Good day All, I'm having an issue, which from other forums I've read, appears to be a bad cell 
. I purchased 2 Rebel 12V 100AH LiFePO4 Battery from Rebel Battery on Ebay, which came in with a 20 cell(4-groups of 5) configuration from a new supplier, and is not what Rebel battery was looking for in their design, so these battery's were purchased at a discount. Battery's came shipped at around 3.30v, and are wired in series for my 24v system. I first discharged the batteries with a low 100-300watt pull from air purifier and fan, at which time I noticed one battery, cell 4, dropping very quickly and lower than the other 3 cells. Cell 4 showed around 2.9v, cells 1-3 showed 3.18v. I stopped the discharge and reached out to Aric, who advised: this is sometimes normal on the first discharge and to charge/discharge the battery's a few times. The second battery is perfect, 3.18v across all 4 cells. I started charging the battery's, 10-12amps, and noticed when cell 4, the cell which was showing low voltage on discharge, reached just over 3.4v, started to increase voltage at a very fast pace, and not staying balanced with cells 1-3, which were still showing 3.9v. Screen shots show cell 4 increasing from 3.5v to 3.53v in 15seconds, and then hitting the 3.65v BMS high voltage cutoff a few moments later, which shut down the charging to both battery's. I've discharged and charged, with the same results a few times, and feel there is a bad cell/s in one of the groups of 5. I emailed back Aric at Rebel battery's on 12/22, to see if he had any advice on what to try, but have not heard back yet, and figured it could be due to the holiday. If anyone has any advise on trying to resolve this issue without cutting open the battery and replace a bad cell, please let me know. Thank you, DW.
. I purchased 2 Rebel 12V 100AH LiFePO4 Battery from Rebel Battery on Ebay, which came in with a 20 cell(4-groups of 5) configuration from a new supplier, and is not what Rebel battery was looking for in their design, so these battery's were purchased at a discount. Battery's came shipped at around 3.30v, and are wired in series for my 24v system. I first discharged the batteries with a low 100-300watt pull from air purifier and fan, at which time I noticed one battery, cell 4, dropping very quickly and lower than the other 3 cells. Cell 4 showed around 2.9v, cells 1-3 showed 3.18v. I stopped the discharge and reached out to Aric, who advised: this is sometimes normal on the first discharge and to charge/discharge the battery's a few times. The second battery is perfect, 3.18v across all 4 cells. I started charging the battery's, 10-12amps, and noticed when cell 4, the cell which was showing low voltage on discharge, reached just over 3.4v, started to increase voltage at a very fast pace, and not staying balanced with cells 1-3, which were still showing 3.9v. Screen shots show cell 4 increasing from 3.5v to 3.53v in 15seconds, and then hitting the 3.65v BMS high voltage cutoff a few moments later, which shut down the charging to both battery's. I've discharged and charged, with the same results a few times, and feel there is a bad cell/s in one of the groups of 5. I emailed back Aric at Rebel battery's on 12/22, to see if he had any advice on what to try, but have not heard back yet, and figured it could be due to the holiday. If anyone has any advise on trying to resolve this issue without cutting open the battery and replace a bad cell, please let me know. Thank you, DW.
