The performance of lithium batteries relies significantly on the ambient temperature. They often become ineffective or demonstrate a shortened lifespan at low temperatures. Therefore, designing an effective, uniform, and energy-efficient heating system for the battery pack becomes the key to the development of electric vehicles in northern environment. The method of numerical simulation adopted from computational fluid dynamics (CFD) was introduced, and the porous theory was used to conduct a simplified analysis of battery module in the battery pack. The rise of temperature during the heating process of the battery pack of electric vehicles was simulated, and the simulation and experimental results were compared. Results showed that the combination of simulation method and porous simplification model was effective in evaluating the heating system of electric vehicle battery pack. The heating strategy was modified based on the analysis results, and a heating system that consisted of multiple heating zones was designed, which can keep the heating power of each part in control. Results showed that there was an overall power reduction of 167 W (about 7%) under the optimized multi-zone heating system, and the battery pack can still be heated from ?13 °C to 5 °C within 50 minutes, with the maximum temperature difference within the zones of the battery pack being kept under 5 °C.%锂离子电池对温度环境要求严苛，在低温下常出现失效、寿命衰退等现象. 因此，为电池包设计高效、均匀且节能的加热方案，成为电动汽车在北方环境下发展的关键. 引入计算流体动力学（CFD）的仿真计算方法，并采用多孔介质理论对电池包中电池模块进行简化分析，对电动汽车电池包在加热过程中的温升特性进行仿真分析计算，将仿真计算结果与实测数据进行对比验证，证明所采用的仿真方法及多孔介质简化模型可有效应用于电动汽车电池包的加热方案评估. 根据分析结果对加热方案提出修正，并设计分块化的加热方案，即对局部加热功率进行控制. 计算结果显示，优化后的分块加热方案，在总体功率降低167 W（约7%）的情况下，仍然可在50 min内将电池包从?13 °C加热到5 °C，并且将电池包中电池区域最大温差控制在5 °C以内.
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