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Xuba Electronics: DEAL - 280AH LiFePo4 cells. Purchase & Review

Subjective and marketing BS. No standard, and sellers will say whatever they think will make you buy them.

I give it no weight and only go by what other people say who have already bought cells from them.
I still remember ghostwriter66 posting, they could be the ugliest batteries around, but as long as they met the specs.
They were GTG. That performance was more important than looks.
She probably has had more real world experience with LFP batteries and buying cells from China, than most posters on here.
 
She probably has had more real world experience with LFP batteries and buying cells from China, than most posters on here.
While I don't doubt that, I have my own decades of experience dealing with electronics and batteries in-general, and I can definitively say that a moment-in-time measurement of capacity is hardly a solid way to judge the long-term health of a battery. There are latent conditions that can result from mishandling/abuse that can't be immediately measured by just a capacity test but will surface later in degraded lifespan or performance over time (or premature catastrophic failure).

A pallet that is accidentally dropped several feet might be blown out as "Grade B" at a discount by the mfr because they can't be trusted anymore to be sold in good faith under their normal quality controls. So much so they might even not want the gray market seller to publically state who the original manufacturer is, encouraging rebranding. They look new and pristine, so the gray-market seller gets away with passing them off as "Grade A". They even measure full rated capacity out of the box. However, maybe a few months or a year in, you might get a nasty surprise.
 
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First I am certainly not an expert on this and my knowledge is quite limited. If you think I am misunderstanding something please bring it up, or if you are a reseller and have some wisdom to share on the subject please do.

I keep reading on this thread opinions as to whether these are A cells or B cells. Is there a standard for A and B cells, or is this a subjective evaluation. Do B cells last as long as A cells?

There is not a single standard, but it is also not a subjective evaluation. A grade and B grade cells refer to whether a cell meets the manufacturer specifications. B grade cells are cells that are out of spec in one or more areas (not all of these areas are a big deal for our relaxed application--for instance a 150Ah cell having a capacity of 147AH would not be a dealbreaker for me so long as they are matched).

Just as important (probably more important) as knowing if cells are grade B or not, is knowing why they are grade B, we don't need absolute precise perfection for our application and shouldn't count on it at the price point people are expecting to pay. Due to this and because so many resellers either misrepresent or are ignorant of the cell grade, don't get too hung up on this factor alone.

Subjective and marketing BS. No standard, and sellers will say whatever they think will make you buy them.

I give it no weight and only go by what other people say who have already bought cells from them.
I doubt this is a real designation. No one has a specification for what those letters mean. There's no standard.

I think you guys may not be 100% clear on the terms, and are misplacing your skepticism. I fully share your frustration and skepticism towards what the resellers classify as grade A or grade B. I do not trust resellers to be honest about cell grade, this is just the unfortunate reality of things.

But I think you are missing the point if you think cell grade is meaningless or just marketing BS. I believe these conclusions are based on a misunderstanding of what cell grades are supposed to mean.

As I understand it, battery cell grades are not universal industry wide standards (which seems to be what you are thinking @nebster), but I don't think its marketing BS as you are thinking @sremick. Cell grading/sorting is specific to each manufacturers specifications and QA process. Grade A cells meet all the manufacturers specifications, Grade B cells are out of spec or failed QA in one or more areas but (in theory) are still usable/suitable for sale, Grade C cells are not suitable for use/sale and should be destroyed/recycled but some manufacturers apparently don't use the Grade C designation and unfortunately include these with Grade B.

Basically A, B, C grade are shorthand for (A) meets or exceeds specs (B) does not meet specs in one or more areas but is still usable (C) unusable. Cell grade is always relative to the manufacturer specifications, not universal across manufacturers.

Further complicating things, there are at least a half dozen reasons cells can be demoted to grade B, some of these are troubling, while many are not a huge concern for our application. Resellers buy cells from manufacturers or middlemen in big batches and from what I understand rarely know the reason the cells they are buying did not make the cut. Testing and matching before sale can help mitigate some of the uncertainty, but it is my impression that most resellers only do basic testing.

These are two of the best and most straightforward videos I've found on the subject. They cover:
  • What are grade A, grade B, and grade C cells
  • How lifepo4 batteries are produced and where in the process B and C grade cells come from
  • The reasons a cell can be derated to grade B
  • How to (somewhat reliably) distinguish grade A and grade B cells
  • Some of the ways manufacturers test cells, and some of the ways you can test cells
What are grade A and grade B cells

How to distinguish grade A and grade B cells
 
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Are cells individually tested or lot tested? I know in things like Military ammunition, they are lot tested and there is a percentage where the whole lot is rejected. That doesn't mean the whole lot is bad for general use. It just didn't meet the qualifications for the Military.
 
