The entropic coefficient of a lithium-ion battery cell is used to calculate the reversible heat of a battery during operation, which is a nonnegligible part of the battery thermal modeling. The contribution of this article is to propose a novel method to establish the entropic coefficient profile of a 26-Ah commercial pouch cell and compare the results with those obtained from the traditional potentiometric and calorimetric methods, and all are found to be in a good agreement. The originality of this article is to use a method, which consists of supplying a square pulse current waveform at a certain frequency, and thus, the resulting heat variation could be successfully linked to the input current using Fourier analysis. The current magnitudes used were 1 and 1.5 C, which are representative of the normal operation current in an electrified vehicle application. The method proposed is found to be cost efficient with a short experiment time and simple experiment setup. In fact, it can be used to characterize cells that are already mounted in a pack without access to a climate chamber or calorimeter.

中文翻译：

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一种确定大型商用电池的熵系数的时间和成本效益方法

锂离子电池的熵系数用于计算电池在运行过程中的可逆热，这是电池热建模中不可忽略的部分。本文的贡献是提出了一种建立 26-Ah 商用软包电池熵系数分布的新方法，并将结果与​​传统电位和量热方法获得的结果进行比较，发现所有结果都具有良好的一致性. 本文的独创性是使用一种方法，该方法包括提供特定频率的方波脉冲电流波形，因此，可以使用傅立叶分析将由此产生的热量变化成功地与输入电流相关联。使用的电流大小为 1 和 1.5 C，它们代表了电动汽车应用中的正常工作电流。发现所提出的方法具有成本效益，实验时间短，实验设置简单。事实上，它可用于表征已安装在电池组中而无需使用气候室或热量计的电池。