Battery design toward fast charging technology: a parametric survey

Battery design has important effects on its fast-charging performance. This research took a prismatic NMC lithium-ion cell as the object, and built its finite element model based on the electrochemical and thermal theories. The voltages during the 1C, 3C, and 6C charging processes were obtained and compared with the experiment results, which verified the effectiveness of the model. By changing the structure parameters and material parameters of the cell, their influence on the fast-charging capability of the cell was systematically investigated. The structure parameters included the active layer thickness, cell balance, and separator thickness. The material parameters included the particle radii in the positive electrode and negative electrode, the porosities of the positive active layer, negative active layer, and separator. It was found that most of them would influence the fast-charging capability of the cell distinctly, except for the cell balance. Compared with others, the porosities of the positive active layer, negative active layer, and separator had the most significant influence on the fast-charging capability of the cell. And the smaller the porosities were, the greater the influence was. The conclusions obtained could provide references for the structure design and material design of lithium-ion batteries toward fast-charging technology.