A non-iterative method for solving single particle models of lithium-ion battery with electrolyte dynamics

초록

A non-iterative approach for solving the single particle model of lithium-ion batteries with electrolyte dynamics (SPMe) is proposed by strategically designing the solution procedure. First, solid-phase diffusion in the active materials is solved using the tri-diagonal matrix algorithm (TDMA). Next, by utilizing an effective diffusion length under uniform current density, the ion transport in the electrolyte is reduced to solving a 3 & times;3 matrix. Then, with the negative electrode potential set to 0 V, and the negative electrode over-potential and the electrolyte potentials at both electrodes are evaluated analytically. Finally, the positive electrode over-potential and the equilibrium potential are added to the positive electrode electrolyte potential to determine the cell voltage. Through this process, the SPMe is solved non-iteratively while retaining concentration-and temperature-dependent electrolyte transport properties. As a result, a full constant-current discharge is solved in similar to 0.1 ms and a driving profile in 1 to 2 ms, enabling near-instantaneous simulation of battery behavior. Comparisons with the PyBaMM SPMe and the P2D model show that the present method reaches comparable voltage accuracy to the PyBaMM SPMe across various operating conditions. This method enables applications that require rapid, large-scale simulations, such as parameter identification and hardware-in-the-loop simulations.

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