基于高浓度相变微胶囊悬浮液的全气候电池热管理实验研究OA

Ensuring the safe and stable operation of lithium-ion batteries in electric vehicles across a wide temperature range of-30℃to 40℃requires highly efficient battery thermal management systems(BTMS)capable of precise temperature regulation.Such systems mitigate capacity degradation at low temperatures and reduce the risk of thermal runaway at high temperatures.Microencapsulated phase change material slurry(MPCMS)has emerged as a promising working fluid for BTMS applications.While prior studies have primarily focused on low-concentration MPCMS,this study investigates a comprehensive all-climate BTMS employing MPCMS at high mass fractions(5%—30%).The thermal management performance of the system was systematically evaluated under three representative operating scenarios:thermal insulation and storage at low temperatures,cold storage and heat absorption at moderate temperatures,and heat dissipation and cooling at high temperatures.Electrically heated rods were used to simulate battery thermal loads.Experimental results indicate that,under low-temperature conditions(-30℃),the inclusion of 5%,15%,and 30%MPCMS,in synergy with an insulation layer,extended thermal preservation time by 12.4%,24.9%,and 34.1%,respectively,compared to a system without MPCMS.At moderate ambient temperature(23℃,below the phase-change point of the microcapsules),MPCMS effectively absorbs heat generated during battery discharge.Under 1 C,2 C,and 3 C discharge rates,the maximum temperature reductions achieved were 2.6℃,4.7℃,and 5.2℃,respectively,relative to the system without MPCMS.Notably,the 15%MPCMS formulation exhibited an optimal balance between latent heat absorption capacity and convective heat transfer performance.Under high-temperature conditions(40℃),even when the heating rod simulated a 3 C discharge thermal load,the system with 30%MPCMS maintained the battery temperature below 40℃by sustaining a 10℃temperature difference between the cooling water inlet and the ambient environment.These findings highlight the significant potential of high-concentration MPCMS as an effective thermal management medium for lithium-ion batteries,enabling reliable thermal regulation across diverse and challenging climatic conditions.