A gift horse... best method to match used LiFePo4 Calb 180ah cells?
Summary; I was gifted 46 Calb 180ah cells that came off a dock yacht; owner upgraded to entire Victron package. My vessel runs on 24v, so I set them up in 8s5p (using 40 cells) with each bank having its own Daly 200a BMS. They are charged by six 285w solar panels in 3s2p configuration, feeding a Growatt 3000w hybrid solar charger. The cells were given to me individually so I initially did a mid charge to 3.3v each and parallel connected all of them for two days to equalize them and then matched them up by internal resistance: I thought it was a good way to match them.
However, after a few days the voltage have strayed between cells by more than .2 volts.
So my questions are as follows:
1. What would be the best way/method/procedure to match up these cells in groups of 8? Top balancing, bottom balancing, capacity testing (thats gonna take a while), etc....
2. Upon doing so, how could I manage/maintain the voltage between battery banks, once matching of individual cells are done?
Any suggestions would greatly be appreciated.
Be well
Gil
Summary; I was gifted 46 Calb 180ah cells that came off a dock yacht; owner upgraded to entire Victron package. My vessel runs on 24v, so I set them up in 8s5p (using 40 cells) with each bank having its own Daly 200a BMS. They are charged by six 285w solar panels in 3s2p configuration, feeding a Growatt 3000w hybrid solar charger. The cells were given to me individually so I initially did a mid charge to 3.3v each and parallel connected all of them for two days to equalize them and then matched them up by internal resistance: I thought it was a good way to match them.
However, after a few days the voltage have strayed between cells by more than .2 volts.
So my questions are as follows:
1. What would be the best way/method/procedure to match up these cells in groups of 8? Top balancing, bottom balancing, capacity testing (thats gonna take a while), etc....
2. Upon doing so, how could I manage/maintain the voltage between battery banks, once matching of individual cells are done?
Any suggestions would greatly be appreciated.
Be well
Gil