Lead Carbon Batteries ?

[John in Santa Cruz]

We did zero camping in the summer. I spent a good part of the late summer, early fall converting our 2005 17B from the stock single group 27 12V to a pair of 240Ah 6V Lead carbon batteries. Installed a BMV-712 and upgraded to a 35A Progressive Dynamics Inteli-power converter/charger. I also spliced in a remote pendant as we keep the rear dinette converted to a bed and it would be nearly impossible to monitor the LED on the 12V board.


We have now been out 2 times for 5 days and 4 nights running the furnace etc, and have not reached a 60% SOC yet. This last trip, I tested our 2200 watt gen for a 2 hour period to simulate a Provincial Park and it brought the batteries back up to a 82% SOC.


Hope to squeeze at least one more trip in before the weather gets into regular freezing.

FWIW, you probably should have gotten a PD 55A converter for the dual GC batts so they'd charge faster



EDIT: I moved this from a different thread where batteries were quite off topic

 

[BC Rockcrawler]

FWIW, you probably should have gotten a PD 55A converter for the dual GC batts so they'd charge faster

The charging specs for the Lead Carbon AGM are 24 amps recommended charge current, 48 amps max charge current. I split the difference and went with the 35 amp charger to get maximum life from the pair of batteries.


From my past experience with the group 27 12 volt and the old 45 amp single voltage charger, the recovery time from 60% is very good with the 35 amp 3 step charger.

 

[John in Santa Cruz]

The charging specs for the Lead Carbon AGM are 24 amps recommended charge current, 48 amps max charge current. I split the difference and went with the 35 amp charger to get maximum life from the pair of batteries.

huh, 24A seems pretty low for a 220-ish AH flooded cell... The 55A converters rarely output 50A in lead-acid mode in my experience, although they do output a solid steady 50A+ in lithium mode until the batteries are over 90%

 

[BC Rockcrawler]

huh, 24A seems pretty low for a 220-ish AH flooded cell... The 55A converters rarely output 50A in lead-acid mode in my experience, although they do output a solid steady 50A+ in lithium mode until the batteries are over 90%

My new Lead Carbon batteries are not flooded cell. They are AGM and use a carbon and lead plate for the negative side of the battery.


The advantages of this newer battery tech is that they can work down to -40C, both on discharge and charging too. They charge a lot faster on less amperage than a typical flooded cell. They will take repeated partial charging without causing the plates to sulphate and shortening battery life. They can be repeatedly discharged to 80% DOD and still get 2,000 cycles from them. 50% DOD will allow the battery to have about 3,000 cycles.


I did quite a bit of research along with being a Journeyman Electrician who has worked on several types of battery banks, these made the best choice for me. Lithium iron phosphate are the ultimate set up but being retired, they were outside my budget. Lead Carbon are halfway between flooded cell and lithium both in performance and cost. So far, the new charger and batteries have checked all the boxes that I had set as parameters.


I have attached the sec sheet for the battery.

 

[MrLynn]

When my two flooded lead-acid batteries bite the dust, I figure I'll get AGMs, too. No need for lithiums, which besides being expensive, seem (from reading endless Forum posts) finicky about cold weather. I leave my batteries in the Escape all winter, on 30A shore power from the house, and no problems.

Plan to head south to VA tomorrow. A little nervous about overnights in PA/MD state parks (we geezers are taking three days do go all of 650 miles!), with subfreezing nights, since not yet winterized, but with a little water in the fresh tank and with furnace on and foam underneath, I think we'll be OK.

Also have the heat pads on the tanks—never used them yet. Do they run on 12V? Shouldn't matter, as we'll have shore power in the campsites.

I'll see what turns up outside our back window and report, thus returning this thread to topic.

 

[John in Santa Cruz]

pretty sure heat pads on your tanks are going to be shore power only...

interesting that vendor claims their lead-carbon battery is good for 1000s of cycles, other vendors, such as Victron, claim 100s of cycles. OTOH, thats a LOT of cycles, my SOK Lithiums claim like 7000 cycles at 80% discharge or something insane, that's like 4000 watt*hours every day for 20 years (my batteries are 5260WH combined)

 

[Rossue]

pretty sure heat pads on your tanks are going to be shore power only...

interesting that vendor claims their lead-carbon battery is good for 1000s of cycles, other vendors, such as Victron, claim 100s of cycles. OTOH, thats a LOT of cycles, my SOK Lithiums claim like 7000 cycles at 80% discharge or something insane, that's like 4000 watt*hours every day for 20 years (my batteries are 5260WH combined)

Hey Moderator Dude- how's about taking the last 5 posts and moving them off this thread onto the appropriate one about batteries! TIA

 

[John in Santa Cruz]

Hey Moderator Dude- how's about taking the last 5 posts and moving them off this thread onto the appropriate one about batteries! TIA

done... :whistling: