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

[ghostwriter66]

Yes I actually talk to these guys often just to be clear though I am not dealing with xuba its another company who deals in EVE cells. They are very responsive though. I have never had any issues with my paypal debit card other than it has a $3000.00 day limit so often times we need to arrange for multiple payments. which works fine.

sorry .. i keep thinking its Xuba for some reason ...

 

[Craig]

sorry .. i keep thinking its Xuba for some reason ...

Honestly I think they are all just wholesalers of the same battery

 

[Electric Personality]

I did some searching and either I missed it or it wasn't mentioned yet. Those that have victron Battery Monitors, what are you using as your settings ?

I have :

Charged Voltage: 13.8
Discharge Floor 20%
Tail Current 4%
Charged Detection Time 3 minutes
Peukert 1.05
Charge Efficiency Factor 98%
Current Threshold 0.10a
Time to Go 3 minutes

Is it worthwhile to hook up a midpoint voltage on a 4 cell battery? Getting ready to install my 712.

 

[rbreding]

Is it worthwhile to hook up a midpoint voltage on a 4 cell battery? Getting ready to install my 712.

Nope. That is what the BMS is for. Use the port on the shunt for a temp monitor.

 

[Capt Bill]

Possible Xuba 280 Ah LiFePO4 Capacity Problem: Advise Welcome: I have my 8 3.2v * 280 Ah Cells I purchased in March, that I obtained two months later at my California USA home: ... I have 8 3.2v 280Ah LiFePO4s hooked up to two MPP LV2424 All In Ones, plus a V.4.0 Chargery BMS8T (battery and solar wall picture attached). I have now cycled the batteries about 6 or 7 times from very close to full, & then close to empty; ... recharging at 60 Amps or 120 Amps. I think the Info. via my BMS indicates I may have one problem cell with higher internal resistance, that I currently think is not producing the rated 280 Amp-Hours (on my cell # 8). I am wonder how this looks to more experienced LiFePO4 folks. This is my first time ever DIY LifePO4 build. I attached a couple of BMS screen pictures from my last draw down showing cell # 8 bottoming out early as compared to the other cells, while also showing more internal resistance via what the Chargery BMS shows me. (pictures attached).

I Note: The cell imbalance picture I got from my last draw down of battery bank IS With All the Chargery BMS8T's Balance Options Turned On (balancing during charge, discharge, and storage), while my cut-out voltage of my All In Ones units were set at 21.4 or 21.6 volts (on that last run). For my further diagnosis picture: ... I intend to finish wiring my Chargery's discharge side SSR to fully turn off my All In One Inverters at 2.5 v cell voltage (instead of trusting a slightly higher total voltage setting of my All In Ones. I want to next see what kind of BMS pictures I get from my next draw down of fully charged and balanced cells. I think I then might get further info. from doing the same after I placing the questionable cell #8, in a different battery bank position (like #2 or #3).

... I am open to feedback and advise on this curve ball.. I currently think I may have received on below par 280 Ah LiFePO4 cell from Xuba, and will have to see if or how they might help resolve my issue (unless I figure out this is from something else). Feedback and any ideas for better testing are Welcome ... are welcome. ... Bill

 

[Craig]

yes that IR looks high seems to me its a bad cell. testing it individually would be best. Seems like The IR of all of them is wider than I would expect.

 

[bdbugbee]

Possible Xuba 280 Ah LiFePO4 Capacity Problem: Advise Welcome: I have my 8 3.2v * 280 Ah Cells I purchased in March, that I obtained two months later at my California USA home: ... I have 8 3.2v 280Ah LiFePO4s hooked up to two MPP LV2424 All In Ones, plus a V.4.0 Chargery BMS8T (battery and solar wall picture attached). I have now cycled the batteries about 6 or 7 times from very close to full, & then close to empty; ... recharging at 60 Amps or 120 Amps. I think the Info. via my BMS indicates I may have one problem cell with higher internal resistance, that I currently think is not producing the rated 280 Amp-Hours (on my cell # 8). I am wonder how this looks to more experienced LiFePO4 folks. This is my first time ever DIY LifePO4 build. I attached a couple of BMS screen pictures from my last draw down showing cell # 8 bottoming out early as compared to the other cells, while also showing more internal resistance via what the Chargery BMS shows me. (pictures attached).

