What is going on here? Just got ZKE-40

[Alkaline]

Who are you talking to?
I'm just going to assume its me.
I won't bother you again.

Sorry, I was just a groggy in the morning... I don't know how to do the things you were asking and assumed I had to buy more stuff and well I just lost it. ?

If anyone can make a write up on to do the stuff you suggested I will try it, but I don't have a clamp meter at the min, just standard volt meter.

 

[Alkaline]

Use your fan tester on that same 280K cell in your first post.

Yes I did, it was less AH of 276 AH and 892 WH so less than the ZKE but same situation higher WH than AH.

 

[Alkaline]

Here is another basen cell, well at least they are consistent, Xuba test is currently running, what a PIA that cell was impossible to charge but after much fuss and a very very slow charge I finally go it to stay at least 3.44 ish and now the test is on going.

 

[Just John]

I know these ZKE testers are getting popular. But I don't trust them yet. This is not the first time I've see them pass Wh, but under on Ah

They store all the data, you are more than welcome to read the data and perform your own calculations for watt hours, Excel is a handy tool.

I personally compared the results to two calibrated lab instruments, and don't see a problem. YMMV

 

[Just John]

Well thats why I made this thread to see if my charger is busted. But I tested 3-4 of my Luyuan cells and those grade A cells all behave this way 277-279 ish but all have over 900 WH.

I think the grade A cells have more WH for the same AH. Also the average voltage for the Luyuan matched & batched genuine cells is higher than grade than the Xuba or Basen.

JustJohn has the same tester I do and also luyuan cells I'll ask him to upload htis results, he has matched & batched from Luyuan as well.

I only have the 304AH matched and batched from Luyuan, not 280. I do have some 105 as well.

I'd have to dig through some archives to find the actual data files, but the initial batch of 304AH cells I ordered to test had the following results:

315.3​

316.3​

314.9​

314.4​

 

[Alkaline]

Xuba test, very strange not as bad as I suspected but this is the cell that is always giving me issues during charging/discharging. Not great Capacity wise.

Purchased Nov. 2020 from Xuba through Amy Wan, appx 15 or so cycles. 258 AH - 828 WH

 

[Loadtoad]

Recently,

I am thinking relying on AH is not enough to determine cell quality, so I finally ponied up the cash and bought a ZKE-40 tester and tested 1 of my Luyuan 280K cells, matched & batched genuine.

Googled all over the web and could not find the zke-40 tester. All I could find was the 20 mode. Where did you buy it?

 

[Alkaline]

https://www.amazon.com/EBC-A40L-5V40A-Battery-Tester-Capacity/dp/B098QJDRP6

cheaper on ali but shipping is same as the item plus wait, plus ali-pain .

 

[Just John]

Googled all over the web and could not find the zke-40 tester. All I could find was the 20 mode. Where did you buy it?

I bought mine here:

https://www.aliexpress.us/item/3256801785667407.html

Also available from Amazon:

https://smile.amazon.com/T-king-EBC-A40L-Current-Dischage-Capacity/dp/B08KS1NSMP/

Try googling the model number, EBC-A40L.

 

[Alkaline]

Look found another guy: https://diysolarforum.com/threads/opinions-welcome-for-newbie-lifepo4-battery.47310/

Same 279AH

now I know for a fact EVE is pushing out BS, these were supposed to be 292AH. Thats like the 5th person that has grade A unable to hit 280AH!

 

[sunshine_eggo]

Look found another guy: https://diysolarforum.com/threads/opinions-welcome-for-newbie-lifepo4-battery.47310/

Same 279AH

now I know for a fact EVE is pushing out BS, these were supposed to be 292AH. Thats like the 5th person that has grade A unable to hit 280AH!

You've been here awhile. How is any of this new to you? It's been bitched about ad nauseum.

From nearly two years ago now...

36 EVE 280 cells capacity tested

I just completed testing 36 EVE 280AH cells purchased in the Group Buy thread. Tester: https://www.aliexpress.com/item/32821857011.html Wire gauge increased to 10. Connected to cell via lugs (in other words - a high quality connection, not the alligator clip method). Amperage: 15 Temperature...

diysolarforum.com

The issue here is foolish people expecting to get premium conforming product from secondary sources at discount prices based on lies from a business culture prone to lying. I don't give a shit what one WANTS. Reality is going to slap one in the face. Buy cells at 30+% discount, get cells that fall short of the data sheet in some way.

When one doesn't get outright ripped off when ordering from China, one calls it a win. When getting 95% of spec for 30% off, one should go buy a lottery ticket because the luck gods are a'smilin.

