Converting GC2 Batteries to Lithium or AGM

[Utclmjmpr]

I presently have 4 GC2 batteries in series-parallel,, and would like to convert to lith, which I know nothing about other than they do NOT sulfate >>>Dan __ Lithium batteries are now priced competitively with lead acid .. I also have 450 watts of solar on the roof and a DUVAC 160 amp alternator that will charge two systems at different voltages while keeping them isolated....

 

[Kirk]

 

[Utclmjmpr]

Thanks Kirk,, I knew all the comparisons, thats why I want to convert ,, I just need some of the technicalities that I will run into.. Present system powered by a Xantrex Freedom 3000SW
converter charger..

 

[RV_Lee122]

Swap them out with modern lithiums that have an app so you can monitor whats going on from your phone. Only potential issue is your alternator may not like them as they require 14 volts and not 13, so the alternator runs constantly, it can fry it. But I'd hook them up and see whats going on and what it needs, if anything. The app will show charge amps from being plugged in, from your solar, from alternator

Epoch makes a good battery that is good value

 

[Utclmjmpr]

I have decided to go to AGM and get a non sulfate system and not have be concerned about any other changes , thanks all for the help ..>>>Dan

 

[Kirk]

I have decided to go to AGM

Before you buy the new batteries, check out this user manual, as it does state that you can charge lithium batteries.

 

[Mark_K5LXP]

I have decided to go to AGM and get a non sulfate system

Hate to break it to you but AGM being lead acid "sulfates" too. Not sure if their other attributes are sufficient to solve the problem you're having.

Mark B.
Albuquerque, NM

 

[Utclmjmpr]

I thank you Kirk,, I installed the Xantrex about 10 years ago and did not know it had that capability..>>>Dan

 

[Utclmjmpr]

Mark,, I'm done with the routine of adding water to batteries and removing acid residue on everything in the neighborhood of the battery box.. AGM batteries do not require all this maintenance and are now competitively priced,, nuf said.. I also gain in that with 4 12V batteries in parallel instead of 4 6V batteries in series-parallel,, I move from having 250 amps at 12V,, to having 400 amps at 12V >>>Dan

 

[DonTom]

, I move from having 250 amps at 12V,, I will have 400 amps at 12V >

How is that? Does each battery have more AH?

If each battery is the same:

Voltage doubles in series, but not the amps or AHs. You get double the wattage because the voltage is double than one battery at the same AH, but the AH is unchanged.

Current adds in parallel so then you get double the amps & AH but at the same voltage,

Same wattage always with like batteries no matter how they are configured.

IOW, you can change the voltage, current, AH with an equal number of batteries but never the wattage or WH, which is the true power.


-Don- Auburn, CA

 

[Isaac-1]

Most Xantrex inverter chargers built in the last 25 years have 4 stock charging profiles, the one label GEL2 or Cool Gel, is very close to the optimal charging profile for LiFePo4 batteries if you disconnect the optional temperature compensation probe (if you have one) so should work fine if you decide to go the LiFePo4 route.

If you have concerns about damaging your alternator you can add a 50 amp DC-DC charger inline in the connection between the alternator and the batteries, this will cost you around $250-$300 extra something such as Amazon.com

 

[John From Detroit]

I also gain in that with 4 12V batteries in parallel instead of 4 6V batteries in series-parallel,, I move from having 250 amps at 12V,, to having 400 amps at 12V >>>Dan

4 GC2 in Series/parallel is between 420 and 460 amp hours at 12 volts. (At the C/20 rate)

 

[Mark_K5LXP]

removing acid residue on everything in the neighborhood of the battery box.

Not sure if that's what you meant by 'sulfation' - that's a term for an internal issue. All I've ever run is flooded batteries and have zero issues with terminal corrosion or compartment mess. It can be done with proper caps and watching charge profiles. AGM's will work OK, just that per Ah they're about 2x more expensive than flooded.

Mark B.
Albuquerque, NM

 

[Lou Schneider]

Not sure if that's what you meant by 'sulfation' - that's a term for an internal issue. All I've ever run is flooded batteries and have zero issues with terminal corrosion or compartment mess. It can be done with proper caps and watching charge profiles. AGM's will work OK, just that per Ah they're about 2x more expensive than flooded.

Mark B.
Albuquerque, NM

And at current prices about 2x more expensive than lithium.

 

[John From Detroit]

Not sure if that's what you meant by 'sulfation'

The acid in a Lead Acid battery is Sulfuric, (H2SO4) so it's Sulfur SPlies off from Hydrogen and Oxygen.

Well over time the sulfur the hydrogen and sulfur "Break" their bond leaving elemental sulfur which condenses out onto the plates in the battery and prevents them from working properly. "Desulfation" Gets rid of the Sulfur. also tends to smell like rotten eggs (Which odor is also Sulfur based) This process can extend battery life.. IT also boils off some of the water in the battery.

 

[UTTransplant]

When selecting your batteries, make sure they have cold temperature protection. Lithium batteries can be damaged if charged below 32F. Take note that this is the temp at the batteries, not necessarily the outside ambient temp. Any good battery will have it, but there are some cheaper versions that don’t. Note you can use the batteries below 0F, but you can’t charge them. Since we travel in shoulder seasons and at high elevations, we got self-heating versions. Adds some cost, but it is handy to start the batteries charging when the sun comes up even in cold temps.

 

[Lou Schneider]

When selecting your batteries, make sure they have cold temperature protection. Lithium batteries can be damaged if charged below 32F. Take note that this is the temp at the batteries, not necessarily the outside ambient temp. Any good battery will have it, but there are some cheaper versions that don’t. Note you can use the batteries below 0F, but you can’t charge them. Since we travel in shoulder seasons and at high elevations, we got self-heating versions. Adds some cost, but it is handy to start the batteries charging when the sun comes up even in cold temps.

I think it's been a couple of years since I've seen any lithium battery sold without cold temperature charging protection. It was a problem with a few low cost LiFeP04s before the problem was widely recognized but internal Battery Management Systems incorporating cold temperature protection, like prismatic cells, are now commodity items.

 

[Isaac-1]

Another potential option instead of investing in heated batteries is to relocate the batteries into the climate controlled part of the RV.

 

[UTTransplant]

I think it's been a couple of years since I've seen any lithium battery sold without cold temperature charging protection. It was a problem with a few low cost LiFeP04s before the problem was widely recognized but internal Battery Management Systems incorporating cold temperature protection, like prismatic cells, are now commodity items.

They should Lou, but I just read on a forum frequented by van conversions that a guy who bought the cheapest he could find got a nasty surprise. They were batteries bought and installed this year.

 

[Gary RV_Wizard]

View attachment 2472238

IMO the GC2 Usable Capacity and Lifespan shown in this comparison are pure hogwash, but Lithium is till better.

Those numbers are more typical of the so-called Marine/RV battery than a GC2 (golf cart) deep cycle. That 50% is pure internet meme and, in RV use, a GC2 typically sees 7 or more years and 1000+ cycles.