EVE LF280K 16S JK B2A24S15P-CAN

[Delphinus]

This is another build with EVE Grade A cells, ordered from NKON.

Cells arrived in original packing of 4 cells each.



Cells from consecutive batch made 09 and 10/10/22, internal resistance 0.020 and 3,288-3,290V.

Bus bars are copper

 

[Delphinus]

Start charging 15S to 3,5V cell total 52,5V 10A

 

[Delphinus]

1S to 3,65V 20A.

When this one is full will remove one from the serial and charge until 3,65V and so on until all are charged.

Charged cells will be put in parallel until all are done and will test 2 to know capacity.

 

[Alkaline]

Very nice, what are you using to do a discharge test?

 

[Delphinus]

Very nice, what are you using to do a discharge test?

This one KEL-103 300W

 

[Alkaline]

cool, does it have some type of pc connection for data export?

 

[Delphinus]

cool, does it have some type of pc connection for data export?

It has USB, RJ45 and RS232.

This is the discharge of first cell and I'm saving log to import in excel, still 100Ah left, my config and result are in the lower right.


With Test Controller we can create graph but until now I don't know how to use it, probably I have to use only one program at time and not both.

http://lygte-info.dk/project/TestControllerIntro UK.html

 

[Alkaline]

This is great! Looks like a professional tool, many of us slappies have fan testers and or the zke-40 so its nice to see someone with some pro equipment.?

 

[Delphinus]

All cells charged and first cell discharged.

The value of 3.5V for each serial cell was too optimistic, 1 cell arrived to 3,7V and the other to 3,8V both were from day 9 so probably the ones that measure 3,290V and had an higher storage capacity.

This first cell measure 266,3Ah, only used 6mm cables that lose 20W/h divided by 3.2V give 6,25Ah so total will be 272,55Ah, don't know if this is normal my LF105 measure total capacity with same conditions.

 

[Alkaline]

I'm not sure, are you saying you only measured 272 AH?? I hope that's not correct, maybe your settings are not right? Many of us are using the ZKE-40 or a basic amazon fan tester;

https://www.amazon.com/150W-Electronic-Adjustment-Constant-Discharge/dp/B099226TLF

https://www.amazon.com/Battery-Electronic-Discharge-Capacity-Termination/dp/B0B31GVNTD/

 

[Alkaline]

Do you have the WH for your test?

 

[Delphinus]

I'm not sure, are you saying you only measured 272 AH?? I hope that's not correct, maybe your settings are not right? Many of us are using the ZKE-40 or a basic amazon fan tester;

https://www.amazon.com/150W-Electronic-Adjustment-Constant-Discharge/dp/B099226TLF

https://www.amazon.com/Battery-Electronic-Discharge-Capacity-Termination/dp/B0B31GVNTD/

I also have a basic tester but measure higher current than it should so Ah are not to trust.

I will test 3 cells, if they give a lower value I will use thicker cables and do another cycle and check calibration.

 

[Alkaline]

Please post the screenshot and include both the AH and WH.

Thanks,

I will pm you info... I was hoping they had fixed the 280K but now I think it is not good.

 

[Delphinus]

Please post the screenshot and include both the AH and WH.

Thanks,

I will pm you info... I was hoping they had fixed the 280K but now I think it is not got good.

This is cell 2, I got 264.9Ah, I don't have the Wh but if we multiply by 3.2V the result will be 847,68 Wh

Let's wait for an expert comment, those are my first LF280K so I don't know much about them if I'm not mistaken I read somewhere they will give lower Ah compared to the LF280 but the value will be stable thru the life of the cell, the LF280 will give more Ah but it will drop with cycles.

 

[gonmag8]

That is pretty common on the eve LF280k unfortunately.
Here are my test results (discharge only to 2.6v but that doesn't make much difference)

 

[Alkaline]

gonmag8 those are grade A or Grade B? Did you get a test report, what did the terminals look like?

 

[Delphinus]

First cell that had 272,55Ah just charge 291.9Ah according to my ISDT with voltage calibrated, and my clamp meter reads 19.89A so value should be accurate, I already start to discharge the cell to see what I will get.

 

[gonmag8]

gonmag8 those are grade A or Grade B? Did you get a test report, what did the terminals look like?

Not sure I agree with the grade A/B qualification so not sure how to answer? Grade A I guess, bought brand new from Docan.
They are the ones with single m6 post on each terminal not like the ones on the picture of this post

 

[Alkaline]

Docan doesn't sell grade A, those are grade B, here are other people who have grade b Docans:

Docan 280K results, very detailed thread by basecamp, but average 263 AH and 850WH
https://diysolarforum.com/threads/poor-docan-experience-resolved.48592/#post-618121


Docan 280K Results by Ce Ce, 265 WH and 860 WH, tested a few cells but this was the average:
https://diysolarforum.com/threads/disappointing-eve-280k-results.47555/


Docan 280K results by gonmag8 265 AH & 863.5 WH:
https://diysolarforum.com/threads/disappointing-eve-280k-results.47555/post-606579

Docan 280K by atti 270Ah & unknown WH:
https://diysolarforum.com/threads/eve-lf280k-capacity-test.49961/


Basically Grade A 280K = barely makes 280AH but does do 900WH (which is above capacity is stated as 896WH, however slightly lower on AH, usually 276-278 on average)

Grade B 280K = Does not meet Ah or WH, will usually test to 260-265 AH, and about 855-860WH

So based on on those you got grade B 280K from Docan, but as you can see Grade A 280K is not something to go cheering about either...


Seems like grade B REPT280 from 18650 is doing better and grade B catl 280 from docan is strong as well (almost 295AH and 960WH).

 

[Alkaline]

Some grade A 280K test, again disappointing, for the price I would have expected much better! I'll wait to see what Delphinus gets but it seems he too has some issues

anyway:

My Results 278.4 & 901.4 WH, Luyuan Test Report said I should be getting 289.4 AH on these Matched & Batched Cells Genuine grade A:
https://diysolarforum.com/threads/what-is-going-on-here-just-got-zke-40.49076/

shane_Uk with Luyuan Genuine matched & batch results 276 AH vs the 289 Ah on the sheet; did not show WH, but I suspect it would probably be around 900 or more:
https://diysolarforum.com/threads/opinions-welcome-for-newbie-lifepo4-battery.47310/

18650batterystore.com grade A results, a person named Dena M. Says 277.7 AH (did not show WH, but again I suspect it would be around 900ish maybe 901):
https://www.18650batterystore.com/products/eve-lf280k#looxReviews


Fogstar UK grade A EVE 280, Cajocars gets 280.5 AH & 907.5 WH EVE stated Capacity was supposed to be 293.9 AH…, but still first person with a 280K to actually break the 280 barrier…but just barely
https://diysolarforum.com/threads/just-bought-16-280ah-a-grade-from-fogstar.51027/page-3#post-662021


So you can see Grade A 280K barely makes 280AH and but it makes about 900WH so barely meeting spec...