SIT Large-Format LiFePO4 Battery Degradation Dataset (50 Ah Prismatic Cells)

This dataset contains electrochemical and thermal ageing measurements for 22 large-format prismatic lithium iron phosphate (LiFePO₄) cells (50 Ah, 3.2 V nominal) collected at the Singapore Institute of Technology (SIT) over an approximately 18-month campaign. Cells were cycled on industrial battery testers (Repower and Chroma) under multiple conditions: full charge/discharge deep cycling at 1C and 2C current rates, partial micro-cycling centred at 50% state of charge, and two thermal environments (ambient and 40 °C controlled chamber). Up to 878 cycles per cell were recorded, producing approximately 14,800 data files.Each simplified cycle file is an Excel workbook with separate Charge and Discharge sheets containing six signals at 1-second resolution: voltage (V), current (A), accumulated capacity (Ah), accumulated energy (Wh), time (s), and surface temperature (°C, 1–2 thermocouple channels per cell). Per-cell capacity summary CSV files enable direct capacity fade tracking. Standalone temperature records and micro-cycling files are provided separately. Under identical 1C ambient conditions, capacity retention after ~800 cycles ranges from 6.7% to 87.6% across ten cells, capturing the substantial cell-to-cell variability found in practice.The dataset is released to support battery degradation analysis, state-of-health estimation, remaining useful life prediction, machine learning model development, and cross-condition benchmarking. A Python loader library and Jupyter notebooks are included in the accompanying Code directory.