Forum Discussion
RoyB
Aug 18, 2014Explorer II
When I compare two GP24 85AH Standard Issue 12VDC battery in parallel with the Trojan T105 6VDC batteries in series to produce 12VDC the results stand out which will perform longer camping off the power grid.
This is a T105 Spec sheet similar to the GOLF CART GC2 6VDC Batteries from COSTCO.

Connected in series will look like this

The big thing that stands out for me is these two T105 6VDC 225AH Batteries in series will produce 12VDC for 447 minutes (7.45 hours) before going to 0% Charge State. These two 6VDC GOLF CART batteries will cost around $90 each from COSTCO.
This is similar 24TMX 85AH 12VDC Battery spec sheet similar to the 12VDC 85AH Interstate Batteries

Connected in parallel will look like this

These two 12VDC 85AH Batteries in Parallel will only produce 12VDC for 280 minutes (4.6HOURS) before going to 0% Charge State. The cost of each battery is about the same as the GC2 batteries from COSTCO ($90 each).
This alone says the two GC2 type golf battery will provide around 50% more capacity than the two GP24 85AH batteries you have for the same price.
The trouble I would have with just two 6VDC batteries in series is if one goes bad you will only have 6VDC of usable DC voltage that will not be any good use for you with the trailer 12VDC system.
You kinda have to think about the two 6VDC golf cart batteries as one very large 12VDC batteries. Now having two groups of two 6VDC batteries connected in series is a very less expensive way to get some real 12VDC Capacity for camping off the power grid. This setup would provide 25AMPS DC current for around 14 hours of run time before totally discharging the batteries.
Of course you NEVER EVER ever want to discharge your batteries lower than 50% charge state as this may do damage to your batteries performance...
Just my thoughts here...
Roy Ken
This is a T105 Spec sheet similar to the GOLF CART GC2 6VDC Batteries from COSTCO.

Connected in series will look like this
The big thing that stands out for me is these two T105 6VDC 225AH Batteries in series will produce 12VDC for 447 minutes (7.45 hours) before going to 0% Charge State. These two 6VDC GOLF CART batteries will cost around $90 each from COSTCO.
This is similar 24TMX 85AH 12VDC Battery spec sheet similar to the 12VDC 85AH Interstate Batteries

Connected in parallel will look like this

These two 12VDC 85AH Batteries in Parallel will only produce 12VDC for 280 minutes (4.6HOURS) before going to 0% Charge State. The cost of each battery is about the same as the GC2 batteries from COSTCO ($90 each).
This alone says the two GC2 type golf battery will provide around 50% more capacity than the two GP24 85AH batteries you have for the same price.
The trouble I would have with just two 6VDC batteries in series is if one goes bad you will only have 6VDC of usable DC voltage that will not be any good use for you with the trailer 12VDC system.
You kinda have to think about the two 6VDC golf cart batteries as one very large 12VDC batteries. Now having two groups of two 6VDC batteries connected in series is a very less expensive way to get some real 12VDC Capacity for camping off the power grid. This setup would provide 25AMPS DC current for around 14 hours of run time before totally discharging the batteries.
Of course you NEVER EVER ever want to discharge your batteries lower than 50% charge state as this may do damage to your batteries performance...
Just my thoughts here...
Roy Ken
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