Revealing the Inside of a Nanoscale Na-ion Battery: New Understanding on Sodium Intercalation in Cathodes

该基金的研究目标是促进对电极中钠离子反应和钠离子电池中化学诱导失效和断裂的潜在机制的理解。 为此，阴极电极将在透射电子显微镜（TEM）内进行电化学探测，其中电极的微观结构可以同时以高分辨率进行监测。 室温可充电钠离子电池由于其较低的成本和钠资源的广泛可用性而可以与锂离子电池竞争。 虽然全球范围内的大量研究都集中在锂离子电池上，但与室温可充电钠离子电池相关的科学挑战相对未被探索。 考虑到锂资源非常有限，并且在过去20年中其价格持续上涨，这是至关重要的。 Na离子电池的挑战比Li离子情况复杂得多，因为Na离子比Li离子大70%，这在将Na离子驱动到主电极中时引起大的机械应力。 钠离子进入电极会引发复杂的化学反应和故障，电池寿命会大幅缩短。钠离子电池广泛使用的一个重要挑战是在使用条件下循环稳定性极低。 通过这笔赠款，PI将研究新阴极材料中几个尚未解决的科学挑战，如果成功解决，可以实现长期可充电钠离子电池技术的商业化。 几个场地整合研究与本科教育和推广活动的建议。 本科教育的女性和少数民族学生将通过简单的介绍电池主题接触到这个研究项目。 还计划为当地高中女生和代表性不足的学生开展其他外联活动。 将制作显微镜实验的真实的实时视频，并通过YouTube©和选定的科学网络提供给社区。

The research objective of this grant is to advance the understanding of the underlying mechanisms that are active in Na-ion reactions in electrodes and chemically-induced failure and fracture in Na-ion batteries. For this purpose, the cathode electrode will be subjected to electrochemical probing inside a transmission electron microscope (TEM) where the microstructure of electrodes can be simultaneously monitored in high resolution. Room-temperature rechargeable Na-ion batteries can be competitive to Li-ion batteries due to their lower cost and the widespread availability of the sodium resources. While tremendous research is focused on Li-ion batteries worldwide, scientific challenges associated with room-temperature rechargeable sodium-ion batteries have been relatively unexplored. This is of prime importance considering that Li resources are very limited and their price has increased continuously during the past 20 years. The challenges of Na-ion batteries are much more complicated than the Li-ion case, as Na-ions are larger than Li-ions by 70%, which induces large mechanical stresses upon driving the Na-ions into the host electrode. The entry of sodium into the electrodes triggers complicated chemical reactions and failures that are poorly understood, and the battery life is reduced drastically.An important challenge in the broad use of Na-ion batteries is the very low cycling stability in service conditions. Through this grant, the PI will investigate several unresolved scientific challenges in new cathode materials which, if successfully resolved, could enable the commercialization of long lasting rechargeable Na-ion battery technologies. Several venues for integrating research with undergraduate education and outreach activities are proposed. Female and minority students for undergraduate education will be exposed to this research project through simple introductions to the battery subject. Other outreach activities are also planned for local high school female and underrepresented students. Real time videos of microscopy experiments will be produced and made available to the community via YouTube© and selected scientific networks.