"They sell it as "protected from over charging", guess it's notWould you expect them to stand behind the BMS if you connected the battery directly to a 120vac socket?
"They sell it as "protected from over charging", guess it's not
One of the batteries worked, the other did not..Most LFP batteries are sold with this expectation. But virtually none of them would protect under this circumstance. I believe your expectations are unreasonable (plug the battery into a wall socket and it will protect itself). Agree to disagree - but this is not unique to SoK.
One of the batteries worked as it should have the other did not..
Agreed, this would be for my battery compartment in my 5th wheel. I think a fire under my bedrooms closet floor would be a high risk as well. These things are known to go up pretty quickly.Halon releases a deadly gas when discharged on a fire , would not be good if released in a living environment.
Because if the BMS failed, it should have stopped sending power to the cells, I don't understand why people are failing to grasp this concept:Would you expect them to stand behind the BMS if you connected the battery directly to a 120vac socket?
If you had a JBD BMS, it disables the battery when it detects over voltage, so no power can go to the cells. I think someone needs to be a voltage test on these SOK to see if it really has over voltage protection. 17 volts is not a lot, unless the OP is not telling the facts and the over voltage was way over like 30 volts or something.
If you had a JBD BMS, it disables the battery when it detects over voltage, so no power can go to the cells. I think someone needs to be a voltage test on these SOK to see if it really has over voltage protection. 17 volts is not a lot, unless the OP is not telling the facts and the over voltage was way over like 30 volts or something.
He said 17plus. Which depending on panels (if residential) could be on up over 100v, depending on how many and how they are configured. If the BMS failed, no idea how many volts they were subjected to- I highly suspect that since SOKs can be wired in series that it was much higher than 17v!If you had a JBD BMS, it disables the battery when it detects over voltage, so no power can go to the cells. I think someone needs to be a voltage test on these SOK to see if it really has over voltage protection. 17 volts is not a lot, unless the OP is not telling the facts and the over voltage was way over like 30 volts or something.
@Alkaline As has been explained, every component has a failure threshold above which you get a catastrophic and likely undefined failure. MOSFETs, as used in most low cost BMSs for many good reasons, tend to fail closed. I think at least one 48V BMS has been inspected by @upnorthandpersonal and found to contain 100V rated MOSFETs. That is a reasonable margin, and above that the costs go up substantially. That said, as this potential issue becomes known, I think we'll see more devices showing the maximum fault voltage before damage in their spec.
Nope it should burn up and no longer allow power to go in our out of the unit. But if burns up and allows power to flow in/out then its a badly designed unit.Does anyone know of a BMS that will reliably disconnect when plugged into a 120Vac socket?
Nope it should burn up and no longer allow power to go in our out of the unit. But if burns up and allows power to flow in/out then its a badly designed unit.