I Note: The cell imbalance picture I got from my last draw down of battery bank IS With All the Chargery BMS8T's Balance Options Turned On (balancing during charge, discharge, and storage), while my cut-out voltage of my All In Ones units were set at 21.4 or 21.6 volts (on that last run). For my further diagnosis picture: ... I intend to finish wiring my Chargery's discharge side SSR to fully turn off my All In One Inverters at 2.5 v cell voltage (instead of trusting a slightly higher total voltage setting of my All In Ones. I want to next see what kind of BMS pictures I get from my next draw down of fully charged and balanced cells. I think I then might get further info. from doing the same after I placing the questionable cell #8, in a different battery bank position (like #2 or #3).

... I am open to feedback and advise on this curve ball.. I currently think I may have received on below par 280 Ah LiFePO4 cell from Xuba, and will have to see if or how they might help resolve my issue (unless I figure out this is from something else). Feedback and any ideas for better testing are Welcome ...View attachment 16249 are welcome. ... Bill

Did you top balance the pack with all cells in parallel charged to 3.6v before setting up your working configuration? Also, how did you get to the internal R screen on the Chargery?

 

[bdbugbee]

Possible Xuba 280 Ah LiFePO4 Capacity Problem: Advise Welcome: I have my 8 3.2v * 280 Ah Cells I purchased in March, that I obtained two months later at my California USA home: ... I have 8 3.2v 280Ah LiFePO4s hooked up to two MPP LV2424 All In Ones, plus a V.4.0 Chargery BMS8T (battery and solar wall picture attached). I have now cycled the batteries about 6 or 7 times from very close to full, & then close to empty; ... recharging at 60 Amps or 120 Amps. I think the Info. via my BMS indicates I may have one problem cell with higher internal resistance, that I currently think is not producing the rated 280 Amp-Hours (on my cell # 8). I am wonder how this looks to more experienced LiFePO4 folks. This is my first time ever DIY LifePO4 build. I attached a couple of BMS screen pictures from my last draw down showing cell # 8 bottoming out early as compared to the other cells, while also showing more internal resistance via what the Chargery BMS shows me. (pictures attached).

I Note: The cell imbalance picture I got from my last draw down of battery bank IS With All the Chargery BMS8T's Balance Options Turned On (balancing during charge, discharge, and storage), while my cut-out voltage of my All In Ones units were set at 21.4 or 21.6 volts (on that last run). For my further diagnosis picture: ... I intend to finish wiring my Chargery's discharge side SSR to fully turn off my All In One Inverters at 2.5 v cell voltage (instead of trusting a slightly higher total voltage setting of my All In Ones. I want to next see what kind of BMS pictures I get from my next draw down of fully charged and balanced cells. I think I then might get further info. from doing the same after I placing the questionable cell #8, in a different battery bank position (like #2 or #3).

... I am open to feedback and advise on this curve ball.. I currently think I may have received on below par 280 Ah LiFePO4 cell from Xuba, and will have to see if or how they might help resolve my issue (unless I figure out this is from something else). Feedback and any ideas for better testing are Welcome ...View attachment 16249 are welcome. ... Bill

Did Amy send you a video of the cell voltage and IR test before they were shipped? If so, what was the range that she tested? On the video she did for me all of mine were 0.13-0.14 m ohms.

 

[Craig]

Did Amy send you a video of the cell voltage and IR test before they were shipped? If so, what was the range that she tested? On the video she did for me all of mine were 0.13-0.14 m ohms.

How did she test resistance?

