battery-pack-LFP-dat

Build

Cells Configurations
16 48V 15A
20 60V 15A
24 72V 15A
32 48V 30A
40 60V 30A
48 72V 30A, 48V 45A
60 60V 45A
72 72V 45A

pack 32140

pack design

4x4

4x8 or 4x10

4x8 == 48V 30A

16S

1. Voltage Specifications Matrix

Because LFP voltage profiles shift based on charge state and current load, configurations must align with the three primary operational thresholds:

Parameter State Per Cell Threshold Total 16S Pack Voltage Engineering & BMS Logic
Maximum Charge Cut-off 3.65 V 58.4 V Absolute high-voltage ceiling. BMS must trip if any single cell touches 3.65V.
Nominal Rating 3.20 V 51.2 V Standard baseline used for calculating pack system capacity (Wh = Ah × 51.2V).
Discharge Cut-off (Empty) 2.50 V 40.0 V Absolute low-voltage floor. BMS must disconnect loads to prevent copper plating/permanent damage.

2. Resting Voltage vs. State of Charge (SoC)

Due to the characteristic flat discharge curve of $LiFePO_4$ chemistry, open-circuit voltage (OCV) remains highly stable throughout the mid-range of capacity. The following values reflect a settled, resting 16S pack (no load, no charge for at least 30 minutes):

  • 100% SoC: ~54.4 V to 56.0 V (Surface charge dissipates rapidly down from 58.4V once charging terminates)
  • 90% SoC: ~53.3 V
  • 70% SoC: ~52.5 V
  • 50% SoC: ~51.5 V
  • 30% SoC: ~51.3 V
  • 10% SoC: ~50.4 V (The curve begins its sharp downward knee here)
  • 0% SoC: 40.0 V to 44.0 V (Voltage drops off a vertical cliff under load)

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