【摘要】 为保证锂电池在低温环境下的高效运行,利用ANSYS软件建立了锂电池相变材料三维热管理模型,用数值模拟的方法研究了基于相变材料的锂电池在低温环境下的保温性能以及静置后在放电过程中温度的变化。研究结果表明:在环境温度为-10℃、锂电池初始温度为25℃的情况下,包裹相变材料的锂电池温度维持在0℃以上的时间与没有任何保温处理的锂电池相比提高了130%,且保温时间随相变材料导热系数的降低而延长;在相同的包裹厚度(10 mm)下,包裹8 mm相变材料外加2 mm保温材料的锂电池的保温时间比只包裹10 mm相变材料的锂电池提高了20%。包裹相变材料的锂电池在-10℃的低温环境下放置一定的时长后仍能在适宜的工作温度下放电,但当放置时间过长导致锂电池的初始温度降至与环境温度一致后,包裹的相变材料反而会阻碍锂电池的启动。更多还原

【Abstract】 In order to ensure the high-efficiency operation of lithium batteries in low temperature environments, a three-dimensional thermal management model of phase change materials for use in lithium battery packs has been established using ANSYS. The numerical simulation method was used to study the performance of phase change materials as thermal insulators for lithium batteries and estimate the temperature changes during the discharge process at low temperature. The results showed that when the ambient temperature was-10 ℃ and the initial temperature of the lithium battery was 25 ℃, the temperature of the lithium battery wrapped with phase change material remained above 0 ℃ for a duration which was 130% longer than that for the lithium battery without any thermal insulation, and the temperature retention time increased as the thermal conductivity of the phase change material decreased. The temperature retention time of a lithium battery wrapped with an 8 mm layer of phase change material and a 2 mm layer thermal insulation material was 20% longer than that for the lithium battery wrapped with a single 10 mm layer of phase change material. Lithium batteries wrapped with phase change materials can still discharge at a suitable working temperature after being placed at an ambient temperature of-10 ℃ for a certain period of time. However, when the time required for the initial temperature of the lithium battery to reach the same temperature as the ambient temperature is too long, the presence of the phase change material wrapping will hinder the startup of the lithium battery.更多还原