Abstract: Lithium-ion batteries continuously generate heat during work, So, when used as electric vehicle power supply, the battery pack may be quite hot and the temperature differences among monomers may be very large without effective thermal management measures, which will deteriorate its performance and lifespan. Generally uses various techniques such as forced air cooling, liquid circulation cooling, phase change material cooling and heat pipe cooling, have been applied in Battery thermal management system(BTMs) but with the shortcomings of complicated structure and high cost. In this work, pure copper fins were proposed for BTMs and experimental research was conducted. By changing the discharge rate and thickness of fins, the thermal characteristics of the battery pack under different working conditions is studied. The results showed that under the condition of natural convection, adding fin could significantly keep the temperature of battery pack from overheating, and improve the temperature distribution inside the battery pack. Thicker fins can meet the temperature requirements of higher discharge rate and greater discharge depth.

Key words: lithium battery, thermal management, fin, convection, heat transfer, safety

摘要： 锂电池在使用时会持续产热,作为电动汽车电源使用时若不采取有效的热管理措施,可能导致其温度过高、电池单体间温差过大,从而影响其性能和寿命.目前电池热管理系统多采用强制风冷、循环液冷、相变冷却、热管冷却等方法,结构复杂且成本较高.本文采用纯铜翅片式电池热管理系统并进行了实验研究,通过改变放电倍率和翅片厚度,研究了电池组在不同工况下的热特性.结果表明:自然对流条件下,加装翅片可显著抑制电池组温度过高,并可改善电池组温度分布的均匀性;增加翅片厚度可满足高放电倍率和深度放电时的温度要求.

关键词: 锂电池, 热管理, 翅片, 对流, 传热, 安全