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So where is the best place (via USA) to order Grade A 320/302/280ah EVE/CATL batteries from?

You'll have to replace the BMS each time you step up the voltage and cell count, but if you top-balance everything each time you reassemble the new pack you should be fine.
 
Increasing battery pack capacity later is best avoided if possible. For maximum performance and compatibility, it is best to build the pack from cells that each have individually tested and fully matched. Yes, this is a big task and many pass this over but it is way to build the very best packed for matched cells. Even cells from the same batch can vary slightly and cells from different batches can vary more. Not saying it happens often, just that cell variance does occur and more often with lesser-quality cells.

Grade B cells from typical vendors should be always be tested and get cells that are out from the others exchanged stratightway.
 
Alkaline said:
Long story, but if you want to search you'll find the 280K pulls marginal AH capacity. E.G. generally in the upper 270 like 276-278. These are for grade A cells with test reports that usually state capacity test in the 290 range. Grade B 280K were in the mid to low 260...

Its a clear contrast to the old 280N which easily tested in mid 290s all day long (the ones with test reports). The old 280N even grade B generally tested in the 278ish range. So many people view the 280K as actually a 270K.

304 is also good, usually testing in the mid 310 like 314.

EVE is supposed to come out with a version 3 of this cell to address these problems, word on the street is they test like the original 280N did, mid 290s.

One thing to remember is that the 280K has double the usage life of 6000 cycles vs the 3000 of the 304 or the original 280N. Currently Most US vendors have V1 or V2 of this cell.
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Well they have a new 280K that is supposed to be better / fix the 280K capacity problems, I caught a glimpse of it in the sfk video, it said 313 AH?
go to around 3:30 mark.
 
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houseofancients said:
Would make sure you add the closed capacity as you can , so eve 304 would be best..
Otherwise your 302 will take most pressure on charge and decharge
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Have not found that to be the case in my experience. I have a mix in the bank, EVE 280N's, EVE 280K's and EVE LF304's. All in parallel with large copper busbars running down each side of the cabinet.

Bank voltage is the same across the entire bank, monitored using Batrium CORE with K9's. Each battery remains at the same voltage during charge and discharge. I do have some 280K cells that don't hold balance as well as the rest of the bank (4 in total, delta is less than 30mv before balancing) but those were some unmatched cells I did get a deal on. The rest of those cells in that battery hold good balance. All were top balanced in parallel and tested before install.
 
Some updates for the cheapest prices from vendors with confirmed test reports (sorry I'm not putting Docan or EEL (only sells grade B) on this list, besides ezeal is Docan anyway...):

EVE 280K V2: https://ezealco.com/product/eve-280ah/
EVE 280K V3: https://www.sunfunkits.com/product/...f280k-version-3-280ah-certified-ess-32v-cells
EVE 105: https://ezealco.com/product-category/prismatic-cell/
EVE 230: https://ezealco.com/product/lifepo4-prismatic-battery-cells/
EVE 304: https://www.18650batterystore.com/products/eve-lf304-grade-a-cells-3-2v-lifepo4-304ah-battery
REPT 280: https://www.sunfunkits.com/product/58/4-pack-ruipi-rept-280-certified-ev-ess-grade-280-ah


With ezeal you can get a $20.00 coupon by there newsletter but can only be used once/account
with sfk you can get 5-8% off with there coupons listed depending on how you pay.


Finally if you are looking to buy a lot of cells, SFK has a pallet deal which comes out to about $143.50/cell delivered for the 280K V3 cells and they will ship to you from China, or you can pick them up from there warehouse, but if you need it shipped it from the USA it will cost you freight.

18650batterystore can be as low as $130.00/cell for the LF280K V2 if you buy over 100 cells, however, ezeal is still cheaper and doesn't require a minimum.


Overall I would say, Not too shabby and we have nice alternatives to Alibaba all 3 with phone numbers and real people who will respond.
 
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Best of luck to Luyuan, back when 18650 came to the scene I was man this is going to clobber Luyuan in the US... But now with ezeal and 18650 combined it's really going to be tuff for them. They maybe supplying sfk though due to similarities in packing, however, even with this I think they will be a boutique supplier at best. I hope they have better success in other parts of the world. Luyuan was the very first company to offer real genuine cells from China when grade B fraud was rampant.
 
Solar Guppy said:
As a friendly reminder to all, by the end of this year, 40 states in the USA will have adopted NEC2020 which includes UL9540 requirements for energy storage systems. This means in many location, the entire DYI of batteries would no longer be an acceptable ( allowed ) option.

Just keep in mind posts like talking about 10+ year expectations for payback maybe a mute point and that for many reasons those batteries would be "retired" long before there useful life would make that necessary.

