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Are we all getting GRADE B cells??

sure, but do keep in mind this will essentially double the price..
so it's all in the eye of the beholder
EV grade are 1/3 more not 2x. Cheapest grade B right now is docan 600 + shipping (60 from houston warehouse) = 660
Cheapest EV grade is Luyuan 148 + shipping (which is about 170) = 762 (but if buying form alibaba you'll have sales tax and fees for most states so meh about 80 to cover it or so)
So worst case its about 22% more, if your state doesn't have taxes then its only 15% more.
the only thing with luyuan is its a 90 day wait.
 
EV grade are 1/3 more not 2x. Cheapest grade B right now is docan 600 + shipping (60 from houston warehouse) = 660
Cheapest EV grade is Luyuan 148 + shipping (which is about 170) = 762 (but if buying form alibaba you'll have sales tax and fees for most states so meh about 80 to cover it or so)
So worst case its about 22% more, if your state doesn't have taxes then its only 15% more.
the only thing with luyuan is its a 90 day wait.
Actually I am told they are less than half the price of new EV cells.
Somebody had posted the current prices for EV batteries in China. Now compare that to the price that the little guys buy the B cells for at auction and I hear that it is less than half of the price of new batteries.
 
EV grade are 1/3 more not 2x. Cheapest grade B right now is docan 600 + shipping (60 from houston warehouse) = 660
Cheapest EV grade is Luyuan 148 + shipping (which is about 170) = 762 (but if buying form alibaba you'll have sales tax and fees for most states so meh about 80 to cover it or so)
So worst case its about 22% more, if your state doesn't have taxes then its only 15% more.
the only thing with luyuan is its a 90 day wait.
again, you're blasting docan.
this is the response i got from CATL regarding their grading :

the battery standard of CATL 302AH is in line with the automotive level, but for the general consumer market, it can only meet the energy storage level.
level
A0 = automotive grade
A01= Professional energy storage level
A02= Residential energy storage level
Are you currently looking for a product to be used in a normal car?
If it is only used for conventional energy storage, it is recommended to use the A01 or A02 level


so you claims of grade b are merritless, and mainly out to hurt them as a business
 
this is the response i got from CATL regarding their grading :

the battery standard of CATL 302AH is in line with the automotive level, but for the general consumer market, it can only meet the energy storage level.
level
A0 = automotive grade
A01= Professional energy storage level
A02= Residential energy storage level
Are you currently looking for a product to be used in a normal car?
If it is only used for conventional energy storage, it is recommended to use the A01 or A02 level
cool!! thanks for this. very interesting.

wonder what A0/A01/A02 map to in terms of specific performance parameters... ?
 
EV grade are 1/3 more not 2x. Cheapest grade B right now is docan 600 + shipping (60 from houston warehouse) = 660
Cheapest EV grade is Luyuan 148 + shipping (which is about 170) = 762 (but if buying form alibaba you'll have sales tax and fees for most states so meh about 80 to cover it or so)
So worst case its about 22% more, if your state doesn't have taxes then its only 15% more.
the only thing with luyuan is its a 90 day wait.

Amy will also let you do a bank transfer and skip the sales tax and credit card fees. My credit union charges nothing for international bank transfers.
I do understand that people who haven't made a significant number of prior orders with Amy will prefer to pay the extra fees, but the option is available. Yes, the wait sucks.
 
again, you're blasting docan.

I didn't see any mention of Docan except as a pricing example. Every vendor claiming grade A cells is lying unless they have a test report. EVE has decided to do something about it. If that hurts or helps Docan, I don't see that as being any different for every other vendor that has been claiming grade A EVE cells.

this is the response i got from CATL regarding their grading :

the battery standard of CATL 302AH is in line with the automotive level, but for the general consumer market, it can only meet the energy storage level.
level
A0 = automotive grade
A01= Professional energy storage level
A02= Residential energy storage level
Are you currently looking for a product to be used in a normal car?
If it is only used for conventional energy storage, it is recommended to use the A01 or A02 level


so you claims of grade b are merritless, and mainly out to hurt them as a business

I can say with EVE cells, you are either buying grade A(utomotive) cells or grade F(ailed automotive testing) cells.
If they are from EVE and don't come with a test report, they aren't grade A, you can call it whatever grade you want, but they are not grade A.

CATL testing and grading process I have no knowledge of, however the A(utomotive) testing/grade is defined by the Chinese government. Apparently they consider car fires a bad thing. The subject however is cells marked as "B" by the manufacturer, that apparently does not include CATL.

Personally, I prefer to buy the grade A cells, they aren't that much more expensive. People are free to spend their money however they wish, with any vendor they wish, not everything is about Docan.
 
again, you're blasting docan.
this is the response i got from CATL regarding their grading :

the battery standard of CATL 302AH is in line with the automotive level, but for the general consumer market, it can only meet the energy storage level.
level
A0 = automotive grade
A01= Professional energy storage level
A02= Residential energy storage level
Are you currently looking for a product to be used in a normal car?
If it is only used for conventional energy storage, it is recommended to use the A01 or A02 level


so you claims of grade b are merritless, and mainly out to hurt them as a business


Where are you getting this information?

Since you seem to know everything about Docan, are they now going to carry CATL cells only because the eve cells will have a B on the qr code?
 
I checked my "Grade A" EVE Cells from Basen:
AH seems ok. So I went for the dimension check.
I lay the cells flat on the long side and stacked them 8 high.
Very small gaps, about a paper thin, are noticeable between cells.
Is this what you call failed Grade A then?
Or is it IR? Old EVE 280N cells are rated 0.15mOhms; the newer 280Ks are 0.21mOhms.
 
