SBIR Phase I: High-Performance, Low-Cost Anode-Free Lithium-Ion Batteries for Electric Vehicles and Consumer Electronics

这项小型企业创新研究（SBIR）项目的更广泛影响/商业潜力是为电动汽车（EV）电池组创造一种新型锂离子电池。乘用车占全球石油消耗量的27%。该材料将使新型廉价的远程电动汽车成为可能，电池尺寸将缩小65%，电池成本将降低40%。该SBIR一期项目旨在利用电化学和薄膜表征技术了解形成条件和电解质成分对无阳极固体电解质界面（SEI）生成的影响。在缺乏坚固的SEI的情况下，无阳极电池会经历快速的容量损失，这要么是由于“苔藓状”的锂生长，要么是由于电解质的急剧分解。这些降解途径导致的细胞在室温下通常功能少于50个循环。在恒流充放电过程中，形成温度和电流密度对无阳极SEI形成的影响将使用扫描电子显微镜（SEM）和x射线光电子能谱（XPS）以及传统的电化学技术进行分析。这些技术还将测量不同电解质盐/溶剂组成对无阳极SEI形成的影响。在优化的SEI条件下，温度对循环寿命的依赖关系将通过恒流充放电来评估。该项目的主要目标是阐明形成条件和电解质成分，从而产生光滑的SEI层，其特征是理想的锂马赛克柱，能够在室温下以最小的容量衰减进行可逆循环。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 Small Business Innovation Research (SBIR) project is to create a new type of lithium-ion battery for electric vehicle (EV) battery packs. Passenger vehicles representing 27% of global oil consumption. The proposed material will enable a new affordable, long-range EV reducing battery costs by reducing the battery size by 65% and the cell cost by up to 40%. This SBIR Phase I project proposes to understand the influence of formation conditions and electrolyte composition on the generation of anode-free solid electrolyte interphase (SEI) using electrochemical and thin film characterization techniques. In the absence of a robust SEI, anode-free batteries experience rapid capacity loss that stems from either “mossy” lithium growth or precipitous electrolyte decomposition. These degradation routes result in cells that typically function for less than 50 cycles at room temperature. The impact of formation temperature and current density on anode-free SEI formation during galvanostatic charge/discharge will be analyzed using Scanning Electron Microscopy (SEM) and X-ray Photoelectron Spectroscopy (XPS) as well as conventional electrochemical techniques. These techniques will also measure the impact of varying electrolyte salt/solvent compositions on anode-free SEI formation. The dependence of temperature on cycle life with the optimized SEI conditions will be evaluated through galvanostatic charge/discharge. The key objective of the project is to clarify the formation conditions and electrolyte composition that results in the generation of a smooth SEI layer featuring ideal lithium mosaic columns capable of reversibly cycling with minimal capacity fade at room temperature.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.