Does taking a battery down to test the low voltage cut off damage the battery.

[kytoon]

Purchased a 100ah battery. Charged it up. Ran inverter and electric heater and took it down about 65 amp hours (per victron bluesmart charger). Brought back to full charge and now I've drawn down again. This time it's down to about 11.26 volts with load. So I'm in the last bit of remaining charge. Low voltage cut off is 10.8. It's getting tough with inverter and fan trying to get it down to test the low voltage cut off as the inverter doesn't want to work this low.

My questions are:
Would I potentially damage the battery trying to trip the low voltage cut off?
Is it wise to test this safety feature while it's still in the new phase?

Thanks for thoughts!

 

[BentleyJ]

When you say the cut-off is10.8V that corresponds to 2.7V per cell which is fine as long as the BMS does in fact work based on individual cell voltages and is not using the actual bulk voltage of 10.8 as the trigger. If you are going to perform the test, it would be a good idea to observe individual cell voltages if there is a way to communicate with and display BMS data.
Reason being, what if the test fails and the BMS doesn't kick off? You can stop the test otherwise you will never know if one of the cells went below the critical level of about 2.5V.

 

[kytoon]

This is cheapo sealed lifpo4. No way to test individual cells and does not have bluetooth to communicate each cell voltage. All of which is why I'm trying to put it through a couple paces on the front end. I've been tending it and checking voltage constantly in case low voltage cut off doesn't work. And yet if it's going to break I'd rather it do it now instead of 4 months from now when I'm using it regularly.

 

[MurphyGuy]

Purchased a 100ah battery. Charged it up. Ran inverter and electric heater and took it down about 65 amp hours (per victron bluesmart charger). Brought back to full charge and now I've drawn down again. This time it's down to about 11.26 volts with load. So I'm in the last bit of remaining charge. Low voltage cut off is 10.8. It's getting tough with inverter and fan trying to get it down to test the low voltage cut off as the inverter doesn't want to work this low.

My questions are:
Would I potentially damage the battery trying to trip the low voltage cut off?

NO, that's what the low voltage cut off is for.

Is it wise to test this safety feature while it's still in the new phase?

Yes, make sure it works, especially if its made in China.

Thanks for thoughts!

 

[MisterSandals]

I've been tending it and checking voltage constantly in case low voltage cut off doesn't work.

I think its far more common that a single cell hits low voltage cutoff (hopefully not below 2.5V) rather than battery voltage. It sounds like you do not have access to cells to check cell voltage. So your discharge test would likely only reveal battery voltage when a single cell hits low voltage.

Maybe this us useful for your peace of mind.

This is cheapo sealed lifpo4.

Which cheap LiFePO4? Link?

 

[kytoon]

It was one Will ripped apart figuratively and literally. Lugs were soldered not crimped and the leads were soldered to bus bars. After wills review, they reportedly changed the soldering and actually went to bolted bus bars and crimped leads per tear downs that happened afterwards by others. Who knows if this was real or if I got the old left over stock. It was the cheapest one on amazon with low temp cut off. I had $150 amazon gift cards so I got it for $140. I know it still cost me $290 but I could rationalize it at $140. Since my purchase they have raised the price.