Battery SOC-OCV Lookup Table Optimization

This demo includes pseudo-OCV data collected from various commercial cylindrical Lithium-ion cells. A dynamic programming optimization approach is implemented to determine the optimal placement of SOC-OCV lookup table (LUT) breakpoints. The following cells are included:

Cell Model	Test Condition
Molicel INR21700P42A	C/32 discharge-charge at room temperature.
Lithium Werks APR18650M1B	C/32 discharge-charge at room temperature.
Samsung INR2170040T	C/20 charge-discharge at room temperature.
Molicel INR18650P28A	C/20 charge-discharge at room temperature.
Molicel INR1800P28A	C/32 discharge-charge at room temperature.

The figures below plot the optimized SOC-OCV LUT breakpoints alongside the corresponding pseudo-OCV curves.

SOC OCV 0.0000 2.5061 0.0151 2.8981 0.0452 3.1461 0.0955 3.3231 0.1508 3.4218 0.2915 3.5737 0.4573 3.7017 0.8342 4.0637 0.9497 4.1009 1.0000 4.1932

SOC OCV 0.0000 2.0102 0.0033 2.4177 0.0117 2.7405 0.0267 2.9299 0.0534 3.0872 0.0885 3.1942 0.2972 3.2772 0.9833 3.3511 0.9950 3.4180 1.0000 3.5981

SOC OCV 0.0000 2.5000 0.0050 2.8080 0.0352 3.1179 0.0854 3.3182 0.1357 3.4193 0.2915 3.5826 0.4523 3.6941 0.8392 4.0664 0.9548 4.1121 1.0000 4.2000

SOC OCV 0.0000 2.7027 0.0201 3.0068 0.0452 3.1736 0.0905 3.3275 0.1457 3.4287 0.2814 3.5700 0.4573 3.6972 0.8442 4.0595 0.9548 4.1108 1.0000 4.1881

SOC OCV 0.0000 2.5199 0.0151 2.9068 0.0452 3.1409 0.1106 3.3301 0.1809 3.4544 0.3116 3.5860 0.4824 3.7012 0.8492 4.0666 0.9598 4.1238 1.0000 4.1943

BibTeX

If you find this repo useful in your research, please cite:

@article{sunil2025piecewise,
  title={Piecewise Linear Approximation of Battery Open-Circuit Voltage Characteristics Using Dynamic Programming},
  author={Sunil, Sooraj and Pattipati, Krishna R and Balasingam, Balakumar},
  journal={IEEE Transactions on Instrumentation and Measurement},
  year={2025},
  publisher={IEEE}
}