Analysis of the Model Dynamics for the Battery and Battery Converter in a Grid Connected 5 kW Photovoltaic System

The high demand for large lithium-ion (li-ion) batteries is mainly driven by applications with long system life times such as photovoltaic (PV) systems with integrated battery storage and electrification of automotive applications. In order to generate reliable life cycle cost (LCC) estimations long term simulations are necessary. To increase simulation speed the general approach for long term simulations is to simplify the simulation models e.g. by reducing the model dynamics. In this paper the simulation error made by model simplification will be analyzed and the effect on LCC estimations will be discussed qualitatively. Finally requirements for the model dynamics, in particular the battery model and the converter model, are discussed. The example of the PV-battery system developed within the Franco-German Sol-ion project will be used for consideration.