Experimental and simulation study on thermal characteristics of 18,650 lithium–iron–phosphate battery with and without spot–welding tabs

• Published in: Applied thermal engineering 2020-02, Vol.166, p.114648, Article 114648
• Main Authors: Liu, Shuaihua, Liu, Xunliang, Dou, Ruifeng, Zhou, Wenning, Wen, Zhi, Liu, Lin
• Format: Article
• Language: English
• Subjects: Ambient temperature; Batteries; Computer simulation; Discharge; Heat generation; Iron; Lithium; Lithium-ion battery; Nickel; Nickel strip; Product safety; Strip; Temperature rise; Thermal energy; Welded structures; Welding
• ISSN: 1359-4311; 1873-5606
• DOI: 10.1016/j.applthermaleng.2019.114648

•The effects of spot-welded nickel strip on battery performance are studied experimentally.•The effects of ambient temperature on internal heat generation of 18,650 LPF is analyzed.•A two-dimensional electrochemical–thermal coupled model of 18,650 LPF is established. Thermal condition is crucial to the safety and performance of battery and battery pack. In this work, a two–dimensional, axisymmetric, electrochemical–thermal coupled model of 18,650 lithium–iron–phosphate battery is established and validated by our own experimental results. The model is used to investigate the effect of ambient temperature on battery performance and heat generation. The results show that the temperature rise in the battery increases with decreasing ambient temperature, which is mainly due to the increase in heat generated from Ohmic loss and polarization with decreased ambient temperature. While considering the welded structure, in which the cylindrical batteries are assembled into a battery pack, the effect of spot–welded nickel strip on battery performance under different discharge rates is experimentally studied at the ambient temperature of 298.15 K. It is found that the battery with the spot-welded nickel strip has a lower discharge plateau and a higher heat generation rate. The nickel strip has a greater impact on battery performance and temperature if the discharge C-rate increases.