Using CALB CA180 cells in a RV battery bank.

Ken99

New Member
I'm designing a LiFePO4 battery bank for use on a travel trailer. The most cost effective option appears to be the CALB CA series of cells, especially the CA100 and CA180 versions. We don't off-road, but do drive down gravel roads to access USDA/FS or State campgrounds. I'm planning to secure the cells in a custom made aluminum box that I will shock-mount to the trailer frame using rubber isolators. Will Prowse's initial evaluation of these cells said they were great for static bank design but said nothing about RV use. Are CALB CA100/180 cells more, less, or same to damage compared to aluminum bodied cells in thhis sort of application?
 

Sojourner1

Itinerant
Most prismatic cells up to about 400ah cells should do alright in a mobile environment with the trailer attached to the truck. I've had my prismatic cells since April 2016 mounted in the front compartment of the 5th wheel, living off of the system in signature. Over 30k miles of highway and off road conditions (NF, BLM, State lands) and no problems so far.
 

Ken99

New Member
Most prismatic cells up to about 400ah cells should do alright in a mobile environment with the trailer attached to the truck. I've had my prismatic cells since April 2016 mounted in the front compartment of the 5th wheel, living off of the system in signature. Over 30k miles of highway and off road conditions (NF, BLM, State lands) and no problems so far.
Thank you for the prompt reply.
 

Dzl

Unoffical Forum Librarian
Staff member
Moderator
In terms of size, in the marine world best practice is </= 200ah with </= 100ah being ideal. As Sojourner states, mechanical failures have generally been cells of 400Ah and up. Up to you to decide how closely that use-case relates to yours.

In terms of casing type. Bearing in mind that there are usually exceptions to any generalized rule, the Nylon (plastic) cased cells, are generally regarded as more physically robust and durable than the majority of aluminum cased cells. Part of this has to do with the durability of the casing, part of this has to do with the build quality, and part of this has to do with the more robust terminals, which are supposedly actually integrated into the case structure, and beyond this are just beefier generally. The stud/bolt diameter and busbar quality are often superior as well. There is one aluminum cased cell that is considered fairly robust, that would be Frey (also known as Fortune, or Overkill Solar), there may be others but this is the one I am familiar with.

The Tradeoff with the more robust construction is somewhat less energy density (i.e. slightly larger and heavier cells for a given capacity).

For the sake of comparison here are some pictures of some of the popular Nylon Cased prismatic cells, as well as the Frey cells compared to the popular EVE aluminum cells (each image can and should be enlarged to view the terminals and build quality closeup):

CALB SE 100AhCALB CA 100AhSinopoly 100AhWinston 100AhFrey 100AhEVE 100AhEve 280Ah
s-l640.jpg3-2v100ah-lifepo4-battery-cell-8pcs-calb.jpgOut-of-the-box-768x576.jpg12v-winston-lifeypo4-battery-90aha-lithium.jpgHTB1Luhze.GF3KVjSZFmq6zqPXXar.jpg16pcs-a-set-us-eu-tax-free-new-eve-lifepo4.jpgHb39586777e1f4ebab15281490b385817c.jpg

And here is an example of a very robust installation with compression that is pretty easy to emulate. The only thing it is missing is a protective cover for the cell terminals:

LFP-200Ah.jpg

I think either aluminum or nylon cased cells can be made secure, I think that in practice, aluminum cells take more care and require more external protection compared with their nylon cased cousins . Both have their pros and cons.
 

Sojourner1

Itinerant
Just remember in a mobile environment even if you build & compress something Dzl has shown above, that needs to be secured from movement (all movement) where its being mounted. Especially in an rv that's leaving the asphalt and possibly going into rough country, I've been up some pretty rough, uneven, washboard roads. You know when you look inside the trailer and things have moved in the trailer, think of the battery location and what's being stored near them.
In this pic of the system you can see the wooden enclosure the batteries are in.
20200126_094108.jpg
RV Misc 009.JPG
Then add the generator and other misc items (depending on location). I have 2 generators from pre solar/ lfp days but one is all that gets used maybe 12x a year for a couple hours each time. Plus other misc items in that compartment.
RV Misc 016.JPG
 
  • Like
Reactions: Dzl

Ken99

New Member
Yes, its good to know the nylon case cells are that durable. I'm designing my setup initially around 8 CA180 cells for a 12 VDC, 360 aH bank similar to the first photo shown by DZL. I've picked out the Overkill 12 VDC 4S BMS since I will need reliable low temperature charging protection. The trailer already has a Progressive Dynamics PD4045LICSV power supply that supports charging Lithium batteries at 45 amps max from shore power or generator. I'm contemplating Renogy's new combination DC-to-DC/MPPT charger to facilitate charging from the tow vehicle, and provide future expansion for roof-top panels. The cells, BMS and Renogy are being bolted down in an industrial grade aluminum tool box that will tuck nicely on the front hitch behnd the propane bottles and body of the camper. The box is no wider that the bottles, so it should be well protected from road debris. There's enough room in the box to add at least 8 more CA160's if I want to expand capacity. The rubber isolators should take a majority of the jolt out of most road bumps unless I do something stupid, which at my advanced age (mid 60's), I'm not likely to do.
 
Top