【摘要】 利用多物理场耦合软件COMSOL-Multiphisics建立了二维轴对称电化学-热耦合模型。探究了不同倍率放电下18650磷酸铁锂电池电极区域和隔膜区域的产热情况,并根据不同区域的热量积累,进一步分析了放电倍率的增加对反应热、欧姆热以及极化热等不同类型产热的影响。结果表明:随着放电倍率的增加,产热区域主要以正极产热和隔膜产热为主,产热类型主要以欧姆热为主,3 C放电时欧姆热占总产热的72.43%,反应热和极化热相对占比较小。更多还原

【Abstract】 In this paper, a two-dimensional axisymmetric electrochemical-thermal coupling model is established using the multiphysics coupling software COMSOL-Multiphisics. The heat generation in the electrode area and diaphragm area of the 18650 lithium iron phosphate battery under different discharge rates is explored. According to the heat accumulation in different regions, the influence of the increase of the discharge rate on different types of heat generation such as reaction heat, ohmic heat and polarization heat is further analyzed. The results show that with the increase of the discharge rate, the heat generation area is mainly the positive electrode and the diaphragm heat generation, and the heat generation type is mainly ohmic heat. The ohmic heat accounts for 72.43% of the total heat generation during 3 C discharge, and the reaction heat and polarization heat is relatively small.更多还原