SBIR Phase I: High Capacity Li2S-Si Rechargeable Batteries for Energy Storage Applications

这个小企业创新研究第一阶段项目将开发一种基于硫化锂-碳复合阴极和硅阳极的新型二次电池平台，该平台具有高能量密度和长循环寿命。如今，移动设备需要更快的性能和更小的尺寸以获得更好的便携性。然而，这些设备中更快的处理器施加了能量密度要求，将当今的锂电池技术推向了极限。基于锂离子电池平台，Li2S/Si配置提供了最高的理论比能（1.55 kWh/kg），而且不受其他使用金属锂的二次锂电池系统相关的安全问题的影响。锂电池的阴极和阳极循环寿命有限，阻碍了锂电池的发展。在阴极方面，该公司开发了用于固硫的多孔碳载体的方法，以及在阳极方面合成硅纳米线以防止粉碎的方法，从而获得了两个电极的稳定性能。在一期项目中，该公司将优化其电极的性能并开发可扩展的生产工艺。这项研究将导致Li2S/Si平台的持续性能改进，并确定扩大规模的关键处理技术和挑战。该项目的更广泛的影响/商业潜力在于，它能够给可充电锂电池技术和市场带来重大变化，因为它的能量密度比目前的化学平台（0.2-0.6 kWh/kg）优势大约三倍。锂离子电池（LIB）目前的市场规模为110 - 130亿美元，预计到2020年，其销售额将至少增加到400亿美元。lib广泛应用于便携式电子产品，有望成为新一代混合动力汽车和电动汽车发展的推动力。如果所提出的技术能够商业化，则更高的能量密度、更高的功率和更长的循环寿命等改进的性能特征将使制造商/消费者能够为其设备/车辆提供更长时间的动力，并在各自的应用中获得性能优势。

This Small Business Innovation Research Phase I project will develop a novel secondary battery platform based on a lithium sulfide-carbon composite cathode and a silicon anode that demonstrates high energy density and long cycle life. Today, mobile devices require faster performance and smaller sizes for greater portability. However, the faster processors in these devices impose energy density requirements that push today's lithium battery technologies to their limits. Li2S/Si configuration offers the highest theoretical specific energy (1.55 kWh/kg) based on the lithium-ion battery platform and furthermore is not subject to the safety issues related to other secondary lithium battery systems which employ metallic lithium. The development of the Li2S/Si battery has been hindered by the limited cycle life of the cathode and the anode. On the cathode side the company has developed methods of creating porous carbon hosts for sequestering sulfur and on the anode side methods of synthesizing Si nanowires to prevent pulverization, hence obtaining stable performance for both electrodes. In the Phase I Project the company will optimize performance of their electrodes and develop scalable processes for production. This research will result in continued performance improvement of the Li2S/Si platform and identify critical processing techniques and challenges for scale-up.The broader impact/commercial potential of this project is that it is able to bring about significant changes to the rechargeable lithium battery technologies and the market because of their approximately three fold energy density advantage over the current chemistry platforms (0.2-0.6 kWh/kg). Lithium-ion batteries (LIB) currently have a market of $11-13 billion and the sales are expected to increase to at least $40 billion by 2020. LIBs are widely employed in portable electronics and are expected to be the driving force for development of the new generation of hybrid and electric vehicles. If the proposed technology can be brought to commercialization, the improved performance characteristics such as higher energy density, higher power and longer cycle life will allow manufacturers/consumers to power their devices/vehicles for longer periods of time and gain performance advantages in their respective applications.