Energy Storage Science and Technology ›› 2020, Vol. 9 ›› Issue (5): 1497-1504.doi: 10.19799/j.cnki.2095-4239.2020.0170

• Energy Storage Materials and Devices • Previous Articles     Next Articles

Impact of number of electrode plate on heat accu mulation effect for lithium ion battery

Wen PENG(), Liuqian YANG, Zhendong ZHU   

  1. Hefei Gotion High-tech Power Energy Co. Ltd. , Hefei 230012, Anhui, China
  • Received:2020-05-08 Revised:2020-05-20 Online:2020-09-05 Published:2020-09-08
  • Contact: Wen PENG E-mail:pengwen@gotion.com.cn

Abstract:

The electrode plates of lithium-ion batteries are the most important parts of the cell. An increase in the number of electrode plate layers can increase the capacity of the battery but also causes heat generation accumulation inside the battery and blocks heat dissipation externally, which ultimately threatens the safety of the battery. In this study, a three-dimensional layered electrochemical-thermal model is proposed for a 10 A·h lithium iron phosphate battery. The influence of the number of electrode plates on the heat accumulation effect is first analyzed theoretically, and then a temperature distribution validation is conducted to ensure the accuracy of the model. Subsequently, the effect of the number of electrode plates on the temperature distribution is investigated. The discharge rate and the number of electrode plate layers are both considered to examine the heat accumulation effect of lithium ion battery. The design basis of the number of electrode plate layers is ultimately provided. The results show that the heat accumulation effect is strengthened with the increase in the number of electrode plate layers, leading to a temperature increase of the battery. In addition, there is a larger temperature gradient in the direction perpendicular to the electrode plate. With the increase in the rate and number of electrode plate layers, the temperature of the tabs becomes higher than that of the cell and the high temperature region gradually concentrates in the tabs; therefore, the dissipation of the tabs is considered. In addition, the temperature deviation also increases as the discharge rate increases; the temperature deviation increases by approximately 11.2 times when the rate increases from 3 C to 10 C. Therefore, if the strategy of fast chargingdischarge is implemented for the battery, the number of electrode plates of the battery should not be too large to avoid an uneven distribution of the internal thermo-electrochemical properties caused by the excessive temperature differences in the battery, which eventually leads to high local temperatures or capacity degradation.

Key words: lithium ion battery, number of electrode plate, heat accumulation effect, electrochemical-thermal model, temperature distribution

CLC Number: