Pretrained battery transformer (PBT): A foundation model for battery life prediction

Early prediction of battery cycle life is essential for improving battery design, manufacturing and deployment. However, despite encouraging progress with machine learning, battery life prediction remains constrained by scarce data and pronounced heterogeneity across battery chemistries, specifications, formation protocols and operating conditions. Although transfer learning has been widely explored to alleviate these challenges, its effectiveness is limited by the absence of a foundation model that can integrate heterogeneous battery life data and provide broadly useful knowledge for target-scenario specialization. Here we introduce the pretrained battery transformer (PBT), a foundation model for battery life prediction that incorporates battery-knowledge-encoded mixture-of-experts layers to learn from scarce and heterogeneous lifetime data. PBT is first pretrained on 13 lithium-ion battery datasets to yield a general PBT that encodes comprehensive battery lifetime knowledge, and is then adapted through transfer learning into specialized PBT models for target scenarios. Across 15 datasets covering 977 batteries and 528 sets of aging conditions from lithium-ion, sodium-ion and zinc-ion batteries, PBT achieves state-of-the-art performance, surpassing the strongest competing method by 21.9% on average, with gains of up to 86.9%. This study establishes, to our knowledge, the first foundation model for battery life prediction and provides a step towards shifting battery lifetime prediction from isolated, scenario-specific modelling tasks to a reusable knowledge foundation that can be specialized to target scenarios with limited data, with implications for other prediction problems characterized by scarce and heterogeneous data in sustainable energy.