Akkuzustand

Akkuzustand, commonly referred to as state of charge (SoC) in English, describes the current amount of usable energy stored in a rechargeable battery relative to its nominal capacity. It is typically expressed as a percentage, where 0% means the battery is depleted and 100% indicates it is full. The concept is central to battery management in applications such as electric vehicles, consumer electronics, and stationary energy storage.

Estimating the Akkuzustand involves several methods. Direct voltage measurement is simple but depends on battery chemistry and state of charge, and can be unreliable near the ends of the range. Coulomb counting integrates the current flowing into and out of the cell to track charge over time, requiring knowledge of the cell’s capacity and occasional recalibration. Model-based approaches use mathematical or data-driven estimators, such as Kalman filters or machine learning models, to fuse voltage, current, temperature, and aging information for a more accurate SoC estimate. All methods must account for temperature effects, aging, and battery history, which can alter capacity and internal resistance.

The Akkuzustand is a key input for control systems and user information, informing operations, safe charging policies, and range forecasts. It is often complemented by related notions such as state of health (SoH), which indicates remaining battery life and degradation, and state of power (SoP), which describes available current capability. Estimation accuracy can vary with operating conditions and battery aging, so calibrations and robust sensing are important for reliable SoC reporting.