Sensor minimal cell monitoring with integrated direct active cell balancing

The presented paper introduces a sensor minimal battery observer, which allows the equipping of each stack with only one voltage and one current sensor, without losing the required individual cell measurement. The individual cell measurement is required not only for many Li-Ion applications with cell chemistry that can result in exothermic reactions. For a stack with 12 cells this can results in a reduction of up to 22 voltage and current sensors. Despite the measuring feature, the presented concept includes an active balancing method. This balancing method offers reduced impact on the battery cells while allowing highly efficient energy balancing without a separate cell connection.