Can anyone provide any long term reviews of these cells? I realize the thread is only 7 months old.
 
I guess my points are,

a) the binning mechanism that a manufacturer uses may not align with anyone else's simple rubric for "A, B, and C," and their quality thresholds may even vary over time;

b) the manufacturer may choose not to disclose their own reason(s) for putting cells into a particular market;

c) the reason(s) may have nothing to do with cell performance; and

d) people can just get away with saying whatever they want, at least for a while, because the supply chain is opaque, and many subtle flaws are difficult to detect at the time of purchase.

I don't think it's worth getting hung up on trying to find "grades" for the cells. A good grade probably won't mean much, and a bad grade might be fine.

I do like your videos, though. I hadn't seen them before.
 
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I would also like to point out something which should be obvious but apparently is not.

Poor handling of cells during shipping, regardless of how well packaged, can harm cells for example if the pallet was dropped several feet. Also, let us not forget the stressed out, under paid couriers who have to handle 40+ Lb boxes (4x 280 cells). Some have noted their boxes had holes, gashes or tears, so you can only imagine the rough handling they got. These are things that cannot be accounted for and even if the cells have no visible damage, internal damage is always possible and it would be near impossible to prove it.

Within the next 24-30 Months, Europe, USA, India, SouthAfrica, Australia and a few more will ALL be getting new big Lithium Battery Factories, several are also supposed to be producing LFP in various formats (cell to pack variants mostly). Once more local (regionally) productions start to happen a lot should start to change and quickly, hopefully for the better !
 
has anyone had a bad experience with the 280Ah LiFePO4 batteries?

Amy gave me a price "Product price + freight = $330.68*4+$378=$1700.72"
but i think she quoted me for Lithium Ion Batterys not LifePO4
Alibaba is a bit confusing
 
I guess my points are,

a) the binning mechanism that a manufacturer uses may not align with anyone else's simple rubric for "A, B, and C," and their quality thresholds may even vary over time;

b) the manufacturer may choose not to disclose their own reason(s) for putting cells into a particular market;

c) the reason(s) may have nothing to do with cell performance; and

d) people can just get away with saying whatever they want, at least for a while, because the supply chain is opaque, and many subtle flaws are difficult to detect at the time of purchase.

I agree with points B through D, I especially agree with point D. The main problem as I see it is the opacity of the market/supply chain from the point of view of the end user.

Cell grades are probably most useful for the manufacturer internally and the first point of sale (between manufacturer and middleman or wholesaler or whoever is next down the food chain).

Regarding point A, I think the utility of grades is for comparing to the manufacturers own parameters. So really its best to not have a generalized presumption of what grade A / grade B means, but to interpret it as "can I expect this cell to meet the parameters defined by the manufacturer listed on the datasheet".

Of course points B and D diminish the usefulness of asking resellers about cell grade since most resellers are pretty loose with the terms, and even if they do know the grade and are honest about it, they are unlikely to know the reason since grade B cells are apparently sold in big batches.

The 280Ah EVE cells are case in point. There are at least a half dozen sellers offering them on AliB. I believe the most popular seller here Xuba, has stated they are new grade A cells (someone correct me if I got this wrong), while a couple sellers selling the same cells at the same price point, have stated the EVE cells are grade A- and grade B cells (which is a logical conclusion considering they are being sold at a fraction of the cost of new grade A cells sold through official channels). You can see the tough position this puts sellers in, because people want grade A cells at grade B prices, want to believe the cells they bought are grade A, don't really understand what it means, and overemphasis the importance of this one hard to verify factor, honesty is somewhat disincentivized even though its something we crave and profess to want.

I share your frustration, that Grade A/B is too vague and too hard to verify for the small time end user and its a valid question as to whether overemphasizing this one binary distinction does more harm than good.

At the end of the day what is important is if the cells perform well enough for your specific needs, can achieve the cycle life they should, and are a good value. I think in many cases "grade B" cells are a great value for our application, just a bit more of a gamble.

this is all just my barely informed 2cents.
 
What is the width of the bus bars that Xuba is including in our orders? I want to put heat shrink tubing on the bus bars (to prevent accidents) and need to know the size of the bus bars so I know what size of heat shrink tubing to order.

For what it's worth, TEMCo published this table of heat shrink sizes and cross referenced them to wire gauge sizes. I found it very helpful and thought others might also. The entire page can be found here: Heat Shrink Data Sheet. In my opinion, the heat shrink tubing in 4' lengths is dirt cheap.

