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.
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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.
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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
Heads Up: I got a 2nd Bad Roll of Dice on my Replacement Battery from Xuba: It took a couple of months via sea freight, & then Fedex to my California door. I have been busy on other projects (installed a couple of Pioneer brand 12000 BTU Mini Split heat pumps), and slowed down by cycles of smoke from nearby forest fires, and hot weather on top of my age in Northern California. Re my earlier 8 x 280 Ah LiFePO$ Battery purchase from Xuba via Amy; ... I just integrated the new replacement battery I got from Xuba to my 24v 280 Ah battery Bank. Xuba was kind enough to send me a replacement after I documented how one of my 8 batteries purchase from them got down to 2.5 volts early (at about 170 AH). WOW,
The Replacement Battery is worse than my only 170 Ah out of a 280 Ah rated original battery problem. That original problem in effect limited my whole 280 Ah battery bank to only 170 Ah when I purchased for 280 Ahs !
I will put my story together with pictures from my Chargery BMS8T Display (again) to document how this 280 Ah replacement battery from Xuba that I just put on line is worse than my original one 3.2v cell short in Ahs ... Battery Problem. My Current Thoughts: I think one or twice can be a mistake, but three times or more is a pattern. and Wow, ... Why Me?
Additional brief; before I document w pictures: I first tested my one 3.2 volt 280 Amp/Hr free of charge "Replacement Battery" on that fan unit that only draws 180 watts at about 20 amps (on one 3.2v cell). I only got 262 Ah going from full charge to 2.5 volt cut off. It had originally cut off at even less Ah (like 240 Ah, but I got a few more Amp Hours by dialing the Amp draw from 20 A to 10 A or less. The Bigger Test ( that I suggest considering with something like the Chargery BMS display details) was getting my new replacement battery integrated to my 24v Battery Bank, balanced in voltage with the other 7 cells, plus all fully charged. I then powered the sub panel of my house through my three LV2424 All In Ones (with no solar input, only battery draw), drawing various amounts of battery amps for may 10 to 100 or 120 amps; that included a 22 amp draw when running my evaporator cooler; a 43 amp draw when running one mini split heat pump in AC mode; and a 90 amp draw cycle when running two 12000 BTU mini split heat pumps in AC mode. My Chargery BMS8T cut out
my 24v LiFePO4 battery bank Early via my relays / when this new replacement battery drained fast at it's low end to 2.5 volts; while the other good batteries cells were still showing about 3.25 v with plenty of Ah left in em. I was charging at 120 amps, well with the capabilities of these LiFePO4 batteries, but Also noticed from my Chargery Display Info. (I LIKE how I can cycle through several pages of detailed info.) that my 8 LiFePO4s batteries can also get out of balance at the upper end of my higher Amp Battery Charge Cycles / like when charging at 120 + amps. I thus reset my charge rate to about 60 amps or less, to get fully charged batteries all in balance before cycling another load test. I had hoped a second full charge and amp drain cycle might show different picture. Instead I have two battery bank drain cycles confirming to me I have a worse problem with this new replacement battery as compare to the orginal 280 Ah rated LiFePO4 that has only 170Ah ability. ... I hope more people are checking their Ah and comparing notes in this forum. Checking Amp/Hrs against rating ... sooner than later, ... might be a good idea. I will put in my picture documentation in awhile, as I will be assembling that for Xuba too. I wonder how Xuba might be responding to me on this one. I am not a happy camper about this roll of dice. Rolling with it while valuing this forum. ... Bill