Using an RV Converter as a Charger

[snoobler]

That converter will work great... fast charge to 14.4V and float. Negligible absorption time. Battery should top out at 95% max.

 

[grizzzman]

That converter will work great... fast charge to 14.4V and float. Negligible absorption time. Battery should top out at 95% max.

Don't hold you're breath......will likely never see 14.4. Most RV's wiring won't allow more then 30ish amps and the WFCO needs very low voltage for it to apply 14.4. lack of lifepo4 voltage sag means no 14.4.......

 

[snoobler]

Even so, a multi hour float at 13.6 will hit 90-95%.

 

[smileyman57]

Follow-up question: there is a Lithium option WF-9800LiS and the charge profile is below.
Might be a silly question but it states that at a minimum the Bulk mode will run for an hour. There is no real risk to LFP batteries with this profile is there? i.e. batteries are charged, plug the RV to shore power and they are subjected to the 1hr bulk.

If I know they are charged I could always flip the breaker to turn off the converter.

I think for now I will build the battery and test with my current Converter. Thanks for all the feedback thus far!

WF-9800LiS converter:

 

[snoobler]

Agree. Test with what you have. The drop to 13.2 isn't an issue.

 

[mkaye]

Even so, a multi hour float at 13.6 will hit 90-95%.

when i look at the charging curves, i see 40-60% SOC for 13.6V (3.4V/cell)

 

[snoobler]

when i look at the charging curves, i see 40-60% SOC for 13.6V (3.4V/cell)

SoC and voltage are current dependent. Most charge curves indicate a charge current as well. If you deviate from that current you won't have the same relationship.

Bottom line is if you are floating LFP at 13.6V (3.4V/cell), you will attain 90-95% SoC because the cell will continue to absorb current.

See the chart in this post:

Lishen cells: charge profile for 15 - 85 % SOC

My 280ah Lischen cells are in 16s configuration and I will be put into service soon on my 5,500 watt off grid inverter. My charging does not go through my Orion BMS so I need to be specific with my charge setting. I'd like to keep things between 15 -85 % SOC since I don't need anywhere close...

diysolarforum.com

Better to count current than rely on a voltage.