Steve_S
Offgrid Cabineer, N.E. Ontario, Canada
First things first. Likely you only damaged the one cell, which puffed up. More than likely it got too much charge or took too much for some reason, it could be internal failure (not that likely) or something else wrong like bad connections. Test each cell independently and write down teh voltages and resistance, mark that on a sticky note (or tape it to cell). A BMS should have disconnected though when one cell went out of spec, this is one of the key functions of the BMS to control each cell within a pack.
Terms:
Pack = a set of cells assembled to make a Battery Pack complete with it's own BMS.
Bank = a set of 2 or more Packs configured to collectively deliver more Amp Hours and Voltage depending on configuration.
You will need to split up the packs and set the cells up in Parallel. That means (+ to +) and (- to -) so they share out the voltage and balance themselves down. They will likely have to sit a couple of days till they all read the same voltage. It may be good to do that with the 16 cells in the good pack and the 15 cells in the pack that had the wonky cell. You will have to order another identical cell to replace the puffed up one of course.
‼ Forget the puffed up cell, consider it dead and dangerous, do not use it.
Once you have all the cells back to "normalised" voltages, then you'll have to do at least a Top Balance to ensure they are uniform.
BMS (Battery Management System)
A BMS is a key component that manages the cells and what happens to / with them. A basic BMS will protect from over/under charge and Over-temp conditions. Some more advanced BMS can do balancing between the cells and even more advanced ones can do more with interactivity. A BMS can cost anywhere from $75 (basic & simple) to thousands (insane gear for EV's + bigger stuff) but for < $200 USD you can get a wide variety of choices & options for BMS'.
You mention having a Victron Smartsolar 250/100 for 48v SCC (Great Stuff BTW) but not what Inverter/Charger you have. Victron is a Tier-1 product and they support LFP quite well. Their equipment can be made to interact with LFP battery packs so they can do their job most efficiently. IF you are in the "Victron Family" then I very highly recommend using two 16-S BMS' (one per pack) which can interact with Victron Systems so you can get the most from your investment. I cannot specify a particular BMS that will interact with Victron, there are several and there are threads in here discussing such in great detail. Even threads on using the Victron Software to manage it all nicely.
Once you know the status of all your cells, you will know which ones are toast, hopefully just the one which took the brunt, then you can order replacements as needed. I very highly doubt the vendor would take any responsibility, it's not their fault. If it is only one or two cells, count yourself very lucky indeed.
BTW: Personal Opinion: Some may say going without a BMS is OK... I say it's IDIOCY ! Yes you can live in a house with no fire / smoke detector or one with, which is safer @ 3am if the house catches fire ? We put thousands of dollars into battery systems and to not put failsafe protection on them is really dimwitted and risky. We install fuses & breakers for good reason and the BMS is the Last Stop should something go awry.
Terms:
Pack = a set of cells assembled to make a Battery Pack complete with it's own BMS.
Bank = a set of 2 or more Packs configured to collectively deliver more Amp Hours and Voltage depending on configuration.
You will need to split up the packs and set the cells up in Parallel. That means (+ to +) and (- to -) so they share out the voltage and balance themselves down. They will likely have to sit a couple of days till they all read the same voltage. It may be good to do that with the 16 cells in the good pack and the 15 cells in the pack that had the wonky cell. You will have to order another identical cell to replace the puffed up one of course.
‼ Forget the puffed up cell, consider it dead and dangerous, do not use it.
Once you have all the cells back to "normalised" voltages, then you'll have to do at least a Top Balance to ensure they are uniform.
BMS (Battery Management System)
A BMS is a key component that manages the cells and what happens to / with them. A basic BMS will protect from over/under charge and Over-temp conditions. Some more advanced BMS can do balancing between the cells and even more advanced ones can do more with interactivity. A BMS can cost anywhere from $75 (basic & simple) to thousands (insane gear for EV's + bigger stuff) but for < $200 USD you can get a wide variety of choices & options for BMS'.
You mention having a Victron Smartsolar 250/100 for 48v SCC (Great Stuff BTW) but not what Inverter/Charger you have. Victron is a Tier-1 product and they support LFP quite well. Their equipment can be made to interact with LFP battery packs so they can do their job most efficiently. IF you are in the "Victron Family" then I very highly recommend using two 16-S BMS' (one per pack) which can interact with Victron Systems so you can get the most from your investment. I cannot specify a particular BMS that will interact with Victron, there are several and there are threads in here discussing such in great detail. Even threads on using the Victron Software to manage it all nicely.
Once you know the status of all your cells, you will know which ones are toast, hopefully just the one which took the brunt, then you can order replacements as needed. I very highly doubt the vendor would take any responsibility, it's not their fault. If it is only one or two cells, count yourself very lucky indeed.
BTW: Personal Opinion: Some may say going without a BMS is OK... I say it's IDIOCY ! Yes you can live in a house with no fire / smoke detector or one with, which is safer @ 3am if the house catches fire ? We put thousands of dollars into battery systems and to not put failsafe protection on them is really dimwitted and risky. We install fuses & breakers for good reason and the BMS is the Last Stop should something go awry.
