Accelerated Battery Lifetime Simulations Using Adaptive Inter-Cycle Extrapolation Algorithm

We propose algorithms to speed up physics-based battery lifetime simulations by one to two orders of magnitude compared to the state-of-the-art. First, we propose a reformulation of the Single Particle Model with side reactions to remove algebraic equations and hence reduce stiffness, with 3x speed-up in simulation time (intra-cycle reformulation). Second, we introduce an algorithm that makes use of the difference between the fast timescale of battery cycling and the slow timescale of battery degradation by adaptively selecting and simulating representative cycles, skipping other cycles, and hence requires fewer cycle simulations to simulate the entire lifetime (adaptive inter-cycle extrapolation). This algorithm is demonstrated with a specific degradation mechanism but can be applied to various models of aging phenomena. In the particular case study considered, simulations of the entire lifetime are performed in under 5 s. This opens the possibility for much faster and more accurate model development, testing, and comparison with experimental data.

Automated summary

Two algorithms are proposed to significantly accelerate physics-based battery lifetime simulations, including a reformulation of the Single Particle Model and an adaptive cycle selection method. In a specific case study, simulations of the entire battery lifetime are completed in under 5 seconds, allowing for faster and more accurate model development, testing, and comparison with experimental data.