Stay informed and always verify claims on what can actually be done and remain code compliant before one purchases any components for an energy storage system, the sellers of today have only one goal, to sell parts, not inform purchasers of what can be done with them.
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My state adopted it but it doesn’t matter because I live in the middle of nowhere with no code enforcement. Half the properties out here have outhouses or dump raw sewage into a pit.
 
luminaire801 said:
Hi guys, what do you think of Calb 280Ah cells?
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I bought a sample batch of CALB 280; the problem is that they are ONLY available in laser-weld terminals, not the beautiful bolt terminals that are available in the 230ah's. My solution was to send them over to a factory that does laser welding, however, they melted the black plastic of my cells and they looked like crap...certainly not something that someone would pay tip top dollar for (which brings me to my next point).

The real-deal brand new "grade A++" CALBs are ridiculously expensive. We're talking about $300/cell factory price before shipping. If after shipping we are talking over $330/cell, by the time you add a slim margin to get a retail price, then I think anyone in their right mind will go a different route. Even if they are 10% better, I doubt they are worth paying double for...especially for what we are using them for.

Sure, if I was building a performance EV, they would be my first choice...but for solar c/5 rates, just not worth it.
 
Industry Factory prices of LFP are around $91.00/KW as of June 2023 for un-assembled raw cells with passing test reports. Factoring warehouse/logistics cost I'd recon each of these cells cost resellers around $95.00 - $100.00 depending on how they pack/store them. So you see a selling price of around $120.00 in China as the typical company is making about $20.00/cell, hence a $125 selling price + shipping / transactional fees to buyers. So 1KW = $150-160 is what is direct from china or $150 + $15/$20 shipping from with in the US and that is exactly the range that these are selling for in the US.
 
Alkaline said:
Some updates for the cheapest prices from vendors with confirmed test reports (sorry I'm not putting Docan or EEL (only sells grade B) on this list, besides ezeal is Docan anyway...):

EVE 280K V2: https://ezealco.com/product/eve-280ah/
EVE 280K V3: https://www.sunfunkits.com/product/...f280k-version-3-280ah-certified-ess-32v-cells
EVE 105: https://ezealco.com/product-category/prismatic-cell/
EVE 230: https://ezealco.com/product/lifepo4-prismatic-battery-cells/
EVE 304: https://www.18650batterystore.com/products/eve-lf304-grade-a-cells-3-2v-lifepo4-304ah-battery
REPT 280: https://www.sunfunkits.com/product/58/4-pack-ruipi-rept-280-certified-ev-ess-grade-280-ah


With ezeal you can get a $20.00 coupon by there newsletter but can only be used once/account
with sfk you can get 5-8% off with there coupons listed depending on how you pay.


Finally if you are looking to buy a lot of cells, SFK has a pallet deal which comes out to about $143.50/cell delivered for the 280K V3 cells and they will ship to you from China, or you can pick them up from there warehouse, but if you need it shipped it from the USA it will cost you freight.

18650batterystore can be as low as $130.00/cell for the LF280K V2 if you buy over 100 cells, however, ezeal is still cheaper and doesn't require a minimum.


Overall I would say, Not too shabby and we have nice alternatives to Alibaba all 3 with phone numbers and real people who will respond.
Click to expand...
Where do you get the battery boxes for 100/200/300 ah in the US or do you just put them on a rack?
 
For a big 16 cell you can get from aliexpress: https://www.aliexpress.us/item/3256804748208695.html

4 cell: https://www.aliexpress.us/item/3256803318042354.html The shipping is higher than the case...

18650batterystore had the same thing but it has been out of stock for months I don't think its coming back.

www.18650batterystore.com

12V 280Ah Plastic Storage Case

345*190*245mm，with screws
www.18650batterystore.com www.18650batterystore.com

then there is the sfk kit: https://www.sunfunkits.com/product/72/sfk-v4-12v-basic-diy-kit expensive but also the most complete and well thought. I have the v4 kit wit heating with 280K cells from 18650batterystore.
 
EastFalcon said:
For a big 16 cell you can get from aliexpress: https://www.aliexpress.us/item/3256804748208695.html

4 cell: https://www.aliexpress.us/item/3256803318042354.html The shipping is higher than the case...

18650batterystore had the same thing but it has been out of stock for months I don't think its coming back.

www.18650batterystore.com

12V 280Ah Plastic Storage Case

345*190*245mm，with screws
www.18650batterystore.com www.18650batterystore.com

then there is the sfk kit: https://www.sunfunkits.com/product/72/sfk-v4-12v-basic-diy-kit expensive but also the most complete and well thought. I have the v4 kit wit heating with 280K cells from 18650batterystore.
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AliExpress really ?
Why can't people learn....?
 
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