PFI-TT: Development of Lithium Metal Battery with Enhanced Reliability

这项创新技术转化伙伴关系（PFI-TT）项目的更广泛影响/商业潜力是提高电动汽车和其他储能应用中锂金属电池的可靠性。为了使电动汽车的制造成本低于内燃机汽车，有必要将电池组的每千瓦时成本从2020-21年的约150美元/千瓦时降低到100美元/千瓦时以下（美国主流采用65-70美元/千瓦时）。目前的锂离子电池正达到其能量密度的极限。因此，下一代电池必须利用新材料。在各种选择中，锂金属提供了最高的理论容量，与目前的锂离子电池相比，电池级能量密度的潜在容量为~2x，成本降低~2x。到2025年，全球电动汽车电池市场预计将增长到约1000亿美元。此外，储能服务市场也有望在未来5年及以后开始快速增长。这个项目改进了锂金属电池。拟议的项目重点是展示锂金属电池使用薄膜或涂层作为锂金属表面的调制层，以实现稳定，可靠的反应。锂表面本质上是不稳定的，这会导致意想不到的反应和结构。这些可能导致内部短路，早期电池故障和安全隐患。不规律的反应也会导致部分锂金属变得不活跃，导致容量衰减和热失控。该涂层通过锂助焊剂调节局部电化学过程，促进锂表面反应均匀。该项目旨在开发一种可扩展的无溶剂、热增强和场辅助方法来设计锂表面涂层的离子传输特性。柔性涂层通过调节锂离子通过的方式与锂表面相互作用。随后，该项目将系统地测试配备这种无溶剂工程界面的锂金属电池的性能。提出的技术提高了锂金属电池的可靠性，并为其商业化铺平了道路。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The broader impact/commercial potential of this Partnerships for Innovation - Technology Translation (PFI-TT) project is to improve the reliability of lithium metal batteries for electric vehicles and other energy storage applications. It is necessary to reduce battery pack cost-per-kWh from about $150/kWh in 2020-21 to under $100/kWh ($65-70/kWh for mainstream adoption in the US) to make electric vehicle manufacturing cost lower than that for internal combustion engine-based vehicles. Current lithium ion batteries are reaching their limit of energy density. As a result, next generation batteries must take advantage of new materials. Among the various choices, lithium metal provides the highest theoretical capacity and with a potential capacity of ~2x energy density at the cell level and ~2x lower cost compared to current lithium ion batteries. The global electric vehicle battery market is estimated to grow to about $100 billion in 2025. In addition, the energy storage services market is also expected to start growing rapidly during the next 5 years and beyond. This project improves lithium metal batteries.The proposed project focuses on demonstrating lithium metal batteries using a thin film or a coating as a modulation layer on the lithium metal surface to achieve a stable, reliable reaction. A lithium surface is inherently unstable, which leads unintended reactions and structures. These can lead to inner short-circuit, early battery failure and safety hazard. Irregular reactions also cause part of the lithium metal to become inactive, leading to capacity decay and thermal runaway. By adjusting the local electrochemical process through lithium flux, the coating promotes uniform lithium surface reaction. This project aims to develop a scalable solvent-free, thermally-enhanced and field-assisted approach to engineer the ionic transport properties of the coating on lithium surface. The flexible coating acts to interact with the lithium surface by regulating how lithium ions pass through it. Subsequently the project will systematically test the performance of lithium metal batteries equipped with such solvent-free engineered interfaces. The proposed technology enhances the reliability of lithium metal batteries, and paves the way for their commercialization.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.