Hopping through the interfaces: a multiscale chemo-mechanic model for energy materials

由能量材料中的电化学过程引起的机械损伤可以显著改变其质量传输能力和能量存储系统的整体性能。损伤通常在材料的内部界面处开始，随后破坏离子和电子传导路径。界面损伤和离子传输之间的耦合尚未完全理解，需要在纳米尺度上描述其起源。该项目将通过开发一种基于贝叶斯推理的新型数据驱动多尺度方法，将第一原理计算与连续建模框架联系起来，能源材料中电化学过程引起的机械损伤可以显著改变其质量（例如锂离子）运输能力和能量存储系统的整体性能。这种损伤通常在材料的内部界面处以微尺度开始，随后破坏离子和电子导电路径，从而降低能量材料的电化学性能。界面损伤和离子输运之间的耦合尚未完全理解，需要在纳米尺度上详细描述其起源。本项目将通过开发一种新的数据驱动的多尺度方法，将第一性原理计算与连续模拟框架联系起来，从而加深对能量材料中各种长度尺度界面的损伤-输运耦合的理解。这将同时能够确定相关的模型参数，说明其可变性，并量化其不确定性。最终的界面模型将在有限元方法中实施，并应用于微观尺度的两个案例研究：（a）活性电极颗粒内的晶间损伤，和（B）活性颗粒与周围材料之间的界面损伤（例如固体电解质），这两个项目都受到电化学循环的影响。该项目还将与实验合作伙伴进行的纳米级实验研究相联系（Piper教授，EIC/WMG）将建模工作与实验相匹配。

Mechanical damage arising from electrochemical processes in energy materials can alter significantly their mass transport capability, and overall performance of energy storage systems. The damage is frequently initiated at material's internal interfaces, subsequently disrupting ionic and electronic conductivity paths. The coupling between interfacial damage and ionic transport is not yet fully understood, and requires description of its origins at the nanoscale. This project will provide enhanced understanding of the damage-transport coupling for various interfaces in energy materials across the length scales by developing a novel data-driven multiscale methodology based on the Bayesian inference, linking first-principles calculations with the continuum modelling framework, and subject to physical constraints.Mechanical damage arising from electrochemical processes in energy materials can alter significantly their mass (e.g. Li-ion) transport capability, and overall performance of energy storage systems. The damage is frequently initiated at material's internal interfaces at the microscale, subsequently disrupting ionic and electronic conductivity paths, and thus reducing electrochemical performance of energy materials. The coupling between interfacial damage and ionic transport is not yet fully understood, and requires detailed description of its origins at the nanoscale.This project will provide enhanced understanding of the damage-transport coupling for various interfaces in energy materials across the length scales by developing a novel data-driven multiscale methodology linking first-principles calculations with the continuum modelling framework. That will simultaneously enable to identify relevant model parameters, account for their variability, and quantify their uncertainty. The ultimate interface model will be implemented within a finite-element approach, and applied to two case studies at the microscale: (a) intergranular damage within active electrode particles, and (b) interface damage between active particles and surrounding material (e.g. solid electrolyte), both subject to electrochemical cycling.The project will also be linked to nanoscale experimental investigations carried out by the experimental partner (Prof Piper, EIC/WMG) to match modelling efforts with experiments.