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Xuba Electronics: DEAL - 280AH LiFePo4 cells. Purchase & Review

Carly said:
Hopefully they don't send you 280AH cells!
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I wouldn't mind that ?. Amy did confirm the 8kg weight (4x2kg) when she quoted the shipping costs. The 280Ah cells should weigh 5.2kg each, so ~21kg. I expect at least the shipping company would notice it.
 
Plot-twist. The video of earlier is actually from another customer ? I guess I’m not getting those 280Ah cells after all ?‍♂️
 
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Steve_S said:
A word of wisdom / experience. Don't attach battery cable to the cell terminals as such. It's much more prudent to run a (+) & (-) lead to Battery Terminals from the cells and then attach your cabling to the terminals with a fuse of course on the (+) terminal.

Terminal such as these but there are many varieties to suit various needs.
7110.jpg
Military-grade.png


@andruby She has always provided photo's of the cells you are getting & a little video of the voltage tests. I had suggested that she put a Name Card with them when taking the pics / vid so people know it's theirs that they are seeing.
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Can you give a simple example of what you mean by this?

I really want to try and build my own pack for my boat, but a bit nervous about making fatal errors, especially due to language based misinterpretations...
 
Patrick-B said:
Can you give a simple example of what you mean by this?

I really want to try and build my own pack for my boat, but a bit nervous about making fatal errors, especially due to language based misinterpretations...
Click to expand...
It is unwise to attach battery cables directly to an LFP cell as battery cables can move and the "posts" on LFP cells are not like Lead Batteries, the posts are weaker and can be damaged, damaging the cell. Good Practices are to run a cable from your cells (-) & (+) to fixed "terminals" as shown above and then attach your battery cables to them. The terminals of course have to be solidly affixed to the case or housing so they do not move for the battery pack.
 
Patrick-B said:
Can you give a simple example of what you mean by this?

I really want to try and build my own pack for my boat, but a bit nervous about making fatal errors, especially due to language based misinterpretations...
Click to expand...
Patrick, check out Wills video where he built a $555 battery. He used terminal posts to connect his cells/BMS to the outside world. That way any cable strain/vibration from the outside cables only goes to the terminals of the "battery" and not to the top of your precious cells.

Here is what Will used.
 
Steve_S said:
It is unwise to attach battery cables directly to an LFP cell as battery cables can move and the "posts" on LFP cells are not like Lead Batteries, the posts are weaker and can be damaged, damaging the cell. Good Practices are to run a cable from your cells (-) & (+) to fixed "terminals" as shown above and then attach your battery cables to them. The terminals of course have to be solidly affixed to the case or housing so they do not move for the battery pack.
Click to expand...

So just mount terminals on my batterycase, which connect to consumers?(thinking about using plywood for it. Drill a hole and use bolts to fixe them. No isolation on the wood around? Simple as that?)
 
And i read a lot about everyone balancing and testing the cells. Offcourse i got the tools to measure the V on each cell, but that is as far as my equipment goes. If all cells are the same, i can just start connecting?
And what do i do if they aren't?
 
Professor Will is the young man who opened the forum and does all the videos for us.. Of course just kidding about the Professor title but give him another couple years he will probably be there :)
 
Patrick-B said:
And i read a lot about everyone balancing and testing the cells. Offcourse i got the tools to measure the V on each cell, but that is as far as my equipment goes. If all cells are the same, i can just start connecting?
And what do i do if they aren't?
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Common wisdom is to connect all the cells in parallel and let them all come to the exact same voltage. Either passively or actively. Whether you want to bottom balance or top balance is up to you. I'm not going to repeat what is covered in many long threads here.
Here is one thread on the subject......

https://diysolarforum.com/threads/lifepo4-top-balancing-equipment-recommendations.4118/#post-44231
 
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THE CELLS ARRIVED ! \\YAY//

Everything arrived in "perfect" condition. Not a mark or scratch and nothing to note at all.
NO DOUBT That these are Grade-A, NEW cells !
All cells wrapped individually, double boxed with foam between the boxes too.
Quite an effort to unpack them ! Well done packing.

