Data for:Resolving inter-cell heterogeneity to mitigate degradation amplification in battery packs

This dataset accompanies the manuscript "Resolving inter-cell heterogeneity to mitigate degradation amplification in battery packs". It contains paired cell-level and pack-level battery aging data from both laboratory-controlled experiments and real-world field measurements. Covering two battery chemistries, LiFePO4 and NMC, the dataset includes 34 cells and 22 packs across 13 operating protocols. Operating conditions span C-rates from 0.3C to 12.5C and temperatures from 20 °C to 55 °C. Rare paired aging trajectories are provided for cells and packs assembled from the same battery batches, enabling direct analysis of cross-scale degradation transfer and pack inconsistency evolution. By linking laboratory aging tests with field measurements from grid-storage packs, the dataset supports research on pack-level SOH estimation, degradation modeling, and battery health management. Four cell-pack pairs are included: ESSL1: LiFePO4, nominal cell capacity of 102 Ah, 6 laboratory cells and 1 laboratory pack, with a 16s pack structure. ESSL2: LiFePO4, nominal cell capacity of 105 Ah, 16 laboratory cells and 1 laboratory pack, with a 15s pack structure. ESSH1: LiFePO4, nominal cell capacity of 302 Ah, 4 laboratory cells, 2 laboratory packs with 16s and 52s pack structures, and 16 field packs with 416s pack structures. PBSL1: NMC, nominal cell capacity of 4 Ah, 8 laboratory cells and 2 laboratory packs, with a 15s pack structure. Most files are stored in Python pickle format .pkl and can be loaded using pandas.read_pickle()(pandas==1.3.5) or the loading scripts provided in the associated GitHub repository. Associated code is available at: https://github.com/BatICM/cell-to-pack-degradation BatICM/cell-to-pack-degradation: Code for: State-space geometry drives degradation amplification in battery packs ESSL1 is included in the GitHub repository as a lightweight example, while the complete datasets are provided in this Zenodo record. A detailed description of the dataset structure and usage will be provided in the supplementary information of the publication.