LifePo4 Voltage at .5C - .6C Discharge
Our two GC2's (with 100% charge) drop below 12v while under a 100a - 125a load. When they reach 50% (at 100a - 125a), voltage drops into the low 11's while under-load. What kind of under-load volt...
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I am not sure what your obsession with this is, but as we have tried to explain before, you cannot use voltage to determine the SOC for a lithium battery. Anyone who with experience with lithium batteries knows this.
Look at the discharge curve posted earlier in this thread - as soon as you use an LiFePO4 cell it will drop to ~3.3V/cell (or ~13.2V for 4 cell pack) at around 98% SOC and will stay there until ~10% SOC.
At a 1C discharge rate each cell will be about 3.25V, or 13V for the pack, so the Lifeblue BMS/wiring is dropping about 0.3V at 100A, or 3mOhm. At 15% SOC and 1C the cell voltage is ~3.1V, so the pack would be 12.4 - 0.3V for wiring = 12.1V. Right on with OTRs estimate.
Look at the discharge curve posted earlier in this thread - as soon as you use an LiFePO4 cell it will drop to ~3.3V/cell (or ~13.2V for 4 cell pack) at around 98% SOC and will stay there until ~10% SOC.
At a 1C discharge rate each cell will be about 3.25V, or 13V for the pack, so the Lifeblue BMS/wiring is dropping about 0.3V at 100A, or 3mOhm. At 15% SOC and 1C the cell voltage is ~3.1V, so the pack would be 12.4 - 0.3V for wiring = 12.1V. Right on with OTRs estimate.