 

[bdbugbee]

How did she test resistance?

She had a meter that displayed it with the voltage readings. I could make it out on the video she sent me. Actually she didn't send it to me. She posted it as a message on the Alibaba message board associated with my order. The meter she was using clearly showed the milliohms and voltage for each cell.

 

[Airtime]

I think the Info. via my BMS indicates I may have one problem cell with higher internal resistance, that I currently think is not producing the rated 280 Amp-Hours (on my cell # 8).

Just curious if you have checked on contact resistance for that cell? Check all connections are tight and try cleaning the contacts or even swapping busbars around just to isolate. I don't know how Chargery measures IR but any contact/busbar resistance would get lumped in with the cell IR. It's not hard to get a few tenths of a milliohm contact resistance.

 

[Electric Personality]

Pumped! Ordered 25 May, fedex went live, should be here 01 July!

 

[Capt Bill]

Just curious if you have checked on contact resistance for that cell? Check all connections are tight and try cleaning the contacts or even swapping busbars around just to isolate. I don't know how Chargery measures IR but any contact/busbar resistance would get lumped in with the cell IR. It's not hard to get a few tenths of a milliohm contact resistance.

I have my wiring between BMS and all cells down tight and solid. I use to own a mechanic shop (1980s) and have wiring down tight, but this LiFePO4 world is a new arena. I will see what ohms I can record from that 9 wire wiring harness from BMS to batteries terminals before I switch my #8 cell (which I think is below par) with cell #7; ... just to see how that difference shows up in my BMS records after a battery drain run. ... Thanks for another idea.

 

[Raj174]

@Capt Bill, It's very likely the only reason cell number 8 reaches the bottom first is that it has a bit lower capacity than the other cells in the group. The label "280 amp hour" is a nominal designation. No two cells are likely to have the same capacity. They are usually within 1 or 2 percent of nominal, however 4 to 5 percent is not unheard of. When top balanced, the lowest capacity cell will always reach the bottom first. The balancing BMS may help, but its not usually enough to sufficiently slow down the voltage drop on this cell as it approaches the bottom of the discharge curve. If testing cell capacity, I'd suggest using the 20 hour discharge rate, which for this cell is 14 amps. So, although the cell may be 275ah, (just a guess) I would think that Xuba will consider it within 280ah nominal. The only way to know is test it and call them.

 

[sremick]

Good news is Amy gave me a 500 buck discount for putting up with alibaba..

?

Makes me wish I had problems checking out!

 

[apctjb]

Pulled the trigger and ordered 32 cells from Amy. After reading about credit payment problems decided to use wire transfer option. Was super easy and payment when through and confirmed the same day.

Thanks to all posters!! Your insights and advice are invaluable....

 

[Ampster]

Was super easy and payment when through and confirmed the same day.

I assume you used their bank Swift code? I can do wire transfers online with Chase.

 

[redmessengerbag]

got my cells, 4 @ 3.32v, all match, what do you guys use as insulation between cells before taping them all together to leave a sliver of space.

Btw I found the thickness of a single layer cardboard (amazon box) works well with the size of the bus bars Xuba included, is it a bad idea or too ghetto to glue/tape on some cardboard strips as spacer between cells?

 

[bdbugbee]

got my cells, 4 @ 3.32v, all match, what do you guys use as insulation between cells before taping them all together to leave a sliver of space.

Btw I found the thickness of a single layer cardboard (amazon box) works well with the size of the bus bars Xuba included, is it a bad idea or too ghetto to glue/tape on some cardboard strips as spacer between cells?

I used doubled sided VHB tape at the four corners between cells. Double tape on the top corners, single on the bottom corners, since my cells have a very slight bulge on the lower half of the cell when they are fully charged. This kept my cells in good alignment when I used heat tape to bind the cells together and then when I compressed them together between 3/4" plywood end pieces. I only taped the cells in groups of 4 cells each so that if I ever need to take them apart in the future, I'm dealing with a 45 lb block of 4 cells and not a 90 lb pound block of eight cells.

