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Beware of Docan Technologies (Issue Resolved)

So if you buy the EVE cell with the welded on terminals done by EVE as shown in the picture, you will more likely be getting grade 'A" cell since not likely that EVE will weld the terminals on to the cell if the cell fails the test? If I build another battery pack I may be looking into buying them, I kind of like the terminals.

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I would think it VERY likely. Anyone can weld terminals on, but as far as I know, only EVE is currently using that style. I doubt EVE would weld them if they were not going to be sold for full price.
 
I should have said that style of terminals, I think it is pretty safe to buy these EVE cells with this terminal style..
 
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For electric vehicle use, wrapping cells interferes with thermal transfer ability. Since most people don't want an electric vehicle that takes more than an hour to charge when traveling long distances, thermal transfer and thermal management makes for different designs than for solar energy storage. The unwrapped cells with no studs is exactly how the cells come off the production line after layer formation and testing. EVE can and will wrap cells, and weld on terminals, but you pay extra for that. Cells that don't meet the EV specs and are thus sold to a different market would almost never be wrapped or have terminals or holes. Nothing nefarious here, they are simply wrapping the "failed EV grade A" cells and getting them in a condition where they a more marketable commodity. The secondary market uses the same material to wrap the cells, but you can actually tell the difference in workmanship when you compare side by side with EVE wrapped cells, and the "genuine grade A" cells that failed and are wrapped by vendors. The majority of "not grade A" cells sold as "genuine new grade A" are an excellent value, but at high C rates they will fail testing. Most people don't use high C rates for solar energy storage. The real problem is the vendors that are selling used cells as "genuine new grade A", probably thinking that people are buying grade B, they might as well make a tidy profit by selling former genuine grade A that are end of life as new.

If vendors would accurately label cells, it would help. It won't completely solve the problem, since EV pulls will still have grade A bar codes, just end of life due to capacity degradation. I disagree that the fraudulent adverting and deception used is a cultural thing, most Chinese are acutely aware of the fact that it happens. Indeed their purchase of things like baby formula from overseas sources reveals their distrust of any claims of purity and "fit for purpose" claims by local vendors. Vendors know what they are doing, and do it because there is profit to be made, and little chance of their being held accountable.

I don't think C rates are the only thing with Grade B cells, there could be a multitude of things, my Xuba after 2 years are starting to suck, I will do a capacity test but I doubt I get more than 240 AH at just a pathetic .2C discharge rate.

The Chinese can pull this crap far easier on the west because of no consequences. If they try to pull some of the bs in China the CCP can and will break there back or make them disappear.
 
The Chinese can pull this crap far easier on the west because of no consequences. If they try to pull some of the bs in China the CCP can and will break there back or make them disappear.
Of course, because they are creating foregn currency so the CCP does not care what their ethics are as far as the West is concerned. Surprisingly it is Capitalism at its worst. Those are the risk management elements that every buyer needs to be aware of when they get a good deal from China.
 
Of course, because they are creating foregn currency so the CCP does not care what their ethics are as far as the West is concerned. Surprisingly it is Capitalism at its worst. Those are the risk management elements that every buyer needs to be aware of when they get a good deal from China.
Part of their global plan to dominate the economy. The Government is behind it and subsidizes all of it.
 
I don't think C rates are the only thing with Grade B cells, there could be a multitude of things, my Xuba after 2 years are starting to suck, I will do a capacity test but I doubt I get more than 240 AH at just a pathetic .2C discharge rate.

The Chinese can pull this crap far easier on the west because of no consequences. If they try to pull some of the bs in China the CCP can and will break there back or make them disappear.

I have some Xuba cells as well, they were extremely well priced, but as you say, even low C rates are problematic. This is the reason I've been purchasing the much more expensive A grade EV cells with test reports since then. For me, it's peace of mind, I buy them mainly because of safety reasons, not capacity (the A grade cells). I do however understand why people purchase the more reasonably priced alternatives. I also have no desire to support vendors that I know are lying to me. There are lots of reasons cells could wind up on the secondary market at cut rate prices, and a lot of them are quite acceptable as solar energy storage. The problem is, some of the reasons could be quite dangerous as well, and it's just too much of a crapshoot for me. Especially when you already know the vendor is not telling the truth.
 
Part of their global plan to dominate the economy. The Government is behind it and subsidizes all of it.
It happened once before that China dominated the world economy. 300 years ago, before the industrial revolution, China was reportedly the largest economy in the world. I say reportedly because we did not keep those statistics. I believe that to be true and, more importantly, It is taught in Chinese schools so the population believes it. Despite the authoritarian government the population has a long history of being capitalists, It may not be the kind of capitalism we are used to with our government protections. The government promises them a return to their past glory, not by war but through their inherent capitalism. Sorry for the digression. This has nothing to do with Docan.
I don't think C rates are the only thing with Grade B cells, there could be a multitude of things, my Xuba after 2 years are starting to suck, I will do a capacity test but I doubt I get more than 240 AH at just a pathetic .2C discharge rate.
I agree. I think the discharge curves may vary from cell to cell but much of that is masked by the flatness of the discharge curve. It shows up under heavy load. My 48 cell pack is from three different vendors during my buying spree in 2020. That plus the fact that I already had a high amperage BMS is why I configured my pack as 3P16S. In that way those differences will average out. The reduced capacity would only bring my cost up to $140 per kWh which is still acceptable. By the time I need a new pack I will be too old to do another DIY pack and hope that UL listed packs are available at reasonable costs.
 
