Charging parameters for two 12 volt batteries in 24 volt configuration?

[PaintBrush]

What are the charging parameters for eight Battery Hookup LiFePO4 100ah modules in 8S (creating equivalent of two: 12 volt batteries) in 24 volt configuration with a 24-volt BMS? Do the batteries get charged as 12 volt, or 24 volt?
Or am I confused?

 

[sunshine_eggo]

What are the charging parameters for eight Battery Hookup LiFePO4 100ah modules in 8S (creating equivalent of two: 12 volt batteries) in 24 volt configuration with a 24-volt BMS? Do the batteries get charged as 12 volt, or 24 volt?
Or am I confused?

This. The only reason I can think you are confused is that you're familiar with marine systems charging where they commonly use a specialized charger to charge two 12V in series as two 12V instead of one 24V battery.

You don't have two 12V batteries or a 24V battery. You have an 8S LFP battery, so it should be charged accordingly.

8S LFP is 25.6V nominal. That is a good replacement for a 24V Lead-acid system.

You charge your LFP 8S battery to:
Absorption: 27.6-28.8V (3.45 - 3.55V/cell) - low end less stressful to the cells and requires a long absorption phase and will charge to about 98%+, but high end charges quickly and requires short absorption phase.
Float: 27.2V (3.40V - cell) - note that even at the float voltage, an LFP battery will continue to charge until about 95% full.

 

[PaintBrush]

This. The only reason I can think you are confused is that you're familiar with marine systems charging where they commonly use a specialized charger to charge two 12V in series as two 12V instead of one 24V battery.

You don't have two 12V batteries or a 24V battery. You have an 8S LFP battery, so it should be charged accordingly.

8S LFP is 25.6V nominal. That is a good replacement for a 24V Lead-acid system.

You charge your LFP 8S battery to:
Absorption: 27.6-28.8V (3.45 - 3.55V/cell) - low end less stressful to the cells and requires a long absorption phase and will charge to about 98%+, but high end charges quickly and requires short absorption phase.
Float: 27.2V (3.40V - cell) - note that even at the float voltage, an LFP battery will continue to charge until about 95% full.

OK, thanks for clearing this up for me. I looked all over for the answer before posting and could not find it.