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

Steve_S

Offgrid Cabineer, N.E. Ontario, Canada
Joined
Oct 29, 2019
Messages
7,694
Location
Rural NE Ontario Canada
Good Day Everyone.

Based on Another Ongoing Thread (link) I made the choice to pull the trigger on purchasing 16 pieces, 280AH LFP cells from Shenzhen Xuba Electronics via Alibaba.
Product Link. The order will be finalised on Monday Feb.03 due to new complications thanks to Murphy's Laws. So I am posting somewhat ahead.

After spending just over 2 hours in "chat" with their rep, I am quite reassured and like in the other thread, I was told that the cells would be tested & matched and a video provided as well. I also purchased the accompanying cell Bus Bars @ $0.80 each including the bolts. This is far cheaper & easier than making up my own from copper stock.

Product price (16 cells) = $1322.72 + Air-Freight $1093 + 22 bus bars $17.6 = Grand Total $2433.32 USD delivered to my door in Ontario Canada near Algonquin Park.
NOTE on S&H: The price that comes up automatically for the USA is a general base cost, specific destinations may vary. Pkg weight is 110 Kgs / 242 Lbs.

I will be taking these 16 Cells and building two 8S (24V/280AH) packs, each with a Chargery BMS8T-300 an using 2-200A relays in concert with each pack. This will provide me with 560AH plus the existing 375AH from the redone ShunBin Pack for a total of 935AH at 24volts which is a respectable battery bank for my use.

The configuration will be 3 LFP Packs, each with BMS & Relays will be connected to a common POS & NEG Bus Bars which in turn are connected to a Blue Sea 3-way switch. The 3-Way allows me to leave my 24V/856AH (428AH net useable) in place as a backup battery bank as the LFFP bank takes over main storage duty. As a result of having Mixed Chemistries, charging profiles become a bit of a pain, fortunately as the FLA Bank will be backup, I have an FLA Profile setup for my Samlex EVO-4024 Inverter/Charger for when I need to recharge the FLA bank through the inverter and another profile for LFP stored on the SDHCcard in the Samlex Remote Controller.

Components list of items not linked above.
The Text in Blue above are Links, just as they are in my signature for more info.
Blue Sea 9100e Switch: https://www.bluesea.com/products/9001e/e-Series_Selector_Battery_Switch
Blue Sea MRBF Terminal Fuse Blocks with 200A fuses: https://www.bluesea.com/products/5191/MRBF_Terminal_Fuse_Block_-_30_to_300A
- Each LFP pack gets a fuse.
2, 4 Stud (3/8) 250A Bus Bars with covers (one red, one black) https://baymarinesupply.com/busbars-4-stud-250a.html
1 Deltec 500A/50mv shunt for each LFP pack : https://www.amazon.com/AMMETER-SHUN...words=deltec+500A+shunt&qid=1580330079&sr=8-1 ** I prefer to use these as opposed to those supplied by Chargery.
 
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marker page for more configuration info oriented to "my build & spec"

Basic logical design for the "Bank" Assembly with 3 packs.
LFP-Parallel packs.jpg

Current configuration (logical diagram) showing only one LFP pack but enough to provide an idea of how it's going to be configured.
The Shunt Shown is a Deltec 500A/50mv unit (my preference) All Shunts will be behind the NEG busbar on the battery side.
Our Solar Diagram V3 (01-2020).jpg

Battery Layouts / Configurations possible:
24V-8S square pack.jpg
48V-16S square pack.jpg

series-pack-layout.JPG

The 24V/350AH Shunbin Pack layout. (16 cell long format using 175AH cells)
! NOT OPTIMAL ! only allows for an 8S BMS with paired cells.
LFP-Pack layout.jpg

multi-parallel-packs.jpg
 
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Thank you for this information, Steve.

I last chatted with Xuba on 20 Jan 2020. At that time the representative told me they are entering the Spring Festival Holiday until 5 Feb 2020, and asked if he could contact me then. Not sure why he said that given that you are apparently able to order now (or Monday).

I've been considering these for an 8S 24v mobile system @280AH @ USD 1,076.56 [SHIPPED] vs doing a 16 cell system in 2P8S using 150AH cells, for a 24V 300AH system @ USD 1,597.06 [SHIPPED] (BLS on AliExpress). The 150AH cells look to use larger bolts (280AH use M4) and may be more robust being smaller. But they are $520 more and shipping looks like it would be much slower (2 months). Will probably go with the 280AH.
 
