Novel Reduced-Order Electrochemical Models for Lithium-Ion Batteries Integrating Comprehensive Degradation Mechanisms across Various Operational Scenarios

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It is crucial to enhance the computational efficiency while ensuring accuracy in battery simulations, particularly given the presence of degradation factors. We propose reduced order electrochemical models, including a revised single-particle model (RSPM) and fast-calculating P2D (FCP2D) model. They use shape functions to model the lithium-ion concentration and electrolyte potential distribution, and apply the weak form to construct equations for solving the time-dependent polynomial parameters. These two reduced-order electrochemical models have incorporated comprehensive side-reactions, including the anode SEI formation and evolution, anode transitional metal reduction, cathode SEI formation and evolution, cathode film formation and evolution, cathode transitional metal dissolution, and electrolyte oxidation. The performances of the reduced order models are evaluated by comparing the simulation results with those generated by the P2D benchmark model during constant current charging/discharging single cycle, random C-rate operation mode, and dynamic charging/discharging cycling. Results show that the RSPM and FCP2D models can predict the battery performance (e.g., terminal voltage, salt concentration, electrolyte potential) and degradation (e.g., the current density of each side-reaction, the concentration of side-reaction species, cell capacity degradation) accurately and efficiently. The relative error is below 10% while the RSPM and FCP2D demonstrate a much higher calculation efficiency than the P2D benchmark model, with a calculation speed up to ten times faster.