Conference Agenda

High-fidelity simulations of lithium-ion batteries are often limited by the high computational cost associated with fully resolved three-dimensional (3D) multi-physics models. This work presents a hybrid 3D–1D framework for simulating a large-format 4680 cylindrical lithium-ion cell by coupling a one-dimensional electrochemical model with a three-dimensional thermal representation of the jellyroll. To ensure the physical reliability of the core governing equations, the baseline 3D fully solved solver architecture was successfully validated against recent experimental calorimetric data from a standard 18650 cylindrical cell, demonstrating a maximum relative error below 3% and proving grid independ-ence through a systematic mesh sensitivity study. The validated framework was then implemented in COMSOL Multiphysics to compare the fully resolved 3D model with the proposed hybrid approach under constant-current constant-voltage (CCCV) charging and constant-current (CC) discharging at C/2, 1C, and 2C. The hybrid model accurately reproduces the cell's thermal evolution, exhibit-ing relative errors below 0.5% at C/2, approximately 2% at 1C, and around 5% at 2C. Concurrently, the computational demand is drastically reduced from approx-imately 2.3×10¹⁹ to 4.1×10¹⁶ floating-point operations, thereby confirming the effectiveness, accuracy, and scalability of the proposed hybrid framework for efficient multi-physics battery simulations.