ATM, they have been sitting in the deep cold for days, they will have to thaw thoroughly before I can do anything. (better safe than sorry eh) and my Adjustable 3-14V 50A charger has yet to arrive as well, although it is in transit. I want to test each cell, full discharge, full charge (3.65V) & another full discharge (to 2.5v), then after pack assembly I may do another run for "Pack Capacity" but I'll have to decide on that, when I reach that point.

NOTES:
Screws provided:
M6 with large head, 10mm long thread. TOO LONG ! The tapped holes in the cells are only 7mm deep, so washers are NESCESSARY!
Bus Bars:
These are odd but ok. Pure Copper, 15mm wide X 90mm long, 2mm thick. I consider these to be "bare minimum" for cells with this capacity. Doubling them up would also eliminate need for extra washers. NB: I will have to make my own Bridging Bars (2) as I am building "Square Packs" and the ones supplied are too short to cross over between "sides". see image below.

24v-8s-square-pack-jpg.7910

As I will be building BOXES from plywood to house the "packs" I had to wait for them to arrive for proper measurements. In the above configuration the cell pack dimensions are as follows: 13-3/4" wide, 11-1/2" deep. 9" High (provides 5/8" clearance above screw head).


PHOTO's of the goodies:
My-280-cells.jpg

My-busbars-N-bolts.jpg

The 180W Tester I will be using:
My-180W-tester.jpg
LINK FOR TESTER: (the Tall one is the 180W unit, the flat one is 150W unit.

Hope this info helps potential buyers and those pondering options.
 
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Steve_S said:
THE CELLS ARRIVED ! \\YAY//

Everything arrived in "perfect" condition. Not a mark or scratch and nothing to note at all.
NO DOUBT That these are Grade-A, NEW cells !
All cells wrapped individually, double boxed with foam between the boxes too.
Quite an effort to unpack them ! Well done packing.

.......big snip........



Hope this info helps potential buyers and those pondering options.
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Did you take any precautions unpacking them for Corona Virus? Disinfect them in any way?

ETA: Home Depot has #14 brass washers which have a 0.3" hole in them.
 
Sgt Raven said:
Did you take any precautions unpacking them for Corona Virus? Disinfect them in any way?
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I don't get involved in hypochondriac hyperbole. Mrs is a Doctor of Public Health teaching at the 4th top Medical University in North America, I get my info from CREDIBLE sources only thanks. I won't get into that stuff.
 
Steve_S said:
Bus Bars:
These are odd but ok. Pure Copper, 15mm wide X 90mm long, 2mm thick. I consider these to be "bare minimum" for cells with this capacity. Doubling them up would also eliminate need for extra washers. NB: I will have to make my own Bridging Bars (2) as I am building "Square Packs" and the ones supplied are too short to cross over between "sides". see image
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One thing I forgot to do was tell Amy to double up on the amount of bus bars she was sending; so that kinda sucks... Might get some copper flat stock and make my own since you think they are the bare minimum for this capacity.
 
GMB said:
One thing I forgot to do was tell Amy to double up on the amount of bus bars she was sending; so that kinda sucks... Might get some copper flat stock and make my own since you think they are the bare minimum for this capacity.
Click to expand...
They make the grade but just. In reality, it's very unlikely to exceed the amperage to the point where these bus bars would be a problem, I personally like to have "elbow room" when It comes to load tolerances. I have advised Amy of these details and she's working on the bolt lengths and the busbars. I'm sure they will change shortly.
 
Steve_S said:
They make the grade but just. In reality, it's very unlikely to exceed the amperage to the point where these bus bars would be a problem, I personally like to have "elbow room" when It comes to load tolerances. I have advised Amy of these details and she's working on the bolt lengths and the busbars. I'm sure they will change shortly.
Click to expand...
You have 10mm screws, 7mm inside the terminal, 2mm for the bus bars, then add ring terminals for the BMS. I'd rather have to add a washer, than have them be too short and not grab enough threads in the terminal.

ETA: I thought someone else said their terminals were 10mm deep?
 
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