State of Charge (SOC) Algorithm

The AES battery cabinet system uses a multi-method SOC algorithm to ensure high accuracy and reliability in determining the State of Charge (SOC).

SOC Calculation Methods

1. Coulomb Counting (Method #1)

   • Active when the battery is charging or discharging (current ≠ 0).

   • Tracks the charge in and out of the battery in real-time to calculate SOC.

2. Voltage-Based Lookup Table (Method #2)

   • Activated when the battery has been idle (0 A current) for more than 2 hours.

   • Estimates SOC based on resting voltage using a predefined lookup table.

   • SOC adjustments using this method are limited to decreases only to prevent inaccuracies.

SOC Maintenance & Calibration

• To maintain SOC accuracy, the battery must complete a full charge or discharge cycle every two weeks.

• This process prevents SOC drift and ensures proper calibration of the algorithm.

Voltage-Based SOC Reference Points

• 100% SOC = 3.55 V per cell (average)

• 0% SOC = 2.8 V per cell (average)

This multi-method approach ensures precise SOC monitoring under various operating conditions, improving system performance and reliability.