当前位置: X-MOL 学术Electrochim. Acta › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Thermal-electrochemical parameters of a high energy lithium-ion cylindrical battery
Electrochimica Acta ( IF 6.6 ) Pub Date : 2022-06-12 , DOI: 10.1016/j.electacta.2022.140700
Kieran O'Regan, Ferran Brosa Planella, W. Dhammika Widanage, Emma Kendrick

To accurately predict the lifetime of commercial cells, multi-physics models can be used, however the accuracy of the model is heavily reliant upon the quality of the input thermodynamics and kinetic parameters. The thermal properties and the variability of the transport and thermodynamic properties with temperature and state-of-charge (SoC) in a high energy 21700 cylindrical cell were measured. The parameters are used in a DFN and 0D thermal model, and the model was tested against experimental data from the commercial cell. The results demonstrate an improved model fit by 27% when including the parameter dependency upon SoC and temperature, compared to without. The maximum power is limited by the negative electrode, which has lower diffusion coefficients and current exchange density over the full SOC window compared to the positive electrode, particularly at 50% and 80% SoC (x=0.45 and 0.85), reflected in high activation energies of up to 60 kJK−1 and low diffusion coefficients of 5 × 10−13 cm−2s−1 at 25°C. At 45°C, the reaction rate increases to greater than that of the positive, diffusion also increases, 2 × 10−12 cm−2s−1, but is still limiting. This work provides for the first time an electrochemical and thermal experimental dataset for a high energy cell, and provides insights into the rate limitations and prediction errors.



中文翻译:

高能锂离子圆柱电池的热电化学参数

为了准确预测商业电池的寿命,可以使用多物理模型,但是模型的准确性在很大程度上取决于输入热力学和动力学参数的质量。测量了高能 21700 圆柱形电池中的热特性以及传输和热力学特性随温度和充电状态 (SoC) 的变化。这些参数用于 DFN 和 0D 热模型,并根据商业电池的实验数据对该模型进行了测试。结果表明,与不包含对 SoC 和温度的参数依赖性时,模型拟合度提高了 27%。最大功率受到负极的限制,与正极相比,负极在整个 SOC 窗口内具有较低的扩散系数和电流交换密度,-1和25°C时 5 × 10 -13 cm -2 s -1的低扩散系数。在 45°C 时,反应速率增加到大于正极的反应速率,扩散也增加,2 × 10 -12 cm -2 s -1,但仍然有限。这项工作首次为高能电池提供了电化学和热实验数据集,并提供了对速率限制和预测误差的见解。

更新日期:2022-06-13
down
wechat
bug