Elements: Open-Source Battery Electrode Simulation Toolkit using MFEM (BESFEM)

电池已经成为我们现代生活中不可或缺的商品，为手机、笔记本电脑、电动工具和电动汽车提供动力。电池的关键部件是电极，电极由填充的锂储存颗粒组成。因此，电极具有复杂的微观结构，具有卷曲的空间和不规则的颗粒。电池中的充放电过程涉及离子和电子迁移的耦合物理机制，这些复杂的电极。因此，由于这些复杂性，研究电池现象变得具有挑战性。该项目的目标是开发一个开源的电池电极仿真工具包(BESFEM)。该工具包将能够快速模拟复杂电极微结构中的电化学过程。它将对实验重建的电极微结构进行详细的模拟，结果可以在类似虚拟现实的环境中可视化。用户将能够在不同的微结构和不同的循环条件下以数字方式探索电化学过程。该软件不仅可以作为提高电池性能和减轻电池故障的设计工具，还可以作为培训材料科学家的教育工具。这项工作将加快美国汽车行业电池和网格级储能的发展。传统的尖锐界面模拟要求网格系统符合求解控制方程的感兴趣的领域。然而，为复杂微结构生成网格是一项具有挑战性的任务。为了解决这一问题，我们的研究团队采用了平滑边界方法(SBM)，该方法利用连续的区域函数来描述几何图形并重新表述相关的电化学控制方程。这种形式可以在规则的笛卡尔网格上求解新的方程，消除了对身体协调网格的需要。值得注意的是，SBM方程可以直接在重建的三维微结构的体素数据上求解，大大减少了模拟准备所花费的时间。BESFEM将SBM方法集成到美国能源部亿级计算项目的产品--MFE解算器库中。为了提高精度和计算效率，我们的团队将利用MFE的混合顺序单元功能，在该功能中，为SBM漫反射界面附近的单元分配高阶形状函数。MFE已经证明了它可以扩展到数百万个并行CPU任务，并支持GPU计算。因此，BESFEM将大大加快电极微结构模拟的速度和规模。这一能力将使BESFEM能够进行高通量类型的微结构模拟，以提取电极的结构-性能关系。拟议的软件开发将遵循软件工程的最佳实践，该产品将作为电池科学和材料科学界的研究和教育工具全面提供。该奖项由高级网络基础设施办公室颁发，由化学、生物工程、环境和运输系统司以及工程局内的电化学系统计划联合支持。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Batteries have become an indispensable commodity in our modern lives, powering mobile phones, laptops, power tools, and electric vehicles. The crucial components of a battery are electrodes, which consist of packed lithium-storage particles. As a result, electrodes possess complex microstructures with convoluted spaces and irregular particles. The charge-discharge processes in batteries involve coupled physics mechanisms of the migration of ions and electrons these complex electrodes. Consequently, investigating battery phenomena becomes challenging due to these complexities. The objective of this project is to develop an open-source Battery Electrode Simulation toolkit using MFEM (BESFEM). This toolkit will enable rapid simulation of electrochemical processes in complex electrode microstructures. It will perform detailed simulations on experimentally reconstructed electrode microstructures, and the results can be visualized in a virtual-reality-like environment. Users will be able to digitally explore electrochemical processes in various microstructures and under different cycling conditions. Not only can this software serve as a design tool for enhancing battery performance and mitigating battery failures, but it can also serve as an educational tool for training materials scientists. This work will accelerate battery development in the US automotive industry and grid-level energy storage. Conventional sharp-interface simulations require mesh systems that conform to the domain of interest for solving governing equations. However, generating meshes for complex microstructures poses a challenging task. To address this, our research team employs the smoothed boundary method (SBM), which utilizes a continuous domain function to describe geometries and reformulate the relevant electrochemical governing equations. This formulation enables solving the new equations on a regular Cartesian grid, eliminating the need for body-conforming meshes. Remarkably, the SBM equations can be directly solved on voxel data of reconstructed 3D microstructures, significantly reducing the time spent on simulation preparation. BESFEM integrates the SBM approach on the MFEM solver library, a product of the DOE's Exascale Computing Project. To enhance accuracy and computational efficiency, our team will leverage MFEM's hybrid order cells functionality, where elements near SBM diffuse interfaces are assigned with high-order shape functions. MFEM has demonstrated its scalability to millions of parallel CPU tasks and also supports GPU computing. Consequently, BESFEM will greatly accelerate the speed and scale of electrode microstructure simulations. This capability will allow BESFEM to conduct high-throughput-type microstructure simulations to extract the structure-performance relationship of electrodes. The proposed software development will follow the best practice of software engineering and the product will be made fully available as a research and education tool for the battery science and materials science communities.This award by the Office of Advanced Cyberinfrastructure is jointly supported by the Division of Chemical, Bioengineering, Environmental, and Transport Systems, and the Electrochemical Systems program, within the Directorate for Engineering.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.