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EVE LF280K 16S JK B2A24S15P-CAN

I have just recieved 64 EVE 280K cells and tested so far 10 of them with the ZKE 40 tester. So far one was 280AH the other 9 between 260 and 270. I want to post the full results when done with all testing. But so far results look identical as what is described here.
 
Who was your seller, post screenshot and data file.

We need to start a RIOT and force EVE to respond the same way they did with the packing situation:


EVERYONE with GRADE A cells & test reports needs to post results and compare!

⚔️
 
But if they are qualified by grade A and B based on their capacity and Docan doesn't sell grade A, how do I have 3 cells above 280Ah?

I am not sure about that theory... I think there is a big variation between these models of cells and its luck of the draw.
I don't believe they are all tested...
 
Cell 1, cycle 2 - 265,6Ah

This time I replace the 6mm cables for 35mm that had only 0,005 voltage drop and the value was similar to cycle 1.

Will check the logs to understand why charger display 291Ah and discharge 265Ah

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Yeah that tester is not really giving much info.... maybe try the fan tester from amazon or something... That is quite low for grade A. Usually grade 280K tests between 276-278 AH
 
All the cells I tested had the advertised capacity, the software for the KEL103 has a bug and don't display the correct capacity it has a deviation of 1.073 but the display of the KEL103 show the right Ah.

So I came to the conclusion that Grade A cells have the capacity and energy that EVE advertises if you don't get their values test your equipment and follow their guidelines, after those if they don't have 280Ah you have grade B or second choice cells.

Also the cells with the new terminals should have close to 20-25 mOhms internal resistance, put the probes on the top of the terminal and not in the base where they were laser solder, there you get about 50 mOhms.

This is cell 4 that was charged 2 days ago and discharge processed at 19º C and got 279.95Ah - 905.78Wh
P.S. Lower voltage in the beginning of graph it's because sense clamp got loose for the first 85 seconds, cell value was 3.33V.


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None of my meters are calibrated but I compare them with the KEL103 to make sure V and A where OK
 

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Ok So this confirms it the LF280K is designed to be a 280AH / 900WH cell. I suppose they made it this way on purpose for grid storage. I will add your results to my growing list, seeing as your cells were made in October the theory this basically gets rid of the Only cells in January 2022/dec 2021 have issues.
 
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Ok So this confirms it the LF280K is designed to be a 280AH / 900WH cell. I suppose they made it this way on purpose for grid storage. I will add your results to my growing list, seeing as your cells were made in October the theory this basically gets rid of the Only cells in January 2022/dec 2021 have issues.
EVE states that a cell is fresh in the first 28 days and should retain a capacity of 96%.

Comparing the production date with when I receive the cells my 105 and 280 had 8 to 10 weeks difference, I assume it's the time necessary to enter in production line plus shipping.

KNon accept pre orders for less 10€ each Cell with this time https://eu.nkon.nl/rechargeable/lif...80-prismatic-280ah-280a-lifepo4-preorder.html

I had a quote form EVE factory with the same time.

Probably the cells you refer don't have issues, we use cheap testing hardware so we can't expect accurate results, for the price 30-60€ they are very good even my KEL103 is not an calibrated device so not profissional lab grade.

The important is that we use our hardware wisely and has our personal reference, 5% diference it's not important.

Don't accept my values and others has true, use your own, unfortunately those days the control quality is made by customers, for me makes no sense to buy and Electronic Load to test equipment and the software give the wrong results but this happen on a daily base :(
 
Cell 5 also with 280Ah by mistake I close the program before export log and lost Wh
 

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Delphonis

The 304 behave differently it keeps capacity well above spec even after manufacture date.

280N cell did the same. I Think Eve changed something just for the lf280K.

Many people here have 315 ah rating with the lf305 and used to fer 290+ with the 280N.
 
Delphonis

The 304 behave differently it keeps capacity well above spec even after manufacture date.

280N cell did the same. I Think Eve changed something just for the lf280K.

Many people here have 315 ah rating with the lf305 and used to fer 290+ with the 280N.

It's because of chemistry, LF280K has lower C but more stable capacity over time and has the double of cycles, for what I read the other LF has more capacity but loose it faster.
 
It's because of chemistry, LF280K has lower C but more stable capacity over time and has the double of cycles, for what I read the other LF has more capacity but loose it faster.

Yes I think this is true, its not like the other cells EVE has made everyone selling grade A 280K is getting between 276-280AH and 900-905WH so this is what people should expect.

The EVE test report is probably causing more problems than anything else because people are use to the previous chemistries.

Sadly I don't think average person is going to care, instead they will say, HAHA my grade B brand X cell makes more AH than your over priced grade A 280k...:oops:
 
If we do the math and what eve say is correct over time the K will worth the investment.

Today I put battery 3 in production and very happy for now 0.003 deviation.
I solder balance cables to the bus bars... n° 7 it's my fault when check torque skip this cell and it was only hand tight.

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I suppose I'll throw my LF280K experience so far in there for reference. I bought 16 cells from Alibaba from Shenzhen Qishou Technology Limited because they have US stock. I received them in about 7 days from the day they made the labels and 9 days total. I got 16 of the US stock LF280K and hooked them up to a JK BMS. I charged them up to 56v (3.5v) and let them balance. Did a capacity test using a smart shunt from 56v (3.5v) until my lowest cell got near 2.5v and stopped it. I got 278.9ah from the pack. It wasn't fully charged to 2.65v per so I think if I had it would have gotten right around 280ah. Here is some pics below.
 

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I got 278.9ah from the pack. It wasn't fully charged to 2.65v per so I think if I had it would have gotten right around 280ah. Here is some pics below.
Good to find someone happy with is cells.
Just in case did you check the shunt voltage and current with a multimeter, this is only for your future reference.
 
I suppose I'll throw my LF280K experience so far in there for reference. I bought 16 cells from Alibaba from Shenzhen Qishou Technology Limited because they have US stock. I received them in about 7 days from the day they made the labels and 9 days total. I got 16 of the US stock LF280K and hooked them up to a JK BMS. I charged them up to 56v (3.5v) and let them balance. Did a capacity test using a smart shunt from 56v (3.5v) until my lowest cell got near 2.5v and stopped it. I got 278.9ah from the pack. It wasn't fully charged to 2.65v per so I think if I had it would have gotten right around 280ah. Here is some pics below.

Nice result, did your shunt happen to give you the watt hour rating for your pack?
 
For the heck of it... these are my Docan batteries. All Eve-LF280K testing using ZKE A40L. Charge 40A to 3.65v @ 5A, wait 1hr, discharge 40A to 2.5v. Voltage refers to what the ZKE read before loading the test file. Regardless of data, I'm using 3 JK BMSs, and they have been working absolutely fine to power my garage. BMS shows 212 days uptime. I'm fortunate enough to have plenty of solar that getting every last Ah is really critical for my application, although "getting what you paid for" would certainly be nice. I don't know why the big variance. Is it the tester, or the batteries??

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