TEMCo_HeatShrink_Tubing_Sizes.JPG
 
The ones XUBA sent me (early sales) are 15mm (5/8?) wide, 2mm thick which should be suitable to 150A.
Decided to make my own up from COPPER C110 FLAT BAR ASTM-B133 0.125" x 0.750"
The width cover the cell "pad tops", thickness is 4mm and far more suitable IMO.
cuts: 4.250" length to cross from cell side to side. (when building a block pack)
cuts: 3.750". lengh to cross between 2 cells
I put Heatshrink over the centres of the bars, used 1 stainless washer per bolt and applied a very think coat of NoAlox to the "cell pads" to prevent corrosion (NOT on bolt or threads).
 
I just received mine from Xuba ; confirm 15mm wide 2MM thickness. I also ordered heat shrink for the bars, got 3/4 inch; 3 to 1 shrink.
 
Thanks Steve. It looks like heat shrink that is 3/4" in diameter (before shrinking) should work fine, even for double bus bars. I'm ordering 3/4" tubing for my 2/0 cable already so I'll give that a try.

I'm assuming that the heat shrink is 3/4" in diameter when in circle shape. If I squeeze it flat the width increases so there should be plenty of room.
 
My experience thus far: first I want to thank everyone here for sharing each of your experiences, it has helped very much. Like a lot of people I know and talk to, I am very skeptical and leary of spending my hard earned money on junk! I have a project I’m working on and want it to be of high quality, and we all know this can be challenging these days. So, surfing for a few months, reading and watching the same material and videos you all have, I finally found this forum a couple months ago. We all know that purchasing directly from the source is generally going to be cheaper, sometime a lot cheaper, so when it comes to solar, until things change, CHINA it is and Alibaba.com seems to be the way to make contact the easiest. They definitely do things differently In China than we do here in the US. Just clicking on items in Alibaba to see how much things “might” cost has generated orders that still are awaiting payment. I have been cautious. Some of these Solar Sellers have shoes and underwear for sale ON THE SAME PAGE. I’ve been so cautious, that I try to find out if these company representatives with “English names”, even exist, or are legit. I found one with the same name from BlueSun on LinkedIn so I reached out with an enquirery. Dorsey, from BlueSun is a terrific saleswomen like Amy. They sell everything you need for solar. She has been helpful in so many ways. She has recorded video of her working at her desk, talked to me, she speaks English quite well. She sends me links to pod casts of new products in development. She gets answers and spec changes from her Engineers and responds so very quickly. Her price on batteries was a little high for me, and they were gel, so I mentioned and sent her a pic of the LiFePo4’s we are discussing here and she reached out to Amy. She let me know that it was a great price and that I should buy from her if that was what I was looking for.

So fast forward, please follow this crazy timeline: Friday 3:30 am here, Amy’s been working all day, 4:30pm in China, my first contact with her. After talking with her and negotiating she sent me a proposal at 6:30pm, but for some reason the link wouldn’t work. She sent me a link in my email, that too didn’t work, she said maybe give it a little time so I went to bed because it was 5:30am here and I had been up all night. Woke up at 11am on Friday, still didn’t work, sent her a message that we would work it out on Monday, it was midnight in China, have a good weekend and that I was still looking for a BMS and a charger. She answered right away with the specs of her BMS and Charger!!! Sooo, sitting in my car at 7:30pm Friday, listening to the astros while my wife was finishing her workout, lol, I pick up my phone and tried that link again, some how got it to work by relogging in to alibaba. PAID with Amex, 8:30pm get a message from Amy that she received payment and they would ship on Monday, but nooo, this morning, Saturday at 6:30 am, I get an 8 minute video of Amy standing over 32 LiFePo4 batteries with my name on them, with a multimeter on EACH ONE, except 4, all were within .002. Then a picture of all of them with my full name on every BOX, taped and ready to ship, she said they HAVE shipped and when she gets the tracking number from logistics, she’ll send it to me. Ordered, Paid, Tested and shipped in 24Hrs basically Excellent customer service!!
 

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well, measuring cells to show the voltage means technically absolutely nothing.
even a defective cell can show 3.2V. The problem will come when you charge or discharge them.
So i am not sure this video has any value other than please you.
For sure Xuba makes a great job taking order, sending battery in a nice packaging at a fair price..
The product is nice, i mean you at least get what you paid for and it makes others
similar products expensive.
 
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The value is that they are actually working my order and shipping it. Yeah, they could bait and switch, but there is no evidence of that happening. As far a I’m concerned we’re still way over paying for these batteries.
 
" I’m concerned we’re still way over paying for these batteries. "
if you get any suggestion to get better price, we are listening.
 
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