Abstract Accurate and rapid prediction of temperature distribution in a large Li-ion battery pack comprising thousands of cells is critical for ensuring safety and performance of battery packs for electric vehicles. Due to the multiscale geometry and the large number of individual cells in an automotive battery pack, full-scale thermal simulations typically take a long time to complete. Approaches for rapidly computing the temperature field in a large battery pack without significant loss of accuracy is, therefore, a key technological need. This paper presents thermal simulations of a large, air-cooled Li-ion battery pack containing thousands of individual cells using the submodeling technique. A coarse model that neglects fine geometrical details is first solved, and the results are used to solve a more detailed sub-model. It is shown that this approach results in 7X reduction in computation time while preserving the accuracy of the predicted temperature field. Trade-offs between computation time and accuracy are examined. The submodeling technique is used to investigate the thermal design of a large Li-ion battery pack, including the effect of discharge rate and coolant flowrate on temperature field, and the thermal response to a pulsed spike in discharge rate. Limitations of the submodeling technique are discussed. The technique discussed here is a general one, and may help significantly reduce computation time for thermal design and optimization of large, realistic Li-ion battery packs.

中文翻译：

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使用子建模技术对大型锂离子电池组进行高效计算的热模拟

摘要 准确快速地预测由数千个电池组成的大型锂离子电池组的温度分布对于确保电动汽车电池组的安全性和性能至关重要。由于汽车电池组中的多尺度几何形状和大量单个电池，全尺寸热模拟通常需要很长时间才能完成。因此，在不显着降低精度的情况下快速计算大型电池组中的温度场的方法是一项关键的技术需求。本文介绍了使用子建模技术对包含数千个单体电池的大型风冷锂离子电池组进行的热模拟。首先求解忽略精细几何细节的粗略模型，然后将结果用于求解更详细的子模型。结果表明，这种方法使计算时间减少了 7 倍，同时保持了预测温度场的准确性。检查计算时间和准确性之间的权衡。子建模技术用于研究大型锂离子电池组的热设计，包括放电速率和冷却剂流量对温度场的影响，以及对放电速率脉冲尖峰的热响应。讨论了子建模技术的局限性。这里讨论的技术是一种通用技术，可能有助于显着减少大型、逼真的锂离子电池组的热设计和优化的计算时间。子建模技术用于研究大型锂离子电池组的热设计，包括放电速率和冷却剂流量对温度场的影响，以及对放电速率脉冲尖峰的热响应。讨论了子建模技术的局限性。这里讨论的技术是一种通用技术，可能有助于显着减少大型、逼真的锂离子电池组的热设计和优化的计算时间。子建模技术用于研究大型锂离子电池组的热设计，包括放电速率和冷却剂流量对温度场的影响，以及对放电速率脉冲尖峰的热响应。讨论了子建模技术的局限性。这里讨论的技术是一种通用技术，可能有助于显着减少大型、逼真的锂离子电池组的热设计和优化的计算时间。