OR one should get their wallet out and purchase through authorized distributors selling true Grade A cells rather than being deliberately gullible because one disagrees with reality.

Don't like being lied to? Don't buy from ali*.

 

[Alkaline]

Eggo,

look at this thread: https://diysolarforum.com/threads/opinions-welcome-for-newbie-lifepo4-battery.47310/

These were not grade B cells these were EVE Official cells grade A cells with the EVE's own terminals, he paid the full retail price and still getting 276-279. It would be different if they were grade B cells, then who cares, but not if they are supposed to be grade A with eve's own adapter and intact QR code made in March 2022.

 

[BradCagle]

Eggo,

look at this thread: https://diysolarforum.com/threads/opinions-welcome-for-newbie-lifepo4-battery.47310/

These were not grade B cells these were EVE Official cells grade A cells with the EVE's own terminals, he paid the full retail price and still getting 276-279. It would be different if they were grade B cells, then who cares, but not if they are supposed to be grade A with eve's own adapter and intact QR code made in March 2022.

I wonder if we get too hung up on this Ah number. Wh is much more useful, and really gives us the whole picture, and given your test results, your cells exceeded this.

Now back to the Ah rating. I wonder if these 280k cells need more load to hit that Ah number. I've seen this in some of my testing.

 

[Alkaline]

Well I also think we should start looking at WH or at least BOTH AH.

So I say for it to be a true grade A it must pass both AH and WH. If I had to pick only 1 I am leaning towards WH.

 

[740GLE]

That or EVE 280k cells are just turds no matter who you buy them from.

Focus on increasing cycle count to sacrifice capacity.

 

[740GLE]

Well I also think we should start looking at WH or at least BOTH AH.

So I say for it to be a true grade A it must pass both AH and WH. If I had to pick only 1 I am leaning towards WH.

And not to long ago to consider cells “passing” they needed to pull above nameplate ratings, today seems like they are hardly meeting nameplate without dropping current to something stupid low.

 

[Alkaline]

This is true, I have seen some insane readings 1 guy was saying wow I got 319AH, but then I asked for his WH and it was only 956WH? How does that even make any sense if the cell is rated for 966WH, this was a CATL 302 Grade B so you pass 1 but fail the other? I'm the exact opposite with my luyuan fail the AH but pass the WH.

So yeah, I think we need to re-evaluate, how we evaluate cells, only issue with this is many people do not have WH ratings, or at the very least avoid the LF280K as all other eve cells grade A at least passed both AH and WH.

 

[John Frum]

The issue here is foolish people expecting to get premium conforming product from secondary sources at discount prices based on lies from a business culture prone to lying.

If automotive grade EVE cells with test report don't pull the rated capacity there is something wrong somewhere.

I want to know where that something is.

Maybe its the test equipment.
Maybe its the test methodology.
Maybe its the cells.
Maybe its something else.

A cynical person might wonder if the B was added to the QR code because the new automotive grade cells can no longer be differentiated by capacity.

Having said that, I'm sure that there is more to automotive grade than just capacity.

 

[BradCagle]

Here is the data sheet. On page 6 it tells you how to test. Says to charge it at 0.5c, let it set for 1h, then discharge at 0.5c at 25 Celsius

Eve LF280K data sheet

This is the latest version of the Eve 280 amp hour cell. March 23, 2021

diysolarforum.com

So maybe this is the problem

 

[John Frum]

Here is the data sheet. On page 6 it tells you how to test. Says to charge it at 0.5c, let it set for 1h, then discharge at 0.5c at 25 Celsius

Eve LF280K data sheet

This is the latest version of the Eve 280 amp hour cell. March 23, 2021

diysolarforum.com

So maybe this is the problem

Maybe, but in my experience cells generally test higher with lower discharge rates.

 

[houseofancients]

That or EVE 280k cells are just turds no matter who you buy them from.

Focus on increasing cycle count to sacrifice capacity.

i think we can safely conclude the 280k since december 2021 are in general just bas cells, whatever the cause may be...
again my zke tester was compaired against really expensive lab equipment and was surprising accurate...
for those that bought the 280kś this may be a hard pill to swallow, but sometime life is just life

 

[John Frum]

surprising accurate...

How accurate?

 

[houseofancients]

How accurate?

within 1.4 Ah and 1,2 wh
must add, i did replace the alligator clips

 

[John Frum]

i think we can safely conclude the 280k since december 2021 are in general just bas cells, whatever the cause may be...

If EVE has been fudging their test reports I suspect their tier 0 customers will figure it out.
I doubt they care about us but the big customers are a different story.

 

[houseofancients]

labtester : digatron MCT-HD

5 different of my own CALB 180 cells , 3 full cycles on both testers

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