SGER: Exploratory Research -- A Novel AC Impedance Model for Understanding Transport and Kinetic Limitations of Electrochemical Devices

摘要：Venkat Subramanian机构：田纳西理工大学提案号：0609914（SGER）探索性研究一种理解电化学装置传输和动力学限制的新型交流阻抗模型改进电化学装置（电池、燃料电池、超级电容器、传感器）的设计、经济性和工作范围目前是一个高度优先的领域，因为它们有望在未来的汽车、电力存储、军事、移动站和空间应用中发挥重要作用。锂离子电池（以及类似的其他电池）会随着循环而失去容量。各种传输和反应的限制限制了锂离子电池和其他电化学装置的成本效益和利用。交流阻抗是各种研究人员用来了解电化学系统的一种技术。从交流阻抗数据中理解和提取有用的信息可能是一项复杂的任务。研究人员通常使用基于电路的模型来获得电化学系统的有效电阻和电容。使用电路方法的主要缺点是它只给出感兴趣的系统的集总参数，而不涉及所有有意义的定量系统参数（扩散系数，速率常数等）。用于模拟交流阻抗响应的严格的基于物理的模型涉及求解多个域的多个偏微分方程（PDEs），由于数值和计算的限制，这些模型难以实现。虽然锂离子电池的建模涉及多个领域的多个pde，但本探索性研究计划探索了为两个pde开发PIs新方案以解决此类系统的可能性。该研究建立在pi过去在电化学系统数学建模和计算方法领域的成果之上，是一项综合努力，旨在开发下一代高效新颖的封闭形式解决方案，以更好地利用交流阻抗技术理解电化学器件。知识优势- PIs的数字符号解（NSS）在空间坐标上是数字的，在所有系统参数上是封闭的。所提出的方案将有助于弥合纯数值解和严格解析解之间的差距。如果探索性研究取得成功，那么数学解方案可以扩展到控制各种器件电化学行为的多个域的多个偏微分方程。这些方案可以帮助预测运输和动力学参数，并了解锂离子电池的局限性，锂离子电池在汽车、电力存储等领域的应用对环境有潜在的好处。

ABSTRACTPI: Venkat Subramanian Institution: Tennessee Technological UniversityProposal Number: 0609914Title: (SGER) Exploratory Research A Novel AC Impedance Model for Understanding Transport and Kinetic Limitations of Electrochemical DevicesImproving the design, economy and operating range of electrochemical devices (batteries, fuel cells, super capacitors, sensors) is presently a high priority area as they are expected to play a vital role in the future for automobiles, power storage, military, mobile-station and space applications. Lithium-ion batteries (and similarly other batteries) lose their capacity with cycles. Various transport and reaction limitations restrict the cost effectiveness and utilization of Li-ion batteries and other electrochemical devices. AC impedance is a technique used by various researchers to understand electrochemical systems.Understanding and extracting useful information from AC impedance data can be a complex task. Typically circuit based models have been used by researchers to obtain effective resistance and capacitance of electrochemical systems. The main drawback with using the circuit approach is that it only gives lumped-parameters for the system of interest and does not involve all the meaningful quantitative system parameters (diffusion coefficient, rate constants, etc.). Rigorous physics based models for simulating AC impedance response involves solving multiple partial differential equations (PDEs) in multiple domains making the models prohibitive because of numerical and computation constraints. Though modeling Lithium-ion batteries involve multiple PDEs in multiple domains, this exploratory research proposal explores the possibility of developing PIs novel scheme for two PDEs to solve such systems. The research builds on the PIs past results in the area of mathematical modeling and computational methods for electrochemical systems and is an integrated effort to develop the next generation of high-efficient novel closed-form solutions to better understand electrochemical devices using AC impedance technique.Intellectual Merit - The PIs Numeric Symbolic Solution (NSS) is numerical in the spatial coordinate and closed-form in all the system parameters. The proposed schemes will help bridge the gap between a purely numerical solution and a rigorous analytical solution. Broader Impacts If the exploratory research is successful, then the mathematical solution scheme can be extended to multiple partial differential equations in multiple domains that govern the electrochemical behavior of various devices. These schemes could help predict transport and kinetic parameters and understand the limitations of Lithium-ion batteries, whose use in automobiles, power storage, etc. applications have potential benefits for the environment.