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Battle born low voltage shut down

Strawberry Garcia

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Oct 30, 2020
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I was testing my battle born to see how long I could operate my RV and it went into low-voltage shut down I have a Renolgy voyager charge controller on my solar panel that supposed to be able to restart a lithium when it’s in low-voltage shut down mode nothing happening so far anybody with ideas? Thank you
 
Just curious... What's the voltage reading of your BB in "shut down" mode? I sent mine into some sort of shutdown when I was fumbling with my anderson connectors. Mine read somewhere between 5-6 volts (can't remember exactly). But, I just hooked up my NOCO GENIUS10 AC charger and it came right back up to normal almost immediately...
 
If charging working you should see voltage at battery terminals.

The battery will initially charge at low rate so you may have to wait some time before it charges up enough to reset its BMS low voltage disconnect.
 
I am running into a similar situation. My two BB also over discharged I believe. Now when I try charging them the charging voltage will go up into the high 14 to low 15 volt range shutting down my charger. The batteries will then settle around 13.2 Volts. When I throw any type of draw at them the batteries instantly drop to 10.5V. I currently have my Powermax converter throttled back to 13.2V trying to keep it from triggering the BMS and seeing if the battery will take a charge that way. Any help on a better way or a proper way to revive these would be appreciated. One is 2 years old and the other is less than 6 months.
 
Some chargers and inverter/chargers have a problem 'reawakening' a low voltage cutout tripped BMS. The BMS blocks any further discharge but turns on a path for reverse current charging.

There is typically a diode and a power resistor to limit the initial charging current which is a safety requirement for an over discharged lithium battery. Once all the cells gets above about 3v the BMS bi-directional switch reengages resetting the BMS.

Because of the initial high path resistance, due to diode and power resistor, the voltage as it appears to the charger rises quickly faking out the charger to believing the battery is defective. If charger just drops back to float voltage the battery will charge and eventual reset the BMS cutout. Some chargers are 'smart' and detect an abnormally fast voltage rise as a bad battery and just terminates charging.

An inverter/charger that actually has a Lithium Ion battery setting option may truncate charging when battery voltage seen by charger hits the maximum charge voltage, again termination charge current before battery has gotten enough charge to reset BMS. The inverter/charger may recycle a new charging cycle and eventually the battery will reset BMS.

Some inverters just sit in idle mode when battery voltage lost and/or reapplied, waiting for user to manually tell it what to do. Actually I prefer this as it forces you to determine the cause of what should be classified as an abnormality.

There are a few inverter/chargers that will totally shut down if battery voltage lost so no charging and you are really F'd if you have this situation.

If you find yourself in this situation a CV/CC limited power supply will get the BB battery to charge and re-engage BMS.

This is why you should carefully set inverter low voltage shutdown so it trips before battery BMS. Having too much battery cable resistance makes this very difficult when heavy inverter loading causes voltage drop at inverter input terminals.
 
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Don't BBBs have low voltage protection? About your inverter?
 
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