Increasing greenhouse gas (GHG) emissions in the atmosphere and the scarcity of fossil fuel sources have encouraged car manufacturers to develop more environmentally friendly electric vehicles (EVs). The technology advancements of EVs—those with battery systems in particular—have increased their travel distances. Therefore, increasing and maintaining the battery capacity is a key concern in the development of sustainable EVs. In this study, passive cooling systems were constructed with a heat pipe and phase change material (PCM), and their performances were investigated with battery simulators. The aim was to determine the effectiveness of the cooling system and to identify the optimal PCM (beeswax or Rubitherm RT 44 HC) for a temperature range of 25–55 °C. The use of a heat pipe could decrease the battery temperature by 26.62 °C under a 60 W heat load compared to the case without passive cooling system. Furthermore, the addition of RT 44 to a heat pipe resulted in a maximal temperature decrease of 33.42 °C. Thus, an RT 44 HC is more effective than beeswax because its melting temperature lies within the recommended range of the battery working temperature, and its latent heat allows the absorption of more heat compared to beeswax.

大气中温室气体（GHG）排放量的增加以及化石燃料资源的匮乏促使汽车制造商开发出更加环保的电动汽车（EV）。电动汽车的技术进步，尤其是电池系统的技术进步，增加了其行驶距离。因此，增加和维持电池容量是可持续电动汽车发展中的关键问题。在这项研究中，被动冷却系统由热管和相变材料（PCM）构成，其性能通过电池模拟器进行了研究。目的是确定冷却系统的效率，并确定在25–55°C的温度范围内的最佳PCM（蜂蜡或Rubitherm RT 44 HC）。使用热管会使电池温度降低26。与没有被动冷却系统的情况相比，在60 W热负载下为62°C。此外，在热管中添加RT 44导致最大温度降低了33.42°C。因此，RT 44 HC比蜂蜡更有效，因为它的熔化温度在电池工作温度的建议范围内，并且它的潜热比蜂蜡吸收更多的热量。