February 7, 20242 yr Hi all. My system is a kodak VMIII 3.24 with 2 x Giter G2500-24 batteries and 4 550w solar panels So I had a 1 Giter battery running since May 2022 and wanted to get a second battery to increase capacity, unfortunately the batteries were removed from market and I was unable to. Fast forward to December 2023 and I was able to source a used battery. I connected it up and realized that my old batteries SOH (State of health) is alot worse that the newly sourced one. Reason being is I didn't realize my BMS was not set up correctly and invertedly I overcharged the cells. Here is a small table I made comparing the 2 batteries. The BMS is now functional so SOC comes from that info and kWh from a watt meter I have connected. Top battery is my old original, the bad one. Bottom battery is the newly sourced one. As you can see the performance difference is quite significant. I want to know if I can salvage this? Option 1: Setup the bank and run it like it is. Bottom battery (good battery) is new master and feeds with positive wire to inverter. Top battery (bad battery) is slave and feeds with negative wire to inverter. this does cause varying depletion as the SOC's in both batteries don't correspond when inverter is powered by battery only Option 2: Both positive and negative come from master and it works harder that the slave, hopefully this will balance it out more. I don't mind being limited on discharge current, I just need more capacity for the long loadshedding hours and the inevitable power outage through the night. Your inputs will be greatly appreciated. TIA
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