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marker page for more configuration info oriented to "my build & spec"

Basic logical design for the "Bank" Assembly with 3 packs.
View attachment 6157

Current configuration (logical diagram) showing only one LFP pack but enough to provide an idea of how it's going to be configured.
The Shunt Shown is a Deltec 500A/50mv unit (my preference) All Shunts will be behind the NEG busbar on the battery side.
View attachment 6158
Sorry to hijack this thread but I keep looking at this Chargery diagram and cant figure out why we have 2 relays on same positive leg. If either one of these shuts down there is nothing going in or out of the battery.
 
Thank you for this information, Steve.

I last chatted with Xuba on 20 Jan 2020. At that time the representative told me they are entering the Spring Festival Holiday until 5 Feb 2020, and asked if he could contact me then. Not sure why he said that given that you are apparently able to order now (or Monday).

I've been considering these for an 8S 24v mobile system @280AH @ USD 1,076.56 vs doing a 16 cell system in 2P8S using 150AH cells, for a 24V 300AH system @ USD 1,597.06 (BLS on AliExpress). The 150AH cells look to use larger bolts (280AH use M4) and may be more robust being smaller. But they are $520 more and shipping looks like it would be much slower (2 months). Will probably go with the 280AH.
Yeah I never got a shipping quote. They told me on Jan 20 that their logistics company would not be open till Feb 5.
 
Yeah I never got a shipping quote. They told me on Jan 20 that their logistics company would not be open till Feb 5.

Thank you for the confirmation, Barold. Shipping is calculated when you go to the link Steve posted in his first paragraph. And it is included for both quotes I mentioned in my previous post (Xuba and BLS). I should edit to reflect that.
 
I will likely order around the same time at Steve, and would be happy to compare notes on shipping time (I'm in Western US), cell capacities, etc. I have no experience in counting coulombs, but will do my best.
 
Sorry to hijack this thread but I keep looking at this Chargery diagram and cant figure out why we have 2 relays on same positive leg. If either one of these shuts down there is nothing going in or out of the battery.
I'm using the installation method as described on Page 20 of the BMS8T docs. As I charge batteries via the SCC & Inverter, there is no separate circuit for charging. If I had a third external charge source for the LFP then that would be directed to that circuit. They are flexible in how you install per your needs & requirements and not knowing what the future will present and change potential, I prefer more flexibility / options to change my configurations without having to replace things like a BMS.

The "Shipping Charges" which you see on the website are "generic" and specific charges are calculated when you start to place the order as that has to be calculated to the door. I only got better rate calculation because the rep was cross verifying it as we were chatting via the Alibaba tool, in fact the rep was using a smartphone to do business while visiting family for the holidays.

@Carly I have an existing 8S2P pack (the ShunBin thing) and to be honest, it's a pain to furtle with at 70kgs / 150lbs and being in that config it uses an 8S BMS because the cells are paired, which IMO is not optimal. This is the reason I chose to apply KISS and build two "clean" 8S packs, yes it's an extra BMS but I prefer to manage / monitor each cell. I was told it would take 10 days air freight once the courier had the order in their hands, to get it to me. So take the lead time for them to pick, test & match and to get the package to the courier, tack that on and so it becomes something like 1 month for receipt I guess. Guess I'll know by the end of February lol.
 
Are you satisfied with the buss bars? It looks like the contact patch is very small.
 
busbar rule says you need 1 square milimeter per amp (for copper) , so a bar that is 25 x 2 is 50A
since on battery busbar is usually very short, you can accept up to half.
so 25x2 mm bar should be ok for 100A
ideally no busbar should be thinner than 3mm, best 4mm
 
Correct notation is : xPxS . Therefore 1P4S denotes 4 x cells in series only. 2P4S denotes 2 banks of (4 x cells in series) connected in parallel or do
I have it wrong ?
 
Correct notation is : xPxS . Therefore 1P4S denotes 4 x cells in series only. 2P4S denotes 2 banks of (4 x cells in series) connected in parallel or do
I have it wrong ?

I interpret 2p4s as "parallel two cells, then put four of those in series." As in, read it and do things from left to right.

