5 Channel application matching of battery cells for large-scale storage

• Determination of series resistance (electrolyte) and parallel resistance (electrodes) by impedance measurement at previously set frequencies
• Additive measurement of cell voltage and temperature
• Up to 5 measuring channels per device
• Parameterization of the measurement parameters via PROFINET

Task

Many round cells are often used in battery operated large-scale storage systems. Before these are installed, different battery parameters of each individual cell must be exactly and quickly measured and evaluated in order to achieve qualitative matching. The contacting of the round cells takes place using the four-conductor measuring method (for each current and voltage cable). The two-frequency impedance measurement is used to determine the series resistance (electrolyte) and the parallel resistance (electrodes). In parallel to this, the respective cell voltage and temperature are recorded and evaluated. At the control side, the data is passed over via PROFINET. All measuring and evaluation data is archived for traceability.

Measuring and evaluation parameters
U_cell .................... ≈ 0 … 3.3 to 3.8 VDC
R_AC (1 kHz) ....... ≈ 23.50 … 24.88 mΩ
R_DC (10 Hz) ....... ≈ 24.71 mΩ
ϑ ........................ ≈ 22 … 28 °C