Bridging Mechanics and Electrochemistry: Theories and Experiments on Battery Materials

机械问题在能量储存、转换和收集中无处不在。可充电电池是便携式电子设备和汽车运输电气化的关键推动因素，但其机械退化会影响当前技术的性能，并限制下一代高容量能源材料的实施。该项目旨在描述电池的老化机制，这也将促进具有增强机械可靠性的储能材料的开发。这将通过通过理论建模和实验表征的紧密结合，重点了解机械力和电化学或能量存储性能之间的基本耦合来实现。这项研究的结果将对行业的各个部门产生广泛的影响，从可穿戴电子产品到电动汽车。在教育方面，该项目将为培养电化学和力学等复杂科学领域的研究生创造机会，并为学生提供储能材料力学方面的教育。外展活动还将加强与普渡大学女性工程项目的现有合作，以鼓励女学生参与工程科学。本项目的总体目标是利用电池材料的综合理论和实验来揭示力学和电化学之间的基本耦合。研究工作包括制定应力调制电子转移和离子扩散理论，以了解对能量容量的影响。同样，应力-成分-反应耦合的连续统理论将为理解机械应力如何调节电化学过程以及后者如何介导能源材料的失效和老化奠定基础。电池非均质结构的计算建模将促进对应力调节动力学和容量的理解。实验将使用能量收集装置和固态电池，结合一种新型电化学纳米压头和基于机械测试标准的压头，为连续统理论的验证提供数据。

Mechanical issues are ubiquitous in energy storage, conversion, and harvesting. In rechargeable batteries, which are a key enabler of portable electronics and electrification of automotive transportation, mechanical degradation compromises the performance of current technology and limits the implementation of next-generation high-capacity energy materials. This project seeks to describe the aging mechanisms in batteries, which would also facilitate the development of energy storage materials with enhanced mechanical reliability. This will be achieved through a focus on understanding the fundamental coupling between mechanical forces and electrochemistry or energy storage performance via a close integration of theoretical modeling and experimental characterizations. The outcome of this research will have a broad impact on diverse sectors of the industry, from wearable electronics to electric cars. On the education front, the project will create opportunities to train graduate students in the complex sciences of electrochemistry and mechanics as well as educate students in the mechanics of energy storage materials. The outreach activities will also enhance an existing collaboration with the Women in Engineering program at Purdue to encourage participation of female students in engineering sciences.The overarching goal of this project is to unravel the fundamental coupling between mechanics and electrochemistry using integrated theories and experiments on battery materials. Research effort include formulating a theory of stress-modulated electron transfer and ion diffusion to understand the effects on energy capacity. Similarly, the continuum theory of stress-composition-reaction coupling will lay a foundation for understanding how mechanical stress modulates the electrochemical processes and how the latter mediates failure and aging of energy materials. The computational modeling of heterogeneous structures in batteries will advance the understanding of stress-regulated kinetics and capacity. The experiments will use energy harvester devices and solid-state batteries in conjunction with a novel electrochemical nano-indenter and coupons based on mechanical testing standards to provide data for the validation of the continuum theories.