Since the nomenclature is easily misinterpreted, sometime I just write {2p, then 4s} to make things clearer.
 
notation is clear, 2P4S is not 4S2P
you always take a "cell" (even if it is several cell in parallel or serie, then you take the "group of cell". from the smallest element to the biggest.
so if you want 200A with 2x 100A in parallel you will put them first 2P, then if you put 4 like this in serie, it become 2P4S.
but you can also make 2 string of 4 cells (4S) and put 2 strings in parallel, so 4S2P.
you would end up with the same battery 200A 12V, but different geometry.
think at the way you would assemble the battery.
if by any chance you would expand this configuration by adding a second one in serie, it woudle be 4S2P2S
 
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I'm using the installation method as described on Page 20 of the BMS8T docs. As I charge batteries via the SCC & Inverter, there is no separate circuit for charging. If I had a third external charge source for the LFP then that would be directed to that circuit. They are flexible in how you install per your needs & requirements and not knowing what the future will present and change potential, I prefer more flexibility / options to change my configurations without having to replace things like a BMS.

The "Shipping Charges" which you see on the website are "generic" and specific charges are calculated when you start to place the order as that has to be calculated to the door. I only got better rate calculation because the rep was cross verifying it as we were chatting via the Alibaba tool, in fact the rep was using a smartphone to do business while visiting family for the holidays.

@Carly I have an existing 8S2P pack (the ShunBin thing) and to be honest, it's a pain to furtle with at 70kgs / 150lbs and being in that config it uses an 8S BMS because the cells are paired, which IMO is not optimal. This is the reason I chose to apply KISS and build two "clean" 8S packs, yes it's an extra BMS but I prefer to manage / monitor each cell. I was told it would take 10 days air freight once the courier had the order in their hands, to get it to me. So take the lead time for them to pick, test & match and to get the package to the courier, tack that on and so it becomes something like 1 month for receipt I guess. Guess I'll know by the end of February lol.
Yes I see their instructions say that. But my question is if the battery gets disconnected through the relay for undervoltage how is it going to charge if its disconnected by relay. And the converse if its disconnected through overvoltage how would it drain? Sorry that I may be coming off as dense
 
Yes I see their instructions say that. But my question is if the battery gets disconnected through the relay for undervoltage how is it going to charge if its disconnected by relay. And the converse if its disconnected through overvoltage how would it drain? Sorry that I may be coming off as dense
Ohh Noo makes perfect sense & good question !
The doc's make no mention of the recovery process which I think this qualifies as that. I believe how it works is the Relay's get pulsed and stay active relative to what the reading is from the shunt, now if the battery itself is powering the BMS and if it is dead, you have a problem but the BMS doesn't take much at all, so I think it would be ok. I can't be 100% certain on this though, it's extrapolation from their "English" docs. The way I have it setup is like a common port BMS more or less. I'm also here 24/7 so if it doesn't work out I can furtle with it. Now, when I build the next two, using these 280AH cells and put them into place, I may have to use the delay boards for the BMS' as well, I don't know yet.

If I was only using a SCC & regular Charger on one side and an Inverter for AC output on the other, then the whole issue would be much simpler, which is more like how an EV is setup (well minus the SCC). As I am using an Inverter/Charger + SCC on a common bus topology, it is the way it is.
 
@Carly I have an existing 8S2P pack (the ShunBin thing) and to be honest, it's a pain to furtle with at 70kgs / 150lbs and being in that config it uses an 8S BMS because the cells are paired, which IMO is not optimal. This is the reason I chose to apply KISS and build two "clean" 8S packs, yes it's an extra BMS but I prefer to manage / monitor each cell. I was told it would take 10 days air freight once the courier had the order in their hands, to get it to me. So take the lead time for them to pick, test & match and to get the package to the courier, tack that on and so it becomes something like 1 month for receipt I guess. Guess I'll know by the end of February lol.
Thanks so much for the info. They told me the logistics company doesn't resume work until Feb 9, and asked if that was acceptable to me (it was). I was quoted USD 1050 and change for 8 280AH cells, 10 bus bars (at 80 cents/each), and shipping. Unfortunately, I keep getting an error when trying to pay via credit card. My credit card company says there is no problem, so I am still trouble shooting.
 

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