The Developments And Applications Of Multi-scale Lithium Ion Battery Models Based On Dynamic Responses

Abstract:The existing of multi-scales and multi-physics makes the research and development of battery face the difficulty that the common experimental methods can’t evaluate the battery behavior with high efficiency and low cost. In this thesis, the2.3Ah,26650cylindrical type lithium iron phosphate battery was investigated. The multi-scales lithium ion battery models for the battery were developed and applied taking dynamic responses into account. These can provide the based theory for battery design and widen the application fields of electrochemical simulation.1. In view of the insufficiency and poor self-adaptability of battery models caused by the variety of materials and multi-physics effects, material dynamic responses was put forward as the material library of the models. The dynamic parameters related to electrolyte and electrodes were analyzed with emphasis, then the foundation method and function mechanism of material dynamic responses were suggested.2. Based on the material dynamic responses, the pseudo two-dimensional model (P2D model) was developed. The simulation results with the model show good agreement with experimental results. With this model, the pulse and constant current discharge behavior were studied.3. Based on the material dynamic responses, the single particle model (SP model) was developed. With this model, the methods for improving battery performance including particle radius optimization and solid diffusion optimization were studied. Compared with the P2D model, the SP model is more efficient in calculating.