SBIR Phase I: Mesoporous Graphene Electrodes for Supercapacitors

这个小企业创新研究第一阶段项目将开发用于超级电容器的高电容、低电阻石墨烯电极，以实现高功率和能量密度。目前使用的活性炭电极比电容过低是高性能超级电容器的主要技术障碍之一。这种屏障主要是由于电解质难以进入活性炭表面：很大一部分表面积以微孔（直径2nm）的形式存在，因此离子无法迁移，因此无法促进能量储存。石墨烯是一种单原子厚度、导电的碳同素异形体，具有极高的比表面积、卓越的导热/导电性、开放的微观结构和良好的热稳定性。这家小型企业与北卡罗来纳大学合作，将利用新发现的石墨烯路线，为超级电容器生产机械稳定、灵活的介孔电极，这些电极将实现更高的能量存储容量和增强的性能。这个项目更广泛的商业影响在于超级电容器可以实现许多应用。预计消费电子领域对超级电容器的需求将从2008年的1.22亿美元增加到2014年的5.5亿美元以上。此外，在风力涡轮机和混合动力汽车（hev）等大型存储应用中，超级电容器的市场价值预计将从去年的8600万美元扩大到五年内的3.2亿美元以上。在混合动力汽车的关键技术中，超级电容器将通过两个主要功能来提高油耗：平衡动态功率负载，以及从再生断裂中恢复可用能量。美国政府对推动混合动力汽车的发展有着浓厚的兴趣，以减少对外国石油的依赖，并应对全球气候挑战。在私营部门，领先的汽车公司正在开发混合动力汽车，作为内燃机动力汽车的替代品。基于石墨烯的超级电容器提供了在混合动力应用中获得高脉冲功率所需的高能量/功率密度的潜力。

This Small Business Innovation Research Phase I Project will develop high capacitance, low resistance graphene electrodes for supercapacitors to achieve high power and energy densities. One of the major technical barriers to high performance supercapacitors is low specific capacitance of the currently used activated carbon electrodes. This barrier is primarily due to poor access to the activated carbon surface area by an electrolyte: a substantial fraction of the surface area is in the form of micropores ( 2nm diameter) and consequently inaccessible to ion migration and therefore, unable to contribute to energy storage. This difficulty can be ameliorated by replacing microporous activated carbon with graphene, a one-atom-thick, conductive allotrope of carbon with a rare combination of extremely high specific surface area, remarkable thermal/electrical conductivity, an open microstructure, and good thermal stability. The small business, in collaboration with the University of North Carolina, will exploit the newly discovered route to graphene to produce mechanically stable, flexible, mesoporous electrodes for supercapacitors, electrodes that will achieve higher energy storage capacity and enhanced performance.The broader/commercial impact of this project lies in the many applications that can be enabled by supercapacitors. It is expected that the demand for supercapacitors in consumer electronics will increase from $122 million in 2008 to over $550 million in 2014. And, in large storage applications such as wind turbines and hybrid electric vehicles (HEVs), the market value of supercapacitors is expected to expand from $86 million last year, to over $320 million in five years. In the critical technologies of HEVs, supercapacitors will enable improved gas mileage via two primary functions: leveling the dynamic power loads, and recovering available energy from regenerative breaking. The U.S. government has a strong interest in advancing HEVs to lessen dependence on foreign oil and address the global climate challenge. In the private sector, leading automotive companies are developing HEVs as an alternative to internal combustion engine-powered vehicles. Graphene-based supercapacitors offer the potential for attaining the requisite high energy/power density for high pulse power in HEV application.