Experimental LiFePO4 Battery Cycling System. Analysis and Simulation of a stand-alone/on-grid Photovoltaic Applications.
J.S. Artal-Sevil, J.M. Lujano-Rojas, R. Dufo-López, J.L. Bernal-Agustín, J.A. Tejero-Gómez Department of Electrical Engineering. Higher Technical School of Industrial Engineering. University of Zaragoza. Campus Río Ebro – Zaragoza 50018 (Spain). 2025-07-25

Abstract

This paper presents the design, modeling, and validation of an experimental LiFePO4 battery cycling system applied to stand-alone and on-grid photovoltaic (PV) scenarios. A comprehensive analysis of battery behaviour -including key parameters such as SOC, SOH, DOD, and internal resistance- is conducted to highlight the advantages of LiFePO4 chemistry in terms of safety, thermal stability, and cycle life. The charge/discharge dynamics are governed by the CCCV protocol, with detailed insights into voltage plateau behaviour, degradation mechanisms, and second-life reuse potential. The proposed experimental platform integrates a programmable power supply, active load, and full monitoring system to simulate real irradiance and consumption profiles with high temporal resolution. Results from the test-bench validate the accurate tracking of SOC, power flow optimization, and effective battery cycling under fluctuating PV conditions. Colour-map diagrams and hourly data analyses demonstrate the system’s capacity to balance generation, storage, and consumption, ensuring reliability and autonomy. The setup also enables the modeling of thermal and electrical behaviour at minute-level resolution, offering a valuable tool for the simulation and development of distributed PV-battery storage systems. The energy balance analysis, based on minutely power data, confirms the model’s accuracy in simulating real-world PV-battery interactions.

Key words: Battery Cycling System, LiFePO4 Battery, Battery charge/discharge, SOC/SOH estimation, BMS, stand-alone/on-grid Photovoltaic Power System.

References

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