Battery Cathodes with Optimized Interfacial Stability Through the Tailored Design of Core-Shell Architectures

通过核壳结构的定制设计优化界面稳定性的电池正极

• 批准号: 1605126
• 负责人: Jordi Cabana
• 金额: $ 30.86万
• 依托单位: University of Illinois at Chicago
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-07-01 至 2022-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1605126&HistoricalAwards=false
• 关键词: Battery; Cathodes; Optimized; Interfacial; Stability

Rechargeable lithium ion batteries help to enable sustainable energy systems by storing electricity generated by intermittent renewable resources such as wind and solar energy, or by powering zero-emission electric vehicles charged by electricity from renewable resources. However, the performance of lithium ion batteries degrades over repeated recharging cycles because of unwanted reactions that occur at the boundary between the battery electrode and the electrolyte. This project will develop new electrode materials for preventing these unwanted reactions. The key innovation is to coat nanoscale crystals of the lithium-based energy storage material with a very thin layer of other materials that are tailored to block these undesired reactions but maintain performance. The coating is uniformly applied to all the nanocrystals, and so that when the crystals are formed into an electrode, there are no gaps in the coating. The educational activities associated with this project involve mentoring of undergraduate students for summer research, and outreach to high school students in the Chicago area. The goals of the outreach activities are to communicate the value of energy storage technology in modern society to diverse groups of high school students in the Chicago area, and to encourage these students to pursue education and careers in STEM fields. This overall goal of this research is to improve the ability of lithium ion battery cathodes to withstand extreme cycling environments by maximizing interfacial stability without sacrificing energy storage capacity, power delivery, and recharging time. Cathode-electrolyte instabilities have been linked to the presence of electroactive transition metals at the surface of the electrode. These instabilities result in irreversible transformations at these interfaces, with formation of insulating layers that impede transport as well as material loss due to corrosion. Core-shell architectures can address interfacial instability. The shell will be rich in inactive aluminum ions that minimize irreversible transformations at the interface, and the core will be composed of active transition metal oxides (Mn, Ni, Co) with high charge storage capacity. Furthermore, the shell will be thin to reduce storage capacity loss, and conformal to passivate all interfaces. To gain a fundamental understanding of the ability these core-shell cathode materials to maintain electrode stability, the research plan has three objectives. The first objective is to fabricate core-epitaxial shell nanocrystals for high voltage, high energy battery cathodes. The second objective is to design and evaluate core-shell architectures at the secondary particle level, and the third objective is to construct of full lithium ion cells and characterize of their interfacial mechanisms of operation. As part of this research, synthesis and fabrication tools will be developed to effectively coat all interfaces with tailored materials and create integrated cathode architectures where appropriate levels of electron and ion transport are imparted.

可充电锂离子电池通过存储风能和太阳能等间歇性可再生资源产生的电力，或为零排放电动汽车提供动力，从而帮助实现可持续能源系统。 然而，由于在电池电极和电解质之间的边界处发生的不希望的反应，锂离子电池的性能在重复的再充电循环中降低。该项目将开发新的电极材料，以防止这些不必要的反应。 关键的创新是在锂基储能材料的纳米级晶体上涂上一层非常薄的其他材料，这些材料可以阻止这些不期望的反应，但保持性能。 涂层均匀地施加到所有纳米晶体上，并且使得当晶体形成电极时，涂层中没有间隙。 与该项目相关的教育活动包括指导本科生进行夏季研究，并向芝加哥地区的高中生推广。 外展活动的目标是向芝加哥地区的不同高中生群体传达储能技术在现代社会中的价值，并鼓励这些学生在STEM领域接受教育和从事职业。 本研究的总体目标是通过最大限度地提高界面稳定性，在不牺牲能量存储容量、功率传输和充电时间的情况下，提高锂离子电池阴极承受极端循环环境的能力。 阴极电解质不稳定性与电极表面存在电活性过渡金属有关。 这些不稳定性导致这些界面处的不可逆转变，形成绝缘层，其阻碍运输以及由于腐蚀引起的材料损失。核-壳结构可以解决界面不稳定性。 壳将富含使界面处的不可逆转变最小化的非活性铝离子，并且核将由具有高电荷存储容量的活性过渡金属氧化物（Mn、Ni、Co）组成。此外，壳体将是薄的以减少存储容量损失，并且保形以钝化所有界面。 为了从根本上了解这些核壳阴极材料保持电极稳定性的能力，研究计划有三个目标。第一个目标是制造用于高电压、高能量电池阴极的核-外延壳纳米晶体。 第二个目标是在二次粒子水平上设计和评估核-壳结构，第三个目标是构建完整的锂离子电池并表征其界面操作机制。 作为这项研究的一部分，将开发合成和制造工具，以有效地涂覆定制材料的所有界面，并创建集成的阴极架构，其中赋予适当的电子和离子传输水平。