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

能量材料在电化学过程中产生的机械损伤会显著改变其传质能力和储能系统的整体性能。损伤通常在材料的内部界面开始，随后扰乱离子和电子传导路径。界面损伤和离子传输之间的耦合尚不完全清楚，需要在纳米尺度上描述其起源。该项目将通过开发一种新的基于贝叶斯推理的数据驱动的多尺度方法，将第一性原理计算与连续介质建模框架联系起来，并受物理约束，从而加深对能源材料中各种界面在长度尺度上的损伤-传输耦合的理解。能源材料中的电化学过程产生的机械损伤可以显著改变其质量(例如锂离子)传输能力和储能系统的整体性能。这种损伤常常发生在材料内部的微尺度界面上，随后扰乱了离子和电子的传导路径，从而降低了能量材料的电化学性能。界面损伤和离子输运之间的耦合还没有完全了解，需要在纳米尺度上详细描述它的起源。这个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统模拟框架联系起来，增强对能量材料中不同界面在长度尺度上的损伤-传输耦合的理解。这将同时能够确定相关的模型参数，解释它们的可变性，并量化它们的不确定性。最终的界面模型将在有限元方法中实现，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，以及(B)活性颗粒与周围材料(例如固体电解液)之间的界面损伤，两者都受到电化学循环的影响。该项目还将与实验合作伙伴(EIC/WMG派珀教授)进行的纳米级实验调查联系起来，以使模拟工作与实验相匹配。

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.