A Lithium-Ion Battery Simulator Based on a Diffusion and Switching Overpotential Hybrid Model for Dynamic Discharging Behavior and Runtime Predictions

Abstract

Abstract:A new battery simulator based on a hybrid model is proposed in this paper for dynamic discharging behavior and runtime predictions in existing electronic simulation environments, e.g., PSIM, so it can help power circuit designers to develop and optimize their battery-powered electronic systems. The hybrid battery model combines a diffusion model and a switching overpotential model, which automatically switches overpotential resistance mode or overpotential voltage mode to accurately describe the voltage difference between battery electro-motive force (EMF) and terminal voltage. Therefore, this simulator can simply run in an electronic simulation software with less computational efforts and estimate battery performances by further considering nonlinear capacity effects. A linear extrapolation technique is adopted for extracting model parameters from constant current discharging tests, so the EMF hysteresis problem is avoided. For model validation, experiments and simulations in MATLAB and PSIM environments are conducted with six different profiles, including constant loads, an interrupted load, increasing and decreasing loads and a varying load. The results confirm the usefulness and accuracy of the proposed simulator. The behavior and runtime prediction errors can be as low as 3.1% and 1.2%, respectively.

Design and Implement of a Battery Simulator

“…The communication port of battery simulator consists of RS485 interface and optical coupling isolation circuit [4][5]. The circuit of communication port is shown in In practical application of complex, there will be a high common-mode voltage between each node of RS485 due to the different reference.…”

Comparative Analysis of Battery Behavior with Different Modes of Discharge for Optimal Capacity Sizing and BMS Operation

“…When the battery has low load or no load for some time, active charges have enough time to diffuse to the electrodes, and charge recovery takes place. Thus the usable capacity of the battery discharged at high rate is lower than that of one discharged at low rate [15]. of the most aged cell and it's on-time replacement in the case of battery packs with multiple cells can boost the number of cycles before the battery reaches it's end of life as suggested by [14].…”

“…When the battery has low load or no load for some time, active charges have enough time to diffuse to the electrodes, and charge recovery takes place. Thus the usable capacity of the battery discharged at high rate is lower than that of one discharged at low rate [15]. …”