Second Set of 6 Volt Batteries

[Cowichan]

I have a new 5.0 with dual 6 volt lead acid batteries and a roof mounted solar panel.
I am thinking of installing a second set of 6 volt batteries in parallel with the existing set. Does anyone have experience in doing this?
I wanted to stay away from adding a marine type battery selector switch and connecting the batteries to the "B" charging position on the solar controller. It would be less hassle to have all 4 batteries charge off the "A" terminal of the controller.

[UncleTim]

No. I am waiting for mine to fail so I can rip them out and install lithium.


I hope they take their time.

[Vermilye]

I considered it, but adding an additional vented battery box and 150 pounds of batteries convinced me to dump the original 6V batteries & switch to Battleborn lithium. I currently have 3, and the combined weight is still less than the original 6V batteries with well over twice the usable amp hours.

[Cowichan]

At a cost of over $3,000 for lithium, it isn't an option for me. The weight of a second set isn't that significant for me.

[Perry Butler]

Originally Posted by Cowichan

At a cost of over $3,000 for lithium, it isn't an option for me. The weight of a second set isn't that significant for me.

We felt the same way. We now have two 260 ah SiO2 batteries easily giving us 200 usable ah's for $1,000. So far they are working exactly as expected: quick to charge and have yet to get below 90% state of charge.

Enjoy,

Perry

[Randy in Maine]

I would suggest just waiting a while to see if you ever really run low on battery power. The SiO2 batteries look more appealing to me that the lithiums.

[ChuckBC]

I agree with first determining the usage on the battery bank then look at the value of the upgrade.
If you are using a large inverter, appliances, off grid then battery storage, cycling becomes a bigger consideration in RV use.

With wet cells you only have 50% amperage for use given size/weight, 1 cell goes should replace all 4, need a good monitoring routine and effective charging to get towards 100%.

I had a sailboat with 4 x 6V but also had a high output alternator, external 3 stage regulator, combiner, adjustable mounted solar panels and monitored system. Wiring needed to match system. We were out in the open in the PNW at all times to maximize solar and even then found motor time was some times needed to max charge batteries.

For us in our trailer the 2 x 6V with 190W panel is sufficient, easy to charge and maintain. I have a less complicated, simple, easy DC life and a Walmart is somewhere down the road if needed.

[TTMartin]

Originally Posted by UncleTim

No. I am waiting for mine to fail so I can rip them out and install lithium.

I hope they take their time.

Same here.

I'd never consider adding a second set of lead acid batteries they take up too much space and weigh too much.

[Brian B-P]

Steve (hotfishtacos) has four batteries in his 19'. He had all four on the tongue then moved two of them to the rear bumper, but of course appropriate placement depends on the trailer model and other factors. I don't recall how he has them wired.

[hotfishtacos]

The rear bumper was heavily modified to include the two battery trays then I wired them from the front to the back in parallel with EWCS 1/0 Gauge Premium Extra Flexible Welding Cables. I switched to AGM batteries last year for reduced maintenance.

[Rossue]

Check out Will Prowess' review of lithium batteries at about half the price of Battleborn.
https://youtu.be/RxMIs0PXrBw

[rubicon327]

Originally Posted by Rossue

Check out Will Prowess' review of lithium batteries at about half the price of Battleborn.
https://youtu.be/RxMIs0PXrBw

Don't forget to include the Bestgo batteries available from Electric Car Parts in your consideration for "more affordable" lithium. Excluding tax I got 400AH for $1,930 (they are selling higher now but still a decent value IMO). To achieve the same capacity with Battle Born you'd need four individual 100AH batteries wired in parallel which would run $3,600. Almost twice the footprint and more weight as well. Even their 270AH format with a single BMS is $2,800 which is an even higher $/AH.

https://www.youtube.com/watch?v=F2ynIbGsc1E

[TZBrown]

Originally Posted by Cowichan

I have a new 5.0 with dual 6 volt lead acid batteries and a roof mounted solar panel.
I am thinking of installing a second set of 6 volt batteries in parallel with the existing set. Does anyone have experience in doing this?
I wanted to stay away from adding a marine type battery selector switch and connecting the batteries to the "B" charging position on the solar controller. It would be less hassle to have all 4 batteries charge off the "A" terminal of the controller.

At the time we picked up our 21c we had just sold our previous stick build TT.
I removed a brand new pair of 6V batteries and all of the solar and returned it to stock configuration.

I added a vented box to the passenger rear of the 21 and installed the batteries there. No second transfer switch, but did add a breaker, betewwn the battery banks https://www.amazon.com/Blue-Sea-Syst...04XXOW0E&psc=1.

The pairing of the batteries, though not optimal, has been OK using just a simple parallel circuit between them. I used the wire I had available which was 2 gauge.

With 290W of solar and the battery bank there is very few times we are below 12.4V even during winter/ low sun angles and running the furnace most nights

When I have issues with these batteries I will probably change to Lithium, but we run no inverters, so until then all is well, only the weight penalty and adding water 2x per year