Managed vs Unmanaged Batteries and How SOC Works

Managed vs Unmanaged Batteries and How SOC Works

State of Charge (SOC) indicates the remaining capacity of a battery as a percentage. How SOC is calculated and reported depends on whether the battery is managed or unmanaged.


Managed Batteries:

  • Examples: BSL, Pylontech, Sungrow

  • These batteries include a Battery Management System (BMS) that directly reports SOC to the inverter.

  • The SOC reading is precise and cannot be recalibrated manually.

  • If a sudden drop in SOC occurs, it typically indicates a hardware fault, communication error, or monitoring issue, not a calibration problem.


Unmanaged Batteries:

  • Example: PowerPlus

  • These do not report actual SOC. Instead, SOC is assumed based on voltage and system behavior.

  • SOC values on unmanaged batteries can fluctuate unexpectedly.

  • Recalibration may help in aligning estimated SOC with real-world performance, but accuracy is limited.


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