I don't know all the details on what test they do but the test includes various things like:

X-ray test
Hi-Pot test
Dimensional test
Appearance test
Capacity test
IR Test

They have machines that do all of these. All I know and has been confirmed is that the only ones that pass get the test report, the ones that don't they sell off in bulk to wholesallers in auctions.

I talked with Luyuan's Amy wan and she said basically all the money is in grade B cells as profit margin on grade A is very bad despite costing more.

According to lampard Li from EVE they might just stop even offering grade A cells all together and only focus on selling to OEMs, I talked with them as well and they said the DIY channel is full of issues and surprisingly only USA and UK want the grade B but countries like Turkey, India, Saudia arabaia only want grade A.

I asked Amy from luyuan on why she wont sell CATL and Ganfeng and she told me they don't want her business and to get lost. They don't waste time with small hobby sellers ? the CATL cells you see on ali are all grade B. I don't know about Ganfeng but I think you have to buy 10,000 cells for them to even consider doing business, supposedly these are very good cells.

Either way, we may have no choice and eventually go back to just having grade B because we all are (like 95%) looking for champaign on a beer budget and most of these big companies are not going to put up with our foolishness.
 
A(utomotive) testing/grade is defined by the Chinese government. Apparently they consider car fires a bad thing.
yea! pretty cool.
China MIIT regulations approved in May 2020 will require EVs to inhibit any fire or explosion within five minutes after a thermal runaway incident happens in battery cells. NCM chemistries will require Mitigation systems: mica sheet, aerogel, steel beams, other options.
https://diysolarforum.com/threads/l...it-regulations-affecting-auto-industry.25549/
 
I have a hard time imaging that a huge battery maker is bothering to categorize batteries as A0, A01, A02 etc.
These companies exist to make Automotive cells and they either pass or they don't. If they Don't pass then I would suspect they just want to get rid of them ASAP.

It is probably the buyers that are now coming up with all these different grading levels.
In order to survive in China you have to constantly adapt. They got away with a year or more of selling the cells as A and A+ with 6000, 7000 and even 10,000 cycles. The Jig is up and now they are adapting by changing the message. The message will never be that they are selling you B Cells or Used Cells, it will be anything else but never an admission of that.

I don't even know why they bother. I think Sig Solar got that partly right when they said it was a 5 year warranty on the Eg4. If you can get 5 years or 2500 Cycles for half the price your still getting a worthwhile deal.
 
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Where are you getting this information?

Since you seem to know everything about Docan, are they now going to carry CATL cells only because the eve cells will have a B on the qr code?
got my information directly from CATL.

did not get my info from docan, and to my knowledge they dont carry CATL
 
The entire Grade A, Grade B etc nomenclature is imprecise and not very useful IMO.
We just kind of wind up with a situation where any cell that doesn't fail basic tests or display visual imperfections gets marketed and traded as "Grade A."

I just want to buy cells which are newly manufactured, unused, and which meet the manufacturers specifications in every way, while lacking any type of defect.
Yes,the new battery will definitely perform a lot better than a used one and be safer, but the price will be slightly higher and I would prefer to use such a battery.
 
The entire Grade A, Grade B etc nomenclature is imprecise and not very useful IMO.
We just kind of wind up with a situation where any cell that doesn't fail basic tests or display visual imperfections gets marketed and traded as "Grade A."

I just want to buy cells which are newly manufactured, unused, and which meet the manufacturers specifications in every way, while lacking any type of defect.
Buy Automotive grade Cells from SKF. They are Grade A(utomotine) prismatic LiFePO4 cells from EV, With all markings and Test data sheets if requested.
 
Recent SFK testing videos showing “bad cells” makes me wonder how much they just want to slander cells without papers as “low quality” cells not worth your money.

I’m not knocking SFK products but, more of the black or white, any cell “without papers” or non EV cells are junk.
 
I still haven’t figured out what is wrong with the grade B cells I got from Docan, capacity is good, no runners. Here is a shot of the BMS after a parallel top balance, discharge to 11 volts, full charge, discharge to about 30%. They are perfectly balanced.

View attachment 101834
Was that set of cells just good luck, or do you believe that all grade B cells from Docan will perform this way ?
 
Was that set of cells just good luck, or do you believe that all grade B cells from Docan will perform this way ?
This is the fifth of eight 280ah batteries from two different orders, this is the best so far but all of them have been between .000 and .006. These are LF280N not the newer LF280K.
 

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Amy will also let you do a bank transfer and skip the sales tax and credit card fees. My credit union charges nothing for international bank transfers.
I do understand that people who haven't made a significant number of prior orders with Amy will prefer to pay the extra fees, but the option is available. Yes, the wait sucks.

The issue is when the Battery seller ships them and somewhere between their back dock and YOUR front porch something goes wrong ... there are literally 20 hands involved and often times things get damaged or disappear then if you do NOT use a credit card you are out of luck....

Alibaba and AliExpress will typically (99.9%) of the time side in favour of the seller -- not you ...

You don't use a CC and FedEx messes up one of the boxes -- well YOU are going to be trying to get that all unscrewed for months with trying to get FEDEX to talk to the shipper who suddenly is on holiday for the next 2 months ...

IF you DO use a credit card and FEDEX messes up -- or the battery doesn't show up -- then you call your CC and the money is back in your account that moment ...
 
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