SBIR Phase I: Low Cost, High Capacity Lithium-Ion Batteries Based On Nano-Structured Silicon Anodes And Ionic Liquid Electrolytes

这个小企业创新研究第一阶段项目将引入一种制造锂离子电池高容量硅纳米线阳极的新方法。在所有负极材料中，硅具有最高的锂吸收容量（4200毫安时/克），而目前锂离子电池中现有的负极材料的容量只有372毫安时/克。然而，硅阳极的采用受到以下事实的限制：在循环过程中，由于体积膨胀，大量硅粉被粉碎。然而，制造纳米结构硅阳极的方法要么昂贵，要么不适合大规模生产，要么受到比容量的限制。所提出的方法估计成本低，可扩展制造，并且不受当前用于制造基于纳米结构Si的阳极的技术的任何技术限制。研究人员还建议优化纳米线的形态和结构，以最大限度地提高阳极容量，并使其能够承受超过1000次循环，并保持足够的容量。此外，研究人员提出将离子液体电解质与硅纳米线阳极集成，预计将显示出高电压稳定性。这个项目的广泛影响/商业潜力确实具有变革性。这项研究将有助于更好地理解利用硅纳米线阳极的电池中的电化学反应。这种制造阳极的新方法可能会在其他技术中得到应用，例如热电设备、气体/化学传感器和生物医学设备。预计这种低成本技术的商业影响也将非常显著。迄今为止报道的硅纳米结构电池使用了昂贵的方法来制造纳米线和集流器。研究人员设想，他们独特的颠覆性方法将使超大容量阳极（~3000 mAh/g）大规模成为可能。阳极容量的增加将导致整个电池组的能量密度增加50%-60%。由于锂离子电池预计将在消费设备存储以及工业和电动汽车（EV）应用中发挥越来越大的作用，这将产生巨大的社会和环境影响。首先，电动汽车不充电的行驶距离将会延长，从而导致电动汽车的广泛采用。电池容量的增加也将为使用可再生能源的住宅和电网存储提供解决方案。

This Small Business Innovation Research Phase 1 project will introduce a novel method of manufacturing a high capacity Si nanowire anode for Li-ion battery applications. Si has the highest lithium absorption capacity of any anode material (4200 mAh/g) whereas the incumbent anode material in today's Li-ion batteries has a capacity of only 372 mAh/g. The adoption of Si anodes however, is limited by the fact that bulk Si pulverizes due to volume expansion during cycling. Nanostructured Si does not pulverize, however, the approaches to make nanostructured Si anodes are either expensive, or not suitable for mass manufacturing, or limited by specific capacity. The proposed method is estimated to be low cost, scalable for manufacturing, and does not suffer from any of the technical limitations of current technologies used to fabricate anodes based on nanostructured Si. The researchers also propose to optimize the nanowire morphology and architecture for maximizing the anode capacity and enabling it to withstand more than 1,000 cycles with sufficient capacity retention. Furthermore, the researchers propose to integrate an ionic liquid electrolyte with the Si nanowire anode, which is expected to show high voltage stability. The broader impact / commercial potential of this project is truly transformational. This research will lead to a better understanding of electrochemical reactions in cells utilizing Si nanowire anodes. The novel approach to fabricate the anode may find use in other technologies such as in thermoelectric devices, gas / chemical sensors, and biomedical devices. The commercial impact of this low-cost technology is also expected to be highly significant. The batteries with Si nanostructures reported to-date have used expensive methods to create nanowires and current collectors. The researchers envision that their unique and disruptive approach will make ultra-high capacity anodes (~3000 mAh/g) possible on a large scale. The increase in anode capacity will result in an estimated 50%-60% increase in energy density for the total battery pack. Since Li-ion batteries are expected to play an increasingly larger role in consumer device storage as well as in industrial and electric vehicle (EV) applications, this would have a tremendous social and environmental impact. For one, the range that EVs can travel without a charge will be extended, thereby leading to widespread adoption of EVs. The increased battery capacity will also lead to solutions for residential and grid storage wherever renewable energy is used.