CAREER: Elucidation and Development of Electrolyte and Interface Mechanisms Governing Calcium Redox in Nonaqueous Environments

职业：阐明和开发非水环境中控制钙氧化还原的电解质和界面机制

• 批准号: 2045868
• 负责人: Betar Gallant
• 金额: $ 54.86万
• 依托单位: Massachusetts Institute of Technology
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-03-01 至 2026-02-28
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2045868&HistoricalAwards=false
• 关键词: CAREER; Elucidation; Development; Electrolyte; Interface

Electrochemical energy storage plays a critical role in storing energy from intermittent renewable sources, such as solar and wind energy, and making these sources suitable for electrified transportation. Today’s lithium (Li)-ion and emerging Li metal-based batteries have high energy densities, but they suffer from safety and performance issues along with increasing concerns about scarcity of Li resources. Calcium (Ca) presents a compelling alternative as the basis for next-generation batteries: it is the 5th most abundant element in the earth’s crust, and batteries utilizing Ca metal anodes are projected to have energy storage capabilities comparable to Li counterparts with potential for improved safety. However, development of Ca batteries has been hindered by numerous challenges, including formation of blocking interfaces on Ca metal anodes that impede reversibility, and the need to design electrolytes specifically optimized for divalent Ca ion electrochemistry. This research will build the fundamental understanding of Ca-based electrochemical reactions and the resulting interfaces on Ca metal. To achieve these aims, this research will create tools to conduct novel experimental, quantitative analysis of Ca electrolyte and interface thermochemistry that will guide design of improved Ca batteries. As an additional outcome of the work, middle-school students will engage in active virtual teaching modules that use outcomes of this research while fulfilling a Massachusetts state education standard, bringing exposure to scientists and engineers and motivating pursuit of STEM careers.This research effort will conduct a targeted experimental study of the chemical, thermodynamic and interface parameters that govern Ca ion redox behavior and elucidate Ca solid electrolyte interphase (SEI) chemistry and properties. The central hypothesis guiding this work is that the heightened degrees of freedom in Ca2+ ion solvation present new opportunities to intervene in electrochemical pathways, which can allow reversibility and reaction selectivity to be unlocked if better understood. The tools to be developed to test this hypothesis include a new thermodynamic framework for measuring the solvated Ca state using reaction calorimetry; metal deposition methodologies to prepare high-quality Ca metal interfaces for fundamental study; an operando approach to probe the chemical dynamics of Ca SEI formation; and a cathode conversion reaction involving Ca and CO2 to test and strengthen understanding of how Ca2+ solvation affects reactivity. The results will be integrated to identify the fundamental origins that determine electrochemical parameters: redox potential, Coulombic efficiency, cycle life, and rate capability, and therein identify strategies to improve them. Collectively, this work will yield progress in anode, cathode, and electrolyte aspects of Ca batteries.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.

电化学能源存储在从可再生能源（例如太阳能和风能）中存储能量中起着至关重要的作用，并使这些来源适合电气运输。当今的锂（Li）-OIN和新兴的LI金属电池具有很高的能量密度，但它们遭受了安全性和性能问题的困扰，以及对Li Resources稀缺性的越来越关注。钙（CA）提出了一种引人注目的替代方案，作为下一代电池的基础：它是地壳中第五大元素，并且利用CA金属阳极的电池预计具有可与Li的储能能力相媲美，可与Li的储能能力相当，具有提高安全性的潜力。但是，CA电池的开发受到了许多挑战的阻碍，包括在CA金属阳极上形成阻碍可逆性的封闭界面，以及设计针对Divalent CA离子电化学专门优化的电解质的需求。这项研究将建立对基于CA的电化学反应以及CA金属上产生的界面的基本理解。为了实现这些目标，这项研究将创建工具，对CA电解质和界面热化学进行新颖的实验，定量分析，以指导改进的CA电池的设计。作为工作的额外结果，中学的学生将参与积极的虚拟教学模块，同时履行马萨诸塞州的州教育标准，使科学家和工程师接触到科学家和工程师，并激励对STEM职业的追求。这项研究将对化学，热力学和界面式（CA）进行有针对性的实验研究，以控制CA的ca see capiention Capienty Capiention Capienty Capiention Capient capient capiention Capient capiatient Capiente Capection Cape catient catient catient Capection Caprient catient catient（和属性。指导这项工作的中心假设是，CA2+离子解决方案中的自由度提高为干预电化学途径提供了新的机会，如果更好地理解，可以使可逆性和反应选择性解锁。用于检验该假设的工具包括一个新的热力学框架，用于使用反应量热法测量解决的CA态；金属沉积方法准备高质量的Ca金属界面进行基础研究；操作方法探测Ca Sei形成的化学动力学；以及涉及CA和CO2的阴极转化反应测试和加强对CA2+溶液如何影响反应性的理解。结果将集成以确定确定电化学参数的基本起源：氧化还原电位，库仑效率，循环寿命和速率能力，并确定改善它们的策略。总的来说，这项工作将在CA电池的阳极，阴极和电解质方面取得进展。该奖项反映了NSF的法定任务，并通过使用基金会的知识分子优点和更广泛的影响评估标准来诚实地通过评估来诚实地支持。