(1. 貴州輕工職業(yè)技術(shù)學(xué)院 先進(jìn)電池與材料工程研究中心，貴陽(yáng) 550025；
2. 安徽利維能動(dòng)力電池有限公司，滁州 239000；
3. 貴州省普通高等學(xué)校石墨烯材料工程研究中心，貴陽(yáng) 550025；
4. 廢舊動(dòng)力電池梯次利用及資源化省級(jí)協(xié)同創(chuàng)新中心，貴陽(yáng) 550025)
摘 要: 本文以磷酸鐵鋰/石墨體系26700圓柱鋰離子電池為研究對(duì)象，通過(guò)使用偽二維電化學(xué)熱模型進(jìn)行建模，分別模擬0.5C以及1C兩種不同倍率的充電策略。結(jié)果表明：模型輸出結(jié)果與電池測(cè)試結(jié)果基本吻合，且在0.5C和1C恒流充電條件下，電池絕熱溫升實(shí)測(cè)數(shù)據(jù)與模型模擬結(jié)果基本一致。在1C充電過(guò)程中，負(fù)極因極化產(chǎn)生的不可逆熱為主要熱源，隨著充電電流增加，負(fù)極過(guò)電位同步增加；而正極因鋰脫嵌產(chǎn)生熵變，反應(yīng)為吸熱過(guò)程，在充電2500~3000 s期間，吸熱熱功率與放熱熱功率持平，電池溫度曲線(xiàn)呈現(xiàn)平臺(tái)形態(tài)。
關(guān)鍵字: 鋰離子電池；偽二維電化學(xué)熱模型；充電溫升
（1. Advanced Batteries and Materials Engineering Research Center, Guizhou Light Industry Technical College, Guiyang 550025, China;
2. EVPS Anhui Power Battery Co., Ltd., Chuzhou 239000, China;
3. Graphene Materials Engineering Research Center of Guizhou Colleges and Universities, Guiyang 550025, China;
4. Provincial Collaborative Innovation Center of Used Power Batteries Recycling, Guiyang 550025, China）
Abstract:In this paper, the electrochemical and thermal behaviors of the LiFePO4/graphite system 26700 cylindrical lithium ion battery were investigated based on pseudo-two-dimensional electrochemical-thermal coupling model. By using this model, the charging processes of LiFePO4/graphite system under two charging strategies with different rates of 0.5C and 1C were simulated, respectively. The results show that the model output results are basically consistent with the battery cell test results. At the same time, under 0.5C and 1C constant current charging conditions, the measured data of the adiabatic temperature rise of the cell is basically consistent with the model simulation results. During the 1C charging process, the irreversible heat generated by the polarization of the negative electrode is the main heat source. As the charging current increases, the negative electrode overpotential increases simultaneously, while the positive electrode changes due to the entropy of lithium deintercalation, and the reaction is an endothermic reaction. In the charging period of 2500-3000 s, the endothermic heat power is the same as the exothermic heat power, and the cell temperature curve appears to be a platform shape.
Key words: lithium ion battery; pseudo-two-dimensional electrochemical-thermal coupling model; charging temperature rise
