Multi-Scale Investigation of Thermodiffusion With Implications To Electrochemical Systems

热扩散的多尺度研究及其对电化学系统的影响

• 批准号: RGPIN-2015-04737
• 负责人: Srinivasan, Seshasai
• 金额: $ 1.6万
• 依托单位: McMaster University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=708552
• 关键词: Multi; Scale; Investigation; Thermodiffusion; Implications

Consistent with McMaster University's and NSERC's missions to foster the discovery and application of knowledge, the aim of this research is to investigate the subject of `Thermodiffusion' at the fundamental as well as applied level. Thermodiffusion, or the Soret-effect, is a coupled mass and heat transfer phenomenon in which the components of a mixture tend to segregate into preferred thermal zones when the domain containing the mixture is subjected to a thermal gradient. It is the underlying principle in many scientific applications and natural processes, namely, field flow fractionation devices, isotope separation, biological and biomolecular processes, stratification of crude oil components in underground reservoirs and freezing processes of foods. Apart from these, recent studies by other researchers also suggest that the Soret-effect in electrochemical systems can play a role in the overall performance of a battery. However, at present there is very little known about this because of (i) the lack of appropriate formulations for the Soret-effect in electrochemical systems as well as (ii) our incomplete understanding of the ageing process of a battery. While the wide spectrum of applications/relevance of thermodiffusion has spurred significant research activity, a comprehensive and satisfactory theoretical explanation of this phenomenon, applicable for every type of fluid mixture is still lacking. This is due to the fact that the response of the constituents in a fluid mixture to a temperature gradient involves a multitude of phenomena at the molecular level that is not completely understood. Keeping these shortcomings in mind, we propose to study thermodiffusion in a multi-scale formalism incorporating the principles of molecular dynamics. This will enable us to account for the effects of the molecular mechanisms on the macroscale transport process, thereby aiding in developing an accurate and comprehensive thermodiffusion model. This multi-scale model will subsequently be applied to study the effects of thermodiffusion on the performance of a Lithium-ion (Li-ion) battery, where much less is known about the impact of mechanisms occurring at the nanoscale on the overall large scale parameters characterizing the battery performance and degradation. While the comprehensive thermodiffusion model to be developed in this research will enable us to improve the current separation technologies in the nuclear and biological industry, the application of the model to study the degradation mechanisms in a battery will enable us to design superior performing batteries. Such high performance batteries will play a vital role in future automobiles, power storage, military, mobile-station, and space applications.

与麦克马斯特大学和 NSERC 促进知识发现和应用的使命相一致，本研究的目的是在基础和应用层面上研究“热扩散”这一主题。热扩散或索雷效应是一种耦合的质量和传热现象，其中当包含混合物的区域受到热梯度时，混合物的组分倾向于分离到优选的热区域中。它是许多科学应用和自然过程的基本原理，即场流分馏装置、同位素分离、生物和生物分子过程、地下储层中原油成分的分层和食品的冷冻过程。除此之外，其他研究人员最近的研究也表明电化学系统中的索雷效应可以在电池的整体性能中发挥作用。然而，目前对此知之甚少，因为（i）缺乏电化学系统中索雷效应的适当公式以及（ii）我们对电池老化过程的不完全了解。虽然热扩散的广泛应用/相关性激发了重要的研究活动，但仍然缺乏适用于每种类型的流体混合物的对这种现象的全面且令人满意的理论解释。这是因为流体混合物中的成分对温度梯度的响应涉及分子水平上的多种现象，而这些现象尚未完全理解。考虑到这些缺点，我们建议结合分子动力学原理在多尺度形式主义中研究热扩散。这将使我们能够解释分子机制对宏观传输过程的影响，从而有助于开发准确且全面的热扩散模型。这种多尺度模型随后将用于研究热扩散对锂离子电池性能的影响，而对于纳米尺度发生的机制对整体大尺度参数的影响知之甚少。表征电池性能和退化。虽然本研究中开发的综合热扩散模型将使我们能够改进核工业和生物工业中当前的分离技术，但应用该模型来研究电池的退化机制将使我们能够设计出性能优越的电池。这种高性能电池将在未来的汽车、储能、军事、移动站和空间应用中发挥至关重要的作用。