Nickel-Zinc Cell Modelling on a Continuum Scale

Kurzfassung

The growing demand for electric power coupled with the significance of renewable energy sources underscores the need for cost-effective, reliable, and sustainable storage solutions. Zinc-based batteries represent an innovative approach, offering advantages through their use of abundant, inexpensive materials that are environmentally friendly, recyclable, and non-flammable [1,2]. The nickel-zinc (Ni/Zn) battery emerges as a particularly promising candidate for stationary energy storage applications. However, a complete understanding of the physicochemical processes during operation remains incomplete, challenging efforts to achieve consistent performance. Critical issues affecting efficiency and longevity include zinc electrode shape change, compaction leading to reduced pore volume and gas production impacting electrolyte levels. Building upon lithium-ion battery modelling approaches [3], we have developed a 3D+1D continuum model incorporating thermodynamic principles and volume averaging techniques [4]. This model enables detailed real-time analysis of transport phenomena and electrochemical reactions during Ni/Zn cell cycling. The three-dimensional simulations reveal temporal redistribution patterns of phases (e.g. zinc) and chemical constituents throughout the cell, while the additional dimension focuses on particle-level solid diffusion processes. By comparing simulation results with experimental data, the quality of the model is assessed. We demonstrate and discuss the capabilities of our approach, which can serve as a valuable tool for optimising the cell regarding performance and cycle life. Acknowledgements: This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 963576 (LoLaBat – Long Lasting Batteries). References: 1. J. McBreen, J. Power Sources, 1994, 51, 37-44. 2. T. B. Reddy, Linden’s Handbook of Batteries, McGraw-Hill, New York, NY, 4th edn., 2011. 3. A. Latz, J. Zausch, J. Power Sources, 2011, 196, 3296-3302. 4. T. Schmitt, T. Arlt, I. Manke, A. Latz, B. Horstmann, J. Power Sources, 432, 119-132.