From Static Spectra to Operando Infrared Dynamics: Physics Informed Flow Modeling and a Benchmark
Organizations: Department of Information Engineering, The Chinese University of Hong Kong · Shenzhen Loop Area Institute · Massachusetts Institute of Technology · Department of Computer Science and Engineering, The Hong Kong University of Science and Technology
Abstract
The Solid Electrolyte Interphase (SEI) is critical to the performance of lithium-ion batteries, yet its analysis via Operando Infrared (IR) spectroscopy remains experimentally complex and expensive, which limits its accessibility for standard research facilities. To overcome this bottleneck, we formulate a novel task, Operando IR Prediction, which aims to forecast the time-resolved evolution of spectral ``fingerprints'' from a single static spectrum. To facilitate this, we introduce OpIRSpec-7K, the first large-scale operando dataset comprising 7,118 high-quality samples across 10 distinct battery systems, alongside OpIRBench, a comprehensive evaluation benchmark with carefully designed protocols. Addressing the limitations of standard spectrum, video, and sequence models in capturing voltage-driven chemical dynamics and complex composition, we propose Aligned Bi-stream Chemical Constraint (ABCC), an end-to-end physics-aware framework. It reformulates MeanFlow and introduces a novel Chemical Flow to explicitly model reaction trajectories, employs a two-stream disentanglement mechanism for solvent-SEI separation, and enforces physics and spectrum constraints such as mass conservation and peak shifts. ABCC significantly outperforms state-of-the-art static, sequential, and generative baselines. ABCC even generalizes to unseen systems and enables interpretable downstream recovery of SEI formation pathways, supporting AI-driven electrochemical discovery.
Figures & tables
| Dataset | Scale | Ratio Label | Openness | ML-Ready | Real-World | Sequential | Benchmark | Evaluation |
|---|---|---|---|---|---|---|---|---|
| Ellis et al. (2018) | 81 | ✓ | ✗ | ✓ | ✓ | ✗ | ✗ | ✗ |
| Meyer et al. (2023) | 1,000 | ✓ | ✗ | ✓ | Simulation | ✗ | ✗ | ✗ |
| Buteau et al. (2019) | 40 | ✓ | ✓ | ✓ | ✓ | ✗ | ✗ | ✗ |
| Buteau et al. (2019) (robot) | 300 | ✗ | ✓ | ✓ | ✓ | ✗ | ✗ | ✗ |
| Kim and Hallinan (2020) | 6 | ✓ | ✗ | ✗ | ✓ | ✗ | ✗ | ✗ |
| Ours | 7,118 | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
| Method | MAE ( ) | MSE ( ) | RMSE ( ) | SAM( ∘ ) | CosSim | DILATE | |
|---|---|---|---|---|---|---|---|
| IR spectrum generation (static): | |||||||
| NNMol-IR | 11.21\text{\scriptsize\pm 1.04} | 20.3\text{\scriptsize\pm 2.9} | 14.18\text{\scriptsize\pm 1.32} | 89.26\text{\scriptsize\pm 6.66} | 0.013\text{\scriptsize\pm 0.115} | -3.89\text{\scriptsize\pm 2.74} | |
| MACE4IR | 8.98\text{\scriptsize\pm 1.15} | 13.7\text{\scriptsize\pm 3.3} | 11.62\text{\scriptsize\pm 1.42} | 89.38\text{\scriptsize\pm 9.12} | 0.011\text{\scriptsize\pm 0.167} | -2.28\text{\scriptsize\pm 1.90} | |
| Video generation: | |||||||
| CogVideoX | 7.77\text{\scriptsize\pm 1.16} | 10.9\text{\scriptsize\pm 2.8} | 10.33\text{\scriptsize\pm 1.36} | 90.74\text{\scriptsize\pm 9.40} | -0.013\text{\scriptsize\pm 0.162} | -1.52\text{\scriptsize\pm 0.68} | |
| Pyramid-Flow | 5.67\text{\scriptsize\pm 0.85} | 6.8\text{\scriptsize\pm 1.5} | 7.65\text{\scriptsize\pm 0.93} | 51.29\text{\scriptsize\pm 5.64} | 0.573\text{\scriptsize\pm 0.073} | -0.70\text{\scriptsize\pm 2.04} | |