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In order to increase the performance of the Energy Management System (EMS) for the M5BAT (Modular Multi-Megawatt Multi-Technology Middle Voltage Battery Storage System), with a size of 5 MW and to take full economic advantage of the various lead-acid batteries, battery models are implemented. Based on such models, a technology specific and favorable operation can be assured. For improving the model an experimental study of gassing has been conducted on the Sonnenschein A602 OPzV VRLA (gel) battery. Single electrode potentials have been observed and evaluated at different current rates at a regulated temperature of 25°C. Parameters such as the symmetry factor and current exchange density have been obtained from the measured data. Matlab/Simulink has been used to model the process of gassing using Tafel´s equations.
 J. Fleer and P. Stenzel, “Impact analysis of different operation strategies for battery energy storage systems providing primary control reserve,” Journal of Energy Storage, vol. 8, pp. 320–338, Nov. 2016.
 D. H. Doughty, P. C. Butler, A. A. Akhil, N. H. Clark, and J. D. Boyes, “Batteries for largescale stationary electrical energy storage,” The Electrochemical Society Interface, vol. 19, no. 3, pp. 49–53, 2010.
 S. S. Misra, S. L. Mraz, J. D. Dillon, and D. B. Swanson, “VRLA Battery with AGM-gel hybrid for superior performance” in Proceedings of The 25th International Telecommunications Energy Conference, 2003, pp. 378–382.
 M5BAT. (2016, Sep.). M5BAT: A Unique Hybrid Battery Storage System. M5BAT. Aachen, Germany [Online]. Available: http://m5bat.de/en-gb/
 D. Berndt, “Valve-regulated Lead-acid batteries,” Journal of Power Sources, vol. 100, pp. 29–46, 2001.
 D. Berndt, Maintenance-Free Batteries: Based on Aqueous Electrolyte Lead-Acid, Nickel/Cadmium, Nickel/Hydride; A handbook of battery technology, 3rd ed., Taunton, UK: Research Studies Press, 2003.
 D. Linden and T. B. Reddy, Handbook of Batteries, 3rd ed., New York: McGraw-Hill, 2002.
 D. U. Sauer, “Optimierung des einsatzes von blei-säure-akkumulatoren n photovoltaikhybrid-systemen unter spezieller berüksichtigung der batteriealterung,” Ph.D. dissertation, Dessertation, University of Ulm, Germany, 2003.
 A. Hammouche, M. Thele, and D. U. Sauer, “Analysis of gassing processes in a VRLA/spiral wound battery,” Journal of Power Sources, vol. 158, pp. 987–990, 2006.
 M. Thele, A Contribution to the Modelling of the Charge Acceptance of Lead-acid Batteries: Using Frequency and Time Domain Based Concepts. Aachen, Germany: Shaker Verlag Gmbh, 2008.
 H. Bode, Lead-acid Batteries. New York: Wiley, 1977.