CAREER: Electro-Chemo-Mechanics of Multiscale Active Materials for Next-Generation Energy Storage

这项教师早期职业发展（Career）资助将支持综合研究、教育和推广工作，以推进储能材料力学领域的发展。在现代社会，从便携式电子产品到电动汽车，可充电电池在能源存储领域占据主导地位。然而，目前基于微粒的电池技术不足以实现高效、负担得起和安全的能量存储。纳米技术的进步激发了人们将纳米粒子用作电池电极的兴趣。然而，在电池工业将纳米粒子应用于微粒子之前，还有一些与纳米粒子相关的问题需要克服。一条前进的道路在于利用多尺度活性材料来平衡两个世界的优势（微和纳米）。本研究的目标是获得多尺度活性材料相互关联的电学、化学和力学行为的基本知识。这些材料将微尺度粒子与内置的纳米尺度特征结合在一起。该项目将开发一个集成的原子模拟和机器学习框架，以发现下一代储能的最佳多尺度活性材料，这是推进美国经济、繁荣、福利和国防所迫切需要的。综合推广和教育活动将与路易斯·斯托克斯少数民族参与联盟项目合作，为代表性不足的社区大学生提供研究机会。为小学教师培训的工作坊将提供STEM内容，向低年级学生推广科学。此外，与这项研究相关的免费在线研讨会将使全球力学研究界受益。基于纳米材料的电池电极具有以下优点：高倍率、功率密度、重量容量、优异的断裂韧性和抗疲劳性。然而，业界一直抵制用纳米结构的对应物取代微结构电极。纳米材料电池具有体积容量小、库仑效率低、成本高等缺点。解决这一问题的变革性解决方案在于多尺度活性材料。这些材料既可以是工程材料（将纳米颗粒组装成微粒），也可以是天然材料（微米级材料，自然赋予纳米级隧道）。然而，各种计算和实验方面的挑战阻碍了这一领域的研究进展。本项目旨在通过以下四个综合目标克服这些挑战：(i)研究工程多尺度材料中的界面力学，（ii）确定电极/电解质稳定性和固体电解质界面形成，（iii）研究充电/放电循环期间电极内的应力、断裂和电压变化，以及（iv）利用前三个目标的数据来训练最近开发的改进高维神经网络，用于新型多尺度材料的探索。为了精确的电荷计算和正确的力应力分析，将实施非局部远程电荷转移。任务将与同事进行实验验证。该项目将产生基础知识，以推进能源储存材料的力学领域。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This Faculty Early Career Development (CAREER) grant will support integrated research, education, and outreach efforts to advance the field of mechanics for energy storage materials. In modern society, rechargeable batteries dominate the energy storage landscape, from portable electronics to electric vehicles. However, current microparticle-based battery technologies are insufficient for efficient, affordable, and safe energy storage. Advances in nanotechnology have spurred interest in deploying nanoparticles as battery electrodes. However, there are problems associated with nanoparticles that need to be overcome before the battery industry would use them over microparticles. A way forward lies in utilizing multiscale active materials to leverage the advantages of both worlds (micro and nano). The goal of this research is to gain fundamental knowledge of the interrelated electrical, chemical, and mechanical behaviors of multiscale active materials. These materials incorporate microscale particles with built-in nanoscale features. This project will develop an integrated atomistic simulation and machine learning framework to discover the optimal multiscale active materials for next-generation energy storage, which is urgently needed to advance the US economy, prosperity, welfare, and defense. The integrated outreach and educational activities will provide research opportunities for underrepresented community college students in partnership with the Louis Stokes Alliances for Minority Participation program. Workshops for elementary teacher trainees will provide STEM content to promote science among lower-grade students. Additionally, free online workshops related to this research will benefit the worldwide mechanics research community. Nanomaterials-based battery electrodes offer several advantages: high rate, power density, gravimetric capacity, superior fracture toughness, and fatigue resistance. However, the industry has been resistant to replace microstructured electrodes with nanostructured counterparts. Nanomaterials-based batteries have low volumetric capacity, reduced coulombic efficiency, and high cost. The transformative solution to address this issue lies in multiscale active materials. These materials can be either engineered (assembly of nanoparticles into microparticles) or natural (micrometer-scale materials naturally endowed with nanoscale tunnels). However, various computational and experimental challenges have impeded research progress in this area. This project aims to overcome these challenges through four integrated objectives: (i) studying the interfacial mechanics in engineered multiscale materials, (ii) determining electrode/electrolyte stability and solid electrolyte interface formation, (iii) investigating stress, fracture, and voltage variation within electrodes during charge/discharge cycles, and (iv) utilizing data from the first three objectives to train recently developed Modified High Dimensional Neural Networks for novel multiscale materials exploration. The Non-Local Long-Range Charge Transfer will be implemented for accurate charge calculation and correct force and stress analysis. Tasks will be experimentally validated with colleagues. The project will generate fundamental knowledge to advance the field of mechanics of energy storage materials.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.