摘要
Abstract
Traditional battery thermal management structure that integrates a phase change material(PCM)with air cooling—using"X"-shaped fins and copper columns—can significantly improve the heat dissipation efficiency of air cooling and meet the temperature requirements of batteries under harsh conditions.However,these structures still exhibit notable deficiencies in heat dissipation efficiency.To address these issues,we propose a novel and innovative"dissipation-storage-integrated"thermal management structure that effectively combines PCM and air cooling.This study investigates the thermal characteristics of the proposed structure during repeated charge-discharge cycles,in which the batteries discharge at a relatively high rate of 6 C and charge at 2 C under challenging high-temperature conditions.The effects of the PCM physical parameters(e.g.,melting point,thermal conductivity,and specific heat capacity)and different cold-plate structural parameters(e.g.,thickness,shape,and fin density)are analyzed to evaluate their influence on the heat transfer characteristics of the structure.The results demonstrate that the proposed battery thermal management structure is highly effective.It can successfully maintain the maximum temperature of a single battery cell within a safe range of 45℃and limit the maximum temperature difference to within 3℃throughout multiple charge-discharge cycles.Among PCM parameters,the melting point strongly influences the battery temperature rise.An excessively high melting point inevitably leads to an overly high maximum battery temperature,jeopardizing the battery's performance and lifespan.In contrast,an excessively low melting point causes PCM to melt alarmingly fast.As a result,the PCM-based cold-plate lacks the essential temperature-regulating capacity in the later part of the cycle,significantly accelerating the battery temperature rise.Provided that PCM does not completely melt,lowering the melting points is more favorable for maintaining safe operating temperatures.Additionally,increasing the thickness of the PCM cold-plate,cold-plate panel,and the fin ribs can significantly enhance the heat dissipation performance and temperature-control stability of the structure,further improving the overall efficiency of the thermal management system.These findings provide valuable methodological support for designing battery thermal management systems that ensure the safety of lithium-ion batteries under long-distance continuous high-speed driving conditions and in cold regions.The proposed approach not only strengthens the theoretical foundation of battery thermal management but also provides practical and valuable guidance for improving the performance and safety of battery systems in demanding application scenarios.关键词
电池热管理/相变材料/风冷/循环充放电Key words
battery thermal management/phase change material/air cooling/charge-discharge cycle分类
信息技术与安全科学
