Steve_S
Offgrid Cabineer, N.E. Ontario, Canada
A reminder on a few points.
1) Charge a cell to 3.650 and allow to saturate till <2A is being taken. One hour rest will see it settle to 3.550 +-0.050, more likely closer to 3.500.
2) The primary voltage curve of LFP is 3.000-3.400, there is very little AH below or above these voltage. Remember LFP settles.
3) The NOMINAL voltage is 3.200 and that is where the Watt Hours are calculated. 3.2V*280AH=896Wh per cell * #ofCells (4)=3584, (8)=7168, (16)=14,336
4) Temperature DOES affect Charge & Discharge capacities. Nominal Test temperatures is 25°C/77°F
You can charge LFP cells to 3.650 until amps taken is ZERO and even leave it there for 24hrs charging at that rate, within an hour of power being removed they will settle to 3.500-3.550, within 12 hours they will sit around 3.450 without any charge going it. This is Completely Normal for this chemistry.
The Bulk Commodity ESS cells will vary much more and generally diverge somewhat above 3.400 and below 3.000 and that can be as much as 1mv per AH of capacity.
There are some links in my signature which would help you related to ESS Cells, Voltage Curves and such.
Hope it helps, Good Luck.
1) Charge a cell to 3.650 and allow to saturate till <2A is being taken. One hour rest will see it settle to 3.550 +-0.050, more likely closer to 3.500.
2) The primary voltage curve of LFP is 3.000-3.400, there is very little AH below or above these voltage. Remember LFP settles.
3) The NOMINAL voltage is 3.200 and that is where the Watt Hours are calculated. 3.2V*280AH=896Wh per cell * #ofCells (4)=3584, (8)=7168, (16)=14,336
4) Temperature DOES affect Charge & Discharge capacities. Nominal Test temperatures is 25°C/77°F
You can charge LFP cells to 3.650 until amps taken is ZERO and even leave it there for 24hrs charging at that rate, within an hour of power being removed they will settle to 3.500-3.550, within 12 hours they will sit around 3.450 without any charge going it. This is Completely Normal for this chemistry.
The Bulk Commodity ESS cells will vary much more and generally diverge somewhat above 3.400 and below 3.000 and that can be as much as 1mv per AH of capacity.
There are some links in my signature which would help you related to ESS Cells, Voltage Curves and such.
Hope it helps, Good Luck.