Replacing 272Ah with 280AH

JDTravels

Solar Enthusiast
Need some advice...
I purchased 16 Lishen 272AH cells from Xuba. I placed them in 2 24V packs. I noticed that one of the cells is swelling. Xuba does not have any Lishen cells but does have an EVE 280AH cell in stock for a replacement. They are almost exactly the same in size so no issues there. My question is if I can use the 280AH cell in the pack or will it cause problems down the road. Daly Smart BMS, one on each pack.

Thanks
Jim
 

Tuscumbia

Solar Enthusiast
I think if the EVE cell has at least as much capacity as the lishen cells and the same inner resitance, you can exchange it. If the inner resistance is to far away from the lishen cells, the one cell will charge and discharge faster or slower than the others and the balancer may be not be able to balance it. Lishen 272 cells have 0.12 mOhm +/- 0.05 mOhm IR. Which IR have the EVE cells?
 

Tuscumbia

Solar Enthusiast
Thats to much difference for my understanding. I think your pack comes out of balance with that one EVE cell. I would try to buy a Lishen with the same specs at a different seller.

Michael
 

Tuscumbia

Solar Enthusiast
Maybe Basen has more Lishen cells. I received mine 2 days ago and test them at the moment (see Lishen 272 thread). I´m not sure if I buy from Basen again because they wrapped the cells with PVC by themselves because time problems in the Lishen Factory what I can`t believe. Capacity test from the first cell I tested was good (293 Ah). One cell has a bad terminal. One cell is from a different charge because of the vent window (blueish). I contacted Emily from Basen 2 days ago but no reaction till today.
 

JDTravels

Solar Enthusiast
Tuscumbia- Thanks for the heads up about Basen. ArthurEld- I am looking at other places to get a Lishen cell...

Thanks guys
 

HRTKD

Boondocker
How much did the cell swell? Has the cell's capacity diminished? What does the Daly BMS report about this cell?

How did you notice the swelling? This is a loaded question because if the cell pack was in a properly configured compression fixture, I don't think you would be able to tell there was any swelling.
 

cinergi

1.21 Jigawatts
Why does everyone think that in a no-parallel battery (e.g. 16s) that differences in IR mean anything? All electrons must flow through the circuit. Differences in IR mean nothing. Charge/discharge *efficiency* (how much is lost to heat) does matter and that could be a factor. I don't think we can accurately answer the question. I suspect you'd be OK, but I wouldn't bet on it. I'm actually going to try swapping out 2 of my EVEs with Lishen's, which will answer the question definitively.

Also, IIRC, the spec sheet says don't mix cell brands.
 

JDTravels

Solar Enthusiast
Thanks all for the feedback. Xuba came back and said that they do have a few Lishens left. I am getting a total of 4 sent... couple spares this time. I I am building the rv system with 2 packs and 2 BMS...glad I did now. At least we would still be in business if this happens while we are on the road.
 

smoothJoey

Scary!
Thanks all for the feedback. Xuba came back and said that they do have a few Lishens left. I am getting a total of 4 sent... couple spares this time. I I am building the rv system with 2 packs and 2 BMS...glad I did now. At least we would still be in business if this happens while we are on the road.
Will you test the cells to see which one is the closest match?
 

Mike Jordan

Solar Addict
I don't know enough to know whether adding another branded cell is a good idea in this size/style of cell. But I have built 18650 batts with cells with IR values that are much further apart. Does a larger cell make the IR disparity better or worse?
 

HRTKD

Boondocker
I don't know enough to know whether adding another branded cell is a good idea in this size/style of cell. But I have built 18650 batts with cells with IR values that are much further apart. Does a larger cell make the IR disparity better or worse?

My guess is that it makes it a lot worse.
 

cinergi

1.21 Jigawatts
An 18650 has a higher IR because there's only one tab at each end of the roll. That's why there's a huge advantage to these rectangular prismatics - there's a tab at every winding which means the electrons only have to travel, at most, about the height of the cell. So a larger cell does not really equate to higher IR in the prismatic world. It definitely does in the cylindrical world unless you use the new Tesla "tabless" cells.
 
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