM charges at 13.8-14.5 volts just like normal lead acid batteries. Your alternator built after 1985 charges at 13.5-14.5 volts to handle the amperage demands of modern EFI, and other computer controlled functions of the vehicle. AGM batteries are used in military generator applications where the casing of the generator way exceeds under hood temps of a vehicle. (Military uses the Optima Red Top batteries in desert conditions on the 15 and 25k generators).