(北京有色金屬研究總院 動力電池研究中心，北京 100088)
摘 要: 為了明確圓柱形C/LiFePO4動力蓄電池放電過程中的溫度特性及其產(chǎn)熱機理，利用自動充放電儀對其在不同倍率放電過程中表面溫度的變化進行研究，并對該電池在放電過程中的產(chǎn)熱率進行計算。結(jié)果表明：相同放電時間的表面溫度增加與放電電流呈拋物線關(guān)系，放電結(jié)束時表面溫度增加則與放電電流呈線性關(guān)系；電池內(nèi)部的熱效應(yīng)主要為不可逆阻抗熱和電池反應(yīng)的可逆熱效應(yīng)，0.3C、1C、2C和3C放電時，不可逆阻抗熱的平均產(chǎn)熱率分別是總平均產(chǎn)熱率的85.0%、98.0%、99.4%和99.6%，電池反應(yīng)的可逆熱效應(yīng)所占比例很小；小電流放電時，電池表面溫度的下降與電池反應(yīng)的可逆熱效應(yīng)有關(guān)。
關(guān)鍵字: LiFePO4；鋰離子動力電池；溫度特性；熱行為
（Research and Development Center for Vehicle Battery and Energy Storage,
General Research Institute for Nonferrous Materials, Beijing 100088, China）
Abstract:In order to investigate the temperature characterize and heat generation mechanism of a cylindrical power secondary battery using graphite and LiFePO4 as anode and cathode, its surface temperature change at different discharge rates were studied by a automatic charge and discharge device. Moreover, its heat generation rate during discharge was calculated. The results show that, at the same discharge time, the relationship between the surface temperature rising and the discharge current is parabolic, whereas at the end of discharge, the surface temperature rising is a liner relationship with the discharge current. The irreversible resistive heating and reversible entropic heat are the major heat generation sources inside the battery. The average rates of the irreversible resistive heating at 0.3C, 1C, 2C and 3C rate are about 85.0%, 98.0%, 99.4% and 99.6% of that of the total heat generation, respectively. The proportion of reversible entropic heat is very small. At low discharge current, the surface temperature drop is dominated by reversible entropic heat.
Key words: LiFePO4; Li-ion power battery; temperature characterize; thermal behavior
