diy solar

diy solar

260ah or 100ah cells for travel trailer battery build.

billtrev

New Member
Joined
May 17, 2021
Messages
3
The two FLA golf cart batteries (240ah total, 120ah usable when they were new) on our travel trailer are five years old and are approaching the end of their useful life.
Thinking about building a 12v LiFePO4 to replace them with.
Trailer has 400 watts of solar with a Bogart Engineering SC-2030 Solar Charge Controller and TriMetric TM-2030 Battery Monitor and the old pre-lithium Progressive Dynamics 4655 converter. Mostly dry camp/boondock so converter isn't used much. I plan on adding a Dc to Dc charger for the truck to trailer connection.
Trailer has a small Morningstar SureSine SI-300 watt inverter currently installed. Depending of future battery I may add an inverter large enough to power a small microwave.

First thought was a four cell 280ah battery with EVE or Lishen cells.
Then I read a bunch of posts about not using cells above 200ah in mobile applications.
Looked at CALB and Fortune cells
That got me thinking of using 16 100ah plastic cased cells or 16 AL cased 105ah cells with two (or possibly 4) Overkill 120 amp BMS.
Then I read about the difficulties of keeping multiple paralleled batteries balanced - which leads me back to
one or two 260ah batteries.

Any advise or insight would be appreciated.

Bill
 
Where did you see advice on not using a 280ah cell for a mobile application. There’s a lot of info here, but you do need to interpret it.
 
Where did you see advice on not using a 280ah cell for a mobile application. There’s a lot of info here, but you do need to interpret it.

I'm curious as well and would love to find the detail. I'm planning a mobile setup and hoped to use 280ah cells.
 
The quote below is from Nordkyn Design.
I have seen this reposted/quoted/paraphrased. Not quite sure how or if this applies to the
280ah cells for RV use.


"A sales manager at Sinopoly I was talking to was adamant about using 100Ah or 200Ah cells only for assembling marine battery banks, with 100Ah being preferred and 200Ah acceptable. Large cells simply don’t have the structural strength-to-weight ratio required to be taken to sea on board small crafts and would exhibit shortened life due to internal mechanical damage arising from on-going vessel motion. It is common sense: as a cell becomes larger, its internal weight increases much faster than the rigidity and surface area of the casing and the casing is all what holds the plates together in a prismatic cell."
 
It's interesting. Is there any empty space in a cell? I assumed none and obviously no electrolyte that is floating anything. I mean what they are suggesting could make sense and it might make perfect sense for some product, but I wonder if its really a thing for all prismatic batteries.
 
There are many forum members using 280AH cells without any problem. Just make sure you set up a good box or clamping device to keep the cells (and especially the busbar connected terminals) from moving. The cell terminals are the weak spot, and won't take a lot of movement.
 
Thanks for the input everyone.

I was about to pull the trigger on the 105ah EVE cells.
Then I noticed that the 105ah cells come with tiny little M4 hardware.
The thought of all those small screws (or even studs) in a mobile application concerns me enough
that I'm not really comfortable using them.
The M6 hardware on the 280ah cells seems huge by comparison, even if it is still too small.

Leaning towards the 280ah EVE cells.
 
Thanks for the input everyone.

I was about to pull the trigger on the 105ah EVE cells.
Then I noticed that the 105ah cells come with tiny little M4 hardware.
The thought of all those small screws (or even studs) in a mobile application concerns me enough
that I'm not really comfortable using them.
The M6 hardware on the 280ah cells seems huge by comparison, even if it is still too small.

Leaning towards the 280ah EVE cells.
I have both, and the 280AH cells are easier to work with connection wise. But realistically speaking, the 105AH cells are sized accordingly. The cells are smaller and will place less stress on the connections.
 
I would have no problem using the larger batteries in an RV/trailer. In a small to mid sized boat? Maybe not. The pounding they take can be very harsh.
 
Back
Top