 

[apctjb]

did you use western union or bank to bank?

Alibaba presented 3 payment options for my order with Xuba; credit card (~$100 fee), wire transfer or ACH (bank to bank , no fee), or Western Union. I selected wire transfer. Alibaba then provided detailed wire instructions specific for my order which I forwarded to my bank. Note for US orders Alibaba is using CitiBank NY, so the wire transfer is to a US bank and clears right away. I did a wire but you could also do ACH. I guess if I used my AMEX card I would have had an additional layer of fraud protection, but did not feel that was really necessary based on the reviews I read on this forum.

 

[apctjb]

Placed order on Friday and today (Sunday) I received message from Amy with video of testing of cell voltages (all 32 were 3.29xx) and that they will ship tomorrow. That was fast. Now the long sea voyage....

 

[Gazoo]

Alibaba presented 3 payment options for my order with Xuba; credit card (~$100 fee)

I didn't know they charge a fee for using a credit card? Anyways good to know they will be on the way soon.

 

[Freep]

got my cells, 4 @ 3.32v, all match, what do you guys use as insulation between cells before taping them all together to leave a sliver of space.

Btw I found the thickness of a single layer cardboard (amazon box) works well with the size of the bus bars Xuba included, is it a bad idea or too ghetto to glue/tape on some cardboard strips as spacer between cells?

I used a little velcro at the top and the bottom of each cell for spacing and to keep them from sliding. I found that even after using hose clamps the cells would shift a little putting strain on the buss bars and terminals. I also slipped a little styrofoam from the packing into the corners between each cell and trimmed the excess for a little more spacing.

 

[Capt Bill]

My Xuba 280 Ah LiFePO4 Capacity Problem:

I believe one of the eight 3.2v 280 Ah cells I purchased from Xuba is only getting about 170 Amp Hours. My current take: One below par (defective) cell Reduces my 24v 280 Ah battery bank Capacity to about 170 Amp Hour of useful Capacity.

********
Here is copy of my dialog with Xuba:

280 Ah LiFePO4 Capacity Problem:

I believe one of 3.2v * 280 Ah LiFePO4 cells I purchased form you is only 170 Amp Hour max. My Chargery BMS8T interface shows cell #6 empty @ 2.5v at about 170 Ah (about 109 Ah left on the 7 other cells) ; plus shows cell #6 with more internal resistance. Cell #6 reduces my whole 24v 280 Ah battery bank Capacity to about 170 Amp Hour of useful Capacity.

My Documentation: Please examine my pictures (attached) from full charge to one cell empty early. Pictures from my BMS8T include: Full charge with balanced cells. Then Cell # 6 empty early, with excessive internal resistance. Then cell # 6 shows even more internal resistance when I apply about 95 amp charge to full battery bank.

I believe I am looking at a defective cell problem. I am sharing this same documentation with the DIY Solar Forum, and asking for feedback. I request you Hellp: I want the 280 Ah of LiFePO4 Battery Capacity I purchased. Can you help me with this problem? Cordially, William Self in California USA.

*********
Additional Info. to this forum thread: I am documenting Full to Empty via Pictures of MY BMS8T. My below par cell was in position # 8 last week. My resistance check of my wire connections between BMS to each cell of the battery revealed all connections solid producing 0 ohms measurements. I swapped the problem cell from position #8 to position # 6, and the problem shown on BMS interface shifted to position #6.

I am open to question, or any suggestions. I hope Xuba can help me get the 280 Ah of LiFePO4 Battery Capacity I purchased. ... I will let you know how they treat me. Not a Happy Camper on this one, while also knowing this kind of mishap can happen to anyone. :+) Bill

 

[Ampster]

I will be curious to know what kind of documentation Amy requires. I thought you did a pretty thorough analysis short of capacity testing that cell. I suspect that would only confirm your hypothesis.