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How many Docan purchasers felt they were getting Grade A cells? Shenzhen Luyuan pricing was always higher than Docan, Basen, and all the other sellers. Why did anyone think they would be getting Grade A premium cells? It wouldn't surprise me if Amy Wan saw sales fall off a cliff as the Grade B peddlers flooded the market. In the cutthroat Chinese marketplace, I imagine getting less than you paid for is far more likely than getting more than you paid. All speculation on my part. I have no lifepo4 cells nor any relationship with resellers.

Sunfunkits has a youtube video from some time ago. They demonstrate the difference between Grade A and non-Grade A cells. The Grade A cell voltage sag is much less than non-Grade A. As I recall, even a 30A load on lower grade cells would shows significant voltage sag.
 
How many Docan purchasers felt they were getting Grade A cells? Shenzhen Luyuan pricing was always higher than Docan, Basen, and all the other sellers. Why did anyone think they would be getting Grade A premium cells? It wouldn't surprise me if Amy Wan saw sales fall off a cliff as the Grade B peddlers flooded the market. In the cutthroat Chinese marketplace, I imagine getting less than you paid for is far more likely than getting more than you paid. All speculation on my part. I have no lifepo4 cells nor any relationship with resellers.

Sunfunkits has a youtube video from some time ago. They demonstrate the difference between Grade A and non-Grade A cells. The Grade A cell voltage sag is much less than non-Grade A. As I recall, even a 30A load on lower grade cells would shows significant voltage sag.
again, it still hasnt been proven they are not grade a cells.

seen a lot of generalisation,suspence, speculation and nonsense in this topic, and eve's new QR codes, but absolutely nothing specifically about cells sold by Docan.
sure there was a member claiming bloated cells, yet provide no evidence, and had satifactory solution provided to him.

so far lots of non specific blahblah
 
again, it still hasnt been proven they are not grade a cells.
Agreed. i saw one description that called them Automotive Grade cells that failed a test.
That is good enough for me, since I do not need to use them like I would use them in an EV. So far going on two years they still work for me.
 
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Neither www.docanpower.com nor www.powerwholesale.net label the Eve cells as Grade A. Who at Docan is promising Grade A, currently? Have a feeling the days of promoting Grade A cells is no longer.
The have a banner on there site claiming CATL 280 grade A in stock, how much you want a bet that it is isn't.

I get emails from them all the time, let me dig one up Ohh yeah Memorial Day email "Defend our country" Grade A 280K, just whose country are they trying to defend?

Also just literally yesteraday from "Lilly" at docan.
 

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Grade A-B-C don’t know don’t really care, I have purchased 28 LF280N cells from Jenny Wu at Docan. Both purchases went great, I had cells to my door in five and seven working days from ordering, cells arrived at the same voltage about 30% charged and in perfect condition with QR code’s intact.

Top balanced the cells and they have been working great for a year and a half, no balancing issues they stay within .015 top to bottom. I am ordering another 16 cells soon.
 

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I just ordered some batteries from Jenny. She said they don’t have those style connectors.
Which one did you order? You want the Terminal stud? like this?
 
No one is arguing about the value of grade B cells, the issue is sellers claiming grade A when they are not. Even now that eve is marking them as grade B they are still the same, sellers like Dongan LIghting are stiring up tales on how its just a different supply but is the same cell.

I won't argue that the best overall strategy is still buy more than you need for grade B, e.g. if you need 16 cells then buy 18-19 and select the top 16 out of that lot. You'll be ahead vs grade A/EV cells.

But there is no excuse for these sellers to keep claiming they have Grade A cells when they don't it makes the real grade A sellers look like they are looting, recently I found this video:


This guy seems like a nice chap and I'm sure his intentions are good, but bundling Jenny Wu together with Amy from Luyuan is complete BS IMO, Ray would never know the difference unless he had a true EV cell vs Grade B cell. Yet Jenny Wu has no problem proclaiming her stuff is the same or better than Luyuan.


If you guys keep excusing this behavior the Chinese will keep screwing over the market and maintain the status quo of confusion.
 
Which one did you order? You want the Terminal stud? like this?
Yea that’s the one Jenny told me to get. She said those were the new ones.EVE LF280K 3.2V Lifepo4 cell. That’s the part number from the invoice. Thanks for looking out. Appreciate it.
 
I had a similar experience with Docan. But I don't complain as I got pretty good LiFePo4 cells.

I directly ordered and paid (both cells and shipping) 4 x CATL 100Ah old-style prismatic cells with a plastic enclosure. These happened to be out of stock. I was offered a replacement - EVE LF105 cells instead of what I ordered. If I recall correctly these were even more expensive than the CATLs. But this was all communicated prior to shipping the order. In the end, I was pretty satisfied with what I got.

These are the same cells I used for the 12V power bank I built. There is a topic on that here in the forum.
 
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