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

Just scanning last few pages of thread got me writing. I purchase my 1st set of 8 x 280 Ah LifePO4 from Xuba via Amy 4-2020, and a 2nd set from Amy's new company (I think a with her husband effort)... about a year plus later. Had one bad cell on first order that I documented on this forum, and got free Xuba replacement (took sea freight time); and I left second set from Amy newer company stored top balance connected (month plus, maybe too long?) The Ah check on second set seemed a bit low. I recently rotated newer set with older previous 8 cell battery bank, and I think one cell drains early, on not so recent order (would have been smarter to put online earlier to realy test em out under fuller load and charge cycle conditions). ... Non of my two purchases have resulted in straight sided cells. In my previous question cycles, some slight bulging at battery side cases seem to be the norm, but I am not sure. In exploring recommendations for compressing cells for longevity sake, I wonder what stress that puts on battery terminal with the solid bus bars on batteries with slight bulging on side planes; thinking full battery bank dimensions woud likely change slightly with charge and discharge heat n cool cycles. ... . Does anyone think about disconnecting their BMS, and then loosening (before re-tightening) the bus bar connects to let battery get a new set once in awhile; for possibly de-stressing battery terminals (or tested for if there is terminal stress over time)? ... While I DO LIKE how much better these 280Ah EVE batteries are over any Lead Acid version; My Biggest Question: Does anyone have a source A-Grade 280 Ah LiFePO4s with straight sides? IF so, who is selling those? I personally think the cells I have are B-Grade cells, while pretty sure I was told when purchasing from XUBA they were A grade, and then on 2nd set, when I asked if these were A Grade; the reply I remember was something like ..."Don't worry ..." ... For me, I consider my experience with LiFePO4s as mostly good with some learning curves. I would like to know if straight sided 280Ah LiFePO4 cells are available at some kind reasonable price. I would take straight side planes on the the battery cell as symbol of them being A-Grade ... :+)
 
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Cells will expand and contract with charging and discharging. IMO the only way to completely relieve stress on the cell terminals is to use braided busbars or cables for the cells interconnects. I do get your point concerning straight sided cells. I have often wondered if the manufacturers testing causes the cell to expand and maybe that could be a reason why the cells are rejected. Some suppliers also test cells which might contribute to the expansion. I wonder if the new Grade A tested and matched cells Amy is selling have any expansion when received by the customer? Lots of mysteries. On the other hand if one receives expanded cells and they perform well I don't think there is anything to worry about provided the cells are mounted in some type of compression fixture.
 
FYI, XUBA has changed since this thread was started. I cannot & will not suggest them as a Vendor but it is Your Dice Roll to take.
Be advised and aware of it. There are Known Good Reliable vendors to choose from.
 
Just scanning last few pages of thread got me writing. I purchase my 1st set of 8 x 280 Ah LifePO4 from Xuba via Amy 4-2020, and a 2nd set from Amy's new company (I think a with her husband effort)... about a year plus later. Had one bad cell on first order that I documented on this forum, and got free Xuba replacement (took sea freight time); and I left second set from Amy newer company stored top balance connected (month plus, maybe too long?) The Ah check on second set seemed a bit low. I recently rotated newer set with older previous 8 cell battery bank, and I think one cell drains early, on not so recent order (would have been smarter to put online earlier to realy test em out under fuller load and charge cycle conditions). ... Non of my two purchases have resulted in straight sided cells. In my previous question cycles, some slight bulging at battery side cases seem to be the norm, but I am not sure. In exploring recommendations for compressing cells for longevity sake, I wonder what stress that puts on battery terminal with the solid bus bars on batteries with slight bulging on side planes; thinking full battery bank dimensions woud likely change slightly with charge and discharge heat n cool cycles. ... . Does anyone think about disconnecting their BMS, and then loosening (before re-tightening) the bus bar connects to let battery get a new set once in awhile; for possibly de-stressing battery terminals (or tested for if there is terminal stress over time)? ... While I DO LIKE how much better these 280Ah EVE batteries are over any Lead Acid version; My Biggest Question: Does anyone have a source A-Grade 280 Ah LiFePO4s with straight sides? IF so, who is selling those? I personally think the cells I have are B-Grade cells, while pretty sure I was told when purchasing from XUBA they were A grade, and then on 2nd set, when I asked if these were A Grade; the reply I remember was something like ..."Don't worry ..." ... For me, I consider my experience with LiFePO4s as mostly good with some learning curves. I would like to know if straight sided 280Ah LiFePO4 cells are available at some kind reasonable price. I would take straight side planes on the the battery cell as symbol of them being A-Grade ... :+)
I think due to the thinness of the aluminum, and the weight of what is inside them, most large cells will be hard to get absolutely flat sides. Compression will help a lot on the big cells. Stepping down a notch in size, the true grade A cells (105AH) I purchased from Amy at Shenzhen Luyuan, and they are indeed flat as a board, and met every aspect of the test reports I was sent (from Eve).

Yes, real grade A cells are available, but you do pay extra. Even then, I think the largest versions will not be 100% straight, although I'm sure they are less bulged than many people are receiving (obviously used and abused cells from the pictures).


My source for true grade A cells. This is the Amy that used to work at Xuba, just FYI.
 
I am the OP who started this Thread. XUBA Changed seriously since this thread started, I no longer suggest this company. Luyuan is certainly a GOTO Known Good Reliable Vendor / Supplier.
 
SOP for buying from the interweb:
1. Buy with a major CC
2. Inspect items promptly, make videos of opening items if possible
3. If Items are not as advertised, send written request for remedy to seller promptly
4. Seller will either make you whole or fluke you.
5. If you are fluked - send one more request to seller for remedy and spell out remedy (like refund of apportioned amount if partial order is not usable)
6. Call CC and dispute charge and send in proof.
 
我是发起这个帖子的OP。XUBA 自从这个帖子开始以来发生了严重的变化,我不再推荐这家公司。绿源无疑是 GOTO 知名可靠供应商/供应商。
你好,
你知道在我们XUBA之前公司发生了什么变化吗?
我可以告诉你XUBA公司开业以来发生的所有事情以及一些人所做的坏事。
我读了很多关于 XUBA 给你们带来的问题的文章,我真的很生气。
因为这不是现任公司人员造成的。
如果你想听的话,我可以告诉你从XUBA以来发生的所有事情。
 
XUBA Changed

Umm no.. they didn't' they were always the same, sold grade B just like literally every Alibaba seller and lied about it, including Amy (even though I don't think she knew what she was selling) when she worked for them. Luyuan is the only Legit Alibaba seller, but fact is a good bit of her sales are now grade B cells which are overpriced grade B vs the rest. In the US you have 3 grade A alternatives: sfk, ezeal, 18650 are priced very close to luyuan actually can be cheaper with less wait. For grade B you have docan & eel. Not much left for Luyuan in the US/North America at this point tbh.

Solution: Luyuan needs to open a US warehouse.
 
If what I got from Xuba when Amy was there are grade B, then I'll be buying grade B again. My cells are three years old now and they are well balanced no matter if I'm at 40% state of charge or 100% state of charge.
 
Yeah, IMNHO, Amy is the best hands down. Not always the cheapest, or the fastest, but always the best. I won't even think of buying cells from anyone else.
 
I have no doubt that I received Grade B from Amy and others three years ago, but they are working well for me. The price averaged $116 per kWh delivered.
 
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