关键词: 锂离子电池, 热参数辨识, 实验条件, 无量纲, 敏感性分析

Abstract:

Thermal parameter estimation, of fundamental importance for thermal design and management of lithium-ion batteries (LIBs), is challenging as LIBs possess complicated structure with remarkable heterogeneities. The experimental setup to estimate these thermal parameters have many conditions at play, the influence of which on the precision of the estimation methods is yet largely unclear. Employing a non-dimensional thermal model of LIB, we analyze how these experimental conditions, including the radius and applied power of the circular planar heater, the placement of thermocouples, the heating duration, and the thickness of the LIB, dictate the precision of a thermal parameter estimation method we developed recently. Generally, a higher power of the heater leads to higher precision, but there is an upper bound imposed by the safety concerns. we identify the lateral limit for the placement of thermocouples, which is extended when the heater's power is higher. The allowable range of heating duration is reduced at greater ratio of the parallel to perpendicular thermal conductivity. In addition, the thermal parameter estimation method following the non-dimensional approach enjoys a much wider applicability for thermal conductivities of the LIBs with lower thickness-width ratio.

Key words: lithium-ion batteries, thermal parameter estimation, experimental conditions, nondimensionalization, sensitivity analysis